Tricks of the Windows Gam…ming Gurus (2nd Edition)/Disc2.iso/msdn_vcb/samples/vc98/sdk/graphics/video/aviedit/aviedit.c

C/C++ Source or Header | 1997-10-05 | 100.3 KB | 3,378 lines

/****************************************************************************
 *
 *  AVIEDIT.C
 *
 *  Sample program using the AVIFile read/write routines
 *
 **************************************************************************/
/**************************************************************************
 *
 *  THIS CODE AND INFORMATION IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY
 *  KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
 *  IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR
 *  PURPOSE.
 *
 *  Copyright (C) 1992 - 1997 Microsoft Corporation.  All Rights Reserved.
 *
 **************************************************************************/

#define STRICT
#define INC_OLE2
#include <windows.h>
#include <shellapi.h>
#include <windowsx.h>
#include <commdlg.h>
#include "muldiv32.h"
#include <vfw.h>

#include "aviedit.h"
#include "audio.h"

#include <limits.h>

#define GlobalSizePtr(lp)   GlobalSize(GlobalPtrHandle(lp))
#define LPPAVIFILE PAVIFILE *
typedef BYTE * HPBYTE;
typedef UNALIGNED short * HPSHORT;

/*----------------------------------------------------------------------------*\
\*----------------------------------------------------------------------------*/
static BOOL gfDefDlgEx = FALSE;         //the recursion flag for message crackers

#define BUFSIZE 260
static char gszBuffer[BUFSIZE];
static char gszFileName[BUFSIZE];
static char gszSaveFileName[BUFSIZE];

#define AVI_EDIT_CLASS  "edit"
static LPAVISTREAMINFO glpavisi;
static int gnSel;
int     gSelectedStream = -1;   // Highlight this text area when painting
RECT    grcSelectedStream;      // where to highlight

char    gszFilter[512];     // for AVIBuildFilter - more than one string!
static  HINSTANCE   ghInstApp;
static  HWND        ghwndApp;
static  HACCEL      ghAccel;
static  WNDPROC     gOldEditProc;
static  HWND        ghwndEdit;

#define SCROLLRANGE  10000
#define MAXNUMSTREAMS   25

int                 gcpavi;                     // # of streams
PAVISTREAM          gapavi[MAXNUMSTREAMS];      // the current streams
int                 gcpaviSel;                  // num of edit streams
PAVISTREAM          gapaviSel[MAXNUMSTREAMS];   // edit streams to put on clipbd
int                 gStreamTop[MAXNUMSTREAMS+1];// y position of each stream
AVICOMPRESSOPTIONS  gaAVIOptions[MAXNUMSTREAMS];// compression options
LPAVICOMPRESSOPTIONS  galpAVIOptions[MAXNUMSTREAMS];
PGETFRAME           gapgf[MAXNUMSTREAMS];       // data for decompressing video
HDRAWDIB            ghdd[MAXNUMSTREAMS];        // drawdib handles
LONG                galSelStart[MAXNUMSTREAMS];
LONG                galSelLen[MAXNUMSTREAMS];
int                 giFirstAudio = -1;          // 1st audio stream found
int                 giFirstVideo = -1;          // 1st video stream found

#define             gfVideoFound (giFirstVideo >= 0)
#define             gfAudioFound (giFirstAudio >= 0)

BOOL                gfPlaying;          // are we currently playing?
LONG                glPlayStartTime;    // When did we start playing?
LONG                glPlayStartPos;     // Where were we on the scrollbar?
LONG                timeStart;          // cached start, end, length
LONG                timeEnd;
LONG                timeLength;
LONG                timehscroll;        // how much arrows scroll HORZ bar
int                 nVertSBLen;         // vertical scroll bar
int                 nVertHeight;
DWORD               gdwMicroSecPerPixel = 1000L;        // scale for video
WORD                gwZoom = 2;         // one-half zoom (divide by 4)
HWND                ghwndMCI;

// buffer for wave data
LPVOID lpAudio;

// constants for painting
#define VSPACE  8       // some vertical spacing
#define SELECTVSPACE 4 // height of selection line
#define HSPACE  4       // space between frames for video stream
#define TSPACE  10      // space for text area about each stream
#define AUDIOVSPACE  64 // height of an audio stream at X1 zoom

#define HIGHLIGHT       (GetSysColor(COLOR_HIGHLIGHT) ? GetSysColor(COLOR_HIGHLIGHT) : GetSysColor(COLOR_ACTIVECAPTION))

/*----------------------------------------------------------------------------*\
\*----------------------------------------------------------------------------*/

// Macros to get and set the scroll bar to a given millisecond value in the
// movie.  Movie lengths can be DWORDS but we only have 16 bits of resolution.

#define GetScrollTime(hwnd) \
(timeStart + muldiv32(GetScrollPos(hwnd, SB_HORZ), timeLength, SCROLLRANGE))

#define SetScrollTime(hwnd, time) SetScrollPos(hwnd, SB_HORZ, \
(int)muldiv32((time) - timeStart, SCROLLRANGE, timeLength), TRUE)

/*----------------------------------------------------------------------------*\
\*----------------------------------------------------------------------------*/

LRESULT CALLBACK AppWndProc(HWND, UINT, WPARAM, LPARAM );
LRESULT CALLBACK NewEditProc(HWND, UINT, WPARAM, LPARAM );
BOOL CALLBACK    AboutDlgProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam);
int  ErrMsg (LPSTR sz,...);

BOOL MenuHandler( HWND, int );

void editPaste(HWND hwnd, PAVIFILE pfile);
void             FrameVideo(HDC hdc, RECT *rcFrame, HBRUSH hbr);

/*----------------------------------------------------------------------------*\
\*----------------------------------------------------------------------------*/
static int gfWait = 0;

/*----------------------------------------------------------------------------*\
|    StartWait()                                                                |
|    Start a wait operation... put up the hourglass if it's the first call      |
\*----------------------------------------------------------------------------*/
void StartWait()
{
    if (gfWait++ == 0) {
    SetCursor(LoadCursor(NULL,IDC_WAIT));
    }
}

/*----------------------------------------------------------------------------*\
|    EndWait()                                                                  |
|    Once every one who started a wait is finished, go back to regular cursor   |
\*----------------------------------------------------------------------------*/
void EndWait()
{
    if (--gfWait == 0) {
    SetCursor(LoadCursor(NULL,IDC_ARROW));
    InvalidateRect(ghwndApp, NULL, TRUE);
    }
}

/*----------------------------------------------------------------------------*\
|    WinYield()                                                                 |
|    Code to yield while we're not calling GetMessage.                          |
|    Dispatch all messages.  Pressing ESC or closing aborts.                    |
\*----------------------------------------------------------------------------*/

BOOL WinYield(void)
{
    MSG msg;
    BOOL fAbort=FALSE;

    while(gfWait > 0 && PeekMessage(&msg,NULL,0,0,PM_REMOVE))
    {
    if (msg.message == WM_KEYDOWN && msg.wParam == VK_ESCAPE)
        fAbort = TRUE;
    if (msg.message == WM_SYSCOMMAND && (msg.wParam & 0xFFF0) == SC_CLOSE)
        fAbort = TRUE;
    TranslateMessage(&msg);
    DispatchMessage(&msg);
    }
    return fAbort;
}


/*----------------------------------------------------------------------------*\
|    PaintVideo()                                                               |
|    Draw a video frame in the specified rect                                   |
\*----------------------------------------------------------------------------*/

void PaintVideo(HDC hdc, RECT rcFrame, int iStream, LPBITMAPINFOHEADER lpbi, LONG lCurSamp, LONG lPos)
{
    int         iLen;
    COLORREF    nCol;
    char        szText[BUFSIZE];
    RECT        rc;

    //
    // If we have a picture, draw it
    //
    if (lpbi)
    {
    //
    // use the palette of the first video stream
    //
    DrawDibDraw(ghdd[iStream], hdc,
            rcFrame.left, rcFrame.top,
            rcFrame.right - rcFrame.left,
            rcFrame.bottom - rcFrame.top,
            lpbi, NULL,
            0, 0, -1, -1,
            (iStream == giFirstVideo) ? 0 :DDF_BACKGROUNDPAL);

    iLen = wsprintf(szText, "%ld %ld.%03lds",
            lCurSamp, lPos / 1000, lPos % 1000);
    }

    //
    // Before or after the movie (or read error) draw GRAY
    //
    else {
    SelectObject(hdc,GetStockObject(DKGRAY_BRUSH));

    PatBlt(hdc,
           rcFrame.left, rcFrame.top,
           rcFrame.right - rcFrame.left,
           rcFrame.bottom - rcFrame.top,
           PATCOPY);
    iLen = 0;
    szText[0] = '\0';
    }

    //
    // print something meaningful under the frame
    //
    rc.left = rcFrame.left;
    rc.right = rcFrame.right - 2 * HSPACE;      // don't overlap text areas
    rc.top = rcFrame.bottom + HSPACE;
    rc.bottom = rc.top + TSPACE + TSPACE;       // blank out enough space
    nCol = SetBkColor(hdc, GetSysColor(COLOR_WINDOW));
    ExtTextOut(hdc, rc.left, rc.top, ETO_CLIPPED | ETO_OPAQUE,
           &rc, szText, iLen, NULL);
    SetBkColor(hdc, nCol);
}


/*----------------------------------------------------------------------------*\
|    PaintAudio()                                                               |
|    Draw some samples of audio inside the given rectangle                      |
\*----------------------------------------------------------------------------*/

void PaintAudio(HDC hdc, PRECT prc, PAVISTREAM pavi, LONG lStart, LONG lLen)
{
    PCMWAVEFORMAT wf;
    int i;
    int x,y;
    int w,h;
    BYTE b;
    HBRUSH hbr;
    RECT rc = *prc;
    LONG    lBytes;
    LONG    l, lLenOrig = lLen;
    LONG    lWaveBeginTime = AVIStreamStartTime(pavi);
    LONG    lWaveEndTime   = AVIStreamEndTime(pavi);

    //
    // We can't draw before the beginning of the stream - adjust
    //
    if (lStart < lWaveBeginTime) {
    lLen -= lWaveBeginTime - lStart;
    lStart = lWaveBeginTime;
    // right justify the legal samples in the rectangle - don't stretch
    rc.left = rc.right - (int)muldiv32(rc.right - rc.left, lLen, lLenOrig);
    }

    //
    // We can't draw past the end of the stream
    //
    if (lStart + lLen > lWaveEndTime) {
    lLenOrig = lLen;
    lLen = max(0, lWaveEndTime - lStart);   // maybe nothing to draw!
    // left justify the legal samples in the rectangle - don't stretch
    rc.right = rc.left + (int)muldiv32(rc.right - rc.left, lLen, lLenOrig);
    }

    // Now start working with samples, not time
    l = lStart;
    lStart = AVIStreamTimeToSample(pavi, lStart);
    lLen = AVIStreamTimeToSample(pavi, l + lLen) - lStart;

    //
    // Get the format of the wave data
    //
    l = sizeof(wf);
    AVIStreamReadFormat(pavi, lStart, &wf, &l);
    if (!l)
    return;

    w = rc.right - rc.left;
    h = rc.bottom - rc.top;

    //
    // We were starting before the beginning or continuing past the end.
    // We're not painting in the whole original rect --- use a dark background
    //
    if (rc.left > prc->left) {
    SelectObject(hdc, GetStockObject(DKGRAY_BRUSH));
    PatBlt(hdc, prc->left, rc.top, rc.left - prc->left,
           rc.bottom - rc.top, PATCOPY);
    }
    if (rc.right < prc->right) {
    SelectObject(hdc, GetStockObject(DKGRAY_BRUSH));
    PatBlt(hdc, rc.right, rc.top, prc->right - rc.right,
           rc.bottom - rc.top, PATCOPY);
    }

#define BACKBRUSH  (GetSysColor(COLOR_BTNFACE))         // background
#define MONOBRUSH  (GetSysColor(COLOR_BTNSHADOW))       // for mono audio
#define LEFTBRUSH  (RGB(0,0,255))                       // left channel
#define RIGHTBRUSH (RGB(0,255,0))                       // right channel
#define HPOSBRUSH  (RGB(255,0,0))                       // current position

    //
    // Paint the background
    //
    hbr = SelectObject(hdc, CreateSolidBrush(BACKBRUSH));
    PatBlt(hdc, rc.left, rc.top, w, h, PATCOPY);
    DeleteObject(SelectObject(hdc, hbr));

    //
    // !!! we can only paint PCM data right now.  Sorry!
    //
    if (wf.wf.wFormatTag != WAVE_FORMAT_PCM)
    return;

    //
    // How many bytes are we painting? Alloc some space for them
    //
    lBytes = lLen * wf.wf.nChannels * wf.wBitsPerSample / 8;
    if (!lpAudio)
    lpAudio = GlobalAllocPtr (GHND, lBytes);
    else if ((LONG)GlobalSizePtr(lpAudio) < lBytes)
    lpAudio = GlobalReAllocPtr(lpAudio, lBytes, GMEM_MOVEABLE);
    if (!lpAudio)
    return;

    //
    // Read in the wave data
    //
    AVIStreamRead(pavi, lStart, lLen, lpAudio, lBytes, NULL, &l);
    if (l != lLen)
    return;

#define MulDiv(a,b,c) (UINT)((DWORD)(UINT)(a) * (DWORD)(UINT)(b) / (UINT)(c))

    //
    // !!! Flickers less painting it NOW or LATER?
    // First show the current position as a bar
    //
    hbr = SelectObject(hdc, CreateSolidBrush(HPOSBRUSH));
    PatBlt(hdc, prc->right / 2, prc->top, 1, prc->bottom - prc->top, PATCOPY);
    DeleteObject(SelectObject(hdc, hbr));

    //
    // Paint monochrome wave data
    //
    if (wf.wf.nChannels == 1) {

    //
    // Draw the x-axis
    //
    hbr = SelectObject(hdc, CreateSolidBrush(MONOBRUSH));
    y = rc.top + h/2;
    PatBlt(hdc, rc.left, y, w, 1, PATCOPY);

    //
    // 8 bit data is centred around 0x80
    //
    if (wf.wBitsPerSample == 8) {
        for (x=0; x<w; x++) {

        // which byte of audio data belongs at this pixel?
        b = *((HPBYTE)lpAudio + muldiv32(x, lLen, w));

        if (b > 0x80) {
            i = y - MulDiv(b - 0x80, (h / 2), 128);
            PatBlt(hdc, rc.left+x, i, 1, y-i, PATCOPY);
        }
        else {
            i = y + MulDiv(0x80 - b, (h / 2), 128);
            PatBlt(hdc, rc.left + x, y, 1, i - y, PATCOPY);
        }
        }
    }

    //
    // 16 bit data is centred around 0x00
    //
    else if (wf.wBitsPerSample == 16) {
        for (x=0; x<w; x++) {

        // which byte of audio data belongs at this pixel?
        // Don't make any assumptions about INT size !
        i = *((HPSHORT)lpAudio + muldiv32(x,lLen,w));

        if (i > 0) {
            i = y - (int) ((LONG)i * (h/2) / 32768);
            PatBlt(hdc, rc.left+x, i, 1, y-i, PATCOPY);
        }
        else {
            i = (int) ((LONG)i * (h/2) / 32768);
            PatBlt(hdc, rc.left+x, y, 1, -i, PATCOPY);
        }
        }
    }
    DeleteObject(SelectObject(hdc, hbr));
    } // endif mono

    //
    // Draw stereo waveform data
    //
    else if (wf.wf.nChannels == 2) {

    //
    // 8 bit data is centred around 0x80
    //
    if (wf.wBitsPerSample == 8) {

        // Left channel
        hbr = SelectObject(hdc, CreateSolidBrush(LEFTBRUSH));
        y = rc.top + h/4;
        PatBlt(hdc, rc.left, y, w, 1, PATCOPY);

        for (x=0; x<w; x++) {
        b = *((HPBYTE)lpAudio + muldiv32(x,lLen,w) * 2);

        if (b > 0x80) {
            i = y - MulDiv(b-0x80,(h/4),128);
            PatBlt(hdc, rc.left+x, i, 1, y-i, PATCOPY);
        }
        else {
            i = y + MulDiv(0x80-b,(h/4),128);
            PatBlt(hdc, rc.left+x, y, 1, i-y, PATCOPY);
        }
        }
        DeleteObject(SelectObject(hdc, hbr));

        // Right channel
        hbr = SelectObject(hdc, CreateSolidBrush(RIGHTBRUSH));
        y = rc.top + h * 3 / 4;
        PatBlt(hdc, rc.left, y, w, 1, PATCOPY);

        for (x=0; x<w; x++) {
        b = *((HPBYTE)lpAudio + muldiv32(x,lLen,w) * 2 + 1);

        if (b > 0x80) {
            i = y - MulDiv(b-0x80,(h/4),128);
            PatBlt(hdc, rc.left+x, i, 1, y-i, PATCOPY);
        }
        else {
            i = y + MulDiv(0x80-b,(h/4),128);
            PatBlt(hdc, rc.left+x, y, 1, i-y, PATCOPY);
        }
        }
        DeleteObject(SelectObject(hdc, hbr));
    }

    //
    // 16 bit data is centred around 0x00
    //
    else if (wf.wBitsPerSample == 16) {

        // Left channel
        hbr = SelectObject(hdc, CreateSolidBrush(LEFTBRUSH));
        y = rc.top + h/4;
        PatBlt(hdc, rc.left, y, w, 1, PATCOPY);

        for (x=0; x<w; x++) {

        // Don't make any assumptions about INT size !
        i = *((HPSHORT)lpAudio + muldiv32(x,lLen,w) * 2);
        if (i > 0) {
            i = y - (int) ((LONG)i * (h/4) / 32768);
            PatBlt(hdc, rc.left+x, i, 1, y-i, PATCOPY);
        }
        else {
            i = (int) ((LONG)i * (h/4) / 32768);
            PatBlt(hdc, rc.left+x, y, 1, -i, PATCOPY);
        }
        }
        DeleteObject(SelectObject(hdc, hbr));

        // Right channel
        hbr = SelectObject(hdc, CreateSolidBrush(RIGHTBRUSH));
        y = rc.top + h * 3 / 4;
        PatBlt(hdc, rc.left, y, w, 1, PATCOPY);

        for (x=0; x<w; x++) {
        // Don't make any assumptions about INT size !
        i = *((HPSHORT)lpAudio + muldiv32(x,lLen,w) * 2 + 1);
        if (i > 0) {
            i = y - (int) ((LONG)i * (h/4) / 32768);
            PatBlt(hdc, rc.left+x, i, 1, y-i, PATCOPY);
        }
        else {
            i = (int) ((LONG)i * (h/4) / 32768);
            PatBlt(hdc, rc.left+x, y, 1, -i, PATCOPY);
        }
        }
        DeleteObject(SelectObject(hdc, hbr));
    }
    } // endif stereo
}

/*----------------------------------------------------------------------------*\
|    PaintStuff()                                                               |
|    Do our painting.  Return the height of everything painted so we know how   |
|    much room it took to set our scrollbars.  If fDrawEverything is TRUE,      |
|    we will not stop drawing just because we know we're drawing outside the    |
|    window. This is used to determine how much we would want to draw.          |
\*----------------------------------------------------------------------------*/

int PaintStuff(HDC hdc, HWND hwnd, BOOL fDrawEverything)
{
    int         yStreamTop;
    char        szText[BUFSIZE];
    int         iFrameWidth, iLen;
    LONG        lSamp, lCurSamp;
    int         n;
    int         nFrames;
    LPBITMAPINFOHEADER lpbi = NULL;
    LONG        l;
    LONG        lTime;
    LONG        lSize = 0;
    LONG        lAudioStart;
    LONG        lAudioLen;
    RECT        rcFrame, rcC;
    int         i;
    HBRUSH      hbr, hbrOld;
    RECT        rc;

    GetClientRect(hwnd, &rcC);

    //
    // Look at scrollbars to find current position
    //
    lTime = GetScrollTime(hwnd);
    yStreamTop = -GetScrollPos(hwnd, SB_VERT);

    //
    // Walk through all streams and draw something
    //
    for (i=0; i<gcpavi; i++) {
    AVISTREAMINFO   avis;
    LONG            lEnd, lEndTime;
    COLORREF        nCol;

    //
    // Remember where this stream begins
    //
    gStreamTop[i] = yStreamTop + GetScrollPos(hwnd, SB_VERT);

    //
    // Get some info about this stream
    //
    AVIStreamInfo(gapavi[i], &avis, sizeof(avis));

    //
    // Highlight the stream name if we're supposed to
    //
    if (gSelectedStream == MAXNUMSTREAMS+i) {
        hbr = CreateSolidBrush(HIGHLIGHT);
        hbrOld = SelectObject(hdc, hbr);

        PatBlt(hdc, 0, yStreamTop, rcC.right, TSPACE * 2, PATCOPY);
        SelectObject(hdc, hbrOld);
        DeleteObject(hbr);
    }

    // First we'll print out the stream name
    nCol = SetBkColor(hdc, GetSysColor(COLOR_WINDOW));
    TextOut(hdc, HSPACE, yStreamTop, avis.szName, strlen(avis.szName));
    SetBkColor(hdc, nCol);

    // Skip to the next line
    yStreamTop += 2*TSPACE;

    if (galSelStart[i] == -1)
    {
        LoadString( ghInstApp, IDS_FORMAT_1, gszBuffer, BUFSIZE );
        iLen = wsprintf(szText,
                gszBuffer,
                i,
                (LPSTR) &avis.fccType,      // compressor FOURCC
                AVIStreamStart(gapavi[i]),
                AVIStreamLength(gapavi[i]),
                (AVIStreamEndTime(gapavi[i]) -
                 AVIStreamStartTime(gapavi[i])) / 1000);
    }
    else
    {
        LoadString( ghInstApp, IDS_FORMAT_2, gszBuffer, BUFSIZE );
        iLen = wsprintf(szText,
                gszBuffer,
                i,
                (LPSTR) &avis.fccType,      // compressor FOURCC
                AVIStreamStart(gapavi[i]),
                AVIStreamLength(gapavi[i]),
                (AVIStreamEndTime(gapavi[i]) -
                 AVIStreamStartTime(gapavi[i])) / 1000,
                galSelStart[i], galSelStart[i] + galSelLen[i] - 1);
    }
    //
    // Highlight the stream info if we're supposed to
    //
    if (gSelectedStream == i) {
        hbr = CreateSolidBrush(HIGHLIGHT);
        hbrOld = SelectObject(hdc, hbr);

        PatBlt(hdc, 0, yStreamTop, rcC.right, TSPACE * 2, PATCOPY);
        SelectObject(hdc, hbrOld);
        DeleteObject(hbr);
    }

    nCol = SetBkColor(hdc, GetSysColor(COLOR_WINDOW));
    TextOut(hdc, HSPACE, yStreamTop, szText, iLen);
    SetBkColor(hdc, nCol);

    yStreamTop += TSPACE;
    //
    // Draw a VIDEO stream
    //
    if (avis.fccType == streamtypeVIDEO) {
        if (gapgf[i] == NULL)
        continue;

        //
        // Which frame belongs at this time?
        //
        lEndTime = AVIStreamEndTime(gapavi[i]);
        if (lTime <= lEndTime)
        lSamp = AVIStreamTimeToSample(gapavi[i], lTime);
        else {      // we've scrolled past the end of this stream
        lEnd = AVIStreamEnd(gapavi[i]);
        lSamp = lEnd + AVIStreamTimeToSample(gapavi[i],
                             lTime - lEndTime);
        }

        //
        // how wide is each frame to paint?
        //
        iFrameWidth = (avis.rcFrame.right - avis.rcFrame.left) *
              gwZoom / 4 + HSPACE;

        //
        // how many frames can we fit on each half of the screen
        // not counting the one we'll centre?
        //
        nFrames = (rcC.right - iFrameWidth) / (2 * iFrameWidth);
        if (nFrames < 0)
        nFrames = 0;

        //
        // Step through all the frames we'll draw
        //
        for (n = -nFrames; n <= nFrames; n++) {

        //
        // Each video stream is drawn as a horizontal line of
        // frames, very close together.
        // The first video stream shows a different frame in
        // each square. Thus the scale of time is determined
        // by the first video stream.
        // Every other video stream shows whatever
        // frame belongs at the time corresponding to the mid-
        // point of each square.
        //
        if (i == giFirstVideo) {

            //
            // by definition, we know what frame we're drawing..
            // (lSamp-n), (lSamp-(n-1)), ..., (lSamp), ...,
            // (lSamp+n) (lSamp is the one in the centre)
            //
            lCurSamp = lSamp + n;

            //
            // what time is it at that frame? This number will
            // be printed underneath the frame
            //
            l = AVIStreamSampleToTime(gapavi[i], lCurSamp);

        } else {        // NOT the first video stream

            //
            // What time is it at the left hand of the square
            // we'll draw?  That's what frame we use.
            // Does the rounding with MulDiv32 have better properties
            // than muldiv32? It appears to give _slightly_ better performance

            l = lTime + MulDiv32(n * (iFrameWidth+HSPACE),
                     gdwMicroSecPerPixel, 1000);
            //if (n<=0) {  // calculate the time for a frame left of centre,
            //             // don't forget the HSPACE offset.
            //    l = lTime - muldiv32(-n * (iFrameWidth + HSPACE),
            //                         gdwMicroSecPerPixel, 1000);
            //
            //}
            //else { // frame is to right of centre.
            //    l = lTime + muldiv32(n * (iFrameWidth +HSPACE),
            //                           gdwMicroSecPerPixel, 1000);
            //
            //}

            //
            // What frame belongs to that time?
            //
            lCurSamp = AVIStreamTimeToSample(gapavi[i], l);

            //
            // Use the exact time of that frame when printing
            //
            l = AVIStreamSampleToTime(gapavi[i], lCurSamp);
        }

        // !!!
        // Could actually return an LPBI for invalid frames
        // so we better force it to NULL.
        //
        if (gapgf[i] && lCurSamp >= AVIStreamStart(gapavi[i])) // &&
            //lCurSamp <= AVIStreamEnd(gapavi[i]))
            lpbi = AVIStreamGetFrame(gapgf[i], lCurSamp);
        else
            lpbi = NULL;

        //
        // Figure out where to draw this frame
        //
        rcFrame.left   = rcC.right / 2 -
                 ((avis.rcFrame.right - avis.rcFrame.left) * gwZoom / 4)
                 / 2 + (n * iFrameWidth);
        rcFrame.top    = yStreamTop + TSPACE;
        rcFrame.right  = rcFrame.left +
                 (avis.rcFrame.right - avis.rcFrame.left) * gwZoom / 4;
        rcFrame.bottom = rcFrame.top +
                 (avis.rcFrame.bottom - avis.rcFrame.top) * gwZoom / 4;

        //
        // If this frame is selected, highlight it
        //
        if (lCurSamp >= galSelStart[i] &&
            lCurSamp < galSelStart[i] +
            galSelLen[i]) {
            hbr = CreateSolidBrush(HIGHLIGHT);
        }
        else { //not highlighted - but need to clear area around frame
               // of selection
            hbr = CreateSolidBrush(GetBkColor(hdc));
        }

        FrameVideo(hdc, &rcFrame, hbr);
        DeleteObject (hbr);

        //
        // draw a border around the centre frame.
        //
        if (n == 0) {
            hbr = CreateSolidBrush(RGB(255,0,0));
            InflateRect(&rcFrame, 1, 1);
            FrameRect(hdc, &rcFrame, hbr);
            InflateRect(&rcFrame, -1, -1);
            DeleteObject (hbr);
        }

        //
        // Now draw the video frame in the computed rectangle
        //
        PaintVideo(hdc, rcFrame, i, lpbi, lCurSamp, l);
        }

        //
        // Print a description of this stream
        //
        if (lpbi)
        AVIStreamSampleSize(gapavi[i], lSamp, &lSize);

        //
        // Move down to where we can draw the next stream
        //
        yStreamTop += TSPACE +
              (rcFrame.bottom - rcFrame.top) +
              TSPACE;
    }

    //
    // Draw an AUDIO stream
    //
    else if (avis.fccType == streamtypeAUDIO) {

        //
        // Figure out which samples are visible
        //
        lAudioStart = lTime - muldiv32(rcC.right / 2,
                       gdwMicroSecPerPixel, 1000);
        lAudioLen = 2 * (lTime - lAudioStart);

        // clear the selection area

        hbr = CreateSolidBrush(GetBkColor(hdc));
        hbrOld = SelectObject(hdc, hbr);
        PatBlt(hdc,
        0,
        yStreamTop + TSPACE - SELECTVSPACE,
        rcC.right,
        SELECTVSPACE,
        PATCOPY);
        PatBlt(hdc,
        0,
        yStreamTop + TSPACE + (AUDIOVSPACE * gwZoom/4),
        rcC.right,
        SELECTVSPACE,
        PATCOPY);
        SelectObject(hdc, hbrOld);
        DeleteObject (hbr);

        //
        // We have a selection... Highlight it
        //
        if (galSelStart[i] != -1) {
        LONG lSelSt, lSelLen;

        //
        // What time is our selection?
        //
        lSelSt = AVIStreamSampleToTime(gapavi[i], galSelStart[i]);
        lSelLen = AVIStreamSampleToTime(gapavi[i], galSelLen[i]);

        //
        // At what pixels is our selection?
        //
        if (lSelSt < lTime) { //selecting to the left of the current position
            rc.left = rcC.right /2 - (int)
            muldiv32((lTime - lSelSt) , 1000, gdwMicroSecPerPixel);
        }
        else {
            rc.left = rcC.right / 2 + (int)
            muldiv32(lSelSt - lTime, 1000, gdwMicroSecPerPixel);
        }
        rc.right = rc.left + (int)
            muldiv32(lSelLen, 1000, gdwMicroSecPerPixel);

        // Selection starts way past left side of screen
        if (lSelSt < lAudioStart)
            rc.left = 0;
        // Selection is off, screen left
        if (lSelSt + lSelLen < lAudioStart)
            rc.right = - SELECTVSPACE;

        // Selection is off, screen right
        if (lSelSt > lAudioStart + lAudioLen)
            rc.left = rcC.right + SELECTVSPACE;

        // Selection ends past the right side of the screen
        if (lSelSt + lSelLen > lAudioStart + lAudioLen)
            rc.right = rcC.right;
        if (rc.right == rc.left)        // draw SOMEthing.
            rc.right++;
        rc.top = yStreamTop + TSPACE;
        rc.bottom = rc.top + AUDIOVSPACE * gwZoom / 4;

        //
        // Draw some indication
        //
        hbr = CreateSolidBrush(HIGHLIGHT);
        hbrOld = SelectObject(hdc, hbr);
        PatBlt(hdc,
               rc.left - SELECTVSPACE,
               rc.top - SELECTVSPACE,
               rc.right - rc.left + 2 * SELECTVSPACE,
               SELECTVSPACE,
               PATCOPY);
        PatBlt(hdc,
               rc.left - SELECTVSPACE,
               rc.bottom,
               rc.right - rc.left + 2 * SELECTVSPACE,
               SELECTVSPACE,
               PATCOPY);
        SelectObject(hdc, hbrOld);
        DeleteObject (hbr);
        }

        //
        // Make the rectangle to draw audio into
        //
        rc.left = rcC.left;
        rc.right = rcC.right;
        rc.top = yStreamTop + TSPACE;
        rc.bottom = rc.top + AUDIOVSPACE * gwZoom / 4;

        //
        // Actually paint the audio
        //
        PaintAudio(hdc, &rc, gapavi[i], lAudioStart, lAudioLen);

        //
        // Print the time at the centre of the audio stream
        //
        iLen = wsprintf(szText, "%ld.%03lds", lTime/1000, lTime%1000);
        rc.left = (rc.right - rc.left) / 2 - 5 * HSPACE;
        rc.right = (rc.right - rc.left) / 2;
        rc.top = rc.bottom + HSPACE; rc.bottom = rc.top + VSPACE;
        nCol = SetBkColor(hdc, GetSysColor(COLOR_WINDOW));
        ExtTextOut(hdc, rc.left, rc.top, 0, &rc, szText, iLen, NULL);
        SetBkColor(hdc, nCol);

        //
        // Move down to where we can draw the next stream
        //
        yStreamTop += TSPACE + AUDIOVSPACE * gwZoom / 4;

    }

    yStreamTop += TSPACE + TSPACE;

    //
    // Give up once we're painting below the bottom of the window
    //
    if (!fDrawEverything && yStreamTop >= rcC.bottom)
        break;
    }

    // The bottom of all the streams;
    gStreamTop[gcpavi] = yStreamTop + GetScrollPos(hwnd, SB_VERT);

    //
    // How many lines did we draw?
    //
    return yStreamTop + GetScrollPos(hwnd, SB_VERT);
}

/*----------------------------------------------------------------------------*\
|    FixScrollBars()                                                            |
|    When we load a file or zoom changes, we re-set the scrollbars              |
\*----------------------------------------------------------------------------*/

void FixScrollbars(HWND hwnd)
{
    int                 nHeight = 0;
    RECT                rc;
    HDC                 hdc;

    //
    // Determine how tall our window needs to be to display everything.
    //
    hdc = GetDC(NULL);
    ExcludeClipRect(hdc, 0, 0, 32767, 32767);   // don't actually draw
    nHeight = PaintStuff(hdc, hwnd, TRUE);
    ReleaseDC(NULL, hdc);

    //
    // Set vertical scrollbar for scrolling the visible area
    //
    GetClientRect(hwnd, &rc);
    nVertHeight = nHeight;      // total height in pixels of entire display

    //
    // We won't fit in the window... need scrollbars
    //
    if (nHeight > rc.bottom)
    {
    nVertSBLen = nHeight - rc.bottom;
    SetScrollRange(hwnd, SB_VERT, 0, nVertSBLen, TRUE);
    SetScrollPos(hwnd, SB_VERT, 0, TRUE);

    //
    // We will fit in the window!  No scrollbars necessary
    //
    }
    else
    {
    nVertSBLen = 0;
    SetScrollRange(hwnd, SB_VERT, 0, 0, TRUE);
    }
    return;
}



/*----------------------------------------------------------------------------*\
|    InitStreams()                                                              |
|    Initialize the streams of a loaded file -- the compression options, the    |
|    DrawDIB handles, and the scroll bars.                                      |
|    !!! This clears the compression options right now every time it's called!  |
\*----------------------------------------------------------------------------*/

void InitStreams(HWND hwnd)
{
    AVISTREAMINFO     avis;
    LONG        lTemp;
    int         i;

    //
    // Start with bogus times
    //
    timeStart = 0x7FFFFFFF;
    timeEnd   = 0;

    //
    // Walk through and init all streams loaded
    //
    for (i = 0; i < gcpavi; i++) {

    AVIStreamInfo(gapavi[i], &avis, sizeof(avis));

    //
    // Save and SaveOptions code takes a pointer to our compression opts
    //
    galpAVIOptions[i] = &gaAVIOptions[i];

    //
    // clear options structure to zeroes
    //
    _fmemset(galpAVIOptions[i], 0, sizeof(AVICOMPRESSOPTIONS));

    //
    // Initialize the compression options to some default stuff
    // !!! Pick something better
    //
    galpAVIOptions[i]->fccType = avis.fccType;

    switch(avis.fccType) {

        case streamtypeVIDEO:
        galpAVIOptions[i]->dwFlags = AVICOMPRESSF_VALID |
                AVICOMPRESSF_KEYFRAMES | AVICOMPRESSF_DATARATE;
        galpAVIOptions[i]->fccHandler = 0;
        galpAVIOptions[i]->dwQuality = (DWORD)ICQUALITY_DEFAULT;
        galpAVIOptions[i]->dwKeyFrameEvery = (DWORD)-1; // Default
        galpAVIOptions[i]->dwBytesPerSecond = 0;
        galpAVIOptions[i]->dwInterleaveEvery = 1;
        break;

        case streamtypeAUDIO:
        galpAVIOptions[i]->dwFlags |= AVICOMPRESSF_VALID;
        galpAVIOptions[i]->dwInterleaveEvery = 1;
        AVIStreamReadFormat(gapavi[i],
                    AVIStreamStart(gapavi[i]),
                    NULL,
                    &lTemp);
        galpAVIOptions[i]->cbFormat = lTemp;
        if (lTemp)
            galpAVIOptions[i]->lpFormat = GlobalAllocPtr(GHND, lTemp);
        // Use current format as default format
        if (galpAVIOptions[i]->lpFormat)
            AVIStreamReadFormat(gapavi[i],
                    AVIStreamStart(gapavi[i]),
                    galpAVIOptions[i]->lpFormat,
                    &lTemp);
        break;

        default:
        break;
    }

    //
    // We're finding the earliest and latest start and end points for
    // our scrollbar.
    //
    timeStart = min(timeStart, AVIStreamStartTime(gapavi[i]));
    timeEnd   = max(timeEnd, AVIStreamEndTime(gapavi[i]));

    //
    // Initialize video streams for getting decompressed frames to display
    //
    if (avis.fccType == streamtypeVIDEO) {

        gapgf[i] = AVIStreamGetFrameOpen(gapavi[i], NULL);

        if (gapgf[i] == NULL)
        continue;

        ghdd[i] = DrawDibOpen();
        // !!! DrawDibBegin?

        if (!gfVideoFound) {
        DWORD        dw;

        //
        // Remember the first video stream --- treat it specially
        //
        giFirstVideo = i;

        //
        // Set the horizontal scrollbar scale to show every frame
        // of the first video stream exactly once
        //
        dw = (avis.rcFrame.right - avis.rcFrame.left) * gwZoom / 4 + HSPACE;

        gdwMicroSecPerPixel = muldiv32(1000000,
                           avis.dwScale,
                           dw * avis.dwRate);
        // Move one frame on the top video screen for each HSCROLL
        timehscroll = muldiv32(1000, avis.dwScale, avis.dwRate);
        }

    } else if (avis.fccType == streamtypeAUDIO) {

        // These aren't used and better be NULL!
        gapgf[i] = ghdd[i] = NULL;

        //
        // If there are no video streams, we base everything on this
        // audio stream.
        //
        if (!gfAudioFound && !gfVideoFound) {

        // Show one sample per pixel
        gdwMicroSecPerPixel = muldiv32(1000000,
                           avis.dwScale,
                           avis.dwRate);
        // Move one sample per HSCROLL
        // Move at least enough to show movement
        timehscroll = muldiv32(1000, avis.dwScale, avis.dwRate);
        }

        //
        // Remember the first audio stream --- treat it specially
        //
        if (!gfAudioFound)
        giFirstAudio = i;

    }

    }

    timeLength = timeEnd - timeStart;

    if (timeLength == 0)
    timeLength = 1;

    // Make sure HSCROLL scrolls enough to be noticeable.
    timehscroll = max(timehscroll, timeLength / SCROLLRANGE + 2);

    SetScrollRange(hwnd, SB_HORZ, 0, SCROLLRANGE, TRUE);
    SetScrollTime(hwnd, timeStart);

    FixScrollbars(hwnd);
}


/*----------------------------------------------------------------------------*\
|    FixWindowTitle()                                                           |
|    Update the window title to reflect what's loaded                           |
\*----------------------------------------------------------------------------*/

void FixWindowTitle(HWND hwnd)
{
    char szTitle[2*BUFSIZE];

    LoadString( ghInstApp, IDS_APPNAME, gszBuffer, BUFSIZE );

    wsprintf(szTitle, "%s %s", (LPSTR)gszBuffer, (LPSTR)gszFileName);

    SetWindowText( hwnd, szTitle );

    InvalidateRect(hwnd, NULL, TRUE);
}

/*----------------------------------------------------------------------------*\
|    FreeDrawStuff()                                                            |
|    Free up the resources associated with DrawDIB.                             |
\*----------------------------------------------------------------------------*/

void FreeDrawStuff(HWND hwnd)
{
    int i;

    // Make sure we're not playing!
    aviaudioStop();

    for (i = 0; i < gcpavi; i++) {
    if (gapgf[i]) {
        AVIStreamGetFrameClose(gapgf[i]);
        gapgf[i] = NULL;
    }
    if (ghdd[i]) {
        DrawDibClose(ghdd[i]);
        ghdd[i] = 0;
    }
    }
    SetScrollRange(hwnd, SB_HORZ, 0, 0, TRUE);
    giFirstVideo = giFirstAudio = -1;
}


/*----------------------------------------------------------------------------*\
|    NukeAVIStream()                                                            |
|    Get rid of a stream in our array and compact it.                           |
\*----------------------------------------------------------------------------*/

void NukeAVIStream(int i)
{
    int j;

    //
    // Make sure it's a real stream number
    //
    if (i < 0 || i >=gcpavi)
    return;

    //
    // Free all the resources associated with this stream
    //
    AVIStreamRelease(gapavi[i]);
    if (galpAVIOptions[i]->lpFormat) {
    GlobalFreePtr(galpAVIOptions[i]->lpFormat);
    }
    if (gapgf[i]) {
    AVIStreamGetFrameClose(gapgf[i]);
    gapgf[i] = NULL;
    }
    if (ghdd[i]) {
    DrawDibClose(ghdd[i]);
    ghdd[i] = 0;
    }

    //
    // Compact the arrays of junk
    //
    for (j = i; j < gcpavi - 1; j++) {
    gapavi[j] = gapavi[j+1];
    galpAVIOptions[j] = galpAVIOptions[j+1];
    gapgf[j] = gapgf[j+1];
    ghdd[j] = ghdd[j+1];
    }

    gcpavi--;
}

/*----------------------------------------------------------------------------*\
|    FreeAVI()                                                                  |
|    Free the resources associated with an open file.                           |
\*----------------------------------------------------------------------------*/

void FreeAvi(HWND hwnd)
{
    int i;

    FreeDrawStuff(hwnd);

    AVISaveOptionsFree(gcpavi, galpAVIOptions);

    for (i = 0; i < gcpavi; i++) {
    AVIStreamRelease(gapavi[i]);
    }

    // Good a place as any to make sure audio data gets freed
    if (lpAudio)
    GlobalFreePtr(lpAudio);
    lpAudio = NULL;

    gcpavi = 0;
}

/*----------------------------------------------------------------------------*\
|    InsertAVIFile()                                                            |
|    Put a new AVI file into our internal structures.                           |
\*----------------------------------------------------------------------------*/

void InsertAVIFile(PAVIFILE pfile, HWND hwnd, LPSTR lpszFile)
{
    int         i;
    PAVISTREAM  pavi;

    for (i = gcpavi; i <= MAXNUMSTREAMS; i++) {
    if (AVIFileGetStream(pfile, &pavi, 0L, i - gcpavi) != AVIERR_OK)
        break;
    if (i == MAXNUMSTREAMS)
    {
        AVIStreamRelease(pavi);
        LoadString( ghInstApp, IDS_MAXSTREAMS, gszBuffer, BUFSIZE );
        ErrMsg(gszBuffer);
        break;
    }
    if (CreateEditableStream(&gapavi[i], pavi) != AVIERR_OK) {
        AVIStreamRelease(pavi);
        break;
    }
    AVIStreamRelease(pavi);
    galSelStart[i] = galSelLen[i] = -1;
    }

    AVIFileRelease(pfile);

    if (gcpavi == i && i != MAXNUMSTREAMS)
    {

    LoadString( ghInstApp, IDS_NOOPEN, gszBuffer, BUFSIZE );

    ErrMsg(gszBuffer, lpszFile);
    return;
    }

    FreeDrawStuff(hwnd);
    gcpavi = i;
    InitStreams(hwnd);
    FixWindowTitle(hwnd);
}


/*----------------------------------------------------------------------------*\
|    InitAVI()                                                                  |
|    Open up a file through the AVIFile handlers.                               |
\*----------------------------------------------------------------------------*/


void InitAvi(HWND hwnd, LPSTR szFile, int nMenu)
{
    HRESULT     hr;
    PAVIFILE    pfile;

    hr = AVIFileOpen(&pfile, szFile, 0, 0L);

    if (hr != 0)
    {
    LoadString( ghInstApp, IDS_NOOPEN, gszBuffer, BUFSIZE );
    ErrMsg(gszBuffer, szFile);
    return;
    }

    //
    // If we're opening something new, close other open files, otherwise
    // just close the draw stuff so we'll merge streams with the new file
    //
    if (nMenu == MENU_OPEN)
    FreeAvi(hwnd);

    InsertAVIFile(pfile, hwnd, szFile);
}

/*----------------------------------------------------------------------------*\
|    DropAvi()                                                                  |
|    Allow a drag/drop on AVIEdit.                                              |
\*----------------------------------------------------------------------------*/
void DropAvi(HWND hwnd, HDROP hDrop)
{
    char        szPath[BUFSIZE];
    UINT        nDropped, n;
    PAVIFILE    pfile;
    HRESULT     hr;

    // Get number of files dropped
    nDropped = DragQueryFile(hDrop,0xFFFF,NULL,0);

    if (nDropped) {
    SetActiveWindow(hwnd);

    // If we wanted to, we could simulate a click at the position
    // the drop took place....

    for (n = 0; n < nDropped; n++) {
        // Get the file that was dropped....
        DragQueryFile(hDrop, n, szPath, BUFSIZE);

        hr = AVIFileOpen(&pfile, szPath, 0, 0L);

        if (hr == 0) {
        // ... and paste it in.
        editPaste(hwnd, pfile);
        }
    }
    }
    DragFinish(hDrop);     /* Delete structure alocated */
}

/*----------------------------------------------------------------------------*\
|   AppInit( hInst, hPrev)                                                     |
|                                                                              |
|   Description:                                                               |
|       This is called when the application is first loaded into               |
|       memory.  It performs all initialization that doesn't need to be done   |
|       once per instance.                                                     |
|                                                                              |
|   Arguments:                                                                 |
|       hInstance       instance handle of current instance                    |
|       hPrev           instance handle of previous instance                   |
|                                                                              |
|   Returns:                                                                   |
|       TRUE if successful, FALSE if not                                       |
|                                                                              |
\*----------------------------------------------------------------------------*/

BOOL AppInit(HINSTANCE hInst, HINSTANCE hPrev, int sw, LPSTR szCmdLine)
{
    WNDCLASS cls;
    WORD        wVer;

    /* first let's make sure we are running on 1.1 */
    wVer = HIWORD(VideoForWindowsVersion());
    if (wVer < 0x010a)
    {
    char szTitle[BUFSIZE];
    /* oops, we are too old, blow out of here */
    MessageBeep(MB_ICONHAND);
    LoadString( ghInstApp, IDS_APPERR, szTitle, BUFSIZE );
    LoadString( ghInstApp, IDS_OLDVFW, gszBuffer, BUFSIZE );

    MessageBox(NULL, gszBuffer, szTitle, MB_OK|MB_ICONSTOP);
    return FALSE;
    }

    //
    // Save instance handle for DialogBoxs
    //
    ghInstApp = hInst;

    ghAccel = LoadAccelerators(hInst, MAKEINTATOM(ID_APP));

    //
    // Did we get passed a filename on the command line? We'll open it at create
    // time.
    //
    if (szCmdLine && szCmdLine[0])
    lstrcpy(gszFileName, szCmdLine);
    else
    lstrcpy( gszFileName, "" );

    lstrcpy( gszSaveFileName, "" );

    if (!hPrev) {
    /*
     *  Register a class for the main application window
     */
    cls.hCursor        = LoadCursor(NULL,IDC_ARROW);
    cls.hIcon          = LoadIcon(hInst,MAKEINTATOM(ID_APP));
    cls.lpszMenuName   = MAKEINTATOM(ID_APP);
    cls.lpszClassName  = MAKEINTATOM(ID_APP);
    cls.hbrBackground  = (HBRUSH)(COLOR_WINDOW + 1);
    cls.hInstance      = hInst;
    cls.style          = CS_BYTEALIGNCLIENT | CS_VREDRAW | CS_HREDRAW |
                 CS_DBLCLKS;
    cls.lpfnWndProc    = (WNDPROC)AppWndProc;
    cls.cbWndExtra     = 0;
    cls.cbClsExtra     = 0;

    if (!RegisterClass(&cls))
        return FALSE;
    }

    //
    // Must be called before using any of the AVIFile routines
    //
    AVIFileInit();

    LoadString( ghInstApp, IDS_APPNAME, gszBuffer, BUFSIZE );
    //
    // Create our main application window
    //
    ghwndApp = CreateWindow (
                 MAKEINTATOM(ID_APP),    // Class name
                 gszBuffer,             // Caption
                 WS_OVERLAPPEDWINDOW,    // Style bits
                 CW_USEDEFAULT, 0,       // Position
                 320,300,                // Size
                 (HWND)NULL,             // Parent window (no parent)
                 (HMENU)NULL,            // use class menu
                 hInst,                  // handle to window instance
                 (LPSTR)NULL             // no params to pass on
                 );
    ShowWindow(ghwndApp,sw);

    return TRUE;
}

/*----------------------------------------------------------------------------*\
|   WinMain( hInst, hPrev, lpszCmdLine, cmdShow )                              |
|                                                                              |
|   Description:                                                               |
|       The main procedure for the App.  After initializing, it just goes      |
|       into a message-processing loop until it gets a WM_QUIT message         |
|       (meaning the app was closed). If the preview is playing it adjusts     |
|       the scrollbar appropriately.                                           |
|                                                                              |
|   Arguments:                                                                 |
|       hInst           instance handle of this instance of the app            |
|       hPrev           instance handle of previous instance, NULL if first    |
|       szCmdLine       ->null-terminated command line                         |
|       cmdShow         specifies how the window is initially displayed        |
|                                                                              |
|   Returns:                                                                   |
|       The exit code as specified in the WM_QUIT message.                     |
|                                                                              |
\*----------------------------------------------------------------------------*/
int PASCAL WinMain(HINSTANCE hInst, HINSTANCE hPrev, LPSTR szCmdLine, int sw)
{
    MSG     msg;

    //
    // Call our initialization procedure
    //
    if (!AppInit(hInst, hPrev, sw, szCmdLine))
    return FALSE;

    /*
     * Polling messages from event queue
     */
    for (;;)
    {
    while (PeekMessage(&msg, NULL, 0, 0, PM_REMOVE))
    {
        if (msg.message == WM_QUIT)
        return msg.wParam;

        if (TranslateAccelerator(ghwndApp, ghAccel, &msg))
        continue;

        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }

    //
    // If we have no messages to dispatch, we do our background task...
    // If we're playing a file, we set the scroll bar to show the video
    // frames corresponding with the current playing audio sample
    //
    if (gfPlaying) {
        LONG    l;

        //
        // Use the audio clock to tell how long we've been playing.  To
        // maintain sync, it's important we use this clock.
        //
        l = aviaudioTime();         // returns -1 if no audio playing

        //
        // If we can't use the audio clock to tell us how long we've been
        // playing, calculate it ourself
        //
        if (l == -1)
        l = timeGetTime() - glPlayStartTime + glPlayStartPos;

        if (l != (LONG)GetScrollTime(ghwndApp)) {
        if (l < timeStart)      // make sure number isn't out of bounds
            l = timeStart;
        if (l > timeEnd)        // looks like we're all done!
            FORWARD_WM_COMMAND(ghwndApp, MENU_STOP, NULL, 0, SendMessage);

        SetScrollTime(ghwndApp, l);
        InvalidateRect(ghwndApp, NULL, FALSE);
        UpdateWindow(ghwndApp);

        continue;
        }
    }

    WaitMessage();
    }

    /* NOT REACHED */
}

/*----------------------------------------------------------------------------*\
|    SelectStream()                                                             |
|                                                                               |
|    Selects a portion of a stream i:                                           |
|                                                                               |
|    i == -1 means clear all selections                                         |
|    start == -1 means clear that individual stream's selection                 |
|    fAdd == TRUE means extend that stream's selection to include the new       |
|            range (will otherwise just replace the selection)                  |
|    fAll == TRUE means select this range in every stream, not just i           |
\*----------------------------------------------------------------------------*/

void SelectStream(HWND hwnd, int i, LONG start, LONG length, BOOL fAdd, BOOL fAll)
{
    int n, j;
    LONG mystart, mylength;
    RECT rc;

    //
    // Clear all selections
    //
    if (i == -1) {
    for (n = 0; n < gcpavi; n++)
        galSelStart[n] = galSelLen[n] = -1;

    } else if (i >= 0 && i < gcpavi) {  // valid stream number

    //
    // We've been told to clear this selection
    //
    if (start == -1 || length == -1)
        galSelStart[i] = galSelLen[i] = -1;

    //
    // Is this a valid selection range?
    //
    if (start >=AVIStreamStart(gapavi[i]) &&
        start < AVIStreamEnd(gapavi[i]) &&
        length >= 1) {

        //
        // Do we select the same range in every stream or just one?
        //
        for (j = (fAll ? 0 : i); j < (fAll ? gcpavi : i+1); j++) {

        //
        // Translate for each stream the equivalent region to select
        //
        if (j == i) {
            mystart = start; mylength = length;
        } else {
            mystart = AVIStreamSampleToSample(gapavi[j],
                              gapavi[i], start);
            mylength = max(1, AVIStreamSampleToSample(gapavi[j],
                                  gapavi[i], length));    // at least 1
            // !!! Better invalidate this entire stream since we're not
            // sure what part needs repainting.
            GetClientRect(hwnd, &rc);
            rc.top = gStreamTop[j] - GetScrollPos(hwnd, SB_VERT);
            rc.bottom = gStreamTop[j+1] - GetScrollPos(hwnd, SB_VERT);
            InvalidateRect(hwnd, &rc, FALSE);
        }

        //
        // Verify we got good selection values
        //
        if (mystart < AVIStreamStart(gapavi[j])) {
            mylength -= AVIStreamStart(gapavi[j]) - mystart;
            mystart = AVIStreamStart(gapavi[j]);
        }
        if (mystart + mylength > AVIStreamEnd(gapavi[j]))
            mylength -= mystart + mylength - AVIStreamEnd(gapavi[j]);
        if (mylength <= 0)
            mystart = -1;
        if (mystart == -1)      // nothing to select in this stream
            continue;

        //
        // Reset selection to new values
        //
        if (!fAdd || galSelStart[j] == -1) {
            galSelStart[j] = mystart;
            galSelLen[j] = mylength;

            //
            // extend selection to include this new range
            //
        } else {
            if (mystart < galSelStart[j]) {
            galSelLen[j] += galSelStart[j] - mystart;
            galSelStart[j] = mystart;
            }
            if (mystart + mylength > galSelStart[j] + galSelLen[j])
            galSelLen[j] = mystart + mylength - galSelStart[j];
        }
        }
    }
    }
}

/*----------------------------------------------------------------------------*\
|    EditStreamName()                                                           |
|                                                                               |
|    We need to edit the name of a stream. Create the edit box.                 |
\*----------------------------------------------------------------------------*/

void EditStreamName(HWND hwndParent)

{
    AVISTREAMINFO avis;

    // Get the stream info so we can get the name
    AVIStreamInfo(gapavi[gSelectedStream-MAXNUMSTREAMS], &avis, sizeof(avis));

    // Create the window;
    InflateRect(&grcSelectedStream, 0, 2);
    ghwndEdit = CreateWindow(AVI_EDIT_CLASS, NULL,
                 WS_CHILD | WS_VISIBLE | WS_BORDER | ES_AUTOHSCROLL,
                 grcSelectedStream.left,
                 grcSelectedStream.top,
                 grcSelectedStream.right - grcSelectedStream.left,
                 grcSelectedStream.bottom - grcSelectedStream.top,
                 hwndParent, (HMENU)1, ghInstApp, NULL);

    // Subclass the window so we can trap <cr> hits.
    gOldEditProc = (WNDPROC)GetWindowLong(ghwndEdit, GWL_WNDPROC);
    SetWindowLong(ghwndEdit, GWL_WNDPROC, (long)NewEditProc);

    // Set the initial text of the edit window, give focus to the
    // window and select the text.
    SetWindowText(ghwndEdit, avis.szName);
    SetFocus(ghwndEdit);
    Edit_SetSel(ghwndEdit, 0, lstrlen(avis.szName));
}

/*----------------------------------------------------------------------------*\
|    EditDone()                                                                 |
|                                                                               |
|    Done with an edit. See if we take the changes.                             |
\*----------------------------------------------------------------------------*/

void EditDone(HWND hwndParent, BOOL bAcceptChange)
{
    // Update the stream name if we're supposed to.
    if (bAcceptChange) {
    char szBuff[BUFSIZE];
    int n;

    // Get the edited name and put into the stream header
    n = GetWindowText(ghwndEdit, szBuff, BUFSIZE);
    szBuff[n] = '\0';
    EditStreamSetName(gapavi[gSelectedStream-MAXNUMSTREAMS], szBuff);
    }

    // Turn the selection off.
    gSelectedStream = -1;

    // Nuke the edit window.
    SetWindowLong(ghwndEdit, GWL_WNDPROC, (long)gOldEditProc);
    DestroyWindow(ghwndEdit);
    ghwndEdit = NULL;

    // Paint where window used to be.
    InvalidateRect(hwndParent, &grcSelectedStream, TRUE);
    UpdateWindow(hwndParent);

    // Give the parent the focus back.
    SetFocus(hwndParent);
}

/*----------------------------------------------------------------------------*\
|    NewEditProc()                                                              |
|                                                                               |
|    Our own home-rolled window proc for the edit window giving                 |
|    notification when <cr> is hit.                                             |
|                                                                               |
|    We trap WM_CHAR, because WM_CHAR(wParam='\r') causes a beep, which         |
|    we don't want.                                                             |
\*----------------------------------------------------------------------------*/
#define _ANSI_R    (TCHAR)'\r'
LRESULT CALLBACK NewEditProc( HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam )
{
    switch (msg) {
    case WM_CHAR:
        // Trap a keydown for <cr>
        if (wParam == _ANSI_R) {
        // Send message to parent giving ID 2 (which doesn't
        // exist)
            FORWARD_WM_COMMAND(GetParent(hwnd), 2, NULL, 0, PostMessage);
        return 0L;
        }

        // Need normal handling of characters otherwise
        goto callDWP;

    case WM_KEYUP:
        // Trap a keydown for <Esc>. This is how we get out without
        // making a modification.
        if (wParam == VK_ESCAPE) {
        // Send message to parent giving ID 3 (which doesn't
        // exist)
            FORWARD_WM_COMMAND(GetParent(hwnd), 3, NULL, 0, PostMessage);
        return 0L;
        }

        // We want to fall through so what should happen on keydown
        // does.

    default:
callDWP:
        // Just call the old window proc
        return CallWindowProc(gOldEditProc, hwnd, msg, wParam, lParam);
    }
}

// ******************************************************************************
//
//      Message Handler for WM_CREATE
//
// ******************************************************************************

BOOL App_OnCreate(HWND hwnd, LPCREATESTRUCT lpCreateStruct)
{
    DragAcceptFiles(hwnd, TRUE);

    if (gszFileName[0])
    InitAvi(hwnd, gszFileName, MENU_OPEN);

    return TRUE;
}

// ******************************************************************************
//
//      Message Handler for WM_COMMAND
//
// ******************************************************************************

void App_OnCommand(HWND hwnd, int id, HWND hwndCtl, UINT codeNotify)
{
    if (id == 2)
    EditDone(hwnd, TRUE);
    // See if we are terminating editting.
    else if (id == 3)
    EditDone(hwnd, FALSE);
    else
    MenuHandler( hwnd, id );
}

// ******************************************************************************
//
//      Message Handler for WM_DROPFILES
//
// ******************************************************************************
//
void App_OnDropFiles(HWND hwnd, HDROP hdrop)
{
    DropAvi(hwnd, hdrop);

    return;
}

// ******************************************************************************
//
//      Message Handler for WM_INITMENU
//
// ******************************************************************************
void App_OnInitMenu(HWND hwnd, HMENU hMenu)
{
    int i;
    BOOL f;
    PAVIFILE pf;

    f = gcpavi > 0;
    EnableMenuItem(hMenu, MENU_SAVEAS, f ? MF_ENABLED : MF_GRAYED);
    EnableMenuItem(hMenu, MENU_OPTIONS,f ? MF_ENABLED : MF_GRAYED);

    EnableMenuItem(hMenu, MENU_CLOSE,  f ? MF_ENABLED : MF_GRAYED);
    EnableMenuItem(hMenu, MENU_MERGE,  f ? MF_ENABLED : MF_GRAYED);

    EnableMenuItem(hMenu, MENU_SETINFO,  f ? MF_ENABLED : MF_GRAYED);

    // !!! Why not provide UNDO while I'm at it?
    // Enable CUT/COPY/DELETE if there's something selected in a stream
    f = FALSE;
    for (i=0; i<gcpavi; i++)
    if (galSelStart[i] != -1)
        f = TRUE;

    EnableMenuItem(hMenu, MENU_COPY,   f ? MF_ENABLED : MF_GRAYED);
    EnableMenuItem(hMenu, MENU_CUT,    f ? MF_ENABLED : MF_GRAYED);
    EnableMenuItem(hMenu, MENU_DELETE, f ? MF_ENABLED : MF_GRAYED);

    // If we haven't an edit window, we need to setup the "Name'
    //
    if (ghwndEdit == NULL)
    {
    LoadString( ghInstApp, IDS_NAME, gszBuffer, BUFSIZE );
    ModifyMenu(hMenu, MENU_NAME, MF_BYCOMMAND | MF_STRING, MENU_NAME, gszBuffer);
    EnableMenuItem(hMenu, MENU_NAME,
               (gSelectedStream >= MAXNUMSTREAMS) ? MF_ENABLED : MF_GRAYED);
    }
    else
    {
    LoadString( ghInstApp, IDS_ABORTNAME, gszBuffer, BUFSIZE );
    ModifyMenu(hMenu, MENU_NAME, MF_BYCOMMAND | MF_STRING,MENU_NAME, gszBuffer);
    EnableMenuItem(hMenu, MENU_NAME,MF_ENABLED);
    }

    // See if there's anything to paste....
    f = FALSE;
    AVIGetFromClipboard(&pf);

    if (pf)
    {
    f = TRUE;
    AVIFileRelease(pf);
    }

    EnableMenuItem(hMenu, MENU_PASTE,  f ? MF_ENABLED : MF_GRAYED);

    f = gfAudioFound | gfVideoFound;
    EnableMenuItem(hMenu, MENU_PREVIEW, (f & !gfPlaying) ? MF_ENABLED : MF_GRAYED);
    EnableMenuItem(hMenu, MENU_STOP,    (f & gfPlaying)  ? MF_ENABLED : MF_GRAYED);

    CheckMenuItem(hMenu, MENU_ZOOMQUARTER, (gwZoom == 1)  ? MF_CHECKED : MF_UNCHECKED);
    CheckMenuItem(hMenu, MENU_ZOOMHALF,    (gwZoom == 2)  ? MF_CHECKED : MF_UNCHECKED);
    CheckMenuItem(hMenu, MENU_ZOOM1,       (gwZoom == 4)  ? MF_CHECKED : MF_UNCHECKED);
    CheckMenuItem(hMenu, MENU_ZOOM2,       (gwZoom == 8)  ? MF_CHECKED : MF_UNCHECKED);
    CheckMenuItem(hMenu, MENU_ZOOM4,       (gwZoom == 16) ? MF_CHECKED : MF_UNCHECKED);


    return;
}
// ******************************************************************************
//
//      Message Handler for WM_SIZE
//
// ******************************************************************************

void App_OnSize(HWND hwnd, UINT state, int cx, int cy)
{
    RECT rc;

    GetClientRect(hwnd, &rc);
    //
    // There is not enough vertical room to show all streams. Scrollbars
    // are required.
    //
    if (nVertHeight > rc.bottom)
    {
    nVertSBLen = nVertHeight - rc.bottom;
    SetScrollRange(hwnd, SB_VERT, 0, nVertSBLen, TRUE);
    }
    else// Everything fits vertically. No scrollbar necessary.
    {
    nVertSBLen = 0;
    SetScrollRange(hwnd, SB_VERT, 0, 0, TRUE);
    }
    return;
}
// ******************************************************************************
//
//      Message Handler for WM_DESTROY
//
// ******************************************************************************
//
void App_OnDestroy(HWND hwnd)
{
    AVIClearClipboard();
    FreeAvi(hwnd);      // close all open streams
    AVIFileExit();      // shuts down the AVIFile system
    PostQuitMessage(0);

    return;
}
// ******************************************************************************
//
//      Message Handler for WM_ENDSESSION
//
// ******************************************************************************
//
void App_OnEndSession(HWND hwnd, BOOL fEnding)
{
    if (fEnding)
    {
    if (GetClipboardOwner() == hwnd)
    {
        if (OpenClipboard(hwnd))
        {
        EmptyClipboard();
        CloseClipboard();
        }
    }
    FreeAvi(hwnd);
    }
    return;
}
// ******************************************************************************
//
//      Message Handler for WM_PALETTECHANGED
//
// ******************************************************************************
//
void App_OnPaletteChanged(HWND hwnd, HWND hwndPaletteChange)
{
    // It came from us.  Ignore it
    if (hwndPaletteChange == hwnd)
    return;

    //if needed, insert any calls - such as RealizePallete - below

    return;
}
// ******************************************************************************
//
//      Message Handler for WM_KEYDOWN
//
// ******************************************************************************
//
void App_OnKey(HWND hwnd, UINT vk, BOOL fDown, int cRepeat, UINT flags)
{
    if(fDown)
    {
    switch (vk)
    {
        case VK_UP:
        FORWARD_WM_VSCROLL(hwnd, NULL, SB_LINEUP, 0, PostMessage);
        break;
        case VK_DOWN:
        FORWARD_WM_VSCROLL(hwnd, NULL, SB_LINEDOWN, 0, PostMessage);
        break;
        case VK_PRIOR:
        FORWARD_WM_HSCROLL(hwnd, NULL, SB_PAGEUP, 0, PostMessage);
        break;
        case VK_NEXT:
        FORWARD_WM_HSCROLL(hwnd, NULL, SB_PAGEDOWN, 0, PostMessage);
        break;
        case VK_HOME:
        FORWARD_WM_HSCROLL(hwnd, NULL, SB_THUMBPOSITION, 0, PostMessage);
        break;
        case VK_END:
        FORWARD_WM_HSCROLL(hwnd, NULL, SB_THUMBPOSITION, 0x7FFF, PostMessage);
        break;
        case VK_LEFT:
        FORWARD_WM_HSCROLL(hwnd, NULL, SB_LINEUP, 0, PostMessage);
        break;
        case VK_RIGHT:
        FORWARD_WM_HSCROLL(hwnd, NULL, SB_LINEDOWN, 0, PostMessage);
        break;
    }
    }
    return;
}
// ******************************************************************************
//
//      Message Handler for WM_HSCROLL
//
// ******************************************************************************
//
void App_OnHScroll(HWND hwnd, HWND hwndCtl, UINT code, int pos)
{
    LONG lScrollTime;

    lScrollTime = GetScrollTime(hwnd);

    switch (code)
    {
    case SB_LINEDOWN:
        lScrollTime += timehscroll;
        break;
    case SB_LINEUP:
        lScrollTime -= timehscroll;
        break;
    case SB_PAGEDOWN:
        lScrollTime += timeLength/10;
        break;
    case SB_PAGEUP:
        lScrollTime -= timeLength/10;
        break;
    case SB_THUMBTRACK:
    case SB_THUMBPOSITION:
        lScrollTime = pos;
        lScrollTime = timeStart + muldiv32(lScrollTime, timeLength, SCROLLRANGE);
        break;
    }

    if (lScrollTime < timeStart)
    lScrollTime = timeStart;

    if (lScrollTime > timeEnd)
    lScrollTime = timeEnd;

    if (lScrollTime == (LONG)GetScrollTime(hwnd))
    return;

    SetScrollTime(hwnd, lScrollTime);
    InvalidateRect(hwnd, NULL, TRUE);
    UpdateWindow(hwnd);

    return;
}
// ******************************************************************************
//
//      Message Handler for WM_VSCROLL
//
// ******************************************************************************
//
void App_OnVScroll(HWND hwnd, HWND hwndCtl, UINT code, int pos)
{
    int nScrollPos;
    RECT rc;

    nScrollPos = GetScrollPos(hwnd, SB_VERT);

    GetClientRect(hwnd, &rc);

    switch (code)
    {
    case SB_LINEDOWN:
        nScrollPos += 10;
        break;
    case SB_LINEUP:
        nScrollPos -= 10;
        break;
    case SB_PAGEDOWN:
        nScrollPos += rc.bottom;
        break;
    case SB_PAGEUP:
        nScrollPos -= rc.bottom;
        break;
    case SB_THUMBTRACK:
    case SB_THUMBPOSITION:
        nScrollPos = pos;
        break;
    }

    if (nScrollPos < 0)
    nScrollPos = 0;

    if (nScrollPos > nVertSBLen)
    nScrollPos = nVertSBLen;

    if (nScrollPos == GetScrollPos(hwnd, SB_VERT))
    return;

    SetScrollPos(hwnd, SB_VERT, nScrollPos, TRUE);
    InvalidateRect(hwnd, NULL, TRUE);
    UpdateWindow(hwnd);

    return;
}
// ******************************************************************************
//
//      Message Handler for WM_RBUTTONDOWN
//
// ******************************************************************************
//
void App_OnRButtonDown(HWND hwnd, BOOL fDoubleClick, int x, int y, UINT keyFlags)
{
    RECT rc;
    int i;
    // Invalidate any stream that has something selected.  It needs
    // to redraw now.
    if (gSelectedStream >= MAXNUMSTREAMS) {
    if (ghwndEdit)
        EditDone(hwnd, FALSE);
    else {
        InvalidateRect(hwnd, &grcSelectedStream, TRUE); // needs to erase
        gSelectedStream = -1;
    }
    }
    else {
    GetClientRect(hwnd, &rc);
    for (i = 0; i < gcpavi; i++) {
         if (galSelStart[i] != -1) {
        rc.top = gStreamTop[i] - GetScrollPos(hwnd, SB_VERT);
        rc.bottom =gStreamTop[i+1] -GetScrollPos(hwnd, SB_VERT);
        InvalidateRect(hwnd, &rc, TRUE); // needs to erase
        }
    }

    // Deselect everything
    SelectStream(hwnd, -1, -1, -1, FALSE, FALSE);
    }
    return;
}
// ******************************************************************************
//
//      Message Handler for WM_LBUTTONDOWN
//
// ******************************************************************************
//
void App_OnLButtonDown(HWND hwnd, BOOL fDoubleClick, int x, int y, UINT keyFlags)
{
    int yTop, yBottom = 0, iFrameWidth, nFrames;
    int i,j,n;
    AVISTREAMINFO       avis;
    BOOL fShift = FALSE;
    BOOL fCtrl = FALSE;
    RECT rc, rcC;
    LONG        l, lTime, lSamp, lCurSamp;

    if( fDoubleClick ) {
    // See if we get to edit a stream name
    if (gSelectedStream >= MAXNUMSTREAMS)
        EditStreamName(hwnd);

    return;
    }

    GetClientRect(hwnd, &rc);
    rcC = rc;
    yBottom = -GetScrollPos(hwnd, SB_VERT);     // offset for scrollbar

    // If we currently have a stream name selected, we must
    // deselect it.
    if (gSelectedStream >= MAXNUMSTREAMS) {
    // Erase the select marks
    if (ghwndEdit)
        EditDone(hwnd, FALSE);
    else
        InvalidateRect(hwnd, &grcSelectedStream, TRUE);

    // Stream no longer selected.
    gSelectedStream = -1;
    }
    else {
    //
    // Otherwise, if the shift key isn't down,
    // we deselect everything first
    //
    fShift = GetAsyncKeyState(VK_SHIFT) & 0x8000;
    fCtrl = GetAsyncKeyState(VK_CONTROL) & 0x8000;
    if (!fShift) {
        // Invalidate any stream that has something selected.  It needs
        // to redraw now.
        for (j = 0; j < gcpavi; j++) {
        if (galSelStart[j] != -1) {
            rc.top = gStreamTop[j] - GetScrollPos(hwnd, SB_VERT);
            rc.bottom =gStreamTop[j+1] -GetScrollPos(hwnd, SB_VERT);
            InvalidateRect(hwnd, &rc, TRUE); // needs to erase
        }
        }
        // Deselect everything
        SelectStream(hwnd, -1, -1, -1, FALSE, FALSE);
    }
    }


    //
    // Walk the streams and find out where we clicked
    //
    for (i=0; i<gcpavi; i++) {
    AVIStreamInfo(gapavi[i], &avis, sizeof(avis));

    // See if they clicked on the name
    yTop = gStreamTop[i] - GetScrollPos(hwnd, SB_VERT);
    yBottom = yTop + (2 * TSPACE);  // !!! size of stream header

    if (y >= yTop && y < yBottom) {

        gSelectedStream = MAXNUMSTREAMS+i;  // which stream's header it is
        rc.top = yTop;
        rc.bottom = yBottom;
        grcSelectedStream = rc;     // Invalidate this on button up

        InvalidateRect(hwnd, &rc, FALSE);   // repaint whole strip

        // No need to be here anymore
        return;
    }


    //*******************************************************************
    // See if they clicked on the information Header
    yTop = yBottom;
    yBottom = yTop + (2 * TSPACE);  // !!! size of stream header

    //
    // If they've clicked on the header - select the whole stream
    //
    if (y >= yTop && y < yBottom) {

        // Maybe select everything if Ctrl is held down
        SelectStream(hwnd, i, AVIStreamStart(gapavi[i]),
             AVIStreamEnd(gapavi[i]), FALSE, fCtrl);

        // Tell paint code to highlight the text area.  Invalidate
        // the whole stream area.  When they let go of the mouse,
        // redraw the text area only.
        gSelectedStream = i;        // which stream's header it is
        rc.top = yTop;
        rc.bottom = yBottom;
        grcSelectedStream = rc;     // Invalidate this on button up
        // Now get the area of the whole stream
        rc.bottom = gStreamTop[i + 1] - GetScrollPos(hwnd, SB_VERT);
        InvalidateRect(hwnd, &rc, FALSE);   // repaint whole strip

        // Time to go
        return;
    }

    // *******************************************************************

    //
    // Now get the area of the stream data, and...
    //
    yTop = yBottom;
    yBottom = gStreamTop[i + 1] - GetScrollPos(hwnd, SB_VERT);

    //
    // ... see if we clicked on a video frame, or...
    //
    if (avis.fccType == streamtypeVIDEO) {
        if (gapgf[i] == NULL)
        continue;

        //
        // We're in the vertical range of the strip of video
        //
        if (y >= yTop && y < yBottom) {

        rc.top = yTop; rc.bottom = yBottom;
        // Time at the centre of the strip
        lTime = GetScrollTime(hwnd);
        // What frame should appear in the centre? Times that
        // are too big will all return the last frame, so we
        // need to calculate the hypothetical frame number
        if (lTime <= AVIStreamEndTime(gapavi[i])) {
            lSamp = AVIStreamTimeToSample(gapavi[i], lTime);
        }
        else {
            lSamp = AVIStreamEnd(gapavi[i]) +
                AVIStreamTimeToSample(gapavi[i],
                          lTime - AVIStreamEndTime(gapavi[i]));
        }
        // How wide is each frame?
        iFrameWidth = (avis.rcFrame.right - avis.rcFrame.left) *
                  gwZoom / 4 + HSPACE;    // !!! hacky constant
        // How many frames on each half of centre?
        nFrames = (rcC.right - iFrameWidth) / (2 * iFrameWidth);
        if (nFrames < 0)
            nFrames = 0;        // at least show *something*

        //
        // Walk all frames and find which one we're on top of
        //
        for (n = -nFrames; n <= nFrames; n++) {

            rc.left   = rcC.right / 2 -
                (avis.rcFrame.right * gwZoom / 4) / 2 +
                (n * iFrameWidth);
            rc.right = rc.left + iFrameWidth;

            //
            // We're on top of this frame!
            //
            if (x >= rc.left && x < rc.right) {
            //
            // For the top video stream, it's easy to tell
            // which frame we're on... each frame is
            // displayed in order.
            //
            if (i == giFirstVideo)
                SelectStream(hwnd, i, lSamp + n, 1, fShift, fCtrl);


            //
            // For other video streams, we need to calculate
            // the time of the spot we're on, and see which
            // frame is associated with it, because who
            // knows what scale we're using for time.
            //
            else {
                l = lTime + MulDiv32(n * iFrameWidth, gdwMicroSecPerPixel, 1000);
                lCurSamp = AVIStreamTimeToSample( gapavi[i], l);
                SelectStream(hwnd, i, lCurSamp, 1, fShift, fCtrl);
            }

            //
            // Invalidate what we'll be highlighting.
            // This includes the text area above.  If
            // we're adding to a selection, invalidate the
            // whole strip because other frames might
            // become selected by this, and the text
            // changes.
            //
            InflateRect(&rc, HSPACE / 2, VSPACE / 2);
            if (fShift) {       // could select more than this
                rc.left = 0;
                rc.right = rcC.right;
            }
            InvalidateRect(hwnd, &rc, FALSE);
            // Now invalidate the text area
            rc.bottom = rc.top;
            rc.top -= (2 * TSPACE); // !!! text changes
            rc.left = 0;
            rc.right = rcC.right;
            // If we've got selection text already, erase
            InvalidateRect(hwnd, &rc, fShift);
            return;
            }
        }//end of inner frame walk for statement
        }
    }

    // ********************************************************************

    //
    // ... see if we clicked on an audio section
    //
    else if (avis.fccType == streamtypeAUDIO) {

        //
        // We clicked inside the wave!
        //
        if (y >= yTop && y < yBottom) {

        //
        // Get the time we clicked on, and it's sample number
        //
        GetClientRect(hwnd, &rcC);
        lTime = GetScrollTime(hwnd);
        if (x < (rcC.right/2)) { //button down to the left of current position
            l = lTime - muldiv32( (rcC.right / 2) - x, gdwMicroSecPerPixel, 1000);
        }
        else {
            l = lTime + muldiv32(x - rcC.right / 2, gdwMicroSecPerPixel, 1000);
        }
        lCurSamp = AVIStreamTimeToSample(gapavi[i], l);

        SelectStream(hwnd, i, lCurSamp, 1, fShift, fCtrl);

        // Invalidate what we'll need to repaint to show it
        rc.left = x - 2;        // may not be exact right pixel
        rc.right = x + 3;
        rc.top = yTop;
        rc.bottom = yBottom;
        InflateRect(&rc, 0, VSPACE / 2);
        // If we're adding to a selection, we better invalidate
        // the whole strip.
        if (fShift) {
            rc.left = 0;
            rc.right = rcC.right;
        }
        InvalidateRect(hwnd, &rc, FALSE);
        // Now invalidate the header text
        rc.bottom = rc.top;
        rc.top -= (2 * TSPACE); // !!! text changes
        rc.left = 0;
        rc.right = rcC.right;
        // If we've got selection text already, erase
        InvalidateRect(hwnd, &rc, fShift);
        }
    }
    }//end of stream walk for statement


    return;
}
// ****************************************************************************
//
//      Message Handler for WM_LBUTTONUP
//
// ****************************************************************************
//
void App_OnLButtonUp(HWND hwnd, int x, int y, UINT keyFlags)
{
    //
    // If we're selecting a whole stream, stop highlighting the text area
    //
    if ((gSelectedStream >= 0) && (gSelectedStream < MAXNUMSTREAMS))
    {
    InvalidateRect(hwnd, &grcSelectedStream, TRUE);
    gSelectedStream = -1;
    }
    return;
}
/*----------------------------------------------------------------------------*\
|   AppWndProc( hwnd, uiMessage, wParam, lParam )                              |
|                                                                              |
|   Description:                                                               |
|       The window proc for the app's main (tiled) window.  This processes all |
|       of the parent window's messages.                                       |
|                                                                              |
|   Arguments:                                                                 |
|       hwnd            window handle for the window                           |
|       uiMessage       message number                                         |
|       wParam          message-dependent                                      |
|       lParam          message-dependent                                      |
|                                                                              |
|   Returns:                                                                   |
|       0 if processed, nonzero if ignored                                     |
|                                                                              |
\*----------------------------------------------------------------------------*/
LRESULT CALLBACK AppWndProc( HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
    PAINTSTRUCT ps;
    BOOL        f;
    HDC         hdc;

    switch (msg) {

    //
    // If we passed a command line filename, open it
    //
    case WM_CREATE:
        return HANDLE_WM_CREATE(hwnd, wParam, lParam, App_OnCreate);

    case WM_COMMAND:
        HANDLE_WM_COMMAND(hwnd, wParam, lParam, App_OnCommand);
        break;

    case WM_DROPFILES:
        HANDLE_WM_DROPFILES(hwnd, wParam, lParam, App_OnDropFiles);
        break;

    case WM_INITMENU:
        HANDLE_WM_INITMENU(hwnd, wParam, lParam, App_OnInitMenu);
        break;

        //
        // During a wait state (eg saving) don't let us choose any menus
        //
    case WM_NCHITTEST:

        if (gfWait)
        {
        // Let windows tell us where the cursor is
        lParam = DefWindowProc(hwnd,msg,wParam,lParam);

        // If it's over a menu, pretend it's in the client (force
        // hourglass)
        if (lParam == HTMENU)
            lParam = HTCLIENT;

        return lParam;
        }
        break;
        //
        // Set vertical scrollbar for scrolling streams
        //
    case WM_SIZE:
        HANDLE_WM_SIZE(hwnd, wParam, lParam, App_OnSize);
        break;

        //
        // During a wait state, show an hourglass over our client area
        // !!! Is this necessary?
        //
    case WM_SETCURSOR:
        if (gfWait && LOWORD(lParam) == HTCLIENT)
        {
        SetCursor(LoadCursor(NULL, IDC_WAIT));
        return TRUE;
        }
        break;

        //
        // We're out of here!
        //
    case WM_DESTROY:
        HANDLE_WM_DESTROY(hwnd, wParam, lParam, App_OnDestroy);\
            break;

    case WM_ENDSESSION:
        HANDLE_WM_ENDSESSION(hwnd, wParam, lParam, App_OnEndSession);
        break;

        //
        // Don't let us close ourselves in a wait state (eg saving)
        //
    case WM_CLOSE:
        if (gfWait)
        return 0;
        break;

        //
        // Block keyboard access to menus if waiting
        //
    case WM_SYSCOMMAND:
        switch (wParam & 0xFFF0) {
        case SC_KEYMENU:
            if (gfWait)
            return 0;
            break;
        }
        break;

    case WM_PALETTECHANGED:
        HANDLE_WM_PALETTECHANGED(hwnd, wParam, lParam, App_OnPaletteChanged);
        break;

    case WM_QUERYNEWPALETTE:

        if (gfVideoFound) {
        hdc = GetDC(hwnd);
        //
        // Realize the palette of the first video stream
        //
        if (f = DrawDibRealize(ghdd[giFirstVideo], hdc, FALSE))
            InvalidateRect(hwnd,NULL,TRUE);

        ReleaseDC(hwnd,hdc);
        return f;
        }
        break;

    case WM_ERASEBKGND:
        break;

    case WM_PAINT:
        hdc = BeginPaint(hwnd,&ps);

        PaintStuff(hdc, hwnd, FALSE);

        EndPaint(hwnd,&ps);
        break;

    //
    // handle the keyboard interface
    //
    case WM_KEYDOWN:
        HANDLE_WM_KEYDOWN(hwnd, wParam, lParam, App_OnKey);
        break;

    case WM_HSCROLL:
        HANDLE_WM_HSCROLL(hwnd, wParam, lParam, App_OnHScroll);
        break;

    case WM_VSCROLL:
        HANDLE_WM_VSCROLL(hwnd, wParam, lParam, App_OnVScroll);
        break;

    //
    // Deselect everything
    //
    case WM_RBUTTONDOWN:
        HANDLE_WM_RBUTTONDOWN(hwnd, wParam, lParam, App_OnRButtonDown);
        break;

    //
    // Select something
    //
    case WM_LBUTTONDOWN:
        HANDLE_WM_LBUTTONDOWN(hwnd, wParam, lParam, App_OnLButtonDown);
        break;

    case WM_LBUTTONDBLCLK:
        HANDLE_WM_LBUTTONDBLCLK(hwnd, wParam, lParam, App_OnLButtonDown);
        break;

    case WM_LBUTTONUP:
        HANDLE_WM_LBUTTONUP(hwnd, wParam, lParam, App_OnLButtonUp);
        break;

    //
    // Wave driver wants to tell us something.  Pass it on.
    //
    case MM_WOM_OPEN:
    case MM_WOM_DONE:
    case MM_WOM_CLOSE:
        aviaudioMessage(hwnd, msg, wParam, lParam);
        break;
    }
    return DefWindowProc(hwnd,msg,wParam,lParam);
}

/*----------------------------------------------------------------------------*\
|    SaveCallback()                                                             |
|                                                                               |
|    Our save callback that prints our progress in our window title bar         |
\*----------------------------------------------------------------------------*/
BOOL CALLBACK SaveCallback(int iProgress)
{
    char    szText[3*BUFSIZE];
    char    szFormat[BUFSIZE];

    LoadString( ghInstApp, IDS_APPNAME, gszBuffer, BUFSIZE );
    LoadString( ghInstApp, IDS_SAVEFORMAT, szFormat, BUFSIZE );

    wsprintf(szText, szFormat, (LPSTR) gszBuffer, (LPSTR) gszSaveFileName, iProgress);

    SetWindowText(ghwndApp, szText);

    //
    // Give ourselves a chance to abort
    //
    return WinYield();
}


/*----------------------------------------------------------------------------*\
|    GetDlgItemLong()                                                           |
|                                                                               |
|    Get a long integer from a dialog item.                                     |
\*----------------------------------------------------------------------------*/

DWORD GetDlgItemLong (HWND hwnd,  int idCtl, LPINT lpfOK, BOOL fSigned)
{
    LONG        l;
    char        ch;
    BOOL        fNegative = FALSE;
    char        szBuf[64];
    LPSTR       pbuf = szBuf;
    BOOL        fOk;


    fOk = FALSE;
    if (lpfOK)
    *lpfOK = FALSE;

    if (!GetDlgItemText(hwnd, idCtl, (LPSTR)szBuf, sizeof(szBuf)-1))
    return(0);

    while (*pbuf == ' ') pbuf++;

    if (fSigned && *pbuf == '-')
    {
    pbuf++;
    fNegative = TRUE;
    }

    l = 0;
    while ((ch = *pbuf++) >= '0' && ch <= '9')
    {
    fOk = TRUE;
    if (l > (DWORD)(ULONG_MAX/10))
        return(0);
    l = (l * 10) + ch - '0';
    if (fSigned && l > (DWORD)(ULONG_MAX/2))
        return(0);
    }

    if (fNegative)
    l = -l;

    if (lpfOK)
    *lpfOK = (ch == 0 && fOk);

    return(l);
}

/*----------------------------------------------------------------------------*\
|    SetDlgItemLong()                                                           |
|                                                                               |
|    Put a long integer into a dialog item.                                     |
\*----------------------------------------------------------------------------*/

void SetDlgItemLong (HWND hwnd, int idCtl, DWORD dwValue, BOOL fSigned )
{
    char szBuf[64];

    wsprintf (szBuf, fSigned ? "%ld" : "%lu", dwValue);
    SetDlgItemText(hwnd, idCtl, szBuf);
}


/*----------------------------------------------------------------------------*\
|    DoDataExchange()                                                           |
|                                                                               |
|    Exchange data between our internal buffer and dialog controls              |
|    fDir = TRUE for DialogBox->Buffer                                          |
|         = FALSE for Buffer->DialogBox                                         |
\*----------------------------------------------------------------------------*/

void DoDataExchange (HWND hwnd, LPAVISTREAMINFO lpinfo, BOOL fDir)
{
    if (fDir) {
    lpinfo->wPriority       = (WORD)GetDlgItemInt (hwnd, IDC_PRIORITY,    NULL, FALSE);
    lpinfo->wLanguage       = (WORD)GetDlgItemInt (hwnd, IDC_LANGUAGE,    NULL, FALSE);
    lpinfo->dwScale         = GetDlgItemLong(hwnd, IDC_SCALE,       NULL, FALSE);
    lpinfo->dwRate          = GetDlgItemLong(hwnd, IDC_RATE,        NULL, FALSE);
    lpinfo->dwStart         = GetDlgItemLong(hwnd, IDC_START,       NULL, FALSE);
    lpinfo->dwQuality       = GetDlgItemLong(hwnd, IDC_QUALITY,     NULL, FALSE);
    lpinfo->rcFrame.top     = GetDlgItemInt (hwnd, IDC_FRAMETOP,    NULL, TRUE);
    lpinfo->rcFrame.bottom  = GetDlgItemInt (hwnd, IDC_FRAMEBOTTOM, NULL, TRUE);
    lpinfo->rcFrame.left    = GetDlgItemInt (hwnd, IDC_FRAMELEFT,   NULL, TRUE);
    lpinfo->rcFrame.right   = GetDlgItemInt (hwnd, IDC_FRAMERIGHT,  NULL, TRUE);
    GetDlgItemText(hwnd, IDC_NAME, lpinfo->szName, sizeof(lpinfo->szName)-1);
    }
    else
    {
    SetDlgItemInt (hwnd, IDC_PRIORITY,    lpinfo->wPriority,       FALSE);
    SetDlgItemInt (hwnd, IDC_LANGUAGE,    lpinfo->wLanguage,       FALSE);
    SetDlgItemLong(hwnd, IDC_SCALE,       lpinfo->dwScale,         FALSE);
    SetDlgItemLong(hwnd, IDC_RATE,        lpinfo->dwRate,          FALSE);
    SetDlgItemLong(hwnd, IDC_START,       lpinfo->dwStart,         FALSE);
    SetDlgItemLong(hwnd, IDC_QUALITY,     lpinfo->dwQuality,       FALSE);
    SetDlgItemLong(hwnd, IDC_FRAMETOP,    lpinfo->rcFrame.top,     TRUE);
    SetDlgItemLong(hwnd, IDC_FRAMEBOTTOM, lpinfo->rcFrame.bottom,  TRUE);
    SetDlgItemLong(hwnd, IDC_FRAMELEFT,   lpinfo->rcFrame.left,    TRUE);
    SetDlgItemLong(hwnd, IDC_FRAMERIGHT,  lpinfo->rcFrame.right,   TRUE);
    SetDlgItemText(hwnd, IDC_NAME, lpinfo->szName);
    }
}

// *****************************************************************************
//
//      FUNCTION: Dlg_DefProc(HWND, UINT, WPARAM, LPARAM)
//
//      PURPOSE:  Handles default messages for all dialog boxes
//
//
static LRESULT Dlg_DefProc( HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam )
{
    return DefDlgProcEx( hDlg, message, wParam, lParam, &gfDefDlgEx );
}
//
// *****************************************************************************
//
//      FUNCTION: InfoDlg_OnInitDialog(HWND, HWND, LPARAM)
//
//      PURPOSE:  Handles initialization for dialog box
//
//
static BOOL InfoDlg_OnInitDialog(HWND hDlg, HWND hwndFocus, LPARAM lParam)
{
    int i;
    glpavisi = (LPAVISTREAMINFO)
           GlobalAllocPtr (GHND, sizeof(AVISTREAMINFO)*gcpavi);

    for ( i = 0; i < gcpavi; ++i)
    {
    AVIStreamInfo(gapavi[i], &glpavisi[i], sizeof(AVISTREAMINFO));
    SendDlgItemMessage(hDlg, IDC_STREAMS, CB_ADDSTRING, 0, (LPARAM)(LPSTR)glpavisi[i].szName);
    }
    SendDlgItemMessage(hDlg, IDC_STREAMS, CB_SETCURSEL, 0, 0);
    gnSel = 0;
    DoDataExchange(hDlg, &glpavisi[0], FALSE);

    return (FALSE);
}
//
// *****************************************************************************
//
//      FUNCTION: InfoDlg_OnCommand(HWND, HWND, UINT)
//
//      PURPOSE:  Handles the child controls for dialog box
//
//      DIALOGBOX ID'S
//
//              IDOK            - ok button
//              IDCANCEL        - cancel button
//      IDC_STREAMS             - the dropdown listbox
//
static void InfoDlg_OnCommand(HWND hDlg, int control_source, HWND control_handle, UINT control_action )
{

    switch (control_source)
    {
    case IDC_STREAMS:
    {
        if (control_action != CBN_SELCHANGE)
        break;
        if (gnSel != CB_ERR)
        DoDataExchange (hDlg, &glpavisi[gnSel], TRUE);
        gnSel = (int)SendDlgItemMessage(hDlg, IDC_STREAMS, CB_GETCURSEL, 0, 0);
        if (gnSel != CB_ERR)
        DoDataExchange(hDlg, &glpavisi[gnSel], FALSE);
    }
    break;

    case IDOK:
    case IDCANCEL:
    {
        BOOL fOk = (control_source == IDOK);
        int i,ix;

        if (fOk)
        {
        ix = (int)SendDlgItemMessage(hDlg, IDC_STREAMS, CB_GETCURSEL, 0, 0);
        if (ix != CB_ERR)
            DoDataExchange(hDlg, &glpavisi[ix], TRUE);

        for (i = 0; i < gcpavi; ++i)
            EditStreamSetInfo(gapavi[i], &glpavisi[i], sizeof(AVISTREAMINFO));
        }
        GlobalFreePtr(glpavisi);
        EndDialog(hDlg, fOk);
    }
    break;

    }
    return;
}
//
// *****************************************************************************
//
//      FUNCTION: SetInfoNewDlgProc(HWND, UINT, WPARAM, LPARAM)
//
//      PURPOSE:  Processes messages for dialog box using message crackers
//
//      MESSAGES:
//
//              WM_INITDIALOG   - initialize dialog box
//              WM_COMMAND              - process user input
//
// *****************************************************************************
//
static LRESULT SetInfoNewDlgProc( HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
    switch (message)
    {
    HANDLE_MSG( hDlg, WM_INITDIALOG,            InfoDlg_OnInitDialog            );
    HANDLE_MSG( hDlg, WM_COMMAND,                       InfoDlg_OnCommand               );
    default:
        return Dlg_DefProc( hDlg, message, wParam, lParam );
    }
}
//
//
// *****************************************************************************
//
//      FUNCTION: SetInfoDlgProc(HWND, UINT, WPARAM, LPARAM)
//
//      PURPOSE:  Processes messages for info dialog box
//
//
BOOL CALLBACK SetInfoDlgProc( HWND hDlg, UINT message, WPARAM wParam, LPARAM lParam)
{
    CheckDefDlgRecursion( &gfDefDlgEx );
    return SetDlgMsgResult( hDlg, message, SetInfoNewDlgProc( hDlg, message, wParam, lParam ) );
}


/*----------------------------------------------------------------------------*\
|    SetStreamInfo()                                                            |
|                                                                               |
|    Bring up the dialog to allow setting the stream info                       |
\*----------------------------------------------------------------------------*/

BOOL SetStreamInfo (HWND hwnd)
{
    return(DialogBox(ghInstApp, MAKEINTRESOURCE(IDD_STREAMINFO), hwnd, (DLGPROC)SetInfoDlgProc));
}



/*----------------------------------------------------------------------------*\
|    editPaste()                                                                |
|                                                                               |
|    PASTE the streams in this PFILE into our movie using the following logic:  |
|                                                                               |
|    Take a stream from the clipboard.  If you can find a similar type stream   |
|    in the app with a selection, paste it in before the selection.  If no      |
|    such stream exists, add it to the end.                                     |
\*----------------------------------------------------------------------------*/

void editPaste(HWND hwnd, PAVIFILE pfile)
{
    int         i, j, nVideo = 0, nAudio = 0, nStream;
    LONG        l;
    PAVISTREAM  pavi;
    AVISTREAMINFO avisClip, avis;

    FreeDrawStuff(hwnd);

    for (i=0; i<MAXNUMSTREAMS; i++) {
    if (AVIFileGetStream(pfile, &pavi, 0L, i) != AVIERR_OK)
        break;
    AVIStreamInfo(pavi, &avisClip, sizeof(avisClip));
    nStream = (avisClip.fccType == streamtypeVIDEO) ? nVideo : nAudio;
    for (j=nStream; j<gcpavi; j++) {
        AVIStreamInfo(gapavi[j], &avis, sizeof(avis));
        if (avis.fccType == avisClip.fccType && galSelStart[j] != -1) {
        l = AVIStreamLength(pavi);
        if (EditStreamPaste(gapavi[j], &galSelStart[j], &l,
                    pavi, AVIStreamStart(pavi), AVIStreamLength(pavi)) !=
            AVIERR_OK)
        {
            LoadString( ghInstApp, IDS_NOPASTE, gszBuffer, BUFSIZE );
            ErrMsg(gszBuffer);
        }
        galSelLen[j] = AVIStreamLength(pavi);
        break;
        }
    }
    if (j == gcpavi) {
        galSelStart[j] = AVIStreamStart(pavi);
        galSelLen[j] = AVIStreamLength(pavi);
        if (CreateEditableStream(&gapavi[j], pavi) != AVIERR_OK)
        {
        LoadString( ghInstApp, IDS_PASTEERROR, gszBuffer, BUFSIZE );
        ErrMsg(gszBuffer);
        AVIStreamRelease(pavi);
        break;
        }
        AVIStreamRelease(pavi);
        gcpavi++;
    }
    if (avisClip.fccType == streamtypeVIDEO)
        nVideo = ++j;
    else
        nAudio = ++j;
    }
    AVIFileRelease(pfile);
    InitStreams(hwnd);
    FixWindowTitle(hwnd);
}
/*----------------------------------------------------------------------------*\
|    MenuHandler()                                                              |
|                                                                               |
|    Process all of our Menu messages.                                  |
\*----------------------------------------------------------------------------*/
BOOL MenuHandler( HWND hwnd, int nMenuID )
{
    OPENFILENAME ofn;

    switch(nMenuID)
    {
    case MENU_ABOUT:
        //
        // Display an informative dialog box.
        //
        DialogBox(ghInstApp, MAKEINTRESOURCE(IDD_ABOUT), hwnd, (DLGPROC)AboutDlgProc);
        break;
        //
        // We want out of here!
        //
    case MENU_EXIT:
        PostMessage(hwnd,WM_CLOSE,0,0L);
        break;

        //
        // Set the compression options for each stream - pass an array of
        // streams and an array of compression options structures
        //
    case MENU_OPTIONS:
        AVISaveOptions(hwnd,
               ICMF_CHOOSE_KEYFRAME | ICMF_CHOOSE_DATARATE |
               ICMF_CHOOSE_PREVIEW,
               gcpavi, gapavi, galpAVIOptions);
        break;

        //
        // Save all the open streams into a file
        //
    case MENU_SAVEAS:

        gszSaveFileName[0] = 0;

        //
        // prompt user for file to save
        //
        ofn.lStructSize = sizeof(OPENFILENAME);
        ofn.hwndOwner = hwnd;
        ofn.hInstance = NULL;
        AVIBuildFilter(gszFilter, sizeof(gszFilter), TRUE);
        ofn.lpstrFilter = gszFilter;
        ofn.lpstrCustomFilter = NULL;
        ofn.nMaxCustFilter = 0;
        ofn.nFilterIndex = 0;
        ofn.lpstrFile = gszSaveFileName;
        ofn.nMaxFile = sizeof(gszSaveFileName);
        ofn.lpstrFileTitle = NULL;
        ofn.nMaxFileTitle = 0;
        ofn.lpstrInitialDir = NULL;
        LoadString( ghInstApp, IDS_SAVETITLE, gszBuffer, BUFSIZE );
        ofn.lpstrTitle = gszBuffer;
        ofn.Flags = OFN_PATHMUSTEXIST | OFN_HIDEREADONLY |
            OFN_OVERWRITEPROMPT;
        ofn.nFileOffset = 0;
        ofn.nFileExtension = 0;
        LoadString( ghInstApp, IDS_DEFEXT, gszBuffer, BUFSIZE );
        ofn.lpstrDefExt = gszBuffer;
        ofn.lCustData = 0;
        ofn.lpfnHook = NULL;
        ofn.lpTemplateName = NULL;

        //
        // If we get a filename, save it
        //
        if (GetSaveFileName(&ofn))
        {
            DWORD       fccHandler[MAXNUMSTREAMS];
            int         i;
            HRESULT     hr;

            StartWait();

            for (i = 0; i < gcpavi; i++)
            fccHandler[i] = galpAVIOptions[i]->fccHandler;

            hr = AVISaveV(gszSaveFileName,
                  NULL,
                  (AVISAVECALLBACK) SaveCallback,
                  gcpavi,
                  gapavi,
                  galpAVIOptions);
        if (hr != AVIERR_OK) {
            switch (hr) {
            case AVIERR_FILEOPEN:
            LoadString( ghInstApp, IDS_ERROVERWRITE, gszBuffer, BUFSIZE );
            ErrMsg(gszBuffer);
            break;
            default:
            LoadString( ghInstApp, IDS_SAVEERROR, gszBuffer, BUFSIZE );
            ErrMsg(gszBuffer);
            }
        }
            // Now put the video compressors back that we stole
            for (i = 0; i < gcpavi; i++)
            galpAVIOptions[i]->fccHandler = fccHandler[i];

            EndWait();
            FixWindowTitle(hwnd);
        }
        break;

        //
        // Close everything
        //
    case MENU_CLOSE:
        FreeAvi(hwnd);
        gszFileName[0] = '\0';
        FixWindowTitle(hwnd);
        break;

        //
        // Open a new file, or merge streams with a new file
        //
    case MENU_OPEN:
    case MENU_MERGE:
        gszFileName[0] = 0;

        //
        // prompt user for file to open
        //
        ofn.lStructSize = sizeof(OPENFILENAME);
        ofn.hwndOwner = hwnd;
        ofn.hInstance = NULL;
        if (nMenuID == MENU_MERGE)
        LoadString( ghInstApp, IDS_MERGETITLE, gszBuffer, BUFSIZE );
        else
        LoadString( ghInstApp, IDS_OPENTITLE, gszBuffer, BUFSIZE );
        ofn.lpstrTitle = gszBuffer;
        AVIBuildFilter(gszFilter, sizeof(gszFilter), FALSE);
        ofn.lpstrFilter = gszFilter;
        ofn.lpstrCustomFilter = NULL;
        ofn.nMaxCustFilter = 0;
        ofn.nFilterIndex = 0;
        ofn.lpstrFile = gszFileName;
        ofn.nMaxFile = sizeof(gszFileName);
        ofn.lpstrFileTitle = NULL;
        ofn.nMaxFileTitle = 0;
        ofn.lpstrInitialDir = NULL;
        ofn.Flags = OFN_FILEMUSTEXIST | OFN_PATHMUSTEXIST |OFN_HIDEREADONLY;
        ofn.nFileOffset = 0;
        ofn.nFileExtension = 0;
        ofn.lpstrDefExt = NULL;
        ofn.lCustData = 0;
        ofn.lpfnHook = NULL;
        ofn.lpTemplateName = NULL;

        //
        // If we've got a filename, go open it
        //
        if (GetOpenFileNamePreview(&ofn))
        InitAvi(hwnd, gszFileName, nMenuID);

        break;

    case MENU_ZOOMQUARTER:
        gwZoom = 1;
        FixScrollbars(hwnd);
        InvalidateRect(hwnd, NULL, TRUE);
        break;

    case MENU_ZOOMHALF:
        gwZoom = 2;
        FixScrollbars(hwnd);
        InvalidateRect(hwnd, NULL, TRUE);
        break;

    case MENU_ZOOM1:
        gwZoom = 4;
        FixScrollbars(hwnd);
        InvalidateRect(hwnd, NULL, TRUE);
        break;

    case MENU_ZOOM2:
        gwZoom = 8;
        FixScrollbars(hwnd);
        InvalidateRect(hwnd, NULL, TRUE);
        break;

    case MENU_ZOOM4:
        gwZoom = 16;
        FixScrollbars(hwnd);
        InvalidateRect(hwnd, NULL, TRUE);
        break;

    //
    // Simulate playing the file.  We just play the 1st audio stream and let
    // our main message loop scroll the video by whenever it's bored.
    //
    case MENU_PREVIEW:
        if (gfAudioFound)
        aviaudioPlay(hwnd,
                 gapavi[giFirstAudio],
                 AVIStreamTimeToSample(gapavi[giFirstAudio], GetScrollTime(hwnd)),
                 AVIStreamEnd(gapavi[giFirstAudio]),
                 FALSE);
        gfPlaying = TRUE;
        glPlayStartTime = timeGetTime();
        glPlayStartPos = GetScrollTime(hwnd);
        break;

        //
        // Stop the play preview
        //
    case MENU_STOP:
        if (gfAudioFound)
        aviaudioStop();
        gfPlaying = FALSE;
        break;

    case MENU_SETINFO:
        if (SetStreamInfo(hwnd))
        {
        FreeDrawStuff(hwnd);        // !!! in order to call InitStreams
        InitStreams(hwnd);          // !!! Nukes COMP options
        InvalidateRect(hwnd, NULL, TRUE);
        }
        break;

    case MENU_CUT:
    case MENU_COPY:
    case MENU_DELETE:
    {
        PAVIFILE    pf;
        int         i;

        //
        // Walk our list of selections and make streams out of each section
        //
        gcpaviSel = 0;
        for (i = 0; i < gcpavi; i++) {
        if (galSelStart[i] != -1) {
            // !!! What if the start and length change?
            if (nMenuID == MENU_COPY) {
            if (EditStreamCopy(gapavi[i], &galSelStart[i],
                       &galSelLen[i], &gapaviSel[gcpaviSel++]) != 0) {
                --gcpaviSel;
                LoadString( ghInstApp, IDS_STRCPYERR, gszBuffer, BUFSIZE );
                ErrMsg(gszBuffer);
            }
            } else {
            if (EditStreamCut(gapavi[i], &galSelStart[i],
                      &galSelLen[i], &gapaviSel[gcpaviSel++]) != 0) {
                --gcpaviSel;
                LoadString( ghInstApp, IDS_STRCUTERR, gszBuffer, BUFSIZE );
                ErrMsg(gszBuffer);
            }
            }
        }
        }


        for (i = gcpavi - 1; i >= 0; i--) {
        // Check to see if any stream is entirely gone now....
        if (AVIStreamLength(gapavi[i]) == 0) {
            NukeAVIStream(i);
        }
        }

        //
        // Put the selected stuff up on the clipboard
        //
        if (gcpaviSel && nMenuID != MENU_DELETE) {
        PAVISTREAM          gapaviTemp[MAXNUMSTREAMS];
        int i;

        //
        // Clone the edited streams, so that if the user does
        // more editing, the thing on the clipboard won't
        // suddenly change....
        //
        for (i = 0; i < gcpaviSel; i++) {
            gapaviTemp[i] = NULL;
            // !!! error check
            EditStreamClone(gapaviSel[i], &gapaviTemp[i]);
        }

        AVIMakeFileFromStreams(&pf, gcpaviSel, gapaviTemp);
        if (AVIPutFileOnClipboard(pf) != AVIERR_OK)
        {
            LoadString( ghInstApp, IDS_NOCLIP, gszBuffer, BUFSIZE );
            ErrMsg(gszBuffer);
        }
        for (i = 0; i < gcpaviSel; i++) {
            AVIStreamRelease(gapaviTemp[i]);
        }

        AVIFileRelease(pf);
        }

        for (i = 0; i < gcpaviSel; i++)
        AVIStreamRelease(gapaviSel[i]);

        //
        // If we cut out the selections, then they don't exist anymore.
        //
        if (gcpaviSel && (nMenuID == MENU_DELETE || nMenuID == MENU_CUT)) {
        SelectStream(hwnd, -1, -1, -1, FALSE, FALSE);
        }

        //
        // We just changed the world!
        //
        FreeDrawStuff(hwnd);        // !!! in order to call InitStreams
        InitStreams(hwnd);          // !!! Nukes COMP options
        InvalidateRect(hwnd, NULL, TRUE);

        break;
    }

    case MENU_PASTE:
    {
        PAVIFILE pf;

        AVIGetFromClipboard(&pf);

        if (pf) {
        editPaste(hwnd, pf);
        }
        break;
    }
    case MENU_NAME:
        if (ghwndEdit == NULL)
        EditStreamName(hwnd);
        else
        EditDone(hwnd, FALSE);


        break;
    }
    return TRUE;
}
/*-----------------------------------------------------------------------------
 * FrameVideo()
 *
 * Puts a border around a video frame, the size of a selection
 */

void FrameVideo(HDC hdc, RECT *rcFrame, HBRUSH hbr)
{
   RECT rcTop,rcBottom,rcLeft,rcRight;
   HBRUSH hbrOld;

   // Calculate 4 rectangles, which 'frame' rcFrame.
   rcTop.left = rcFrame->left - HSPACE/2;
   rcTop.top = rcFrame->top - SELECTVSPACE;
   rcTop.right = rcFrame->right + HSPACE/2;
   rcTop.bottom = rcFrame->top;
   rcLeft.left = rcFrame->left - HSPACE/2;
   rcLeft.top = rcFrame->top - SELECTVSPACE;
   rcLeft.right = rcFrame->left;
   rcLeft.bottom = rcFrame->bottom + SELECTVSPACE;
   rcRight.left = rcFrame->right;
   rcRight.top = rcFrame->top - SELECTVSPACE;
   rcRight.right = rcFrame->right + HSPACE/2;
   rcRight.bottom = rcFrame->bottom + SELECTVSPACE;
   rcBottom.left = rcFrame->left - HSPACE/2;
   rcBottom.top = rcFrame->bottom;
   rcBottom.right = rcFrame->right + HSPACE/2;
   rcBottom.bottom = rcFrame->bottom + SELECTVSPACE;

   // Now put each rectangle on screen
   hbrOld = SelectObject(hdc, hbr);
   PatBlt(hdc, rcTop.left, rcTop.top, rcTop.right - rcTop.left, rcTop.bottom - rcTop.top, PATCOPY);
   PatBlt(hdc, rcLeft.left, rcLeft.top, rcLeft.right - rcLeft.left, rcLeft.bottom - rcLeft.top, PATCOPY);
   PatBlt(hdc, rcRight.left, rcRight.top, rcRight.right - rcRight.left, rcRight.bottom - rcRight.top, PATCOPY);
   PatBlt(hdc, rcBottom.left, rcBottom.top, rcBottom.right - rcBottom.left, rcBottom.bottom - rcBottom.top, PATCOPY);
   SelectObject(hdc, hbrOld);

}

/*----------------------------------------------------------------------------*\
|   ErrMsg()                                                                    |
|                                                                               |
|   Opens a Message box with a error message in it.  The user can               |
|   select the OK button to continue                                            |
\*----------------------------------------------------------------------------*/

int ErrMsg (LPSTR sz,...)
{
    static char szOutput[4*BUFSIZE];

    va_list va;

    va_start(va, sz);
    wvsprintf (szOutput,sz,va);      /* Format the string */
    va_end(va);
    MessageBox(NULL,szOutput,NULL, MB_OK|MB_ICONEXCLAMATION|MB_TASKMODAL);
    return FALSE;
}


/* AboutDlgProc()
 *
 * Dialog Procedure for the "about" dialog box.
 *
 */

BOOL CALLBACK AboutDlgProc(
                  HWND  hwnd,
                  UINT  msg,
                  WPARAM        wParam,
                  LPARAM        lParam)
{
    switch (msg) {
    case WM_COMMAND:
        EndDialog(hwnd, TRUE);
        return TRUE;
    case WM_INITDIALOG:
        return TRUE;
    }
    return FALSE;
}