mirror of
https://github.com/webmproject/libwebp.git
synced 2024-12-25 21:28:22 +01:00
118 lines
2.7 KiB
C
118 lines
2.7 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/
|
|
// -----------------------------------------------------------------------------
|
|
//
|
|
// JPEG decode.
|
|
|
|
#include "./jpegdec.h"
|
|
|
|
#ifdef HAVE_CONFIG_H
|
|
#include "config.h"
|
|
#endif
|
|
|
|
#include <stdio.h>
|
|
|
|
#ifdef WEBP_HAVE_JPEG
|
|
#include <jpeglib.h>
|
|
#include <setjmp.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include "webp/encode.h"
|
|
|
|
struct my_error_mgr {
|
|
struct jpeg_error_mgr pub;
|
|
jmp_buf setjmp_buffer;
|
|
};
|
|
|
|
static void my_error_exit(j_common_ptr dinfo) {
|
|
struct my_error_mgr* myerr = (struct my_error_mgr*) dinfo->err;
|
|
(*dinfo->err->output_message) (dinfo);
|
|
longjmp(myerr->setjmp_buffer, 1);
|
|
}
|
|
|
|
int ReadJPEG(FILE* in_file, WebPPicture* const pic) {
|
|
int ok = 0;
|
|
int stride, width, height;
|
|
uint8_t* rgb = NULL;
|
|
uint8_t* row_ptr = NULL;
|
|
struct jpeg_decompress_struct dinfo;
|
|
struct my_error_mgr jerr;
|
|
JSAMPARRAY buffer;
|
|
|
|
dinfo.err = jpeg_std_error(&jerr.pub);
|
|
jerr.pub.error_exit = my_error_exit;
|
|
|
|
if (setjmp(jerr.setjmp_buffer)) {
|
|
Error:
|
|
jpeg_destroy_decompress(&dinfo);
|
|
goto End;
|
|
}
|
|
|
|
jpeg_create_decompress(&dinfo);
|
|
jpeg_stdio_src(&dinfo, in_file);
|
|
jpeg_read_header(&dinfo, TRUE);
|
|
|
|
dinfo.out_color_space = JCS_RGB;
|
|
dinfo.dct_method = JDCT_IFAST;
|
|
dinfo.do_fancy_upsampling = TRUE;
|
|
|
|
jpeg_start_decompress(&dinfo);
|
|
|
|
if (dinfo.output_components != 3) {
|
|
goto Error;
|
|
}
|
|
|
|
width = dinfo.output_width;
|
|
height = dinfo.output_height;
|
|
stride = dinfo.output_width * dinfo.output_components * sizeof(*rgb);
|
|
|
|
rgb = (uint8_t*)malloc(stride * height);
|
|
if (rgb == NULL) {
|
|
goto End;
|
|
}
|
|
row_ptr = rgb;
|
|
|
|
buffer = (*dinfo.mem->alloc_sarray) ((j_common_ptr) &dinfo,
|
|
JPOOL_IMAGE, stride, 1);
|
|
if (buffer == NULL) {
|
|
goto End;
|
|
}
|
|
|
|
while (dinfo.output_scanline < dinfo.output_height) {
|
|
if (jpeg_read_scanlines(&dinfo, buffer, 1) != 1) {
|
|
goto End;
|
|
}
|
|
memcpy(row_ptr, buffer[0], stride);
|
|
row_ptr += stride;
|
|
}
|
|
|
|
jpeg_finish_decompress(&dinfo);
|
|
jpeg_destroy_decompress(&dinfo);
|
|
|
|
// WebP conversion.
|
|
pic->width = width;
|
|
pic->height = height;
|
|
ok = WebPPictureImportRGB(pic, rgb, stride);
|
|
|
|
End:
|
|
if (rgb) {
|
|
free(rgb);
|
|
}
|
|
return ok;
|
|
}
|
|
#else // !WEBP_HAVE_JPEG
|
|
int ReadJPEG(FILE* in_file, struct WebPPicture* const pic) {
|
|
(void)in_file;
|
|
(void)pic;
|
|
fprintf(stderr, "JPEG support not compiled. Please install the libjpeg "
|
|
"development package before building.\n");
|
|
return 0;
|
|
}
|
|
#endif // WEBP_HAVE_JPEG
|
|
|
|
// -----------------------------------------------------------------------------
|