shithub: treason

ref: 27154e7406931d7e676dbf6267865c87e3b6dfbe
dir: /yuv.c/

#include <u.h>

void yuv420_rgb24(
	u32int width, u32int height,
	const u8int *Y, const u8int *U, const u8int *V, u32int Y_stride, u32int UV_stride,
	u8int *RGB, u32int RGB_stride)
{
	u32int x, y;
	int yy1, cb1, cr1;
	int r, g, b, go;

	for(y = 0; y < height-1; y += 2){
		for(x = 0; x < width-1; x += 2){
			cb1 = (int)*U - 0x80;
			cr1 = (int)*V - 0x80;
			go = 22554*cb1 - 46802*cr1;

#define ONE do{ \
			yy1 = (int)*Y * 0x10101; \
			r = yy1 + 91881*cr1; \
			r = (r & 0xff000000) ? ~(r >> 31) : (r>>16); \
			g = yy1 - go; \
			g = (g & 0xff000000) ? ~(g >> 31) : (g>>16); \
			b = yy1 + 116130*cb1; \
			b = (b & 0xff000000) ? ~(b >> 31) : (b>>16); \
			RGB[2] = r; \
			RGB[1] = g; \
			RGB[0] = b; \
}while(0)

			ONE; Y += 1;        RGB += 3;
			ONE; Y += Y_stride; RGB += RGB_stride;
			ONE; Y -= 1;        RGB -= 3;
			ONE; Y -= Y_stride; RGB -= RGB_stride;

			Y += 2;
			U += 1;
			V += 1;

			RGB += 6;
		}

		Y += 2*Y_stride - x;
		U += UV_stride - x/2;
		V += UV_stride - x/2;
		RGB += 2*RGB_stride - 3*x;
	}
}