webp/examples/tiffdec.c
James Zern 7c732e59f4 cwebp: centralize WebPCleanupTransparentArea()
this can be safely called whether the picture has alpha or not

Change-Id: I0047fd4c110f1072f183f3d340682502bd6623d7
2013-02-04 15:44:26 -08:00

139 lines
4.1 KiB
C

// Copyright 2012 Google Inc. All Rights Reserved.
//
// This code is licensed under the same terms as WebM:
// Software License Agreement: http://www.webmproject.org/license/software/
// Additional IP Rights Grant: http://www.webmproject.org/license/additional/
// -----------------------------------------------------------------------------
//
// TIFF decode.
#include "./tiffdec.h"
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <stdio.h>
#ifdef WEBP_HAVE_TIFF
#include <tiffio.h>
#include "webp/encode.h"
#include "./metadata.h"
static const struct {
ttag_t tag;
size_t storage_offset;
} kTIFFMetadataMap[] = {
{ TIFFTAG_ICCPROFILE, METADATA_OFFSET(iccp) },
{ TIFFTAG_XMLPACKET, METADATA_OFFSET(xmp) },
{ 0, 0 },
};
// Returns true on success. The caller must use MetadataFree() on 'metadata' in
// all cases.
static int ExtractMetadataFromTIFF(TIFF* const tif, Metadata* const metadata) {
int i;
toff_t exif_ifd_offset;
for (i = 0; kTIFFMetadataMap[i].tag != 0; ++i) {
MetadataPayload* const payload =
(MetadataPayload*)((uint8_t*)metadata +
kTIFFMetadataMap[i].storage_offset);
void* tag_data;
uint32 tag_data_len;
if (TIFFGetField(tif, kTIFFMetadataMap[i].tag, &tag_data_len, &tag_data) &&
!MetadataCopy((const char*)tag_data, tag_data_len, payload)) {
return 0;
}
}
// TODO(jzern): To extract the raw EXIF directory some parsing of it would be
// necessary to determine the overall size. In addition, value offsets in
// individual directory entries may need to be updated as, depending on the
// type, they are file based.
// Exif 2.2 Section 4.6.2 Tag Structure
// TIFF Revision 6.0 Part 1 Section 2 TIFF Structure #Image File Directory
if (TIFFGetField(tif, TIFFTAG_EXIFIFD, &exif_ifd_offset)) {
fprintf(stderr, "Warning: EXIF extraction from TIFF is unsupported.\n");
}
return 1;
}
int ReadTIFF(const char* const filename,
WebPPicture* const pic, int keep_alpha,
Metadata* const metadata) {
TIFF* const tif = TIFFOpen(filename, "r");
uint32 width, height;
uint32* raster;
int ok = 0;
tdir_t dircount;
if (tif == NULL) {
fprintf(stderr, "Error! Cannot open TIFF file '%s'\n", filename);
return 0;
}
dircount = TIFFNumberOfDirectories(tif);
if (dircount > 1) {
fprintf(stderr, "Warning: multi-directory TIFF files are not supported.\n"
"Only the first will be used, %d will be ignored.\n",
dircount - 1);
}
if (!(TIFFGetField(tif, TIFFTAG_IMAGEWIDTH, &width) &&
TIFFGetField(tif, TIFFTAG_IMAGELENGTH, &height))) {
fprintf(stderr, "Error! Cannot retrieve TIFF image dimensions.\n");
return 0;
}
raster = (uint32*)_TIFFmalloc(width * height * sizeof(*raster));
if (raster != NULL) {
if (TIFFReadRGBAImageOriented(tif, width, height, raster,
ORIENTATION_TOPLEFT, 1)) {
const int stride = width * sizeof(*raster);
pic->width = width;
pic->height = height;
// TIFF data is ABGR
#ifdef __BIG_ENDIAN__
TIFFSwabArrayOfLong(raster, width * height);
#endif
ok = keep_alpha
? WebPPictureImportRGBA(pic, (const uint8_t*)raster, stride)
: WebPPictureImportRGBX(pic, (const uint8_t*)raster, stride);
}
_TIFFfree(raster);
} else {
fprintf(stderr, "Error allocating TIFF RGBA memory!\n");
}
if (ok) {
if (metadata != NULL) {
ok = ExtractMetadataFromTIFF(tif, metadata);
if (!ok) {
fprintf(stderr, "Error extracting TIFF metadata!\n");
MetadataFree(metadata);
WebPPictureFree(pic);
}
}
}
TIFFClose(tif);
return ok;
}
#else // !WEBP_HAVE_TIFF
int ReadTIFF(const char* const filename,
struct WebPPicture* const pic, int keep_alpha,
struct Metadata* const metadata) {
(void)filename;
(void)pic;
(void)keep_alpha;
(void)metadata;
fprintf(stderr, "TIFF support not compiled. Please install the libtiff "
"development package before building.\n");
return 0;
}
#endif // WEBP_HAVE_TIFF
// -----------------------------------------------------------------------------