gamma_component_compose 8161 contrib/libtests/pngvalid.c          input_sample = gamma_component_compose(do_background, input_sample,
gamma_component_compose 8365 contrib/libtests/pngvalid.c             tmp = gamma_component_compose(do_background, tmp, alpha, background,
gamma_component_compose 8384 contrib/libtests/pngvalid.c             tmp = gamma_component_compose(do_background, tmp, alpha, background,