SUM1              759 third_party/libwebp/enc/picture.c         RGB_TO_UV(x, y, SUM1);
SUM1              771 third_party/libwebp/enc/picture.c           RGB_TO_UV0(2 * x, x, y, SUM1);
SUM1              777 third_party/libwebp/enc/picture.c           RGB_TO_UV0(x, x, y, SUM1);