/* $Id: tif_tile.c,v 1.12.2.1 2010-06-08 18:50:43 bfriesen 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.

 *

 * Tiled 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, because sizeof(size_t)

	 * may be larger than sizeof(uint32) on 64-bit architectures.

	 */

	uint32	bytes = summand1 + summand2;

	if (bytes - summand1 != summand2) {

		TIFFErrorExt(tif->tif_clientdata, 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) {

		TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "Integer overflow in %s", where);

		bytes = 0;

	}

	return (bytes);

}

/*

 * Compute which tile an (x,y,z,s) value is in.

 */

ttile_t

TIFFComputeTile(TIFF* tif, uint32 x, uint32 y, uint32 z, tsample_t s)

{

	TIFFDirectory *td = &tif->tif_dir;

	uint32 dx = td->td_tilewidth;

	uint32 dy = td->td_tilelength;

	uint32 dz = td->td_tiledepth;

	ttile_t tile = 1;

	if (td->td_imagedepth == 1)

		z = 0;

	if (dx == (uint32) -1)

		dx = td->td_imagewidth;

	if (dy == (uint32) -1)

		dy = td->td_imagelength;

	if (dz == (uint32) -1)

		dz = td->td_imagedepth;

	if (dx != 0 && dy != 0 && dz != 0) {

		uint32 xpt = TIFFhowmany(td->td_imagewidth, dx); 

		uint32 ypt = TIFFhowmany(td->td_imagelength, dy); 

		uint32 zpt = TIFFhowmany(td->td_imagedepth, dz); 

		if (td->td_planarconfig == PLANARCONFIG_SEPARATE) 

			tile = (xpt*ypt*zpt)*s +

			     (xpt*ypt)*(z/dz) +

			     xpt*(y/dy) +

			     x/dx;

		else

			tile = (xpt*ypt)*(z/dz) + xpt*(y/dy) + x/dx;

	}

	return (tile);

}

/*

 * Check an (x,y,z,s) coordinate

 * against the image bounds.

 */

int

TIFFCheckTile(TIFF* tif, uint32 x, uint32 y, uint32 z, tsample_t s)

{

	TIFFDirectory *td = &tif->tif_dir;

	if (x >= td->td_imagewidth) {

		TIFFErrorExt(tif->tif_clientdata, tif->tif_name,

			     "%lu: Col out of range, max %lu",

			     (unsigned long) x,

			     (unsigned long) (td->td_imagewidth - 1));

		return (0);

	}

	if (y >= td->td_imagelength) {

		TIFFErrorExt(tif->tif_clientdata, tif->tif_name,

			     "%lu: Row out of range, max %lu",

			     (unsigned long) y,

			     (unsigned long) (td->td_imagelength - 1));

		return (0);

	}

	if (z >= td->td_imagedepth) {

		TIFFErrorExt(tif->tif_clientdata, tif->tif_name,

			     "%lu: Depth out of range, max %lu",

			     (unsigned long) z,

			     (unsigned long) (td->td_imagedepth - 1));

		return (0);

	}

	if (td->td_planarconfig == PLANARCONFIG_SEPARATE &&

	    s >= td->td_samplesperpixel) {

		TIFFErrorExt(tif->tif_clientdata, tif->tif_name,

			     "%lu: Sample out of range, max %lu",

			     (unsigned long) s,

			     (unsigned long) (td->td_samplesperpixel - 1));

		return (0);

	}

	return (1);

}

/*

 * Compute how many tiles are in an image.

 */

ttile_t

TIFFNumberOfTiles(TIFF* tif)

{

	TIFFDirectory *td = &tif->tif_dir;

	uint32 dx = td->td_tilewidth;

	uint32 dy = td->td_tilelength;

	uint32 dz = td->td_tiledepth;

	ttile_t ntiles;

	if (dx == (uint32) -1)

		dx = td->td_imagewidth;

	if (dy == (uint32) -1)

		dy = td->td_imagelength;

	if (dz == (uint32) -1)

		dz = td->td_imagedepth;

	ntiles = (dx == 0 || dy == 0 || dz == 0) ? 0 :

	    multiply(tif, multiply(tif, TIFFhowmany(td->td_imagewidth, dx),

				   TIFFhowmany(td->td_imagelength, dy),

				   "TIFFNumberOfTiles"),

		     TIFFhowmany(td->td_imagedepth, dz), "TIFFNumberOfTiles");

	if (td->td_planarconfig == PLANARCONFIG_SEPARATE)

		ntiles = multiply(tif, ntiles, td->td_samplesperpixel,

				  "TIFFNumberOfTiles");

	return (ntiles);

}

/*

 * Compute the # bytes in each row of a tile.

 */

tsize_t

TIFFTileRowSize(TIFF* tif)

{

	TIFFDirectory *td = &tif->tif_dir;

	uint32 rowsize;

	if (td->td_tilelength == 0 || td->td_tilewidth == 0)

		return ((tsize_t) 0);

	rowsize = multiply(tif, td->td_bitspersample, td->td_tilewidth,

			   "TIFFTileRowSize");

	if (td->td_planarconfig == PLANARCONFIG_CONTIG)

		rowsize = multiply(tif, rowsize, td->td_samplesperpixel,

				   "TIFFTileRowSize");

	return ((tsize_t) TIFFhowmany8(rowsize));

}

/*

 * Compute the # bytes in a variable length, row-aligned tile.

 */

tsize_t

TIFFVTileSize(TIFF* tif, uint32 nrows)

{

	TIFFDirectory *td = &tif->tif_dir;

	uint32 tilesize;

	if (td->td_tilelength == 0 || td->td_tilewidth == 0 ||

	    td->td_tiledepth == 0)

		return ((tsize_t) 0);

	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.

		 */

		uint32 w =

		    TIFFroundup(td->td_tilewidth, td->td_ycbcrsubsampling[0]);

		uint32 rowsize =

		    TIFFhowmany8(multiply(tif, w, td->td_bitspersample,

					  "TIFFVTileSize"));

		uint32 samplingarea =

		    td->td_ycbcrsubsampling[0]*td->td_ycbcrsubsampling[1];

		if (samplingarea == 0) {

			TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "Invalid YCbCr subsampling");

			return 0;

		}

		nrows = TIFFroundup(nrows, td->td_ycbcrsubsampling[1]);

		/* NB: don't need TIFFhowmany here 'cuz everything is rounded */

		tilesize = multiply(tif, nrows, rowsize, "TIFFVTileSize");

		/* a zero anywhere in here means overflow, must return zero */

		if (tilesize > 0) {

			uint32 extra =

			    multiply(tif, 2, tilesize / samplingarea,

				     "TIFFVTileSize");

			if (extra > 0)

				tilesize = summarize(tif, tilesize, extra,

						     "TIFFVTileSize");

			else

				tilesize = 0;

		}

	} else

		tilesize = multiply(tif, nrows, TIFFTileRowSize(tif),

				    "TIFFVTileSize");

	tilesize = multiply(tif, tilesize, td->td_tiledepth, "TIFFVTileSize");

	/* Because tsize_t is signed, we might have conversion overflow */

	if (((tsize_t) tilesize) < 0) {

		TIFFErrorExt(tif->tif_clientdata, tif->tif_name, "Integer overflow in %s", "TIFFVTileSize");

		tilesize = 0;

	}

	return (tsize_t) tilesize;

}

/*

 * Compute the # bytes in a row-aligned tile.

 */

tsize_t

TIFFTileSize(TIFF* tif)

{

	return (TIFFVTileSize(tif, tif->tif_dir.td_tilelength));

}

/*

 * Compute a default tile size based on the image

 * characteristics and a requested value.  If a

 * request is <1 then we choose a size according

 * to certain heuristics.

 */

void

TIFFDefaultTileSize(TIFF* tif, uint32* tw, uint32* th)

{

	(*tif->tif_deftilesize)(tif, tw, th);

}

void

_TIFFDefaultTileSize(TIFF* tif, uint32* tw, uint32* th)

{

	(void) tif;

	if (*(int32*) tw < 1)

		*tw = 256;

	if (*(int32*) th < 1)

		*th = 256;

	/* roundup to a multiple of 16 per the spec */

	if (*tw & 0xf)

		*tw = TIFFroundup(*tw, 16);

	if (*th & 0xf)

		*th = TIFFroundup(*th, 16);

}

/* vim: set ts=8 sts=8 sw=8 noet: */

/*

 * Local Variables:

 * mode: c

 * c-basic-offset: 8

 * fill-column: 78

 * End:

 */