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| #include <stdio.h>
#include <jpeglib.h>
#include <stdlib.h>
/* dimensions of the image we want to write */
int width = 640; //L'image à charger est bien en 480*640
int height = 480;
int bytes_per_pixel = 3; /* or 1 for GRACYSCALE images */
J_COLOR_SPACE color_space = JCS_RGB; /* or JCS_GRAYSCALE for grayscale images */
int read_jpeg_file( char *filename )
{
/* these are standard libjpeg structures for reading(decompression) */
struct jpeg_decompress_struct cinfo;
struct jpeg_error_mgr jerr;
/* libjpeg data structure for storing one row, that is, scanline of an image */
JSAMPROW row_pointer[1];
FILE *infile = fopen( filename, "rb" );
FILE *second = fopen( "test2.jpeg", "wb" );
unsigned long location = 0;
int i = 0;
if ( !infile )
{
printf("Error opening jpeg file %s\n!", filename );
return -1;
}
/* here we set up the standard libjpeg error handler */
cinfo.err = jpeg_std_error( &jerr );
/* setup decompression process and source, then read JPEG header */
jpeg_create_decompress( &cinfo );
/* this makes the library read from infile */
jpeg_stdio_src( &cinfo, infile );
/* reading the image header which contains image information */
jpeg_read_header( &cinfo, TRUE );
printf( "JPEG File Information: \n" );
printf( "Image width and height: %d pixels and %d pixels.\n", cinfo.image_width, cinfo.image_height );
printf( "Color components per pixel: %d.\n", cinfo.num_components );
printf( "Color space: %d.\n", cinfo.jpeg_color_space );
/* Start decompression jpeg here */
jpeg_start_decompress( &cinfo );
/* now actually read the jpeg into the raw buffer */
row_pointer[0] = (unsigned char *)malloc( cinfo.output_width*cinfo.num_components );
/* read one scan line at a time */
while( cinfo.output_scanline < cinfo.image_height )
{
jpeg_read_scanlines( &cinfo, row_pointer, 1 );
for(i=0; i<640;i++) //changer 640 pour w*components
{
fprintf(second, "%i", row_pointer[0][i]);
}
}
/* wrap up decompression, destroy objects, free pointers and close open files */
jpeg_finish_decompress( &cinfo );
jpeg_destroy_decompress( &cinfo );
free( row_pointer[0] );
fclose( infile );
fclose( second );
return 1;
}
int write_jpeg_file( char *filename )
{
struct jpeg_compress_struct cinfo;
struct jpeg_error_mgr jerr;
/* this is a pointer to one row of image data */
//JSAMPROW row_pointer[1];
FILE *outfile = fopen( filename, "wb" );
FILE *file = fopen("test2.jpeg", "rb" );
if ( !outfile )
{
printf("Error opening output jpeg file %s\n!", filename );
return -1;
}
cinfo.err = jpeg_std_error( &jerr );
jpeg_create_compress(&cinfo);
jpeg_stdio_dest(&cinfo, outfile);
/* Setting the parameters of the output file here */
cinfo.image_width = width;
printf("%d \n", width);
cinfo.image_height = height;
printf("%d \n", height);
cinfo.input_components = bytes_per_pixel;
printf("%d \n", bytes_per_pixel);
cinfo.in_color_space = color_space;
printf("%d \n", color_space);
/* default compression parameters, we shouldn't be worried about these */
jpeg_set_defaults( &cinfo );
/* Now do the compression .. */
jpeg_start_compress( &cinfo, TRUE );
//unsigned char *row_pointer;
//row_pointer[0] = (unsigned char *)malloc( cinfo.image_width*cinfo.input_components );
char *a;
a = (unsigned char*)malloc( cinfo.image_width*cinfo.input_components*cinfo.image_height );
int i;
unsigned char *line;
while( cinfo.next_scanline < cinfo.image_height )
{
fgets(a, cinfo.image_width*cinfo.input_components, file);
jpeg_write_scanlines( &cinfo, &a, 1);
}
/* similar to read file, clean up after we're done compressing */
jpeg_finish_compress( &cinfo );
jpeg_destroy_compress( &cinfo );
fclose( outfile );
/* success code is 1! */
return 1;
}
int main()
{
char *infilename = "lecture.jpeg", *outfilename = "ecriture.jpeg";
/* Try opening a jpeg*/
if( read_jpeg_file( infilename ) > 0 )
{
/* then copy it to another file */
if( write_jpeg_file( outfilename ) < 0 ) return -1;
}
else return -1;
return 0;
} |
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