+++ /dev/null
-/* $Id: tif_strip.c,v 1.1 2005/06/17 13:54:52 vp153 Exp $ */
-
-/*
- * Copyright (c) 1991-1997 Sam Leffler
- * Copyright (c) 1991-1997 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.
- *
- * Strip-organized Image Support Routines.
- */
-#include "tiffiop.h"
-
-static uint32
-summarize(TIFF* tif, size_t summand1, size_t summand2, const char* where)
-{
- /*
- * XXX: We are using casting to uint32 here, bacause sizeof(size_t)
- * may be larger than sizeof(uint32) on 64-bit architectures.
- */
- uint32 bytes = summand1 + summand2;
-
- if (bytes - summand1 != summand2) {
- TIFFError(tif->tif_name, "Integer overflow in %s", where);
- bytes = 0;
- }
-
- return (bytes);
-}
-
-static uint32
-multiply(TIFF* tif, size_t nmemb, size_t elem_size, const char* where)
-{
- uint32 bytes = nmemb * elem_size;
-
- if (elem_size && bytes / elem_size != nmemb) {
- TIFFError(tif->tif_name, "Integer overflow in %s", where);
- bytes = 0;
- }
-
- return (bytes);
-}
-
-/*
- * Compute which strip a (row,sample) value is in.
- */
-tstrip_t
-TIFFComputeStrip(TIFF* tif, uint32 row, tsample_t sample)
-{
- TIFFDirectory *td = &tif->tif_dir;
- tstrip_t strip;
-
- strip = row / td->td_rowsperstrip;
- if (td->td_planarconfig == PLANARCONFIG_SEPARATE) {
- if (sample >= td->td_samplesperpixel) {
- TIFFError(tif->tif_name,
- "%lu: Sample out of range, max %lu",
- (unsigned long) sample, (unsigned long) td->td_samplesperpixel);
- return ((tstrip_t) 0);
- }
- strip += sample*td->td_stripsperimage;
- }
- return (strip);
-}
-
-/*
- * Compute how many strips are in an image.
- */
-tstrip_t
-TIFFNumberOfStrips(TIFF* tif)
-{
- TIFFDirectory *td = &tif->tif_dir;
- tstrip_t nstrips;
-
- nstrips = (td->td_rowsperstrip == (uint32) -1 ? 1 :
- TIFFhowmany(td->td_imagelength, td->td_rowsperstrip));
- if (td->td_planarconfig == PLANARCONFIG_SEPARATE)
- nstrips = multiply(tif, nstrips, td->td_samplesperpixel,
- "TIFFNumberOfStrips");
- return (nstrips);
-}
-
-/*
- * Compute the # bytes in a variable height, row-aligned strip.
- */
-tsize_t
-TIFFVStripSize(TIFF* tif, uint32 nrows)
-{
- TIFFDirectory *td = &tif->tif_dir;
-
- if (nrows == (uint32) -1)
- nrows = td->td_imagelength;
- if (td->td_planarconfig == PLANARCONFIG_CONTIG &&
- td->td_photometric == PHOTOMETRIC_YCBCR &&
- !isUpSampled(tif)) {
- /*
- * Packed YCbCr data contain one Cb+Cr for every
- * HorizontalSampling*VerticalSampling Y values.
- * Must also roundup width and height when calculating
- * since images that are not a multiple of the
- * horizontal/vertical subsampling area include
- * YCbCr data for the extended image.
- */
- uint16 ycbcrsubsampling[2];
- tsize_t w, scanline, samplingarea;
-
- TIFFGetField( tif, TIFFTAG_YCBCRSUBSAMPLING,
- ycbcrsubsampling + 0,
- ycbcrsubsampling + 1 );
-
- samplingarea = ycbcrsubsampling[0]*ycbcrsubsampling[1];
- if (samplingarea == 0) {
- TIFFError(tif->tif_name, "Invalid YCbCr subsampling");
- return 0;
- }
-
- w = TIFFroundup(td->td_imagewidth, ycbcrsubsampling[0]);
- scanline = TIFFhowmany8(multiply(tif, w, td->td_bitspersample,
- "TIFFVStripSize"));
- nrows = TIFFroundup(nrows, ycbcrsubsampling[1]);
- /* NB: don't need TIFFhowmany here 'cuz everything is rounded */
- scanline = multiply(tif, nrows, scanline, "TIFFVStripSize");
- return ((tsize_t)
- summarize(tif, scanline,
- multiply(tif, 2, scanline / samplingarea,
- "TIFFVStripSize"), "TIFFVStripSize"));
- } else
- return ((tsize_t) multiply(tif, nrows, TIFFScanlineSize(tif),
- "TIFFVStripSize"));
-}
-
-
-/*
- * Compute the # bytes in a raw strip.
- */
-tsize_t
-TIFFRawStripSize(TIFF* tif, tstrip_t strip)
-{
- TIFFDirectory* td = &tif->tif_dir;
- tsize_t bytecount = td->td_stripbytecount[strip];
-
- if (bytecount <= 0) {
- TIFFError(tif->tif_name,
- "%lu: Invalid strip byte count, strip %lu",
- (unsigned long) bytecount, (unsigned long) strip);
- bytecount = (tsize_t) -1;
- }
-
- return bytecount;
-}
-
-/*
- * Compute the # bytes in a (row-aligned) strip.
- *
- * Note that if RowsPerStrip is larger than the
- * recorded ImageLength, then the strip size is
- * truncated to reflect the actual space required
- * to hold the strip.
- */
-tsize_t
-TIFFStripSize(TIFF* tif)
-{
- TIFFDirectory* td = &tif->tif_dir;
- uint32 rps = td->td_rowsperstrip;
- if (rps > td->td_imagelength)
- rps = td->td_imagelength;
- return (TIFFVStripSize(tif, rps));
-}
-
-/*
- * Compute a default strip size based on the image
- * characteristics and a requested value. If the
- * request is <1 then we choose a strip size according
- * to certain heuristics.
- */
-uint32
-TIFFDefaultStripSize(TIFF* tif, uint32 request)
-{
- return (*tif->tif_defstripsize)(tif, request);
-}
-
-uint32
-_TIFFDefaultStripSize(TIFF* tif, uint32 s)
-{
- if ((int32) s < 1) {
- /*
- * If RowsPerStrip is unspecified, try to break the
- * image up into strips that are approximately 8Kbytes.
- */
- tsize_t scanline = TIFFScanlineSize(tif);
- s = (uint32)(8*1024) / (scanline == 0 ? 1 : scanline);
- if (s == 0) /* very wide images */
- s = 1;
- }
- return (s);
-}
-
-/*
- * Return the number of bytes to read/write in a call to
- * one of the scanline-oriented i/o routines. Note that
- * this number may be 1/samples-per-pixel if data is
- * stored as separate planes.
- */
-tsize_t
-TIFFScanlineSize(TIFF* tif)
-{
- TIFFDirectory *td = &tif->tif_dir;
- tsize_t scanline;
-
- scanline = multiply (tif, td->td_bitspersample, td->td_imagewidth,
- "TIFFScanlineSize");
- if (td->td_planarconfig == PLANARCONFIG_CONTIG)
- scanline = multiply (tif, scanline, td->td_samplesperpixel,
- "TIFFScanlineSize");
- return ((tsize_t) TIFFhowmany8(scanline));
-}
-
-/*
- * Return the number of bytes required to store a complete
- * decoded and packed raster scanline (as opposed to the
- * I/O size returned by TIFFScanlineSize which may be less
- * if data is store as separate planes).
- */
-tsize_t
-TIFFRasterScanlineSize(TIFF* tif)
-{
- TIFFDirectory *td = &tif->tif_dir;
- tsize_t scanline;
-
- scanline = multiply (tif, td->td_bitspersample, td->td_imagewidth,
- "TIFFRasterScanlineSize");
- if (td->td_planarconfig == PLANARCONFIG_CONTIG) {
- scanline = multiply (tif, scanline, td->td_samplesperpixel,
- "TIFFRasterScanlineSize");
- return ((tsize_t) TIFFhowmany8(scanline));
- } else
- return ((tsize_t) multiply (tif, TIFFhowmany8(scanline),
- td->td_samplesperpixel,
- "TIFFRasterScanlineSize"));
-}
-
-/* vim: set ts=8 sts=8 sw=8 noet: */
projects / opencv / blobdiff