yuv2ppm.c

linux 嵌入式原代码

/*
 * file converter
 *
 * How to compile:
 *   gcc -o yuv2ppm yuv2ppm
 *
 * Usage:
 *   $ yuv2ppm < cap001.yuv > cap001.ppm
 *   $ yuv2ppm -i < cap001.yuv > cap001.ppm
 */
#include <stdio.h>
#include <unistd.h>
#include <errno.h>

#define SHOW_MAXMIN

#define FW	720
#define FH	480
#define PIXCEL_NUM (FW*FH)

int opt_i=0, opt_s=0, opt_v=0, opt_W=FW, opt_H=FH;

unsigned char frame[PIXCEL_NUM*3];

unsigned char yuvbuf[PIXCEL_NUM*2];

static void pixcel_to_buffer(int n, int r, int g, int b)
{
    frame[n*3]   = r;
    frame[n*3+1] = g;
    frame[n*3+2] = b;
}

static void pixcel_write(void)
{
    int x, y, p, n, r, g, b;

    n = 0;
    for(y=0; y<opt_H; y++){
	for(x=0; x<opt_W; x++){
	    if( opt_i ){
		if( (y & 1) == 0 )
		    p = (y >> 1) * opt_W + x;
		else
		    p = (opt_H/2 + (y >> 1)) * opt_W + x;
	    }else{
		p = y * opt_W + x;
	    }
	    r = frame[p*3];
	    g = frame[p*3+1];
	    b = frame[p*3+2];
	    if( n++ % 5 == 0 )
		printf("\n%3d %3d %3d ", r, g, b);
	    else
		printf("%3d %3d %3d ", r, g, b);
	}
    }
}

#ifdef NEVER
static void YCbCr2RGB_xx(int n, int Y, int Cb, int Cr, int *r, int *g, int *b)
{

    Cb = ((Cb-128) * 3) >> 1;	/* fix me */
    Cr = ((Cr-128) * 3) >> 1;	/* fix me */

    /*
     * Y  =  0.587 * G + 0.114 * B + 0.299 * R
     * Cb = -0.587 * G + 0.886 * B - 0.299 * R
     * Cr =  0.587 * G - 0.114 * B - 0.701 * R
     *
     * R  = Y + Cr
     * G  = Y - 0.194 * Cb - 0.509 * Cr
     * B  = Y + Cb
     */

    *r = Y + Cr;
    *g = (Y * 1000 - 194 * Cb - 509 * Cr) / 1000;
    *b = Y + Cb;

    if( *r < 0 || *g < 0 || *b < 0 || *r > 255 || *g > 255 || *b > 255 ){
	if( opt_v )
	    fprintf(stderr, "pixcel(%d,%d): Y=%d Cb=%d Cr=%d rgb=(%d,%d,%d)\n",
		    n % opt_W, n / opt_W, Y, Cb, Cr, *r, *g, *b);
	if( *r < 0 )
	    *r = 0;
	if( *r > 255 )
	    *r = 255;
	if( *g < 0 )
	    *g = 0;
	if( *g > 255 )
	    *g = 255;
	if( *b < 0 )
	    *b = 0;
	if( *b > 255 )
	    *b = 255;
    }
}
#endif

static void YCbCr2RGB_8fs(int n, int Y, int Cb, int Cr, int *r, int *g, int *b)
{

    Cb = Cb-128;
    Cr = Cr-128;

    /*
     * Y =  0.299R + 0.587G + 0.114B
     * U = -0.169R - 0.331G + 0.500B
     * V =  0.500R - 0.419G - 0.081B
     *
     * R = 1.000Y          + 1.402V
     * G = 1.000Y - 0.344U - 0.714V
     * B = 1.000Y + 1.772U
     */

    *r = (1000 * Y + 1402 * Cr) / 1000;
    *g = (1000 * Y -  344 * Cb - 714 * Cr) / 1000;
    *b = (1000 * Y + 1772 * Cb) / 1000;

    if( *r < 0 || *g < 0 || *b < 0 || *r > 255 || *g > 255 || *b > 255 ){
	if( opt_v )
	    fprintf(stderr, "pixcel(%d,%d): Y=%d Cb=%d Cr=%d rgb=(%d,%d,%d)\n",
		    n % opt_W, n / opt_W, Y, Cb, Cr, *r, *g, *b);
	if( *r < 0 )
	    *r = 0;
	if( *r > 255 )
	    *r = 255;
	if( *g < 0 )
	    *g = 0;
	if( *g > 255 )
	    *g = 255;
	if( *b < 0 )
	    *b = 0;
	if( *b > 255 )
	    *b = 255;
    }
}

#define max(a,b)	((a)>(b)?(a):(b))
#define min(a,b)	((a)<(b)?(a):(b))

int main(int argc, char **argv)
{
    int len;
    int p, retval, Y0, Y1, Cb, Cr, r, g, b;
    unsigned char *d;
    int bufn, bufp;
#ifdef SHOW_MAXMIN
    int Y_max, Y_min, Cb_max, Cb_min, Cr_max, Cr_min;
#endif
    int opt,n;

    while( (opt=getopt(argc, argv, "vsiW:H:")) != -1 ){
	switch(opt){
	case 'i':
	    opt_i = 1;
	    break;
	case 'v':
	    opt_v = 1;
	    break;
	case 'W':
	    n = atoi(optarg);
	    if( 0 < n && n <= FW )
		opt_W = n;
	    else{
		fprintf(stderr, "invalid argument -W %s\n", optarg);
	    }
	    break;
	case 'H':
	    n = atoi(optarg);
	    if( 0 < n && n <= FH )
		opt_H = n;
	    else{
		fprintf(stderr, "invalid argument -H %s\n", optarg);
	    }
	    break;
	default:
	    fprintf(stderr, "unknown option %c(0x%02x)\n", opt, opt);
	}
    }

    p = 0;

    printf("P3\n");
    printf("# CREATOR: yuv2ppm\n");
    printf("%d %d\n", opt_W, opt_H);
    printf("255");

    bufn = fread(yuvbuf, 4, PIXCEL_NUM/2, stdin);
    if( bufn == -1 ){
	fprintf(stderr, "yuv2ppm fread: error .. return %d (errno=%d)\n",
		retval, errno);
	return 1;
    }

    bufp = 0;
    while( bufp < bufn ){
	d = yuvbuf + bufp++ * 4;
	if( p > PIXCEL_NUM ){
	    fprintf(stderr, "input file over %d\n", PIXCEL_NUM);
	    break;
	}
#ifdef SHOW_MAXMIN
	if( p == 0 ){
	    Y_max = Y_min = d[0];
	    Cb_max = Cb_min = d[1];
	    Cr_max = Cr_min = d[3];
	    Y_max = max(Y_max, d[2]);
	    Y_min = min(Y_min, d[2]);
	}else{
	    Y_max = max(Y_max, d[0]);
	    Y_min = min(Y_min, d[0]);
	    Cb_max = max(Cb_max, d[1]);
	    Cb_min = min(Cb_min, d[1]);
	    Y_max = max(Y_max, d[2]);
	    Y_min = min(Y_min, d[2]);
	    Cr_max = max(Cr_max, d[3]);
	    Cr_min = min(Cr_min, d[3]);
	}
#endif

	Y0 = d[0];
	Cb = d[1];
	Y1 = d[2];
	Cr = d[3];
#if 0
#if 1
	Cb = ((d[1]-128) * 3) >> 1;	/* fix me */
	Cr = ((d[3]-128) * 3) >> 1;	/* fix me */
#else
	Cb = d[1]-128;
	Cr = d[3]-128;
#endif
#endif
	YCbCr2RGB_8fs(p, Y0, Cb, Cr, &r, &g, &b);
	pixcel_to_buffer(p++, r, g, b);
	YCbCr2RGB_8fs(p, Y1, Cb, Cr, &r, &g, &b);
	pixcel_to_buffer(p++, r, g, b);
    }

    while( p < PIXCEL_NUM ){
	pixcel_to_buffer(p++, 30, 10, 10);
    }

    pixcel_write();

    printf("\n");
#ifdef SHOW_MAXMIN
    if( opt_v )
	fprintf(stderr, "Y = (%d - %d), Cb = (%d - %d), Cr = (%d - %d)\n",
		Y_min, Y_max, Cb_min, Cb_max, Cr_min, Cr_max);
#endif

    return 0;
}