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Turnbull China Bikeride
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Turnbull China Bikeride - Disc 2.iso
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STUTTGART
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SOUND
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MP3CONV
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!MP3Conv
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c
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common
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1997-04-01
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1,675 lines
/**********************************************************************
* ISO MPEG Audio Subgroup Software Simulation Group (1996)
* ISO 13818-3 MPEG-2 Audio Decoder - Lower Sampling Frequency Extension
*
* $Id: common.c,v 1.2 1996/03/28 03:13:37 rowlands Exp $
*
* $Log: common.c,v $
* Revision 1.2 1996/03/28 03:13:37 rowlands
* Merged layers 1-2 and layer 3 revisions
*
* Revision 1.1 1996/02/14 03:45:52 rowlands
* Initial revision
*
* Received from FhG
**********************************************************************/
/**********************************************************************
* date programmers comment *
* 2/25/91 Doulas Wong, start of version 1.0 records *
* Davis Pan *
* 5/10/91 W. Joseph Carter Created this file for all common *
* functions and global variables. *
* Ported to Macintosh and Unix. *
* Added Jean-Georges Fritsch's *
* "bitstream.c" package. *
* Added routines to handle AIFF PCM *
* sound files. *
* Added "mem_alloc()" and "mem_free()" *
* routines for memory allocation *
* portability. *
* Added routines to convert between *
* Apple SANE extended floating point *
* format and IEEE double precision *
* floating point format. For AIFF. *
* 02jul91 dpwe (Aware Inc) Moved allocation table input here; *
* Tables read from subdir TABLES_PATH. *
* Added some debug printout fns (Write*)*
* 7/10/91 Earle Jennings replacement of the one float by FLOAT *
* port to MsDos from MacIntosh version *
* 8/ 5/91 Jean-Georges Fritsch fixed bug in open_bit_stream_r() *
*10/ 1/91 S.I. Sudharsanan, Ported to IBM AIX platform. *
* Don H. Lee, *
* Peter W. Farrett *
*10/3/91 Don H. Lee implemented CRC-16 error protection *
* newly introduced functions are *
* I_CRC_calc, II_CRC_calc and *
* update_CRC. Additions and revisions *
* are marked with dhl for clarity *
*10/18/91 Jean-Georges Fritsch fixed bug in update_CRC(), *
* II_CRC_calc() and I_CRC_calc() *
* 2/11/92 W. Joseph Carter Ported new code to Macintosh. Most *
* important fixes involved changing *
* 16-bit ints to long or unsigned in *
* bit alloc routines for quant of 65535 *
* and passing proper function args. *
* Removed "Other Joint Stereo" option *
* and made bitrate be total channel *
* bitrate, irrespective of the mode. *
* Fixed many small bugs & reorganized. *
* 3/20/92 Jean-Georges Fritsch fixed bug in start-of-frame search *
* 6/15/92 Juan Pineda added refill_buffer(bs) "n" *
* initialization *
* 7/08/92 Susanne Ritscher MS-DOS, MSC6.0 port fixes *
* 7/27/92 Mike Li (re-)Port to MS-DOS *
* 8/19/92 Soren H. Nielsen Fixed bug in I_CRC_calc and in *
* II_CRC_calc. Added function: new_ext *
* for better MS-DOS compatability *
* 3/10/93 Kevin Peterson changed aiff_read_headers to handle *
* chunks in any order. now returns *
* position of sound data in file. *
* 3/31/93 Jens Spille changed IFF_* string compares to use *
* strcmp() *
* 5/30/93 Masahiro Iwadare removed the previous modification *
* for UNIX. *
* 8/27/93 Seymour Shlien, Fixes in Unix and MSDOS ports, *
* Daniel Lauzon, and *
* Bill Truerniet *
*--------------------------------------------------------------------*
* 8/24/93 Masahiro Iwadare Included IS modification in Layer III.*
* Changed for 1 pass decoding. *
* 9/07/93 Toshiyuki Ishino Integrated Layer III with Ver 3.9. *
*--------------------------------------------------------------------*
* 11/20/93 Masahiro Iwadare Integrated Layer III with Ver 4.0. *
*--------------------------------------------------------------------*
* 7/14/94 Juergen Koller rewind of bitbuffer added *
*--------------------------------------------------------------------*
* 6/12/95 Soeren H. Nielsen Bug fix in new_ext(). *
* 7/11/95 Soeren H. Nielsen Changes for MPEG-2 LSF Layer I and II *
*--------------------------------------------------------------------*
* 12/16/96 Johan Hagman Adapted for Solaris (mpeg3play 0.9) *
**********************************************************************/
/***********************************************************************
*
* Global Include Files
*
***********************************************************************/
#include "common.h"
#ifdef MACINTOSH
#include <SANE.h>
#include <pascal.h>
#endif
#include <string.h> /* 1995-07-11 shn */
#include <ctype.h>
/*-- Local declarations --*/
unsigned long sstell(Bit_stream_struc *);
/*-- External references --*/
extern char *programName;
extern Arguments_t Arguments;
/***********************************************************************
*
* Global Variable Definitions
*
***********************************************************************/
char *mode_names[5] = { "stereo", "j-stereo", "dual-ch", "single-ch" , "multi-ch"};
char *layer_names[3] = { "I", "II", "III" };
char *version_names[2] = { "MPEG-2 LSF", "MPEG-1" };
/* 1: MPEG-1, 0: MPEG-2 LSF, 1995-07-11 shn */
double s_freq[2][4] = {{22.05, 24, 16, 0}, {44.1, 48, 32, 0}};
/* 1: MPEG-1, 0: MPEG-2 LSF, 1995-07-11 shn */
int bitrate[2][3][15] = {{
{0,32,48,56,64,80,96,112,128,144,160,176,192,224,256},
{0,8,16,24,32,40,48,56,64,80,96,112,128,144,160},
{0,8,16,24,32,40,48,56,64,80,96,112,128,144,160}},
{{0,32,64,96,128,160,192,224,256,288,320,352,384,416,448},
{0,32,48,56,64,80,96,112,128,160,192,224,256,320,384},
{0,32,40,48,56,64,80,96,112,128,160,192,224,256,320}
}};
REAL FAR multiple[64] = {
2.00000000000000, 1.58740105196820, 1.25992104989487,
1.00000000000000, 0.79370052598410, 0.62996052494744, 0.50000000000000,
0.39685026299205, 0.31498026247372, 0.25000000000000, 0.19842513149602,
0.15749013123686, 0.12500000000000, 0.09921256574801, 0.07874506561843,
0.06250000000000, 0.04960628287401, 0.03937253280921, 0.03125000000000,
0.02480314143700, 0.01968626640461, 0.01562500000000, 0.01240157071850,
0.00984313320230, 0.00781250000000, 0.00620078535925, 0.00492156660115,
0.00390625000000, 0.00310039267963, 0.00246078330058, 0.00195312500000,
0.00155019633981, 0.00123039165029, 0.00097656250000, 0.00077509816991,
0.00061519582514, 0.00048828125000, 0.00038754908495, 0.00030759791257,
0.00024414062500, 0.00019377454248, 0.00015379895629, 0.00012207031250,
0.00009688727124, 0.00007689947814, 0.00006103515625, 0.00004844363562,
0.00003844973907, 0.00003051757813, 0.00002422181781, 0.00001922486954,
0.00001525878906, 0.00001211090890, 0.00000961243477, 0.00000762939453,
0.00000605545445, 0.00000480621738, 0.00000381469727, 0.00000302772723,
0.00000240310869, 0.00000190734863, 0.00000151386361, 0.00000120155435,
1E-20
};
/***********************************************************************
*
* Global Function Definitions
*
***********************************************************************/
#ifndef BUILTIN_TABLES
/* The system uses a variety of data files. By opening them via this
function, we can accommodate various locations. */
FILE *OpenTableFile(char *name)
{
char fulname[80];
char *envdir;
FILE *f;
fulname[0] = '\0';
#ifdef TABLES_PATH
strcpy(fulname, TABLES_PATH); /* default relative path for tables */
#endif /* TABLES_PATH */ /* (includes terminal path seperator */
#ifdef UNIX /* envir. variables for UNIX only */
{
char *getenv();
envdir = getenv(MPEGTABENV); /* check for environment */
if(envdir != NULL)
strcpy(fulname, envdir);
strcat(fulname, PATH_SEPARATOR); /* add a "/" on the end */
}
#endif /* UNIX */
strcat(fulname, name);
if( (f=fopen(fulname,"r"))==NULL ) {
fprintf(stderr,"OpenTable: could not find %s\n", fulname);
#ifdef UNIX
if(envdir != NULL)
fprintf(stderr,"Check %s directory '%s'\n",MPEGTABENV, envdir);
else
fprintf(stderr,"Check local directory './%s' or setenv %s\n",
TABLES_PATH, MPEGTABENV);
#else /* not unix : no environment variables */
#ifdef TABLES_PATH
fprintf(stderr,"Check local directory './%s'\n",TABLES_PATH);
#endif /* TABLES_PATH */
#endif /* UNIX */
}
return f;
}
/***********************************************************************
*
* Read one of the data files ("alloc_*") specifying the bit allocation/
* quatization parameters for each subband in layer II encoding
*
**********************************************************************/
int read_bit_alloc( /* read in table, return # subbands */
int table,
al_table *alloc)
{
unsigned int a, b, c, d, i, j;
FILE *fp;
char name[16], t[80];
int sblim;
strcpy(name, "alloc_0");
switch (table) {
case 0:
name[6] = '0';
break;
case 1:
name[6] = '1';
break;
case 2:
name[6] = '2';
break;
case 3:
name[6] = '3';
break;
case 4:
name[6] = '4';
break; /* LSF, added 1995-07-11 shn */
default:
name[6] = '0';
}
if (!(fp = OpenTableFile(name))) {
fprintf(stderr, "Please check bit allocation table %s\n", name);
exit(1);
}
/*if (Arguments.verbose)*/
/* printf("using bit allocation table %s\n", name);*/
fgets(t, 80, fp);
sscanf(t, "%d\n", &sblim);
while (!feof(fp)) {
fgets(t, 80, fp);
sscanf(t, "%d %d %d %d %d %d\n", &i, &j, &a, &b, &c, &d);
(*alloc)[i][j].steps = a;
(*alloc)[i][j].bits = b;
(*alloc)[i][j].group = c;
(*alloc)[i][j].quant = d;
}
fclose(fp);
return sblim;
}
#endif /* BUILTIN_TABLES*/
/***********************************************************************
*
* Using the decoded info the appropriate possible quantization per
* subband table is loaded
*
**********************************************************************/
int pick_table( /* choose table, load if necess, return # sb's */
frame_params *fr_ps)
{
int table, lay, ws, bsp, br_per_ch, sfrq,ver;
int sblim = fr_ps->sblimit; /* return current value if no load */
ver = fr_ps->header->version;
lay = fr_ps->header->lay - 1;
bsp = fr_ps->header->bitrate_index;
br_per_ch = bitrate[ver][lay][bsp] / fr_ps->stereo;
ws = fr_ps->header->sampling_frequency;
sfrq = (int)s_freq[ver][ws];
/* decision rules refer to per-channel bitrates (kbits/sec/chan) */
if (fr_ps->header->version == MPEG_AUDIO_ID) { /* MPEG-1 */
if ((sfrq == 48 && br_per_ch >= 56) ||
(br_per_ch >= 56 && br_per_ch <= 80)) table = 0;
else if (sfrq != 48 && br_per_ch >= 96) table = 1;
else if (sfrq != 32 && br_per_ch <= 48) table = 2;
else table = 3;
}
else { /* MPEG-2 LSF */
table = 4;
}
if (fr_ps->tab_num != table) {
if (fr_ps->tab_num >= 0)
mem_free((void **)&(fr_ps->alloc));
fr_ps->alloc = (al_table FAR *) mem_alloc(sizeof(al_table),
"alloc");
sblim = read_bit_alloc(fr_ps->tab_num = table, fr_ps->alloc);
}
return sblim;
}
int js_bound(int lay, int m_ext)
{
static int jsb_table[3][4] = { { 4, 8, 12, 16 }, { 4, 8, 12, 16},
{ 0, 4, 8, 16} }; /* lay+m_e -> jsbound */
if(lay<1 || lay >3 || m_ext<0 || m_ext>3) {
fprintf(stderr, "js_bound bad layer/modext (%d/%d)\n", lay, m_ext);
exit(1);
}
return(jsb_table[lay-1][m_ext]);
}
/*
* Interpret data in hdr str to fields in fr_ps
*/
void hdr_to_frps(
frame_params *fr_ps)
{
layer *hdr = fr_ps->header; /* (or pass in as arg?) */
fr_ps->actual_mode = hdr->mode;
fr_ps->stereo = (hdr->mode == MPG_MD_MONO) ? 1 : 2;
if (hdr->lay == 2)
fr_ps->sblimit = pick_table(fr_ps);
else
fr_ps->sblimit = SBLIMIT;
if (hdr->mode == MPG_MD_JOINT_STEREO)
fr_ps->jsbound = js_bound(hdr->lay, hdr->mode_ext);
else
fr_ps->jsbound = fr_ps->sblimit;
/* alloc, tab_num set in pick_table */
}
void WriteHdr(frame_params *fr_ps, FILE *s)
{
layer *info = fr_ps->header;
fprintf(s,
"hdr: s=FFF, id=%X, l=%X, ep=%s, br=%X, sf=%X, pd=%X, ",
info->version, info->lay,
((info->error_protection) ? "on" : "off"),
info->bitrate_index, info->sampling_frequency, info->padding);
fprintf(s, "pr=%X, m=%X, js=%X, c=%X,\n",
info->extension, info->mode, info->mode_ext, info->copyright);
fprintf(s, " o=%X, e=%X, alg=%s, layer=%s, tot bitrate=%d, sfrq=%.2f\n",
info->original, info->emphasis, version_names[info->version],
layer_names[info->lay-1],
bitrate[info->version][info->lay-1][info->bitrate_index],
s_freq[info->version][info->sampling_frequency]);
fprintf(s, " mode=%s, sblim=%d, jsbd=%d, ch=%d\n",
mode_names[info->mode], fr_ps->sblimit, fr_ps->jsbound, fr_ps->stereo);
fflush(s);
}
void WriteBitAlloc(unsigned int bit_alloc[2][SBLIMIT],
frame_params *f_p, FILE *s)
{
int i,j;
int st = f_p->stereo;
int sbl = f_p->sblimit;
int jsb = f_p->jsbound;
fprintf(s, "BITA ");
for(i=0; i<sbl; ++i) {
if(i == jsb) fprintf(s,"-");
for(j=0; j<st; ++j)
fprintf(s, "%1x", bit_alloc[j][i]);
}
fprintf(s, "\n"); fflush(s);
}
void WriteScale(unsigned int bit_alloc[2][SBLIMIT],
unsigned int scfsi[2][SBLIMIT], unsigned int scalar[2][3][SBLIMIT],
frame_params *fr_ps, FILE *s)
{
int stereo = fr_ps->stereo;
int sblimit = fr_ps->sblimit;
int lay = fr_ps->header->lay;
int i, j, k;
if (lay == 2) {
fprintf(s, "SFSI ");
for (i=0;i<sblimit;i++) for (k=0;k<stereo;k++)
if (bit_alloc[k][i]) fprintf(s,"%d",scfsi[k][i]);
fprintf(s, "\nSCFs ");
for (k=0;k<stereo;k++) {
for (i=0;i<sblimit;i++)
if (bit_alloc[k][i])
switch (scfsi[k][i]) {
case 0: for (j=0;j<3;j++)
fprintf(s,"%2d%c",scalar[k][j][i],
(j==2)?';':'-');
break;
case 1:
case 3: fprintf(s,"%2d-",scalar[k][0][i]);
fprintf(s,"%2d;",scalar[k][2][i]);
break;
case 2: fprintf(s,"%2d;",scalar[k][0][i]);
}
fprintf(s, "\n");
}
}
else { /* lay == 1 */
fprintf(s, "SCFs ");
for (i=0;i<sblimit;i++) for (k=0;k<stereo;k++)
if (bit_alloc[k][i]) fprintf(s,"%2d;",scalar[k][0][i]);
fprintf(s, "\n");
}
}
void WriteSamples(int ch, unsigned int FAR sample[SBLIMIT],
unsigned int bit_alloc[SBLIMIT], frame_params *fr_ps, FILE *s)
{
int i;
int stereo = fr_ps->stereo;
int sblimit = fr_ps->sblimit;
fprintf(s, "SMPL ");
for (i=0;i<sblimit;i++)
if ( bit_alloc[i] != 0)
fprintf(s, "%d:", sample[i]);
if (ch==(stereo-1) ) fprintf(s, "\n");
else fprintf(s, "\t");
}
int NumericQ(char *s) /* see if a string lookd like a numeric argument */
{
char c;
while( (c = *s++)!='\0' && isspace((int)c)) /* strip leading ws */
;
if( c == '+' || c == '-' )
c = *s++; /* perhaps skip leading + or - */
return isdigit((int)c);
}
int BitrateIndex( /* convert bitrate in kbps to index */
int ver, /* 1 or 2 */
int layr,
int bRate) /* legal rates from 32 to 448 */
{
int index = 0;
int found = 0;
while(!found && index<15) {
if(bitrate[ver][layr-1][index] == bRate)
found = 1;
else
++index;
}
if(found)
return(index);
else {
fprintf(stderr, "BitrateIndex: %d (layer %d) is not a legal bitrate\n",
bRate, layr);
return(-1); /* Error! */
}
}
int SmpFrqIndex( /* convert samp frq in Hz to index */
long sRate, /* legal rates 16000, 22050, 24000, 32000, 44100, 48000 */
int *version)
{
if (sRate == 44100L) {
*version = MPEG_AUDIO_ID; return(0);
}
else if (sRate == 48000L) {
*version = MPEG_AUDIO_ID; return(1);
}
else if (sRate == 32000L) {
*version = MPEG_AUDIO_ID; return(2);
}
else if (sRate == 24000L) {
*version = MPEG_PHASE2_LSF; return(1);
}
else if (sRate == 22050L) {
*version = MPEG_PHASE2_LSF; return(0);
}
else if (sRate == 16000L) {
*version = MPEG_PHASE2_LSF; return(2);
}
else {
fprintf(stderr, "SmpFrqIndex: %ld is not a legal sample rate\n", sRate);
return(-1); /* Error! */
}
}
/*******************************************************************************
*
* Allocate number of bytes of memory equal to "block".
*
*******************************************************************************/
void FAR *mem_alloc(unsigned long block, char *item)
{
void *ptr;
#ifdef MACINTOSH
ptr = NewPtr(block);
#endif
#ifdef MSC60
/*ptr = (void FAR *) _fmalloc((unsigned int)block);*/ /* far memory, 92-07-08 sr */
ptr = (void FAR *) malloc((unsigned int)block); /* far memory, 93-08-24 ss */
#endif
#if ! defined (MACINTOSH) && ! defined (MSC60)
ptr = (void FAR *) malloc(block);
#endif
if (ptr != NULL){
#ifdef MSC60
_fmemset(ptr, 0, (unsigned int)block); /* far memory, 92-07-08 sr */
#else
memset(ptr, 0, block);
#endif
}
else {
fprintf(stderr, "Unable to allocate %s\n", item);
exit(0);
}
return(ptr);
}
/****************************************************************************
*
* Free memory pointed to by "*ptr_addr".
*
*****************************************************************************/
void mem_free(void **ptr_addr)
{
if (*ptr_addr != NULL){
#ifdef MACINTOSH
DisposPtr(*ptr_addr);
#else
free(*ptr_addr);
#endif
*ptr_addr = NULL;
}
}
/*******************************************************************************
*
* Check block of memory all equal to a single byte, else return FALSE
*
*******************************************************************************/
int memcheck(char *array,
int test, /* but only tested as a char (bottom 8 bits) */
int num)
{
int i=0;
while (array[i] == test && i<num) i++;
if (i==num) return TRUE;
else return FALSE;
}
/*****************************************************************************
*
* Routines to determine byte order and swap bytes
*
*****************************************************************************/
enum byte_order NativeByteOrder = order_unknown;
enum byte_order DetermineByteOrder()
{
char s[ sizeof(long) + 1 ];
union
{
long longval;
char charval[ sizeof(long) ];
} probe;
probe.longval = 0x41424344L; /* ABCD in ASCII */
strncpy( s, probe.charval, sizeof(long) );
s[ sizeof(long) ] = '\0';
/* fprintf( stderr, "byte order is %s\n", s ); */
if ( strcmp(s, "ABCD") == 0 )
return order_bigEndian;
else
if ( strcmp(s, "DCBA") == 0 )
return order_littleEndian;
else
return order_unknown;
}
void SwapBytesInWords(short *loc, int words)
{
int i;
unsigned char *src = (unsigned char *)loc;
unsigned char tmp;
for (i = 0; i < words; i++) {
tmp = src[0];
src[0] = src[1];
src[1] = tmp;
src += 2;
}
}
/*****************************************************************************
*
* Read Audio Interchange File Format (AIFF) headers.
*
*****************************************************************************/
int aiff_read_headers(FILE *file_ptr, IFF_AIFF *aiff_ptr)
{
int chunkSize, subSize, sound_position;
if ( fseek(file_ptr, 0, SEEK_SET) != 0 )
return -1;
if ( Read32BitsHighLow(file_ptr) != IFF_ID_FORM )
return -1;
chunkSize = Read32BitsHighLow( file_ptr );
if ( Read32BitsHighLow(file_ptr) != IFF_ID_AIFF )
return -1;
sound_position = 0;
while ( chunkSize > 0 )
{
chunkSize -= 4;
switch ( Read32BitsHighLow(file_ptr) )
{
case IFF_ID_COMM:
chunkSize -= subSize = Read32BitsHighLow( file_ptr );
aiff_ptr->numChannels = Read16BitsHighLow( file_ptr );
subSize -= 2;
aiff_ptr->numSampleFrames = Read32BitsHighLow( file_ptr );
subSize -= 4;
aiff_ptr->sampleSize = Read16BitsHighLow( file_ptr );
subSize -= 2;
aiff_ptr->sampleRate = ReadIeeeExtendedHighLow( file_ptr );
subSize -= 10;
while ( subSize > 0 )
{
getc( file_ptr );
subSize -= 1;
}
break;
case IFF_ID_SSND:
chunkSize -= subSize = Read32BitsHighLow( file_ptr );
aiff_ptr->blkAlgn.offset = Read32BitsHighLow( file_ptr );
subSize -= 4;
aiff_ptr->blkAlgn.blockSize = Read32BitsHighLow( file_ptr );
subSize -= 4;
sound_position = ftell( file_ptr ) + aiff_ptr->blkAlgn.offset;
if ( fseek(file_ptr, (long) subSize, SEEK_CUR) != 0 )
return -1;
aiff_ptr->sampleType = IFF_ID_SSND;
break;
default:
chunkSize -= subSize = Read32BitsHighLow( file_ptr );
while ( subSize > 0 )
{
getc( file_ptr );
subSize -= 1;
}
break;
}
}
return sound_position;
}
/*****************************************************************************
*
* Seek past some Audio Interchange File Format (AIFF) headers to sound data.
*
*****************************************************************************/
int aiff_seek_to_sound_data(FILE *file_ptr)
{
if ( fseek(file_ptr, AIFF_FORM_HEADER_SIZE + AIFF_SSND_HEADER_SIZE, SEEK_SET) != 0 )
return(-1);
return 0;
}
/*****************************************************************************
*
* Write Audio Interchange File Format (AIFF) headers.
*
*****************************************************************************/
int aiff_write_headers(FILE *file_ptr, IFF_AIFF *aiff_ptr)
{
int chunkSize;
int sampleBytes = (aiff_ptr->sampleSize / 8) +
(aiff_ptr->sampleSize % 8 ? 1 : 0);
/* Seek back to beginning */
if (fseek(file_ptr, 0L, SEEK_SET) != 0)
return -1;
/* Write FORM chunk */
chunkSize = 8 + 18 + 8 + aiff_ptr->numChannels *
aiff_ptr->numSampleFrames * sampleBytes;
Write32BitsHighLow( file_ptr, IFF_ID_FORM );
Write32BitsHighLow( file_ptr, chunkSize );
Write32BitsHighLow( file_ptr, IFF_ID_AIFF );
/* Write COMM chunk */
Write32BitsHighLow( file_ptr, IFF_ID_COMM );
Write32BitsHighLow( file_ptr, 18 ); /* chunk size*/
Write16BitsHighLow( file_ptr, aiff_ptr->numChannels );
Write32BitsHighLow( file_ptr, aiff_ptr->numSampleFrames );
Write16BitsHighLow( file_ptr, aiff_ptr->sampleSize );
WriteIeeeExtendedHighLow( file_ptr, aiff_ptr->sampleRate );
/* Write SSND chunk header */
chunkSize = 8 + aiff_ptr->numChannels * aiff_ptr->numSampleFrames *
sampleBytes;
Write32BitsHighLow( file_ptr, IFF_ID_SSND );
Write32BitsHighLow( file_ptr, chunkSize );
Write32BitsHighLow( file_ptr, 0 ); /* offset*/
Write32BitsHighLow( file_ptr, 0 ); /* block size*/
return 0;
}
/*****************************************************************************
*
* bit_stream.c package
* Author: Jean-Georges Fritsch, C-Cube Microsystems
*
*****************************************************************************/
/********************************************************************
This package provides functions to write (exclusive or read)
information from (exclusive or to) the bit stream.
If the bit stream is opened in read mode only the get functions are
available. If the bit stream is opened in write mode only the put
functions are available.
********************************************************************/
/*open_bit_stream_w(); open the device to write the bit stream into it */
/*open_bit_stream_r(); open the device to read the bit stream from it */
/*close_bit_stream(); close the device containing the bit stream */
/*alloc_buffer(); open and initialize the buffer; */
/*desalloc_buffer(); empty and close the buffer */
/*back_track_buffer(); goes back N bits in the buffer */
/*unsigned int get1bit(); read 1 bit from the bit stream */
/*unsigned long getbits(); read N bits from the bit stream */
/*unsigned long byte_ali_getbits(); read the next byte aligned N bits from*/
/* the bit stream */
/*unsigned long look_ahead(); grep the next N bits in the bit stream without*/
/* changing the buffer pointer */
/*put1bit(); write 1 bit from the bit stream */
/*put1bit(); write 1 bit from the bit stream */
/*putbits(); write N bits from the bit stream */
/*byte_ali_putbits(); write byte aligned the next N bits into the bit stream*/
/*unsigned long sstell(); return the current bit stream length (in bits) */
/*int end_bs(); return 1 if the end of bit stream reached otherwise 0 */
/*int seek_sync(); return 1 if a sync word was found in the bit stream */
/* otherwise returns 0 */
/* refill the buffer from the input device when the buffer becomes empty */
void refill_buffer(Bit_stream_struc *bs) /* bit stream structure */
{
int i = bs->buf_size - 2 - bs->buf_byte_idx;
unsigned long n = 1;
int index = 0;
char val[2];
#ifdef OPTIMIZE
# define RBUFSIZE 8192
static unsigned char readbuf[RBUFSIZE];
if (bs->format == BINARY) {
while (i >= 0 && (!bs->eob)) {
int j;
/* Try to read many bytes in each call to fread()*/
if (i > RBUFSIZE)
n = fread(readbuf, sizeof(unsigned char), RBUFSIZE, bs->pt);
else
n = fread(readbuf, sizeof(unsigned char), i + 1, bs->pt);
/* Copy the read buffer*/
for (j = 0; i >= 0 && j < n; j++)
bs->buf[i--] = readbuf[j];
if (n == 0 && feof(bs->pt))
bs->eob = i + 1; /* eof*/
}
} else {
while ((i>=0) && (!bs->eob)) {
while((index < 2) && n) {
n = fread(&val[index], sizeof(char), 1, bs->pt);
switch (val[index]) {
case 0x30:
case 0x31:
case 0x32:
case 0x33:
case 0x34:
case 0x35:
case 0x36:
case 0x37:
case 0x38:
case 0x39:
case 0x41:
case 0x42:
case 0x43:
case 0x44:
case 0x45:
case 0x46:
index++;
break;
default:
break;
}
}
if (val[0] <= 0x39)
bs->buf[i] = (val[0] - 0x30) << 4;
else
bs->buf[i] = (val[0] - 0x37) << 4;
if (val[1] <= 0x39)
bs->buf[i--] |= (val[1] - 0x30);
else
bs->buf[i--] |= (val[1] - 0x37);
index = 0;
if (!n)
bs->eob= i+1;
}
}
#else
/* Original code*/
while ((i>=0) && (!bs->eob)) {
if (bs->format == BINARY)
n = fread(&bs->buf[i--], sizeof(unsigned char), 1, bs->pt);
else {
while((index < 2) && n) {
n = fread(&val[index], sizeof(char), 1, bs->pt);
switch (val[index]) {
case 0x30:
case 0x31:
case 0x32:
case 0x33:
case 0x34:
case 0x35:
case 0x36:
case 0x37:
case 0x38:
case 0x39:
case 0x41:
case 0x42:
case 0x43:
case 0x44:
case 0x45:
case 0x46:
index++;
break;
default:
break;
}
}
if (val[0] <= 0x39)
bs->buf[i] = (val[0] - 0x30) << 4;
else
bs->buf[i] = (val[0] - 0x37) << 4;
if (val[1] <= 0x39)
bs->buf[i--] |= (val[1] - 0x30);
else
bs->buf[i--] |= (val[1] - 0x37);
index = 0;
}
if (!n)
bs->eob= i+1;
}
#endif /* OPTIMIZE*/
}
#if BS_FORMAT != BINARY
static char *he = "0123456789ABCDEF";
#endif
/*
* Empty the buffer to the output device when the buffer becomes full
*/
void empty_buffer(
Bit_stream_struc *bs, /* bit stream structure */
int minimum) /* end of the buffer to empty */
{
int i;
#if BS_FORMAT == BINARY
for (i=bs->buf_size-1;i>=minimum;i--)
fwrite(&bs->buf[i], sizeof(unsigned char), 1, bs->pt);
#else
for (i=bs->buf_size-1;i>=minimum;i--) {
char val[2];
val[0] = he[((bs->buf[i] >> 4) & 0x0F)];
val[1] = he[(bs->buf[i] & 0x0F)];
fwrite(val, sizeof(char), 2, bs->pt);
}
#endif
for (i=minimum-1; i>=0; i--)
bs->buf[bs->buf_size - minimum + i] = bs->buf[i];
bs->buf_byte_idx = bs->buf_size -1 - minimum;
bs->buf_bit_idx = 8;
}
/*
* Open the device to write the bit stream into it
*/
void open_bit_stream_w(
Bit_stream_struc *bs, /* bit stream structure */
char *bs_filenam, /* name of the bit stream file */
int size) /* size of the buffer */
{
if ((bs->pt = fopen(bs_filenam, "wb")) == NULL) {
fprintf(stderr, "Could not create \"%s\"\n", bs_filenam);
exit(1);
}
alloc_buffer(bs, size);
bs->buf_byte_idx = size-1;
bs->buf_bit_idx=8;
bs->totbit=0;
bs->mode = WRITE_MODE;
bs->eob = FALSE;
bs->eobs = FALSE;
}
/*
* Open the device to read the bit stream from it
*/
void open_bit_stream_r(
Bit_stream_struc *bs, /* bit stream structure */
char *bs_filenam, /* name of the bit stream file */
int size) /* size of the buffer */
{
unsigned long n;
unsigned char flag = 1;
unsigned char val;
unsigned char ungetBuf[10]; /* max # chars we can ungetc()*/
int nungetc;
if (strcmp(bs_filenam, "-") == 0) {
/* Read stdin*/
if ((bs->pt = fdopen(0, "rb")) == NULL) {
fprintf(stderr, "%s: could not open stdin\n", programName);
exit(1);
}
} else {
/* Read a file*/
if ((bs->pt = fopen(bs_filenam, "rb")) == NULL) {
fprintf(stderr, "%s: could not find \"%s\"\n",
programName, bs_filenam);
exit(1);
}
}
nungetc = 0;
do {
n = fread(&val, sizeof(unsigned char), 1, bs->pt);
ungetBuf[nungetc++] = val; /* save for pushback to stream*/
switch (val) {
case 0x30:
case 0x31:
case 0x32:
case 0x33:
case 0x34:
case 0x35:
case 0x36:
case 0x37:
case 0x38:
case 0x39:
case 0x41:
case 0x42:
case 0x43:
case 0x44:
case 0x45:
case 0x46:
case 0xa: /* \n */
case 0xd: /* cr */
case 0x1a: /* sub */
break;
default: /* detection of an binary character */
flag--;
break;
}
} while ((flag & n) && nungetc < 10);
if (flag) {
if (Arguments.verbose)
fprintf(stderr, "The bit stream file %s is an ascii file\n", bs_filenam);
bs->format = ASCII;
} else {
if (Arguments.verbose) {
if (strcmp(bs_filenam, "-") == 0)
fprintf(stderr, "The input bit stream is binary\n");
else
fprintf(stderr, "The bit stream file \"%s\" is a binary file\n",
bs_filenam);
}
bs->format = BINARY;
}
if (strcmp(bs_filenam, "-") == 0) {
/* Cannot rewind a pipe, push back character instead.*/
/* Only four bytes are actually guaranteed to ungetc().*/
while (nungetc > 0)
ungetc(ungetBuf[--nungetc], bs->pt);
} else {
fclose(bs->pt);
if ((bs->pt = fopen(bs_filenam, "rb")) == NULL) {
fprintf(stderr, "%s: could not find \"%s\"\n",
programName, bs_filenam);
exit(1);
}
}
alloc_buffer(bs, size);
bs->buf_byte_idx=0;
bs->buf_bit_idx=0;
bs->totbit=0;
bs->mode = READ_MODE;
bs->eob = FALSE;
bs->eobs = FALSE;
}
/* Close the device containing the bit stream after a read process*/
void close_bit_stream_r(Bit_stream_struc *bs) /* bit stream structure */
{
fclose(bs->pt);
desalloc_buffer(bs);
}
/* Close the device containing the bit stream after a write process*/
void close_bit_stream_w(Bit_stream_struc *bs) /* bit stream structure */
{
empty_buffer(bs, bs->buf_byte_idx);
fclose(bs->pt);
desalloc_buffer(bs);
}
/* Open and initialize the buffer; */
void alloc_buffer(
Bit_stream_struc *bs, /* bit stream structure */
int size)
{
bs->buf = (unsigned char FAR *) mem_alloc(size*sizeof(unsigned
char), "buffer");
bs->buf_size = size;
}
/* Empty and close the buffer */
void desalloc_buffer(Bit_stream_struc *bs) /* bit stream structure */
{
free(bs->buf);
}
int putmask[9] = {0x0, 0x1, 0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f, 0xff};
int clearmask[9] = {0xff, 0xfe, 0xfc, 0xf8, 0xf0, 0xe0, 0xc0, 0x80, 0x0};
void back_track_buffer( /* goes back N bits in the buffer */
Bit_stream_struc *bs, /* bit stream structure */
int N)
{
int tmp = N - (N/8)*8;
int i;
bs->totbit -= N;
for (i=bs->buf_byte_idx;i< bs->buf_byte_idx+N/8-1;i++) bs->buf[i] = 0;
bs->buf_byte_idx += N/8;
if ( (tmp + bs->buf_bit_idx) <= 8) {
bs->buf_bit_idx += tmp;
}
else {
bs->buf_byte_idx ++;
bs->buf_bit_idx += (tmp - 8);
}
bs->buf[bs->buf_byte_idx] &= clearmask[bs->buf_bit_idx];
}
int mask[8]={0x1, 0x2, 0x4, 0x8, 0x10, 0x20, 0x40, 0x80};
/*
* Read 1 bit from the bit stream
*/
unsigned int get1bit(Bit_stream_struc *bs) /* bit stream structure */
{
unsigned int bit;
int i;
bs->totbit++;
if (!bs->buf_bit_idx) {
bs->buf_bit_idx = 8;
bs->buf_byte_idx--;
if ((bs->buf_byte_idx < MINIMUM) || (bs->buf_byte_idx < bs->eob)) {
if (bs->eob)
bs->eobs = TRUE;
else {
for (i = bs->buf_byte_idx; i >= 0; i--)
bs->buf[bs->buf_size-1-bs->buf_byte_idx+i] = bs->buf[i];
refill_buffer(bs);
bs->buf_byte_idx = bs->buf_size-1;
}
}
}
bit = bs->buf[bs->buf_byte_idx] & mask[bs->buf_bit_idx-1];
bit = bit >> (bs->buf_bit_idx-1);
bs->buf_bit_idx--;
return bit;
}
/*
* Write 1 bit from the bit stream
*/
void put1bit(
Bit_stream_struc *bs, /* bit stream structure */
int bit) /* bit to write into the buffer */
{
bs->totbit++;
bs->buf[bs->buf_byte_idx] |= (bit&0x1) << (bs->buf_bit_idx-1);
bs->buf_bit_idx--;
if (!bs->buf_bit_idx) {
bs->buf_bit_idx = 8;
bs->buf_byte_idx--;
if (bs->buf_byte_idx < 0)
empty_buffer(bs, MINIMUM);
bs->buf[bs->buf_byte_idx] = 0;
}
}
/*
* Look ahead for the next N bits from the bit stream
*/
unsigned long look_ahead(
Bit_stream_struc *bs, /* bit stream structure */
int N) /* number of bits to read from the bit stream */
{
unsigned long val = 0;
int j = N;
int k, tmp;
int bit_idx = bs->buf_bit_idx;
int byte_idx = bs->buf_byte_idx;
#ifndef OPTIMIZE
if (N > MAX_LENGTH)
fprintf(stderr, "Cannot read or write more than %d bits at a time.\n",
MAX_LENGTH);
#endif
while (j > 0) {
if (!bit_idx) {
bit_idx = 8;
byte_idx--;
}
k = MIN(j, bit_idx);
tmp = bs->buf[byte_idx]&putmask[bit_idx];
tmp = tmp >> (bit_idx-k);
val |= tmp << (j-k);
bit_idx -= k;
j -= k;
}
return val;
}
/*
* Read N bit from the bit stream
*/
unsigned long getbits(
Bit_stream_struc *bs, /* bit stream structure */
int N) /* number of bits to read from the bit stream */
{
unsigned long val = 0;
int i;
int j = N;
int k;
#ifndef OPTIMIZE
int tmp;
if (N > MAX_LENGTH)
fprintf(stderr, "Cannot read/write more than %d bits at a time\n", MAX_LENGTH);
#endif
bs->totbit += N;
while (j > 0) {
if (!bs->buf_bit_idx) {
bs->buf_bit_idx = 8;
bs->buf_byte_idx--;
if ((bs->buf_byte_idx < MINIMUM) || (bs->buf_byte_idx < bs->eob)) {
if (bs->eob)
bs->eobs = TRUE;
else {
for (i=bs->buf_byte_idx; i>=0;i--)
bs->buf[bs->buf_size-1-bs->buf_byte_idx+i] = bs->buf[i];
refill_buffer(bs);
bs->buf_byte_idx = bs->buf_size-1;
}
}
}
k = MIN(j, bs->buf_bit_idx);
#ifdef OPTIMIZE
val |= ((int)(bs->buf[bs->buf_byte_idx] & putmask[bs->buf_bit_idx]) >>
(bs->buf_bit_idx - k)) << (j - k);
#else
tmp = bs->buf[bs->buf_byte_idx] & putmask[bs->buf_bit_idx];
tmp = tmp >> (bs->buf_bit_idx-k);
val |= tmp << (j-k);
#endif
bs->buf_bit_idx -= k;
j -= k;
}
return val;
}
/* Write N bits into the bit stream */
void putbits(
Bit_stream_struc *bs, /* bit stream structure */
unsigned int val, /* val to write into the buffer */
int N) /* number of bits of val */
{
int j = N;
int k, tmp;
if (N > MAX_LENGTH)
fprintf(stderr, "Cannot read or write more than %d bits at a time.\n", MAX_LENGTH);
bs->totbit += N;
while (j > 0) {
k = MIN(j, bs->buf_bit_idx);
tmp = val >> (j-k);
bs->buf[bs->buf_byte_idx] |= (tmp&putmask[k]) << (bs->buf_bit_idx-k);
bs->buf_bit_idx -= k;
if (!bs->buf_bit_idx) {
bs->buf_bit_idx = 8;
bs->buf_byte_idx--;
if (bs->buf_byte_idx < 0)
empty_buffer(bs, MINIMUM);
bs->buf[bs->buf_byte_idx] = 0;
}
j -= k;
}
}
/* Write N bits byte aligned into the bit stream */
void byte_ali_putbits(
Bit_stream_struc *bs, /* bit stream structure */
unsigned int val, /* val to write into the buffer */
int N) /* number of bits of val */
{
unsigned long aligning;
if (N > MAX_LENGTH)
fprintf(stderr, "Cannot read or write more than %d bits at a time.\n", MAX_LENGTH);
aligning = sstell(bs)%8;
if (aligning)
putbits(bs, (unsigned int)0, (int)(8-aligning));
putbits(bs, val, N);
}
/* Read the next bute aligned N bits from the bit stream */
unsigned long byte_ali_getbits(
Bit_stream_struc *bs, /* bit stream structure */
int N) /* number of bits of val */
{
unsigned long aligning;
if (N > MAX_LENGTH)
fprintf(stderr, "Cannot read or write more than %d bits at a time.\n", MAX_LENGTH);
aligning = sstell(bs)%8;
if (aligning)
getbits(bs, (int)(8-aligning));
return(getbits(bs, N));
}
/* Return the current bit stream length (in bits)*/
unsigned long sstell(Bit_stream_struc *bs) /* bit stream structure */
{
return(bs->totbit);
}
/* Return the status of the bit stream */
/* returns 1 if end of bit stream was reached */
/* returns 0 if end of bit stream was not reached */
int end_bs(Bit_stream_struc *bs) /* bit stream structure */
{
return(bs->eobs);
}
/*
* This function seeks for a byte aligned sync word in the bit stream and
* places the bit stream pointer right after the sync.
* This function returns 1 if the sync was found otherwise it returns 0
*/
int seek_sync(
Bit_stream_struc *bs, /* bit stream structure */
long sync, /* sync word maximum 32 bits */
int N) /* sync word length */
{
unsigned long aligning;
unsigned long val;
#ifdef OPTIMIZE
/* main() *always* calls this routine with N = SYNC_WORD_LNGTH = 12*/
/* This is really easy to optimize :-)*/
long maxi = 4095; /*(long)pow(2.0, (float)N) - 1;*/
aligning = bs->totbit & (ALIGNING - 1); /* ALIGNING equals 8*/
if (aligning)
getbits(bs, ALIGNING-aligning);
#else
long maxi = (long)pow(2.0, (float)N) - 1;
aligning = sstell(bs)%ALIGNING;
if (aligning)
getbits(bs, (int)(ALIGNING-aligning));
#endif
val = getbits(bs, N);
while (((val & maxi) != sync) && (!end_bs(bs))) {
val <<= ALIGNING;
val |= getbits(bs, ALIGNING);
}
if (end_bs(bs))
return 0;
else
return 1;
}
/*****************************************************************************
*
* End of bit_stream.c package
*
*****************************************************************************/
/*****************************************************************************
*
* CRC error protection package
*
*****************************************************************************/
void I_CRC_calc(
frame_params *fr_ps,
unsigned int bit_alloc[2][SBLIMIT],
unsigned int *crc)
{
int i, k;
layer *info = fr_ps->header;
int stereo = fr_ps->stereo;
int jsbound = fr_ps->jsbound;
*crc = 0xffff; /* changed from '0' 92-08-11 shn */
update_CRC(info->bitrate_index, 4, crc);
update_CRC(info->sampling_frequency, 2, crc);
update_CRC(info->padding, 1, crc);
update_CRC(info->extension, 1, crc);
update_CRC(info->mode, 2, crc);
update_CRC(info->mode_ext, 2, crc);
update_CRC(info->copyright, 1, crc);
update_CRC(info->original, 1, crc);
update_CRC(info->emphasis, 2, crc);
for (i=0;i<SBLIMIT;i++)
for (k=0;k<((i<jsbound)?stereo:1);k++)
update_CRC(bit_alloc[k][i], 4, crc);
}
void II_CRC_calc(
frame_params *fr_ps,
unsigned int bit_alloc[2][SBLIMIT],
unsigned int scfsi[2][SBLIMIT],
unsigned int *crc)
{
int i, k;
layer *info = fr_ps->header;
int stereo = fr_ps->stereo;
int sblimit = fr_ps->sblimit;
int jsbound = fr_ps->jsbound;
al_table *alloc = fr_ps->alloc;
#ifdef OPTIMIZE
unsigned int lcrc = 0xffff;
update_CRC(info->bitrate_index, 4, &lcrc);
update_CRC(info->sampling_frequency, 2, &lcrc);
update_CRC(info->padding, 1, &lcrc);
update_CRC(info->extension, 1, &lcrc);
update_CRC(info->mode, 2, &lcrc);
update_CRC(info->mode_ext, 2, &lcrc);
update_CRC(info->copyright, 1, &lcrc);
update_CRC(info->original, 1, &lcrc);
update_CRC(info->emphasis, 2, &lcrc);
/* Combine loops into one*/
for (i = 0; i < sblimit; i++)
for (k = 0; k < stereo; k++) {
if (bit_alloc[k][i])
update_CRC(scfsi[k][i], 2, &lcrc);
if (i < jsbound || k == 0)
update_CRC(bit_alloc[k][i], (*alloc)[i][0].bits, &lcrc);
}
*crc = lcrc; /* update once*/
#else
/* Original code*/
*crc = 0xffff; /* changed from '0' 92-08-11 shn */
update_CRC(info->bitrate_index, 4, crc);
update_CRC(info->sampling_frequency, 2, crc);
update_CRC(info->padding, 1, crc);
update_CRC(info->extension, 1, crc);
update_CRC(info->mode, 2, crc);
update_CRC(info->mode_ext, 2, crc);
update_CRC(info->copyright, 1, crc);
update_CRC(info->original, 1, crc);
update_CRC(info->emphasis, 2, crc);
for (i = 0; i < sblimit; i++)
for (k = 0; k < ((i < jsbound) ? stereo : 1); k++)
update_CRC(bit_alloc[k][i], (*alloc)[i][0].bits, crc);
for (i = 0; i < sblimit; i++)
for (k = 0; k < stereo; k++)
if (bit_alloc[k][i])
update_CRC(scfsi[k][i], 2, crc);
#endif /* OPTIMIZE*/
}
void update_CRC(unsigned int data, unsigned int length, unsigned int *crc)
{
unsigned int masking, carry;
masking = 1 << length;
while((masking >>= 1)) {
carry = *crc & 0x8000;
*crc <<= 1;
if (!carry ^ !(data & masking))
*crc ^= CRC16_POLYNOMIAL;
}
*crc &= 0xffff;
}
/*****************************************************************************
*
* End of CRC error protection package
*
*****************************************************************************/
#ifdef MACINTOSH
/*****************************************************************************
*
* Set Macintosh file attributes.
*
*****************************************************************************/
void set_mac_file_attr(fileName, vRefNum, creator, fileType)
char fileName[MAX_NAME_SIZE];
short vRefNum;
OsType creator;
OsType fileType;
{
short theFile;
char pascal_fileName[MAX_NAME_SIZE];
FInfo fndrInfo;
CtoPstr(strcpy(pascal_fileName, fileName));
FSOpen(pascal_fileName, vRefNum, &theFile);
GetFInfo(pascal_fileName, vRefNum, &fndrInfo);
fndrInfo.fdCreator = creator;
fndrInfo.fdType = fileType;
SetFInfo(pascal_fileName, vRefNum, &fndrInfo);
FSClose(theFile);
}
#endif /* MACINTOSH*/
#ifdef MS_DOS
/* ------------------------------------------------------------------------
new_ext()
Puts a new extension name on a file name <filename>.
Removes the last extension name, if any.
1992-08-19, 1995-06-12 shn
------------------------------------------------------------------------ */
char *new_ext(char *filename, char *extname)
{
int found, dotpos;
static char newname[80];
/* First, strip the extension */
dotpos=strlen(filename); found=0;
do
{
switch (filename[dotpos])
{
case '.' : found=1; break;
case '\\': /* used by MS-DOS */
case '/' : /* used by UNIX */
case ':' : found=-1; break; /* used by MS-DOS in drive designation */
default : dotpos--; if (dotpos<0) found=-1; break;
}
} while (found==0);
if (found==-1) strcpy(newname,filename);
if (found== 1) strncpy(newname,filename,dotpos); newname[dotpos]='\0';
strcat(newname,extname);
return(newname);
}
#endif /* MS_DOS*/
#define BUFSIZE 4096
/* Assembly routines require these to be global*/
unsigned long offset,totbit=0, buf_byte_idx=0;
unsigned int buf[BUFSIZE];
unsigned int buf_bit_idx=8;
/* Return the current bit stream length (in bits) */
unsigned long hsstell()
{
return(totbit);
}
extern int putmask[9];
/*
* read N bit from the bit stream
*/
unsigned long hgetbits(int N) /* number of bits to read from the bit stream */
{
unsigned long val = 0;
int j = N;
int k;
#ifndef OPTIMIZE
int tmp;
#endif
/*
* if (N > MAX_LENGTH)
* fprintf(stderr, "Cannot read or write more than %d bits at a time.\n",
* MAX_LENGTH);
*/
totbit += N;
while (j > 0) {
if (!buf_bit_idx) {
buf_bit_idx = 8;
buf_byte_idx++;
if (buf_byte_idx > offset) {
fprintf(stderr, "Buffer overflow !!\n");exit(3);
}
}
k = MIN(j, buf_bit_idx);
#ifdef OPTIMIZE
val |= ((buf[buf_byte_idx & (BUFSIZE-1)] & putmask[buf_bit_idx]) >>
(buf_bit_idx - k)) << (j - k);
#else
tmp = buf[buf_byte_idx%BUFSIZE]&putmask[buf_bit_idx];
tmp = tmp >> (buf_bit_idx-k);
val |= tmp << (j-k);
#endif
buf_bit_idx -= k;
j -= k;
}
return(val);
}
unsigned int hget1bit()
{
#ifdef OPTIMIZE
unsigned int val;
totbit++;
if (buf_bit_idx == 0) {
buf_bit_idx = 8;
buf_byte_idx++;
if (buf_byte_idx > offset) {
fprintf(stderr, "Buffer overflow!!\n");
exit(3);
}
}
val = ((buf[buf_byte_idx & (BUFSIZE-1)] & putmask[buf_bit_idx]) >>
(buf_bit_idx - 1));
buf_bit_idx--;
return(val);
#else
return(hgetbits(1));
#endif
}
/* Write N bits into the bit stream */
void hputbuf(
unsigned int val, /* val to write into the buffer */
int N) /* number of bits of val */
{
if (N != 8) { fprintf(stderr, "Not Supported yet!!\n"); exit(-3); }
buf[offset % BUFSIZE] = val;
offset++;
}
void rewindNbits(int N)
{
totbit -= N;
buf_bit_idx += N;
while( buf_bit_idx >= 8 )
{ buf_bit_idx -= 8;
buf_byte_idx--;
}
}
void rewindNbytes(int N)
{
totbit -= N*8;
buf_byte_idx -= N;
}