diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/jpeg.c | 38 |
1 files changed, 27 insertions, 11 deletions
@@ -2,21 +2,33 @@ #include <stdio.h> #include <stdlib.h> #include <assert.h> +#include <setjmp.h> +#include <string.h> #include "jpeglib.h" #include "jpeg.h" +struct error_mgr{ + struct jpeg_error_mgr pub; + jmp_buf jmp_buffer; +}; + +static void error_exit(j_common_ptr cinfo){ + printf("\nerror!\n"); + exit(1); +} + unsigned char *loadjpeg(char *filename, int *width, int *height){ struct jpeg_decompress_struct cinfo; - struct jpeg_error_mgr jerr; + struct error_mgr jerr; FILE *infile; JSAMPARRAY buffer; int row_stride; int i = 0; int j; - int x, y; + int y; unsigned char *retbuf; if((infile = fopen(filename, "rb")) == NULL){ @@ -24,14 +36,23 @@ unsigned char *loadjpeg(char *filename, int *width, int *height){ exit(1); } - cinfo.err = jpeg_std_error(&jerr); + cinfo.err = jpeg_std_error(&jerr.pub); + jerr.pub.error_exit = error_exit; + jpeg_create_decompress(&cinfo); jpeg_stdio_src(&cinfo, infile); jpeg_read_header(&cinfo, TRUE); + + /* parameters */ cinfo.do_fancy_upsampling = 0; cinfo.do_block_smoothing = 0; cinfo.quantize_colors = 0; cinfo.dct_method = JDCT_IFAST; + + jpeg_calc_output_dimensions(&cinfo); + row_stride = cinfo.output_width * cinfo.output_components; + buffer = (*cinfo.mem->alloc_sarray)((j_common_ptr)&cinfo, JPOOL_IMAGE, row_stride, 4); + jpeg_start_decompress(&cinfo); *width = cinfo.output_width; *height = cinfo.output_height; @@ -41,16 +62,11 @@ unsigned char *loadjpeg(char *filename, int *width, int *height){ fprintf(stderr, "TODO: greyscale images are not supported\n"); exit(1); } - row_stride = cinfo.output_width * cinfo.output_components; - buffer = (*cinfo.mem->alloc_sarray)((j_common_ptr)&cinfo, JPOOL_IMAGE, row_stride, 16); for(y = 0; y < cinfo.output_height; ){ - int n = jpeg_read_scanlines(&cinfo, buffer, 16); + int n = jpeg_read_scanlines(&cinfo, buffer, 4); for(j = 0; j < n; j++){ - for(x = 0; x < row_stride;){ - retbuf[i++] = buffer[j][x++]; - retbuf[i++] = buffer[j][x++]; - retbuf[i++] = buffer[j][x++]; - } + memcpy(&retbuf[i], buffer[j], row_stride); + i += row_stride; } y += n; } |