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/*
* djpeg.c
*
* Copyright (C) 1991-1997, Thomas G. Lane.
* This file is part of the Independent JPEG Group's software.
* For conditions of distribution and use, see the accompanying README file.
*
* This file contains a command-line user interface for the JPEG decompressor.
* It should work on any system with Unix- or MS-DOS-style command lines.
*
* Two different command line styles are permitted, depending on the
* compile-time switch TWO_FILE_COMMANDLINE:
* djpeg [options] inputfile outputfile
* djpeg [options] [inputfile]
* In the second style, output is always to standard output, which you'd
* normally redirect to a file or pipe to some other program. Input is
* either from a named file or from standard input (typically redirected).
* The second style is convenient on Unix but is unhelpful on systems that
* don't support pipes. Also, you MUST use the first style if your system
* doesn't do binary I/O to stdin/stdout.
* To simplify script writing, the "-outfile" switch is provided. The syntax
* djpeg [options] -outfile outputfile inputfile
* works regardless of which command line style is used.
*/
#include /* Common decls for cjpeg/djpeg applications */
#include /* for version message */
#include /* to declare isprint() */
#include "ioutil.h"
/* Create the add-on message string table. */
#define JMESSAGE(code,string) string ,
static const char * const cdjpeg_message_table[] = {
#include "cderror.h"
NULL
};
/*
* This list defines the known output image formats
* (not all of which need be supported by a given version).
* You can change the default output format by defining DEFAULT_FMT;
* indeed, you had better do so if you undefine PPM_SUPPORTED.
*/
typedef enum {
FMT_BMP, /* BMP format (Windows flavor) */
FMT_GIF, /* GIF format */
FMT_OS2, /* BMP format (OS/2 flavor) */
FMT_PPM, /* PPM/PGM (PBMPLUS formats) */
FMT_RLE, /* RLE format */
FMT_TARGA, /* Targa format */
FMT_TIFF /* TIFF format */
} IMAGE_FORMATS;
#ifndef DEFAULT_FMT /* so can override from CFLAGS in Makefile */
#define DEFAULT_FMT FMT_PPM
#endif
static IMAGE_FORMATS requested_fmt;
/*
* Marker processor for COM and interesting APPn markers.
* This replaces the library's built-in processor, which just skips the marker.
* We want to print out the marker as text, to the extent possible.
* Note this code relies on a non-suspending data source.
*/
LOCAL(unsigned int)
jpeg_getc (j_decompress_ptr cinfo)
/* Read next byte */
{
struct jpeg_source_mgr * datasrc = cinfo->src;
if (datasrc->bytes_in_buffer == 0) {
if (! (*datasrc->fill_input_buffer) (cinfo))
ERREXIT(cinfo, JERR_CANT_SUSPEND);
}
datasrc->bytes_in_buffer--;
return GETJOCTET(*datasrc->next_input_byte++);
}
METHODDEF(boolean)
print_text_marker (j_decompress_ptr cinfo)
{
boolean traceit = (cinfo->err->trace_level >= 1);
INT32 length;
unsigned int ch;
unsigned int lastch = 0;
length = jpeg_getc(cinfo) << 8;
length += jpeg_getc(cinfo);
length -= 2; /* discount the length word itself */
if (traceit) {
if (cinfo->unread_marker == JPEG_COM)
fprintf(stderr, "Comment, length %ld:\n", (long) length);
else /* assume it is an APPn otherwise */
fprintf(stderr, "APP%d, length %ld:\n",
cinfo->unread_marker - JPEG_APP0, (long) length);
}
while (--length >= 0) {
ch = jpeg_getc(cinfo);
if (traceit) {
/* Emit the character in a readable form.
* Nonprintables are converted to \nnn form,
* while \ is converted to \\.
* Newlines in CR, CR/LF, or LF form will be printed as one newline.
*/
if (ch == '\r') {
fprintf(stderr, "\n");
} else if (ch == '\n') {
if (lastch != '\r')
fprintf(stderr, "\n");
} else if (ch == '\\') {
fprintf(stderr, "\\\\");
} else if (isprint(ch)) {
putc(ch, stderr);
} else {
fprintf(stderr, "\\%03o", ch);
}
lastch = ch;
}
}
if (traceit)
fprintf(stderr, "\n");
return TRUE;
}
/*
* The main program.
*/
int inputimgjpg(char *filename,unsigned char **RGB,int *NY,int *NX)
{
int dim,i,row_stride;
unsigned char *rgbp;
struct jpeg_decompress_struct cinfo;
struct jpeg_error_mgr jerr;
JSAMPARRAY buffer; /* Output row buffer */
int file_index;
FILE * input_file;
FILE * output_file;
JDIMENSION num_scanlines;
/* Initialize the JPEG decompression object with default error handling. */
cinfo.err = jpeg_std_error(&jerr);
jpeg_create_decompress(&cinfo);
/* Add some application-specific error messages (from cderror.h) */
jerr.addon_message_table = cdjpeg_message_table;
jerr.first_addon_message = JMSG_FIRSTADDONCODE;
jerr.last_addon_message = JMSG_LASTADDONCODE;
/* Insert custom marker processor for COM and APP12.
* APP12 is used by some digital camera makers for textual info,
* so we provide the ability to display it as text.
* If you like, additional APPn marker types can be selected for display,
* but don't try to override APP0 or APP14 this way (see libjpeg.doc).
*/
jpeg_set_marker_processor(&cinfo, JPEG_COM, print_text_marker);
jpeg_set_marker_processor(&cinfo, JPEG_APP0+12, print_text_marker);
/* Scan command line to find file names. */
/* It is convenient to use just one switch-parsing routine, but the switch
* values read here are ignored; we will rescan the switches after opening
* the input file.
* (Exception: tracing level set here controls verbosity for COM markers
* found during jpeg_read_header...)
*/
/* Open the input file. */
if ((input_file = fopen(filename, READ_BINARY)) == NULL) {
fprintf(stderr, "can't open %s\n", filename);
exit(EXIT_FAILURE);
}
/* Specify data source for decompression */
jpeg_stdio_src(&cinfo, input_file);
/* Read file header, set default decompression parameters */
(void) jpeg_read_header(&cinfo, TRUE);
/* Start decompressor */
(void) jpeg_start_decompress(&cinfo);
switch (cinfo.out_color_space)
{
case JCS_GRAYSCALE:
dim = 1;
*NY = (int) cinfo.output_height;
*NX = (int) cinfo.output_width;
*RGB = (unsigned char *)calloc((*NY)*(*NX)*dim,sizeof(unsigned char));
rgbp = *RGB;
break;
case JCS_RGB:
dim = 3;
*NY = (int) cinfo.output_height;
*NX = (int) cinfo.output_width;
*RGB = (unsigned char *)calloc((*NY)*(*NX)*dim,sizeof(unsigned char));
rgbp = *RGB;
break;
default:
ERREXIT(&cinfo, JERR_PPM_COLORSPACE);
}
row_stride = cinfo.output_width * cinfo.out_color_components;
buffer = (*cinfo.mem->alloc_sarray)
((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);
/* Process data */
while (cinfo.output_scanline < cinfo.output_height) {
num_scanlines = jpeg_read_scanlines(&cinfo, buffer, 1);
for (i=0;i