| 0,0 → 1,137 |
|---|
| /* Zgv v2.7 - GIF, JPEG and PBM/PGM/PPM viewer, for VGA PCs running Linux. |
| * Copyright (C) 1993-1995 Russell Marks. See README for license details. |
| * |
| * readjpeg.c - interface to the IJG's JPEG software, derived from |
| * their example.c. |
| */ |
| |
| #include <stdio.h> |
| #include <string.h> |
| #include <unistd.h> |
| #include <stdlib.h> |
| #include <setjmp.h> |
| #include <sys/file.h> /* for open et al */ |
| #include <jpeglib.h> |
| #include "libmgfx.h" |
| |
| static mgfx_image_t * the_image; |
| static FILE * global_jpeg_infile; |
| static struct jpeg_decompress_struct cinfo; |
| |
| struct my_error_mgr |
| { |
| struct jpeg_error_mgr pub; |
| jmp_buf setjmp_buffer; |
| }; |
| |
| typedef struct my_error_mgr * my_error_ptr; |
| |
| static void jpegerr(char *msgtext) |
| { |
| } |
| |
| static void my_error_exit(j_common_ptr cinfo) |
| { |
| my_error_ptr myerr=(my_error_ptr) cinfo->err; |
| char buf[JMSG_LENGTH_MAX]; |
| (*cinfo->err->format_message)(cinfo,buf); |
| jpegerr(buf); |
| longjmp(myerr->setjmp_buffer, 1); |
| } |
| |
| static void my_output_message(j_common_ptr cinfo) |
| { |
| } |
| |
| static void aborted_file_jpeg_cleanup() |
| { |
| jpeg_destroy_decompress(&cinfo); |
| fclose(global_jpeg_infile); |
| } |
| |
| int read_JPEG_file(FILE * in,mgfx_image_t * img) |
| { |
| struct my_error_mgr jerr; |
| int row_stride; |
| int tmp,f; |
| unsigned char *ptr; |
| the_image=img; |
| if((img->pal=(byte *)malloc(768))==NULL) return(_PICERR_NOMEM); |
| cinfo.err=jpeg_std_error(&jerr.pub); |
| jerr.pub.error_exit=my_error_exit; |
| jerr.pub.output_message=my_output_message; |
| if(setjmp(jerr.setjmp_buffer)) |
| { |
| jpeg_destroy_decompress(&cinfo); |
| free(img->pal); |
| return(_PICERR_CORRUPT); |
| } |
| jpeg_create_decompress(&cinfo); |
| jpeg_stdio_src(&cinfo,in); |
| jpeg_read_header(&cinfo,TRUE); |
| cinfo.dct_method=JDCT_FLOAT; |
| img->bpp=24; |
| if(cinfo.jpeg_color_space==JCS_GRAYSCALE) |
| { |
| cinfo.out_color_space=JCS_GRAYSCALE; |
| cinfo.desired_number_of_colors=256; |
| cinfo.quantize_colors=FALSE; |
| cinfo.two_pass_quantize=FALSE; |
| img->bpp=8; |
| for(f=0;f<256;f++) |
| img->pal[f]=img->pal[256+f]=img->pal[512+f]=f; |
| } |
| img->width=cinfo.image_width; |
| img->height=cinfo.image_height; |
| img->the_image=(byte *)malloc(((img->bpp+7)/8)*img->width*img->height); |
| if(img->the_image==NULL) |
| { |
| jpegerr("Out of memory"); |
| longjmp(jerr.setjmp_buffer,1); |
| } |
| jpeg_start_decompress(&cinfo); |
| if(img->bpp==8 && cinfo.jpeg_color_space!=JCS_GRAYSCALE) |
| for(f=0;f<cinfo.actual_number_of_colors;f++) |
| { |
| img->pal[ f]=cinfo.colormap[0][f]; |
| img->pal[256+f]=cinfo.colormap[1][f]; |
| img->pal[512+f]=cinfo.colormap[2][f]; |
| } |
| ptr=img->the_image; |
| row_stride=((img->bpp+7)/8)*img->width; |
| if(img->bpp==8) |
| while(cinfo.output_scanline<img->height) |
| { |
| jpeg_read_scanlines(&cinfo,&ptr,1); |
| ptr+=row_stride; |
| } |
| else |
| while(cinfo.output_scanline<img->height) |
| { |
| jpeg_read_scanlines(&cinfo,&ptr,1); |
| for(f=0;f<img->width;f++) { tmp=*ptr; *ptr=ptr[2]; ptr[2]=tmp; ptr+=3; } |
| } |
| jpeg_finish_decompress(&cinfo); |
| jpeg_destroy_decompress(&cinfo); |
| return(_PIC_OK); |
| } |
| |
| static struct mgfx_image_format this_fmt_1={ |
| "JPEG", |
| "jpg", |
| read_JPEG_file, |
| NULL, |
| }; |
| |
| static struct mgfx_image_format this_fmt_2={ |
| "JPEG", |
| "jpeg", |
| read_JPEG_file, |
| NULL, |
| }; |
| |
| void mgfx_register_jpeg(void) |
| { |
| register_image_format(&this_fmt_1); |
| register_image_format(&this_fmt_2); |
| } |