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#include <stdio.h>
#include "dct.h"
#define ENCODE 0
#define DECODE 1
#define MAXROWS 1024
#define MAXCOLS 768
#define HEADER 56
#define SOI_MK 0xFFD8 /* start of image */
#define SOF_MK 0xFFC0 /* start of frame */
#define EOI_MK 0xFFD9 /* end of image */
#define DRI_MK 0xFFDD /* restart interval */
#define get_size(fi) (((unsigned int)Image1[fi]) << 8) + (unsigned int)Image1[fi+1]
unsigned char Image1[MAXCOLS*3*MAXROWS+HEADER];
unsigned char clip(int value) {
if (value < 0) return (char) 0;
if (value > 255) return (char) 255;
return (unsigned char) value;
}
/* RGB -> YCbCr (also from BMP to JPEG) */
// Y = 0.299 R + 0.587 G + 0.114 B
unsigned char RGB2Y (unsigned char R, unsigned char G, unsigned char B) {
return clip(0.299 * R + 0.587 * G + 0.114 * B);
}
// Cb = - 0.1687 R - 0.3313 G + 0.5 B + 128
unsigned char RGB2Cb (unsigned char R, unsigned char G, unsigned char B) {
return clip(- 0.1687 * R - 0.3313 * G + 0.5 * B + 128);
}
//Cr = 0.5 R - 0.4187 G - 0.0813 B + 128
unsigned char RGB2Cr (unsigned char R, unsigned char G, unsigned char B) {
return clip(0.5 * R - 0.4187 * G - 0.0813 * B + 128);
}
/* RGB -> YCbCr (also from JPEG to BMP) */
// R = Y + 1.402 (Cr-128)
unsigned char YCbCr2R (unsigned char Y, unsigned char Cr) {
return clip(Y + 1.402 *(Cr-128));
}
// G = Y - 0.34414 (Cb-128) - 0.71414 (Cr-128)
unsigned char YCbCr2G (unsigned char Y, unsigned char Cb, unsigned char Cr) {
return clip(Y - 0.34414 *(Cb-128) - 0.71414 *(Cr-128));
}
// B = Y + 1.772 (Cb-128)
unsigned char YCbCr2B (unsigned char Y, unsigned char Cb) {
return clip(Y + 1.772 *(Cb-128));
}
int main(int argc, char *argv[]) {
int retval, i;
int workspace[DCTSIZE_BLOCK];
int type, hCounter = 0;
int x_size, y_size, offset, depth;
char *fileIn, *fileOut;
FILE *fI, *fO;
unsigned char ch, mrgb[3];
unsigned int aux;
/*******************************************************************************************/
/* Just for testing on the PC */
if(argc != 4)
{
printf("need more arguments");
return 0;
}
type = atoi(argv[1]);
fileIn = argv[2];
fileOut = argv[3];
if (NULL == (fI = fopen(fileIn, "rb"))){
printf("unable to open the file to read from (%s)",fileIn);
return 0;
}
if ((fO = fopen(fileOut,"wb")) == NULL) {
printf("unable to open the file to write (%s)",fileOut);
return 0;
}
/* Read the max possible size to the memory */
fread(Image1, sizeof(unsigned char), (MAXROWS*MAXCOLS*3+HEADER), fI);
/*******************************************************************************************/
/* The image must be in the memory by now */
switch(type) {
case ENCODE:
offset = ((int)Image1[13] << 24) + ((int)Image1[12] << 16) + ((int)Image1[11] << 8) + Image1[10];
x_size = ((int)Image1[21] << 24) + ((int)Image1[20] << 16) + ((int)Image1[19] << 8) + Image1[18];
y_size = ((int)Image1[25] << 24) + ((int)Image1[24] << 16) + ((int)Image1[23] << 8) + Image1[22];
depth = ((int)Image1[29] << 8) + Image1[28];
/**/ printf("Image Resolution: %d x %d x %i Offset: %i\n", x_size, y_size, depth, offset);
break;
case DECODE:
/* First find the SOI marker: */
aux = get_size(hCounter); hCounter+=2;
if (aux != SOI_MK)
{ printf("INFO:\tNO SOI marker!\n"); return 0;}
printf("%ld:\tINFO:\tFound the SOI marker!\n", hCounter);
/* Read first marker */
while( aux != SOF_MK)
{
aux = get_size(hCounter); hCounter+=2;
if(aux == SOF_MK)
{
get_size(hCounter); hCounter+=2; /* header size, don't care */
/* load basic image parameters */
hCounter++; /* precision, 8bit, don't care */
y_size = get_size(hCounter); hCounter+=2;
x_size = get_size(hCounter); hCounter+=2;
printf("\tINFO:\tImage size is %d by %d\n", x_size, y_size);
depth = Image1[hCounter]; /* # of components */
printf("\tINFO:\t");
switch (depth)
{
case 1:
printf("Monochrome");
break;
case 3:
printf("Color");
break;
default:
printf("Not a");
break;
}
printf(" JPEG image!\n");
return 0;
}
else
{
hCounter = hCounter + get_size(hCounter);
}
}
}
retval = 0;
type = ENCODE;
switch(type) {
case ENCODE:
// RGB -> YUV
// Convert to 8x8
// DCT
fdct(workspace);
// ZZ
// Q
// VLC (huffman)
break;
case DECODE:
// VLD (huffman)
// IQ
// ZZ
// IDCT
//idct(workspace);
// Convert 8x8 to lines
// YUV -> RGB
break;
}
return retval;
}
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