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SGI Developer Toolbox 6.1
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libtiff
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tif_read.c
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1994-08-01
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546 lines
#ifndef lint
static char rcsid[] = "$Header: /usr/people/sam/tiff/libtiff/RCS/tif_read.c,v 1.51 92/10/26 17:08:25 sam Rel $";
#endif
/*
* Copyright (c) 1988, 1989, 1990, 1991, 1992 Sam Leffler
* Copyright (c) 1991, 1992 Silicon Graphics, Inc.
*
* Permission to use, copy, modify, distribute, and sell this software and
* its documentation for any purpose is hereby granted without fee, provided
* that (i) the above copyright notices and this permission notice appear in
* all copies of the software and related documentation, and (ii) the names of
* Sam Leffler and Silicon Graphics may not be used in any advertising or
* publicity relating to the software without the specific, prior written
* permission of Sam Leffler and Silicon Graphics.
*
* THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
* EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
* WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
*
* IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
* ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
* OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
* WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
* LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
* OF THIS SOFTWARE.
*/
/*
* TIFF Library.
* Scanline-oriented Read Support
*/
#include "tiffiop.h"
#if USE_PROTOTYPES
static int TIFFFillStrip(TIFF *, u_int);
static int TIFFFillTile(TIFF *, u_int);
static int TIFFStartStrip(TIFF *, u_int);
static int TIFFStartTile(TIFF *, u_int);
static int TIFFCheckRead(TIFF *, int);
#else
static int TIFFFillStrip();
static int TIFFFillTile();
static int TIFFStartStrip();
static int TIFFStartTile();
static int TIFFCheckRead();
#endif
/*
* Seek to a random row+sample in a file.
*/
static int
DECLARE3(TIFFSeek, TIFF*, tif, u_int, row, u_int, sample)
{
register TIFFDirectory *td = &tif->tif_dir;
int strip;
if (row >= td->td_imagelength) { /* out of range */
TIFFError(tif->tif_name, "%d: Row out of range, max %d",
row, td->td_imagelength);
return (0);
}
if (td->td_planarconfig == PLANARCONFIG_SEPARATE) {
if (sample >= td->td_samplesperpixel) {
TIFFError(tif->tif_name,
"%d: Sample out of range, max %d",
sample, td->td_samplesperpixel);
return (0);
}
strip = sample*td->td_stripsperimage + row/td->td_rowsperstrip;
} else
strip = row / td->td_rowsperstrip;
if (strip != tif->tif_curstrip) { /* different strip, refill */
if (!TIFFFillStrip(tif, strip))
return (0);
} else if (row < tif->tif_row) {
/*
* Moving backwards within the same strip: backup
* to the start and then decode forward (below).
*
* NB: If you're planning on lots of random access within a
* strip, it's better to just read and decode the entire
* strip, and then access the decoded data in a random fashion.
*/
if (!TIFFStartStrip(tif, strip))
return (0);
}
if (row != tif->tif_row) {
if (tif->tif_seek) {
/*
* Seek forward to the desired row.
*/
if (!(*tif->tif_seek)(tif, row - tif->tif_row))
return (0);
tif->tif_row = row;
} else {
TIFFError(tif->tif_name,
"Compression algorithm does not support random access");
return (0);
}
}
return (1);
}
int
/*VARARGS3*/
DECLARE4(TIFFReadScanline, TIFF*, tif, u_char*, buf, u_int, row, u_int, sample)
{
int e;
if (!TIFFCheckRead(tif, 0))
return (-1);
if (e = TIFFSeek(tif, row, sample)) {
/*
* Decompress desired row into user buffer.
*/
e = (*tif->tif_decoderow)
(tif, buf, tif->tif_scanlinesize, sample);
tif->tif_row++;
}
return (e ? 1 : -1);
}
/*
* Read a strip of data and decompress the specified
* amount into the user-supplied buffer.
*/
int
DECLARE4(TIFFReadEncodedStrip,
TIFF*, tif, u_int, strip, u_char*, buf, u_long, size)
{
TIFFDirectory *td = &tif->tif_dir;
u_long nrows, stripsize;
if (!TIFFCheckRead(tif, 0))
return (-1);
if (strip >= td->td_nstrips) {
TIFFError(tif->tif_name, "%d: Strip out of range, max %d",
strip, td->td_nstrips);
return (-1);
}
/*
* Calculate the strip size according to the number of
* rows in the strip (check for truncated last strip).
*/
if (strip != td->td_nstrips-1 ||
(nrows = td->td_imagelength % td->td_rowsperstrip) == 0)
nrows = td->td_rowsperstrip;
stripsize = TIFFVStripSize(tif, nrows);
if (size == (u_long)-1)
size = stripsize;
else if (size > stripsize)
size = stripsize;
return (TIFFFillStrip(tif, strip) &&
(*tif->tif_decodestrip)(tif, buf, size, strip / td->td_stripsperimage) ?
size : -1);
}
static int
DECLARE5(TIFFReadRawStrip1,
TIFF*, tif, u_int, strip, u_char*, buf, u_long, size, const char*, module)
{
TIFFDirectory *td = &tif->tif_dir;
if (!isMapped(tif)) {
if (!SeekOK(tif, td->td_stripoffset[strip])) {
TIFFError(module,
"%s: Seek error at scanline %d, strip %d",
tif->tif_name, tif->tif_row, strip);
return (-1);
}
if (!ReadOK(tif, buf, size)) {
TIFFError(module, "%s: Read error at scanline %d",
tif->tif_name, tif->tif_row);
return (-1);
}
} else {
if (td->td_stripoffset[strip] + size > tif->tif_size) {
TIFFError(module,
"%s: Seek error at scanline %d, strip %d",
tif->tif_name, tif->tif_row, strip);
return (-1);
}
memcpy(buf, tif->tif_base + td->td_stripoffset[strip], size);
}
return (size);
}
/*
* Read a strip of data from the file.
*/
int
DECLARE4(TIFFReadRawStrip,
TIFF*, tif, u_int, strip, u_char*, buf, u_long, size)
{
static const char module[] = "TIFFReadRawStrip";
TIFFDirectory *td = &tif->tif_dir;
u_long bytecount;
if (!TIFFCheckRead(tif, 0))
return (-1);
if (strip >= td->td_nstrips) {
TIFFError(tif->tif_name, "%d: Strip out of range, max %d",
strip, td->td_nstrips);
return (-1);
}
bytecount = td->td_stripbytecount[strip];
if (size != (u_int)-1 && size < bytecount)
bytecount = size;
return (TIFFReadRawStrip1(tif, strip, buf, bytecount, module));
}
/*
* Read the specified strip and setup for decoding.
* The data buffer is expanded, as necessary, to
* hold the strip's data.
*/
static
DECLARE2(TIFFFillStrip, TIFF*, tif, u_int, strip)
{
static const char module[] = "TIFFFillStrip";
TIFFDirectory *td = &tif->tif_dir;
u_long bytecount;
bytecount = td->td_stripbytecount[strip];
if (isMapped(tif) &&
(td->td_fillorder == tif->tif_fillorder || (tif->tif_flags & TIFF_NOBITREV))) {
/*
* The image is mapped into memory and we either don't
* need to flip bits or the compression routine is going
* to handle this operation itself. In this case, avoid
* copying the raw data and instead just reference the
* data from the memory mapped file image. This assumes
* that the decompression routines do not modify the
* contents of the raw data buffer (if they try to,
* the application will get a fault since the file is
* mapped read-only).
*/
if ((tif->tif_flags & TIFF_MYBUFFER) && tif->tif_rawdata)
_TIFFfree(tif->tif_rawdata);
tif->tif_flags &= ~TIFF_MYBUFFER;
if (td->td_stripoffset[strip] + bytecount > tif->tif_size) {
/*
* This error message might seem strange, but it's
* what would happen if a read were done instead.
*/
TIFFError(module, "%s: Read error on strip %d",
tif->tif_name, strip);
tif->tif_curstrip = -1; /* unknown state */
return (0);
}
tif->tif_rawdatasize = bytecount;
tif->tif_rawdata = tif->tif_base + td->td_stripoffset[strip];
} else {
/*
* Expand raw data buffer, if needed, to
* hold data strip coming from file
* (perhaps should set upper bound on
* the size of a buffer we'll use?).
*/
if (bytecount > tif->tif_rawdatasize) {
tif->tif_curstrip = -1; /* unknown state */
if ((tif->tif_flags & TIFF_MYBUFFER) == 0) {
TIFFError(module,
"%s: Data buffer too small to hold strip %d",
tif->tif_name, strip);
return (0);
}
if (!TIFFReadBufferSetup(tif, 0,
roundup(bytecount, 1024)))
return (0);
}
if (TIFFReadRawStrip1(tif, strip, (u_char *)tif->tif_rawdata,
bytecount, module) != bytecount)
return (0);
if (td->td_fillorder != tif->tif_fillorder &&
(tif->tif_flags & TIFF_NOBITREV) == 0)
TIFFReverseBits((u_char *)tif->tif_rawdata, bytecount);
}
return (TIFFStartStrip(tif, strip));
}
/*
* Tile-oriented Read Support
* Contributed by Nancy Cam (Silicon Graphics).
*/
/*
* Read and decompress a tile of data. The
* tile is selected by the (x,y,z,s) coordinates.
*/
int
DECLARE6(TIFFReadTile,
TIFF*, tif, u_char*, buf, u_long, x, u_long, y, u_long, z, u_int, s)
{
u_int tile;
if (!TIFFCheckRead(tif, 1) || !TIFFCheckTile(tif, x, y, z, s))
return (-1);
tile = TIFFComputeTile(tif, x, y, z, s);
if (tile >= tif->tif_dir.td_nstrips) {
TIFFError(tif->tif_name, "%d: Tile out of range, max %d",
tile, tif->tif_dir.td_nstrips);
return (-1);
}
return (TIFFFillTile(tif, tile) &&
(*tif->tif_decodetile)(tif, buf, tif->tif_tilesize, s) ?
tif->tif_tilesize : -1);
}
/*
* Read a tile of data and decompress the specified
* amount into the user-supplied buffer.
*/
int
DECLARE4(TIFFReadEncodedTile,
TIFF*, tif, u_int, tile, u_char*, buf, u_long, size)
{
TIFFDirectory *td = &tif->tif_dir;
u_long tilesize = tif->tif_tilesize;
if (!TIFFCheckRead(tif, 1))
return (-1);
if (tile >= td->td_nstrips) {
TIFFError(tif->tif_name, "%d: Tile out of range, max %d",
tile, td->td_nstrips);
return (-1);
}
if (size == (u_int)-1)
size = tilesize;
else if (size > tilesize )
size = tilesize;
return (TIFFFillTile(tif, tile) &&
(*tif->tif_decodetile)(tif, buf, size, tile/td->td_stripsperimage) ?
size : -1);
}
static int
DECLARE5(TIFFReadRawTile1,
TIFF*, tif, u_int, tile, u_char*, buf, u_long, size,
const char*, module)
{
TIFFDirectory *td = &tif->tif_dir;
if (!isMapped(tif)) {
if (!SeekOK(tif, td->td_stripoffset[tile])) {
TIFFError(module,
"%s: Seek error at row %d, col %d, tile %d",
tif->tif_name, tif->tif_row, tif->tif_col, tile);
return (-1);
}
if (!ReadOK(tif, buf, size)) {
TIFFError(module, "%s: Read error at row %d, col %d",
tif->tif_name, tif->tif_row, tif->tif_col);
return (-1);
}
} else {
if (td->td_stripoffset[tile] + size > tif->tif_size) {
TIFFError(module,
"%s: Seek error at row %d, col %d, tile %d",
tif->tif_name, tif->tif_row, tif->tif_col, tile);
return (-1);
}
memcpy(buf, tif->tif_base + td->td_stripoffset[tile], size);
}
return (size);
}
/*
* Read a tile of data from the file.
*/
int
DECLARE4(TIFFReadRawTile, TIFF*, tif, u_int, tile, u_char*, buf, u_long, size)
{
static const char module[] = "TIFFReadRawTile";
TIFFDirectory *td = &tif->tif_dir;
u_long bytecount;
if (!TIFFCheckRead(tif, 1))
return (-1);
if (tile >= td->td_nstrips) {
TIFFError(tif->tif_name, "%d: Tile out of range, max %d",
tile, td->td_nstrips);
return (-1);
}
bytecount = td->td_stripbytecount[tile];
if (size != (u_int)-1 && size < bytecount)
bytecount = size;
return (TIFFReadRawTile1(tif, tile, buf, bytecount, module));
}
/*
* Read the specified tile and setup for decoding.
* The data buffer is expanded, as necessary, to
* hold the tile's data.
*/
static
DECLARE2(TIFFFillTile, TIFF*, tif, u_int, tile)
{
static const char module[] = "TIFFFillTile";
TIFFDirectory *td = &tif->tif_dir;
u_long bytecount;
bytecount = td->td_stripbytecount[tile];
if (isMapped(tif) &&
(td->td_fillorder == tif->tif_fillorder || (tif->tif_flags & TIFF_NOBITREV))) {
/*
* The image is mapped into memory and we either don't
* need to flip bits or the compression routine is going
* to handle this operation itself. In this case, avoid
* copying the raw data and instead just reference the
* data from the memory mapped file image. This assumes
* that the decompression routines do not modify the
* contents of the raw data buffer (if they try to,
* the application will get a fault since the file is
* mapped read-only).
*/
if ((tif->tif_flags & TIFF_MYBUFFER) && tif->tif_rawdata)
_TIFFfree(tif->tif_rawdata);
tif->tif_flags &= ~TIFF_MYBUFFER;
if (td->td_stripoffset[tile] + bytecount > tif->tif_size) {
tif->tif_curtile = -1; /* unknown state */
return (0);
}
tif->tif_rawdatasize = bytecount;
tif->tif_rawdata = tif->tif_base + td->td_stripoffset[tile];
} else {
/*
* Expand raw data buffer, if needed, to
* hold data tile coming from file
* (perhaps should set upper bound on
* the size of a buffer we'll use?).
*/
if (bytecount > tif->tif_rawdatasize) {
tif->tif_curtile = -1; /* unknown state */
if ((tif->tif_flags & TIFF_MYBUFFER) == 0) {
TIFFError(module,
"%s: Data buffer too small to hold tile %d",
tif->tif_name, tile);
return (0);
}
if (!TIFFReadBufferSetup(tif, 0,
roundup(bytecount, 1024)))
return (0);
}
if (TIFFReadRawTile1(tif, tile, (u_char *)tif->tif_rawdata,
bytecount, module) != bytecount)
return (0);
if (td->td_fillorder != tif->tif_fillorder &&
(tif->tif_flags & TIFF_NOBITREV) == 0)
TIFFReverseBits((u_char *)tif->tif_rawdata, bytecount);
}
return (TIFFStartTile(tif, tile));
}
/*
* Setup the raw data buffer in preparation for
* reading a strip of raw data. If the buffer
* is specified as zero, then a buffer of appropriate
* size is allocated by the library. Otherwise,
* the client must guarantee that the buffer is
* large enough to hold any individual strip of
* raw data.
*/
int
DECLARE3(TIFFReadBufferSetup, TIFF*, tif, char*, bp, u_long, size)
{
static const char module[] = "TIFFReadBufferSetup";
if (tif->tif_rawdata) {
if (tif->tif_flags & TIFF_MYBUFFER)
_TIFFfree(tif->tif_rawdata);
tif->tif_rawdata = NULL;
}
if (bp) {
tif->tif_rawdatasize = size;
tif->tif_rawdata = bp;
tif->tif_flags &= ~TIFF_MYBUFFER;
} else {
tif->tif_rawdatasize = roundup(size, 1024);
tif->tif_rawdata = _TIFFmalloc(tif->tif_rawdatasize);
tif->tif_flags |= TIFF_MYBUFFER;
}
if (tif->tif_rawdata == NULL) {
TIFFError(module,
"%s: No space for data buffer at scanline %d",
tif->tif_name, tif->tif_row);
tif->tif_rawdatasize = 0;
return (0);
}
return (1);
}
/*
* Set state to appear as if a
* strip has just been read in.
*/
static int
DECLARE2(TIFFStartStrip, TIFF*, tif, u_int, strip)
{
TIFFDirectory *td = &tif->tif_dir;
tif->tif_curstrip = strip;
tif->tif_row = (strip % td->td_stripsperimage) * td->td_rowsperstrip;
tif->tif_rawcp = tif->tif_rawdata;
tif->tif_rawcc = td->td_stripbytecount[strip];
return (tif->tif_predecode == NULL || (*tif->tif_predecode)(tif));
}
/*
* Set state to appear as if a
* tile has just been read in.
*/
static int
DECLARE2(TIFFStartTile, TIFF*, tif, u_int, tile)
{
TIFFDirectory *td = &tif->tif_dir;
tif->tif_curtile = tile;
tif->tif_row =
(tile % howmany(td->td_imagewidth, td->td_tilewidth)) *
td->td_tilelength;
tif->tif_col =
(tile % howmany(td->td_imagelength, td->td_tilelength)) *
td->td_tilewidth;
tif->tif_rawcp = tif->tif_rawdata;
tif->tif_rawcc = td->td_stripbytecount[tile];
return (tif->tif_predecode == NULL || (*tif->tif_predecode)(tif));
}
static int
DECLARE2(TIFFCheckRead, TIFF*, tif, int, tiles)
{
if (tif->tif_mode == O_WRONLY) {
TIFFError(tif->tif_name, "File not open for reading");
return (0);
}
if (tiles ^ isTiled(tif)) {
TIFFError(tif->tif_name, tiles ?
"Can not read tiles from a stripped image" :
"Can not read scanlines from a tiled image");
return (0);
}
return (1);
}