VP8RGBToY 480 third_party/libwebp/dec/vp8l.c y[i] = VP8RGBToY((p >> 16) & 0xff, (p >> 8) & 0xff, (p >> 0) & 0xff, VP8RGBToY 594 third_party/libwebp/enc/picture.c return VP8RGBToY(r, g, b, VP8RandomBits(rg, YUV_FIX));