/* $Header: /cvs/maptools/cvsroot/libtiff/contrib/pds/tif_imageiter.c,v 1.2 2004/05/19 17:14:45 dron Exp $ *//* * Copyright (c) 1991-1996 Sam Leffler * Copyright (c) 1991-1996 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 * * Written by Conrad J. Poelman, PL/WSAT, Kirtland AFB, NM on 26 Mar 96. * * This file contains code to allow a calling program to "iterate" over each * pixels in an image as it is read from the file. The iterator takes care of * reading strips versus (possibly clipped) tiles, decoding the information * according to the decoding method, and so on, so that calling program can * ignore those details. The calling program does, however, need to be * conscious of the type of the pixel data that it is receiving. * * For reasons of efficiency, the callback function actually gets called for  * "blocks" of pixels rather than for individual pixels. The format of the * callback arguments is given below. * * This code was taken from TIFFReadRGBAImage() in tif_getimage.c of the original * TIFF distribution, and simplified and generalized to provide this general * iteration capability. Those routines could certainly be re-implemented in terms * of a TIFFImageIter if desired. * */#include "tiffiop.h"#include "tif_imageiter.h"#include <assert.h>#include <stdio.h>static	int gtTileContig(TIFFImageIter*, void *udata, uint32, uint32);static	int gtTileSeparate(TIFFImageIter*, void *udata, uint32, uint32);static	int gtStripContig(TIFFImageIter*, void *udata, uint32, uint32);static	int gtStripSeparate(TIFFImageIter*, void *udata, uint32, uint32);static	const char photoTag[] = "PhotometricInterpretation";static intisCCITTCompression(TIFF* tif){    uint16 compress;    TIFFGetField(tif, TIFFTAG_COMPRESSION, &compress);    return (compress == COMPRESSION_CCITTFAX3 ||	    compress == COMPRESSION_CCITTFAX4 ||	    compress == COMPRESSION_CCITTRLE ||	    compress == COMPRESSION_CCITTRLEW);}intTIFFImageIterBegin(TIFFImageIter* img, TIFF* tif, int stop, char emsg[1024]){    uint16* sampleinfo;    uint16 extrasamples;    uint16 planarconfig;    int colorchannels;    img->tif = tif;    img->stoponerr = stop;    TIFFGetFieldDefaulted(tif, TIFFTAG_BITSPERSAMPLE, &img->bitspersample);    img->alpha = 0;    TIFFGetFieldDefaulted(tif, TIFFTAG_SAMPLESPERPIXEL, &img->samplesperpixel);    TIFFGetFieldDefaulted(tif, TIFFTAG_EXTRASAMPLES,	&extrasamples, &sampleinfo);    if (extrasamples == 1)	switch (sampleinfo[0]) {	case EXTRASAMPLE_ASSOCALPHA:	/* data is pre-multiplied */	case EXTRASAMPLE_UNASSALPHA:	/* data is not pre-multiplied */	    img->alpha = sampleinfo[0];	    break;	}    colorchannels = img->samplesperpixel - extrasamples;    TIFFGetFieldDefaulted(tif, TIFFTAG_PLANARCONFIG, &planarconfig);    if (!TIFFGetField(tif, TIFFTAG_PHOTOMETRIC, &img->photometric)) {	switch (colorchannels) {	case 1:	    if (isCCITTCompression(tif))		img->photometric = PHOTOMETRIC_MINISWHITE;	    else		img->photometric = PHOTOMETRIC_MINISBLACK;	    break;	case 3:	    img->photometric = PHOTOMETRIC_RGB;	    break;	default:	    sprintf(emsg, "Missing needed %s tag", photoTag);	    return (0);	}    }    switch (img->photometric) {    case PHOTOMETRIC_PALETTE:	if (!TIFFGetField(tif, TIFFTAG_COLORMAP,	    &img->redcmap, &img->greencmap, &img->bluecmap)) {	    TIFFError(TIFFFileName(tif), "Missing required \"Colormap\" tag");	    return (0);	}	/* fall thru... */    case PHOTOMETRIC_MINISWHITE:    case PHOTOMETRIC_MINISBLACK:/* This should work now so skip the check - BSR	if (planarconfig == PLANARCONFIG_CONTIG && img->samplesperpixel != 1) {	    sprintf(emsg,		"Sorry, can not handle contiguous data with %s=%d, and %s=%d",		photoTag, img->photometric,		"Samples/pixel", img->samplesperpixel);	    return (0);	} */	break;    case PHOTOMETRIC_YCBCR:	if (planarconfig != PLANARCONFIG_CONTIG) {	    sprintf(emsg, "Sorry, can not handle YCbCr images with %s=%d",		"Planarconfiguration", planarconfig);	    return (0);	}	/* It would probably be nice to have a reality check here. */	{ uint16 compress;	  TIFFGetField(tif, TIFFTAG_COMPRESSION, &compress);	  if (compress == COMPRESSION_JPEG && planarconfig == PLANARCONFIG_CONTIG) {	    /* can rely on libjpeg to convert to RGB */	    /* XXX should restore current state on exit */	    TIFFSetField(tif, TIFFTAG_JPEGCOLORMODE, JPEGCOLORMODE_RGB);	    img->photometric = PHOTOMETRIC_RGB;	  }	}	break;    case PHOTOMETRIC_RGB: 	if (colorchannels < 3) {	    sprintf(emsg, "Sorry, can not handle RGB image with %s=%d",		"Color channels", colorchannels);	    return (0);	}	break;    case PHOTOMETRIC_SEPARATED: {	uint16 inkset;	TIFFGetFieldDefaulted(tif, TIFFTAG_INKSET, &inkset);	if (inkset != INKSET_CMYK) {	    sprintf(emsg, "Sorry, can not handle separated image with %s=%d",		"InkSet", inkset);	    return (0);	}	if (img->samplesperpixel != 4) {	    sprintf(emsg, "Sorry, can not handle separated image with %s=%d",		"Samples/pixel", img->samplesperpixel);	    return (0);	}	break;    }    default:	sprintf(emsg, "Sorry, can not handle image with %s=%d",	    photoTag, img->photometric);	return (0);    }    TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &img->width);    TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &img->height);    TIFFGetFieldDefaulted(tif, TIFFTAG_ORIENTATION, &img->orientation);    switch (img->orientation) {    case ORIENTATION_BOTRIGHT:    case ORIENTATION_RIGHTBOT:	/* XXX */    case ORIENTATION_LEFTBOT:	/* XXX */	TIFFWarning(TIFFFileName(tif), "using bottom-left orientation");	img->orientation = ORIENTATION_BOTLEFT;	/* fall thru... */    case ORIENTATION_BOTLEFT:	break;    case ORIENTATION_TOPRIGHT:    case ORIENTATION_RIGHTTOP:	/* XXX */    case ORIENTATION_LEFTTOP:	/* XXX */    default:	TIFFWarning(TIFFFileName(tif), "using top-left orientation");	img->orientation = ORIENTATION_TOPLEFT;	/* fall thru... */    case ORIENTATION_TOPLEFT:	break;    }    img->isContig =	!(planarconfig == PLANARCONFIG_SEPARATE && colorchannels > 1);    if (img->isContig) {	img->get = TIFFIsTiled(tif) ? gtTileContig : gtStripContig;    } else {	img->get = TIFFIsTiled(tif) ? gtTileSeparate : gtStripSeparate;    }    return (1);}intTIFFImageIterGet(TIFFImageIter* img, void *udata, uint32 w, uint32 h){    if (img->get == NULL) {	TIFFError(TIFFFileName(img->tif), "No \"get\" routine setup");	return (0);    }    if (img->callback.any == NULL) {	TIFFError(TIFFFileName(img->tif),	    "No \"put\" routine setupl; probably can not handle image format");	return (0);    }    return (*img->get)(img, udata, w, h);}TIFFImageIterEnd(TIFFImageIter* img){    /* Nothing to free... ? */}/* * Read the specified image into an ABGR-format raster. */intTIFFReadImageIter(TIFF* tif,    uint32 rwidth, uint32 rheight, uint8* raster, int stop){    char emsg[1024];    TIFFImageIter img;    int ok;    if (TIFFImageIterBegin(&img, tif, stop, emsg)) {	/* XXX verify rwidth and rheight against width and height */	ok = TIFFImageIterGet(&img, raster, rwidth, img.height);	TIFFImageIterEnd(&img);    } else {	TIFFError(TIFFFileName(tif), emsg);	ok = 0;    }    return (ok);}/* * Get an tile-organized image that has *	PlanarConfiguration contiguous if SamplesPerPixel > 1 * or *	SamplesPerPixel == 1 */	static intgtTileContig(TIFFImageIter* img, void *udata, uint32 w, uint32 h)