#include #include #include static LONGLONG mpeg3_MMX_601_Y_COEF = 0x0000004000400040; inline void mpeg3_601_mmx(unsigned long y, unsigned long *output) { asm(" /* Output will be 0x00rrggbb */ movd (%0), %%mm0; /* Load y 0x00000000000000yy */ /* pmullw mpeg3_MMX_601_Y_COEF, %%mm0; // Scale y 0x00000000000000yy */ psllw $6, %%mm0; /* Shift y coeffs 0x0000yyy0yyy0yyy0 */ movd %%mm0, (%1); /* Store output */ " : : "r" (&y), "r" (output)); } int main(int argc, char *argv[]) { unsigned char output[1024]; memset(output, 0, 1024); mpeg3_601_mmx(1, (unsigned long*)output); printf("%02x%02x\n", *(unsigned char*)&output[1], *(unsigned char*)&output[0]); }