src/tiff/tif_strip.c

/* $Header$ */

/*
 * 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"

/*
 * 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,
			    "%u: Sample out of range, max %u",
			    sample, 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 ?
	     (td->td_imagelength != 0 ? 1 : 0) :
	     TIFFhowmany(td->td_imagelength, td->td_rowsperstrip));
	if (td->td_planarconfig == PLANARCONFIG_SEPARATE)
		nstrips *= td->td_samplesperpixel;
	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;
#ifdef YCBCR_SUPPORT
	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.
		 */
		tsize_t w =
		    TIFFroundup(td->td_imagewidth, td->td_ycbcrsubsampling[0]);
		tsize_t scanline = TIFFhowmany(w*td->td_bitspersample, 8);
		tsize_t samplingarea =
		    td->td_ycbcrsubsampling[0]*td->td_ycbcrsubsampling[1];
		nrows = TIFFroundup(nrows, td->td_ycbcrsubsampling[1]);
		/* NB: don't need TIFFhowmany here 'cuz everything is rounded */
		return ((tsize_t)
		    (nrows*scanline + 2*(nrows*scanline / samplingarea)));
	} else
#endif
		return ((tsize_t)(nrows * TIFFScanlineSize(tif)));
}

/*
 * 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 = td->td_bitspersample * td->td_imagewidth;
	if (td->td_planarconfig == PLANARCONFIG_CONTIG)
		scanline *= td->td_samplesperpixel;
	return ((tsize_t) TIFFhowmany(scanline, 8));
}

/*
 * 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 = td->td_bitspersample * td->td_imagewidth;
	if (td->td_planarconfig == PLANARCONFIG_CONTIG) {
		scanline *= td->td_samplesperpixel;
		return ((tsize_t) TIFFhowmany(scanline, 8));
	} else
		return ((tsize_t)
		    TIFFhowmany(scanline, 8)*td->td_samplesperpixel);
}
Commit	Line	Data
	1	/* $Header$ */
	2
	3	/*
	4	* Copyright (c) 1991-1997 Sam Leffler
	5	* Copyright (c) 1991-1997 Silicon Graphics, Inc.
	6	*
	7	* Permission to use, copy, modify, distribute, and sell this software and
	8	* its documentation for any purpose is hereby granted without fee, provided
	9	* that (i) the above copyright notices and this permission notice appear in
	10	* all copies of the software and related documentation, and (ii) the names of
	11	* Sam Leffler and Silicon Graphics may not be used in any advertising or
	12	* publicity relating to the software without the specific, prior written
	13	* permission of Sam Leffler and Silicon Graphics.
	14	*
	15	* THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND,
	16	* EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY
	17	* WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
	18	*
	19	* IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR
	20	* ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND,
	21	* OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
	22	* WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF
	23	* LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
	24	* OF THIS SOFTWARE.
	25	*/
	26
	27	/*
	28	* TIFF Library.
	29	*
	30	* Strip-organized Image Support Routines.
	31	*/
	32	#include "tiffiop.h"
	33
	34	/*
	35	* Compute which strip a (row,sample) value is in.
	36	*/
	37	tstrip_t
	38	TIFFComputeStrip(TIFF* tif, uint32 row, tsample_t sample)
	39	{
	40	TIFFDirectory *td = &tif->tif_dir;
	41	tstrip_t strip;
	42
	43	strip = row / td->td_rowsperstrip;
	44	if (td->td_planarconfig == PLANARCONFIG_SEPARATE) {
	45	if (sample >= td->td_samplesperpixel) {
	46	TIFFError(tif->tif_name,
	47	"%u: Sample out of range, max %u",
	48	sample, td->td_samplesperpixel);
	49	return ((tstrip_t) 0);
	50	}
	51	strip += sample*td->td_stripsperimage;
	52	}
	53	return (strip);
	54	}
	55
	56	/*
	57	* Compute how many strips are in an image.
	58	*/
	59	tstrip_t
	60	TIFFNumberOfStrips(TIFF* tif)
	61	{
	62	TIFFDirectory *td = &tif->tif_dir;
	63	tstrip_t nstrips;
	64
	65	nstrips = (td->td_rowsperstrip == (uint32) -1 ?
	66	(td->td_imagelength != 0 ? 1 : 0) :
	67	TIFFhowmany(td->td_imagelength, td->td_rowsperstrip));
	68	if (td->td_planarconfig == PLANARCONFIG_SEPARATE)
	69	nstrips *= td->td_samplesperpixel;
	70	return (nstrips);
	71	}
	72
	73	/*
	74	* Compute the # bytes in a variable height, row-aligned strip.
	75	*/
	76	tsize_t
	77	TIFFVStripSize(TIFF* tif, uint32 nrows)
	78	{
	79	TIFFDirectory *td = &tif->tif_dir;
	80
	81	if (nrows == (uint32) -1)
	82	nrows = td->td_imagelength;
	83	#ifdef YCBCR_SUPPORT
	84	if (td->td_planarconfig == PLANARCONFIG_CONTIG &&
	85	td->td_photometric == PHOTOMETRIC_YCBCR &&
	86	!isUpSampled(tif)) {
	87	/*
	88	* Packed YCbCr data contain one Cb+Cr for every
	89	* HorizontalSampling*VerticalSampling Y values.
	90	* Must also roundup width and height when calculating
	91	* since images that are not a multiple of the
	92	* horizontal/vertical subsampling area include
	93	* YCbCr data for the extended image.
	94	*/
	95	tsize_t w =
	96	TIFFroundup(td->td_imagewidth, td->td_ycbcrsubsampling[0]);
	97	tsize_t scanline = TIFFhowmany(w*td->td_bitspersample, 8);
	98	tsize_t samplingarea =
	99	td->td_ycbcrsubsampling[0]*td->td_ycbcrsubsampling[1];
	100	nrows = TIFFroundup(nrows, td->td_ycbcrsubsampling[1]);
	101	/* NB: don't need TIFFhowmany here 'cuz everything is rounded */
	102	return ((tsize_t)
	103	(nrowsscanline + 2(nrows*scanline / samplingarea)));
	104	} else
	105	#endif
	106	return ((tsize_t)(nrows * TIFFScanlineSize(tif)));
	107	}
	108
	109	/*
	110	* Compute the # bytes in a (row-aligned) strip.
	111	*
	112	* Note that if RowsPerStrip is larger than the
	113	* recorded ImageLength, then the strip size is
	114	* truncated to reflect the actual space required
	115	* to hold the strip.
	116	*/
	117	tsize_t
	118	TIFFStripSize(TIFF* tif)
	119	{
	120	TIFFDirectory* td = &tif->tif_dir;
	121	uint32 rps = td->td_rowsperstrip;
	122	if (rps > td->td_imagelength)
	123	rps = td->td_imagelength;
	124	return (TIFFVStripSize(tif, rps));
	125	}
	126
	127	/*
	128	* Compute a default strip size based on the image
	129	* characteristics and a requested value. If the
	130	* request is <1 then we choose a strip size according
	131	* to certain heuristics.
	132	*/
	133	uint32
	134	TIFFDefaultStripSize(TIFF* tif, uint32 request)
	135	{
	136	return (*tif->tif_defstripsize)(tif, request);
	137	}
	138
	139	uint32
	140	_TIFFDefaultStripSize(TIFF* tif, uint32 s)
	141	{
	142	if ((int32) s < 1) {
	143	/*
	144	* If RowsPerStrip is unspecified, try to break the
	145	* image up into strips that are approximately 8Kbytes.
	146	*/
	147	tsize_t scanline = TIFFScanlineSize(tif);
	148	s = (uint32)(8*1024) / (scanline == 0 ? 1 : scanline);
	149	if (s == 0) /* very wide images */
	150	s = 1;
	151	}
	152	return (s);
	153	}
	154
	155	/*
	156	* Return the number of bytes to read/write in a call to
	157	* one of the scanline-oriented i/o routines. Note that
	158	* this number may be 1/samples-per-pixel if data is
	159	* stored as separate planes.
	160	*/
	161	tsize_t
	162	TIFFScanlineSize(TIFF* tif)
	163	{
	164	TIFFDirectory *td = &tif->tif_dir;
	165	tsize_t scanline;
	166
	167	scanline = td->td_bitspersample * td->td_imagewidth;
	168	if (td->td_planarconfig == PLANARCONFIG_CONTIG)
	169	scanline *= td->td_samplesperpixel;
	170	return ((tsize_t) TIFFhowmany(scanline, 8));
	171	}
	172
	173	/*
	174	* Return the number of bytes required to store a complete
	175	* decoded and packed raster scanline (as opposed to the
	176	* I/O size returned by TIFFScanlineSize which may be less
	177	* if data is store as separate planes).
	178	*/
	179	tsize_t
	180	TIFFRasterScanlineSize(TIFF* tif)
	181	{
	182	TIFFDirectory *td = &tif->tif_dir;
	183	tsize_t scanline;
	184
	185	scanline = td->td_bitspersample * td->td_imagewidth;
	186	if (td->td_planarconfig == PLANARCONFIG_CONTIG) {
	187	scanline *= td->td_samplesperpixel;
	188	return ((tsize_t) TIFFhowmany(scanline, 8));
	189	} else
	190	return ((tsize_t)
	191	TIFFhowmany(scanline, 8)*td->td_samplesperpixel);
	192	}