webp/examples/dwebp.c

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// Copyright 2010 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/
// -----------------------------------------------------------------------------
//
// Command-line tool for decoding a WebP image.
//
// Author: Skal (pascal.massimino@gmail.com)
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#ifdef WEBP_HAVE_PNG
#include <png.h>
#endif
#ifdef HAVE_WINCODEC_H
#ifdef __MINGW32__
#define INITGUID // Without this GUIDs are declared extern and fail to link
#endif
#define CINTERFACE
#define COBJMACROS
#define _WIN32_IE 0x500 // Workaround bug in shlwapi.h when compiling C++
// code with COBJMACROS.
#include <shlwapi.h>
#include <windows.h>
#include <wincodec.h>
#endif
#include "webp/decode.h"
#include "./example_util.h"
#include "./stopwatch.h"
static int verbose = 0;
#ifndef WEBP_DLL
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif
extern void* VP8GetCPUInfo; // opaque forward declaration.
#if defined(__cplusplus) || defined(c_plusplus)
} // extern "C"
#endif
#endif // WEBP_DLL
//------------------------------------------------------------------------------
// Output types
typedef enum {
PNG = 0,
PAM,
PPM,
PGM,
BMP,
TIFF,
YUV,
ALPHA_PLANE_ONLY // this is for experimenting only
} OutputFileFormat;
#ifdef HAVE_WINCODEC_H
#define IFS(fn) \
do { \
if (SUCCEEDED(hr)) { \
hr = (fn); \
if (FAILED(hr)) fprintf(stderr, #fn " failed %08lx\n", hr); \
} \
} while (0)
#ifdef __cplusplus
#define MAKE_REFGUID(x) (x)
#else
#define MAKE_REFGUID(x) &(x)
#endif
static HRESULT CreateOutputStream(const char* out_file_name, IStream** stream) {
HRESULT hr = S_OK;
IFS(SHCreateStreamOnFileA(out_file_name, STGM_WRITE | STGM_CREATE, stream));
if (FAILED(hr)) {
fprintf(stderr, "Error opening output file %s (%08lx)\n",
out_file_name, hr);
}
return hr;
}
static HRESULT WriteUsingWIC(const char* out_file_name, REFGUID container_guid,
unsigned char* rgb, int stride,
uint32_t width, uint32_t height, int has_alpha) {
HRESULT hr = S_OK;
IWICImagingFactory* factory = NULL;
IWICBitmapFrameEncode* frame = NULL;
IWICBitmapEncoder* encoder = NULL;
IStream* stream = NULL;
WICPixelFormatGUID pixel_format = has_alpha ? GUID_WICPixelFormat32bppBGRA
: GUID_WICPixelFormat24bppBGR;
IFS(CoInitialize(NULL));
IFS(CoCreateInstance(MAKE_REFGUID(CLSID_WICImagingFactory), NULL,
CLSCTX_INPROC_SERVER,
MAKE_REFGUID(IID_IWICImagingFactory),
(LPVOID*)&factory));
if (hr == REGDB_E_CLASSNOTREG) {
fprintf(stderr,
"Couldn't access Windows Imaging Component (are you running "
"Windows XP SP3 or newer?). PNG support not available. "
"Use -ppm or -pgm for available PPM and PGM formats.\n");
}
IFS(CreateOutputStream(out_file_name, &stream));
IFS(IWICImagingFactory_CreateEncoder(factory, container_guid, NULL,
&encoder));
IFS(IWICBitmapEncoder_Initialize(encoder, stream,
WICBitmapEncoderNoCache));
IFS(IWICBitmapEncoder_CreateNewFrame(encoder, &frame, NULL));
IFS(IWICBitmapFrameEncode_Initialize(frame, NULL));
IFS(IWICBitmapFrameEncode_SetSize(frame, width, height));
IFS(IWICBitmapFrameEncode_SetPixelFormat(frame, &pixel_format));
IFS(IWICBitmapFrameEncode_WritePixels(frame, height, stride,
height * stride, rgb));
IFS(IWICBitmapFrameEncode_Commit(frame));
IFS(IWICBitmapEncoder_Commit(encoder));
if (frame != NULL) IUnknown_Release(frame);
if (encoder != NULL) IUnknown_Release(encoder);
if (factory != NULL) IUnknown_Release(factory);
if (stream != NULL) IUnknown_Release(stream);
return hr;
}
static int WritePNG(const char* out_file_name,
const WebPDecBuffer* const buffer) {
const uint32_t width = buffer->width;
const uint32_t height = buffer->height;
unsigned char* const rgb = buffer->u.RGBA.rgba;
const int stride = buffer->u.RGBA.stride;
const int has_alpha = (buffer->colorspace == MODE_BGRA);
return SUCCEEDED(WriteUsingWIC(out_file_name,
MAKE_REFGUID(GUID_ContainerFormatPng),
rgb, stride, width, height, has_alpha));
}
#elif defined(WEBP_HAVE_PNG) // !HAVE_WINCODEC_H
static void PNGAPI error_function(png_structp png, png_const_charp dummy) {
(void)dummy; // remove variable-unused warning
longjmp(png_jmpbuf(png), 1);
}
static int WritePNG(FILE* out_file, const WebPDecBuffer* const buffer) {
const uint32_t width = buffer->width;
const uint32_t height = buffer->height;
unsigned char* const rgb = buffer->u.RGBA.rgba;
const int stride = buffer->u.RGBA.stride;
const int has_alpha = (buffer->colorspace == MODE_RGBA);
png_structp png;
png_infop info;
png_uint_32 y;
png = png_create_write_struct(PNG_LIBPNG_VER_STRING,
NULL, error_function, NULL);
if (png == NULL) {
return 0;
}
info = png_create_info_struct(png);
if (info == NULL) {
png_destroy_write_struct(&png, NULL);
return 0;
}
if (setjmp(png_jmpbuf(png))) {
png_destroy_write_struct(&png, &info);
return 0;
}
png_init_io(png, out_file);
png_set_IHDR(png, info, width, height, 8,
has_alpha ? PNG_COLOR_TYPE_RGBA : PNG_COLOR_TYPE_RGB,
PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT,
PNG_FILTER_TYPE_DEFAULT);
png_write_info(png, info);
for (y = 0; y < height; ++y) {
png_bytep row = rgb + y * stride;
png_write_rows(png, &row, 1);
}
png_write_end(png, info);
png_destroy_write_struct(&png, &info);
return 1;
}
#else // !HAVE_WINCODEC_H && !WEBP_HAVE_PNG
static int WritePNG(FILE* out_file, const WebPDecBuffer* const buffer) {
(void)out_file;
(void)buffer;
fprintf(stderr, "PNG support not compiled. Please install the libpng "
"development package before building.\n");
fprintf(stderr, "You can run with -ppm flag to decode in PPM format.\n");
return 0;
}
#endif
static int WritePPM(FILE* fout, const WebPDecBuffer* const buffer, int alpha) {
const uint32_t width = buffer->width;
const uint32_t height = buffer->height;
const unsigned char* const rgb = buffer->u.RGBA.rgba;
const int stride = buffer->u.RGBA.stride;
const size_t bytes_per_px = alpha ? 4 : 3;
uint32_t y;
if (alpha) {
fprintf(fout, "P7\nWIDTH %d\nHEIGHT %d\nDEPTH 4\nMAXVAL 255\n"
"TUPLTYPE RGB_ALPHA\nENDHDR\n", width, height);
} else {
fprintf(fout, "P6\n%d %d\n255\n", width, height);
}
for (y = 0; y < height; ++y) {
if (fwrite(rgb + y * stride, width, bytes_per_px, fout) != bytes_per_px) {
return 0;
}
}
return 1;
}
static void PutLE16(uint8_t* const dst, uint32_t value) {
dst[0] = (value >> 0) & 0xff;
dst[1] = (value >> 8) & 0xff;
}
static void PutLE32(uint8_t* const dst, uint32_t value) {
PutLE16(dst + 0, (value >> 0) & 0xffff);
PutLE16(dst + 2, (value >> 16) & 0xffff);
}
#define BMP_HEADER_SIZE 54
static int WriteBMP(FILE* fout, const WebPDecBuffer* const buffer) {
const int has_alpha = (buffer->colorspace != MODE_BGR);
const uint32_t width = buffer->width;
const uint32_t height = buffer->height;
const uint8_t* const rgba = buffer->u.RGBA.rgba;
const int stride = buffer->u.RGBA.stride;
const size_t bytes_per_px = has_alpha ? 4 : 3;
uint32_t y;
const int line_size = bytes_per_px * width;
const int bmp_stride = (line_size + 3) & ~3; // pad to 4
const uint32_t total_size = bmp_stride * height + BMP_HEADER_SIZE;
uint8_t bmp_header[BMP_HEADER_SIZE] = { 0 };
// bitmap file header
PutLE16(bmp_header + 0, 0x4d42); // signature 'BM'
PutLE32(bmp_header + 2, total_size); // size including header
PutLE32(bmp_header + 6, 0); // reserved
PutLE32(bmp_header + 10, BMP_HEADER_SIZE); // offset to pixel array
// bitmap info header
PutLE32(bmp_header + 14, 40); // DIB header size
PutLE32(bmp_header + 18, width); // dimensions
PutLE32(bmp_header + 22, -(int)height); // vertical flip!
PutLE16(bmp_header + 26, 1); // number of planes
PutLE16(bmp_header + 28, bytes_per_px * 8); // bits per pixel
PutLE32(bmp_header + 30, 0); // no compression (BI_RGB)
PutLE32(bmp_header + 34, 0); // image size (dummy)
PutLE32(bmp_header + 38, 2400); // x pixels/meter
PutLE32(bmp_header + 42, 2400); // y pixels/meter
PutLE32(bmp_header + 46, 0); // number of palette colors
PutLE32(bmp_header + 50, 0); // important color count
// TODO(skal): color profile
// write header
if (fwrite(bmp_header, sizeof(bmp_header), 1, fout) != 1) {
return 0;
}
// write pixel array
for (y = 0; y < height; ++y) {
if (fwrite(rgba + y * stride, line_size, 1, fout) != 1) {
return 0;
}
// write padding zeroes
if (bmp_stride != line_size) {
const uint8_t zeroes[3] = { 0 };
if (fwrite(zeroes, bmp_stride - line_size, 1, fout) != 1) {
return 0;
}
}
}
return 1;
}
#undef BMP_HEADER_SIZE
#define NUM_IFD_ENTRIES 15
#define EXTRA_DATA_SIZE 16
// 10b for signature/header + n * 12b entries + 4b for IFD terminator:
#define EXTRA_DATA_OFFSET (10 + 12 * NUM_IFD_ENTRIES + 4)
#define TIFF_HEADER_SIZE (EXTRA_DATA_OFFSET + EXTRA_DATA_SIZE)
static int WriteTIFF(FILE* fout, const WebPDecBuffer* const buffer) {
const int has_alpha = (buffer->colorspace != MODE_RGB);
const uint32_t width = buffer->width;
const uint32_t height = buffer->height;
const uint8_t* const rgba = buffer->u.RGBA.rgba;
const int stride = buffer->u.RGBA.stride;
const uint8_t bytes_per_px = has_alpha ? 4 : 3;
// For non-alpha case, we omit tag 0x152 (ExtraSamples).
const uint8_t num_ifd_entries = has_alpha ? NUM_IFD_ENTRIES
: NUM_IFD_ENTRIES - 1;
uint8_t tiff_header[TIFF_HEADER_SIZE] = {
0x49, 0x49, 0x2a, 0x00, // little endian signature
8, 0, 0, 0, // offset to the unique IFD that follows
// IFD (offset = 8). Entries must be written in increasing tag order.
num_ifd_entries, 0, // Number of entries in the IFD (12 bytes each).
0x00, 0x01, 3, 0, 1, 0, 0, 0, 0, 0, 0, 0, // 10: Width (TBD)
0x01, 0x01, 3, 0, 1, 0, 0, 0, 0, 0, 0, 0, // 22: Height (TBD)
0x02, 0x01, 3, 0, bytes_per_px, 0, 0, 0, // 34: BitsPerSample: 8888
EXTRA_DATA_OFFSET + 0, 0, 0, 0,
0x03, 0x01, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0, // 46: Compression: none
0x06, 0x01, 3, 0, 1, 0, 0, 0, 2, 0, 0, 0, // 58: Photometric: RGB
0x11, 0x01, 4, 0, 1, 0, 0, 0, // 70: Strips offset:
TIFF_HEADER_SIZE, 0, 0, 0, // data follows header
0x12, 0x01, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0, // 82: Orientation: topleft
0x15, 0x01, 3, 0, 1, 0, 0, 0, // 94: SamplesPerPixels
bytes_per_px, 0, 0, 0,
0x16, 0x01, 3, 0, 1, 0, 0, 0, 0, 0, 0, 0, // 106: Rows per strip (TBD)
0x17, 0x01, 4, 0, 1, 0, 0, 0, 0, 0, 0, 0, // 118: StripByteCount (TBD)
0x1a, 0x01, 5, 0, 1, 0, 0, 0, // 130: X-resolution
EXTRA_DATA_OFFSET + 8, 0, 0, 0,
0x1b, 0x01, 5, 0, 1, 0, 0, 0, // 142: Y-resolution
EXTRA_DATA_OFFSET + 8, 0, 0, 0,
0x1c, 0x01, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0, // 154: PlanarConfiguration
0x28, 0x01, 3, 0, 1, 0, 0, 0, 2, 0, 0, 0, // 166: ResolutionUnit (inch)
0x52, 0x01, 3, 0, 1, 0, 0, 0, 1, 0, 0, 0, // 178: ExtraSamples: rgbA
0, 0, 0, 0, // 190: IFD terminator
// EXTRA_DATA_OFFSET:
8, 0, 8, 0, 8, 0, 8, 0, // BitsPerSample
72, 0, 0, 0, 1, 0, 0, 0 // 72 pixels/inch, for X/Y-resolution
};
uint32_t y;
// Fill placeholders in IFD:
PutLE32(tiff_header + 10 + 8, width);
PutLE32(tiff_header + 22 + 8, height);
PutLE32(tiff_header + 106 + 8, height);
PutLE32(tiff_header + 118 + 8, width * bytes_per_px * height);
if (!has_alpha) PutLE32(tiff_header + 178, 0); // IFD terminator
// write header
if (fwrite(tiff_header, sizeof(tiff_header), 1, fout) != 1) {
return 0;
}
// write pixel values
for (y = 0; y < height; ++y) {
if (fwrite(rgba + y * stride, bytes_per_px, width, fout) != width) {
return 0;
}
}
return 1;
}
#undef TIFF_HEADER_SIZE
#undef EXTRA_DATA_OFFSET
#undef EXTRA_DATA_SIZE
#undef NUM_IFD_ENTRIES
static int WriteAlphaPlane(FILE* fout, const WebPDecBuffer* const buffer) {
const uint32_t width = buffer->width;
const uint32_t height = buffer->height;
const unsigned char* const a = buffer->u.YUVA.a;
const int a_stride = buffer->u.YUVA.a_stride;
uint32_t y;
assert(a != NULL);
fprintf(fout, "P5\n%d %d\n255\n", width, height);
for (y = 0; y < height; ++y) {
if (fwrite(a + y * a_stride, width, 1, fout) != 1) {
return 0;
}
}
return 1;
}
// format=PGM: save a grayscale PGM file using the IMC4 layout
// (http://www.fourcc.org/yuv.php#IMC4). This is a very convenient format for
// viewing the samples, esp. for odd dimensions.
// format=YUV: just save the Y/U/V/A planes sequentially without header.
static int WritePGMOrYUV(FILE* fout, const WebPDecBuffer* const buffer,
OutputFileFormat format) {
const int width = buffer->width;
const int height = buffer->height;
const WebPYUVABuffer* const yuv = &buffer->u.YUVA;
int ok = 1;
int y;
const int pad = (format == YUV) ? 0 : 1;
const int uv_width = (width + 1) / 2;
const int uv_height = (height + 1) / 2;
const int out_stride = (width + pad) & ~pad;
const int a_height = yuv->a ? height : 0;
if (format == PGM) {
fprintf(fout, "P5\n%d %d\n255\n",
out_stride, height + uv_height + a_height);
}
for (y = 0; ok && y < height; ++y) {
ok &= (fwrite(yuv->y + y * yuv->y_stride, width, 1, fout) == 1);
if (format == PGM) {
if (width & 1) fputc(0, fout); // padding byte
}
}
if (format == PGM) { // IMC4 layout
for (y = 0; ok && y < uv_height; ++y) {
ok &= (fwrite(yuv->u + y * yuv->u_stride, uv_width, 1, fout) == 1);
ok &= (fwrite(yuv->v + y * yuv->v_stride, uv_width, 1, fout) == 1);
}
} else {
for (y = 0; ok && y < uv_height; ++y) {
ok &= (fwrite(yuv->u + y * yuv->u_stride, uv_width, 1, fout) == 1);
}
for (y = 0; ok && y < uv_height; ++y) {
ok &= (fwrite(yuv->v + y * yuv->v_stride, uv_width, 1, fout) == 1);
}
}
for (y = 0; ok && y < a_height; ++y) {
ok &= (fwrite(yuv->a + y * yuv->a_stride, width, 1, fout) == 1);
if (format == PGM) {
if (width & 1) fputc(0, fout); // padding byte
}
}
return ok;
}
static void SaveOutput(const WebPDecBuffer* const buffer,
OutputFileFormat format, const char* const out_file) {
FILE* fout = NULL;
int needs_open_file = 1;
int ok = 1;
Stopwatch stop_watch;
if (verbose)
StopwatchReadAndReset(&stop_watch);
#ifdef HAVE_WINCODEC_H
needs_open_file = (format != PNG);
#endif
if (needs_open_file) {
fout = fopen(out_file, "wb");
if (!fout) {
fprintf(stderr, "Error opening output file %s\n", out_file);
return;
}
}
if (format == PNG) {
#ifdef HAVE_WINCODEC_H
ok &= WritePNG(out_file, buffer);
#else
ok &= WritePNG(fout, buffer);
#endif
} else if (format == PAM) {
ok &= WritePPM(fout, buffer, 1);
} else if (format == PPM) {
ok &= WritePPM(fout, buffer, 0);
} else if (format == BMP) {
ok &= WriteBMP(fout, buffer);
} else if (format == TIFF) {
ok &= WriteTIFF(fout, buffer);
} else if (format == PGM || format == YUV) {
ok &= WritePGMOrYUV(fout, buffer, format);
} else if (format == ALPHA_PLANE_ONLY) {
ok &= WriteAlphaPlane(fout, buffer);
}
if (fout) {
fclose(fout);
}
if (ok) {
printf("Saved file %s\n", out_file);
if (verbose) {
const double write_time = StopwatchReadAndReset(&stop_watch);
printf("Time to write output: %.3fs\n", write_time);
}
} else {
fprintf(stderr, "Error writing file %s !!\n", out_file);
}
}
static void Help(void) {
printf("Usage: dwebp in_file [options] [-o out_file]\n\n"
"Decodes the WebP image file to PNG format [Default]\n"
"Use following options to convert into alternate image formats:\n"
" -pam ......... save the raw RGBA samples as a color PAM\n"
" -ppm ......... save the raw RGB samples as a color PPM\n"
" -bmp ......... save as uncompressed BMP format\n"
" -tiff ........ save as uncompressed TIFF format\n"
" -pgm ......... save the raw YUV samples as a grayscale PGM\n"
" file with IMC4 layout\n"
" -yuv ......... save the raw YUV samples in flat layout\n"
"\n"
" Other options are:\n"
" -version .... print version number and exit.\n"
" -nofancy ..... don't use the fancy YUV420 upscaler.\n"
" -nofilter .... disable in-loop filtering.\n"
" -mt .......... use multi-threading\n"
" -crop <x> <y> <w> <h> ... crop output with the given rectangle\n"
" -scale <w> <h> .......... scale the output (*after* any cropping)\n"
" -alpha ....... only save the alpha plane.\n"
" -h ....... this help message.\n"
" -v ....... verbose (e.g. print encoding/decoding times)\n"
#ifndef WEBP_DLL
" -noasm ....... disable all assembly optimizations.\n"
#endif
);
}
static const char* const kStatusMessages[] = {
"OK", "OUT_OF_MEMORY", "INVALID_PARAM", "BITSTREAM_ERROR",
"UNSUPPORTED_FEATURE", "SUSPENDED", "USER_ABORT", "NOT_ENOUGH_DATA"
};
int main(int argc, const char *argv[]) {
const char *in_file = NULL;
const char *out_file = NULL;
WebPDecoderConfig config;
WebPDecBuffer* const output_buffer = &config.output;
WebPBitstreamFeatures* const bitstream = &config.input;
OutputFileFormat format = PNG;
int c;
if (!WebPInitDecoderConfig(&config)) {
fprintf(stderr, "Library version mismatch!\n");
return -1;
}
for (c = 1; c < argc; ++c) {
if (!strcmp(argv[c], "-h") || !strcmp(argv[c], "-help")) {
Help();
return 0;
} else if (!strcmp(argv[c], "-o") && c < argc - 1) {
out_file = argv[++c];
} else if (!strcmp(argv[c], "-alpha")) {
format = ALPHA_PLANE_ONLY;
} else if (!strcmp(argv[c], "-nofancy")) {
config.options.no_fancy_upsampling = 1;
} else if (!strcmp(argv[c], "-nofilter")) {
config.options.bypass_filtering = 1;
} else if (!strcmp(argv[c], "-pam")) {
format = PAM;
} else if (!strcmp(argv[c], "-ppm")) {
format = PPM;
} else if (!strcmp(argv[c], "-bmp")) {
format = BMP;
} else if (!strcmp(argv[c], "-tiff")) {
format = TIFF;
} else if (!strcmp(argv[c], "-version")) {
const int version = WebPGetDecoderVersion();
printf("%d.%d.%d\n",
(version >> 16) & 0xff, (version >> 8) & 0xff, version & 0xff);
return 0;
} else if (!strcmp(argv[c], "-pgm")) {
format = PGM;
} else if (!strcmp(argv[c], "-yuv")) {
format = YUV;
} else if (!strcmp(argv[c], "-mt")) {
config.options.use_threads = 1;
} else if (!strcmp(argv[c], "-crop") && c < argc - 4) {
config.options.use_cropping = 1;
config.options.crop_left = strtol(argv[++c], NULL, 0);
config.options.crop_top = strtol(argv[++c], NULL, 0);
config.options.crop_width = strtol(argv[++c], NULL, 0);
config.options.crop_height = strtol(argv[++c], NULL, 0);
} else if (!strcmp(argv[c], "-scale") && c < argc - 2) {
config.options.use_scaling = 1;
config.options.scaled_width = strtol(argv[++c], NULL, 0);
config.options.scaled_height = strtol(argv[++c], NULL, 0);
} else if (!strcmp(argv[c], "-v")) {
verbose = 1;
#ifndef WEBP_DLL
} else if (!strcmp(argv[c], "-noasm")) {
VP8GetCPUInfo = NULL;
#endif
} else if (argv[c][0] == '-') {
fprintf(stderr, "Unknown option '%s'\n", argv[c]);
Help();
return -1;
} else {
in_file = argv[c];
}
}
if (in_file == NULL) {
fprintf(stderr, "missing input file!!\n");
Help();
return -1;
}
{
Stopwatch stop_watch;
VP8StatusCode status = VP8_STATUS_OK;
int ok;
size_t data_size = 0;
const uint8_t* data = NULL;
if (!ExUtilReadFile(in_file, &data, &data_size)) return -1;
if (verbose)
StopwatchReadAndReset(&stop_watch);
status = WebPGetFeatures(data, data_size, bitstream);
if (status != VP8_STATUS_OK) {
goto end;
}
if (bitstream->has_animation) {
fprintf(stderr,
"Error! Decoding of an animated WebP file is not supported.\n"
" Use webpmux to extract the individual frames or\n"
" vwebp to view this image.\n");
}
switch (format) {
case PNG:
#ifdef HAVE_WINCODEC_H
output_buffer->colorspace = bitstream->has_alpha ? MODE_BGRA : MODE_BGR;
#else
output_buffer->colorspace = bitstream->has_alpha ? MODE_RGBA : MODE_RGB;
#endif
break;
case PAM:
output_buffer->colorspace = MODE_RGBA;
break;
case PPM:
output_buffer->colorspace = MODE_RGB; // drops alpha for PPM
break;
case BMP:
output_buffer->colorspace = bitstream->has_alpha ? MODE_BGRA : MODE_BGR;
break;
case TIFF: // note: force pre-multiplied alpha
output_buffer->colorspace =
bitstream->has_alpha ? MODE_rgbA : MODE_RGB;
break;
case PGM:
case YUV:
output_buffer->colorspace = bitstream->has_alpha ? MODE_YUVA : MODE_YUV;
break;
case ALPHA_PLANE_ONLY:
output_buffer->colorspace = MODE_YUVA;
break;
default:
free((void*)data);
return -1;
}
status = WebPDecode(data, data_size, &config);
if (verbose) {
const double decode_time = StopwatchReadAndReset(&stop_watch);
printf("Time to decode picture: %.3fs\n", decode_time);
}
end:
free((void*)data);
ok = (status == VP8_STATUS_OK);
if (!ok) {
fprintf(stderr, "Decoding of %s failed.\n", in_file);
fprintf(stderr, "Status: %d (%s)\n", status, kStatusMessages[status]);
return -1;
}
}
if (out_file) {
printf("Decoded %s. Dimensions: %d x %d%s. Now saving...\n", in_file,
output_buffer->width, output_buffer->height,
bitstream->has_alpha ? " (with alpha)" : "");
SaveOutput(output_buffer, format, out_file);
} else {
printf("File %s can be decoded (dimensions: %d x %d)%s.\n",
in_file, output_buffer->width, output_buffer->height,
bitstream->has_alpha ? " (with alpha)" : "");
printf("Nothing written; use -o flag to save the result as e.g. PNG.\n");
}
WebPFreeDecBuffer(output_buffer);
return 0;
}
//------------------------------------------------------------------------------