Faster RGB to YUV conversion

Original commit message from CVS:
Faster RGB to YUV conversion
This commit is contained in:
Wim Taymans 2002-02-02 16:21:41 +00:00
parent 5d8ebbc9f5
commit c7669b9434

View file

@ -12,139 +12,69 @@
#include <gst/gst.h>
#define RGB2YUV_SHIFT 8
#define BY ((int)( 0.098*(1<<RGB2YUV_SHIFT)+0.5))
#define BV ((int)(-0.071*(1<<RGB2YUV_SHIFT)+0.5))
#define BU ((int)( 0.439*(1<<RGB2YUV_SHIFT)+0.5))
#define GY ((int)( 0.504*(1<<RGB2YUV_SHIFT)+0.5))
#define GV ((int)(-0.368*(1<<RGB2YUV_SHIFT)+0.5))
#define GU ((int)(-0.291*(1<<RGB2YUV_SHIFT)+0.5))
#define RY ((int)( 0.257*(1<<RGB2YUV_SHIFT)+0.5))
#define RV ((int)( 0.439*(1<<RGB2YUV_SHIFT)+0.5))
#define RU ((int)(-0.148*(1<<RGB2YUV_SHIFT)+0.5))
#define Y_FROM_RGB(r,g,b) ((9798 * (r) + 19235 * (g) + 3736 * (b)) >> 15)
#define U_FROM_BY(b,y) ((16122 * ((b) - (y))) >> 15) + 128;
#define V_FROM_RY(r,y) ((25203 * ((r) - (y))) >> 15) + 128;
/**
*
* height should be a multiple of 2 and width should be a multiple of 2 (if this is a
* problem for anyone then tell me, and ill fix it)
* chrominance data is only taken from every secound line others are ignored FIXME write HQ version
*/
void
gst_colorspace_rgb32_to_i420 (unsigned char *src, unsigned char *dest, guint width, guint height)
static void
gst_colorspace_rgb32_to_yuv (unsigned char *src,
unsigned char *ydst,
unsigned char *udst,
unsigned char *vdst,
guint width, guint height)
{
int y;
const int chrom_width = width >> 1;
const int chrom_size = (width * height) >> 2;
int Y;
int b, g, r;
unsigned char *ydst = dest;
unsigned char *udst = ydst + (width * height);
unsigned char *vdst = udst + chrom_size;
for (y = 0; y < height; y += 2) {
for (y = height; y; y -= 2) {
int i;
for (i = 0; i < chrom_width; i++) {
unsigned int b = src[8 * i + 0];
unsigned int g = src[8 * i + 1];
unsigned int r = src[8 * i + 2];
for (i = chrom_width; i; i--) {
b = *src++;
g = *src++;
r = *src++;
src++;
unsigned int Y = ((RY * r + GY * g + BY * b) >> RGB2YUV_SHIFT) + 16;
unsigned int V = ((RV * r + GV * g + BV * b) >> RGB2YUV_SHIFT) + 128;
unsigned int U = ((RU * r + GU * g + BU * b) >> RGB2YUV_SHIFT) + 128;
Y = Y_FROM_RGB (r,g,b);
udst[i] = U;
vdst[i] = V;
ydst[2 * i] = Y;
*ydst++ = Y;
*udst++ = U_FROM_BY (b,Y);
*vdst++ = V_FROM_RY (r,Y);
b = src[8 * i + 4];
g = src[8 * i + 5];
r = src[8 * i + 6];
b = *src++;
g = *src++;
r = *src++; src++;
Y = ((RY * r + GY * g + BY * b) >> RGB2YUV_SHIFT) + 16;
ydst[2 * i + 1] = Y;
*ydst++ = Y_FROM_RGB (r,g,b);
}
ydst += width;
src += (width * 4);
for (i = 0; i < chrom_width; i++) {
unsigned int b = src[8 * i + 0];
unsigned int g = src[8 * i + 1];
unsigned int r = src[8 * i + 2];
unsigned int Y = ((RY * r + GY * g + BY * b) >> RGB2YUV_SHIFT) + 16;
ydst[2 * i] = Y;
b = src[8 * i + 4];
g = src[8 * i + 5];
r = src[8 * i + 6];
Y = ((RY * r + GY * g + BY * b) >> RGB2YUV_SHIFT) + 16;
ydst[2 * i + 1] = Y;
for (i = width; i; i--) {
b = *src++;
g = *src++;
r = *src++; src++;
*ydst++ = Y_FROM_RGB (r,g,b);
}
udst += chrom_width;
vdst += chrom_width;
ydst += width;
src += (width * 4);
}
}
void
gst_colorspace_rgb32_to_i420 (unsigned char *src, unsigned char *dest, guint width, guint height)
{
unsigned char *ydst = dest;
unsigned char *udst = ydst + (width * height);
unsigned char *vdst = udst + ((width * height) >> 2);
gst_colorspace_rgb32_to_yuv (src, ydst, udst, vdst, width, height);
}
void
gst_colorspace_rgb32_to_yv12 (unsigned char *src, unsigned char *dest, guint width, guint height)
{
int y;
const int chrom_width = width >> 1;
const int chrom_size = (width * height) >> 2;
unsigned char *ydst = dest;
unsigned char *vdst = ydst + (width * height);
unsigned char *udst = vdst + chrom_size;
unsigned char *udst = vdst + ((width * height) >> 2);
for (y = 0; y < height; y += 2) {
int i;
for (i = 0; i < chrom_width; i++) {
unsigned int b = src[8 * i + 0];
unsigned int g = src[8 * i + 1];
unsigned int r = src[8 * i + 2];
unsigned int Y = ((RY * r + GY * g + BY * b) >> RGB2YUV_SHIFT) + 16;
unsigned int V = ((RV * r + GV * g + BV * b) >> RGB2YUV_SHIFT) + 128;
unsigned int U = ((RU * r + GU * g + BU * b) >> RGB2YUV_SHIFT) + 128;
udst[i] = U;
vdst[i] = V;
ydst[2 * i] = Y;
b = src[8 * i + 4];
g = src[8 * i + 5];
r = src[8 * i + 6];
Y = ((RY * r + GY * g + BY * b) >> RGB2YUV_SHIFT) + 16;
ydst[2 * i + 1] = Y;
}
ydst += width;
src += (width * 4);
for (i = 0; i < chrom_width; i++) {
unsigned int b = src[8 * i + 0];
unsigned int g = src[8 * i + 1];
unsigned int r = src[8 * i + 2];
unsigned int Y = ((RY * r + GY * g + BY * b) >> RGB2YUV_SHIFT) + 16;
ydst[2 * i] = Y;
b = src[8 * i + 4];
g = src[8 * i + 5];
r = src[8 * i + 6];
Y = ((RY * r + GY * g + BY * b) >> RGB2YUV_SHIFT) + 16;
ydst[2 * i + 1] = Y;
}
udst += chrom_width;
vdst += chrom_width;
ydst += width;
src += (width * 4);
}
gst_colorspace_rgb32_to_yuv (src, ydst, udst, vdst, width, height);
}