9222    int              do_background;  member
9237     int do_background, const png_color_16 *pointer_to_the_background_color,  in gamma_display_init()  argument
9254    dp->do_background = do_background;  in gamma_display_init()
9255    if (do_background && pointer_to_the_background_color != 0)  in gamma_display_init()
9294    if (dp->do_background >= ALPHA_MODE_OFFSET)  in gamma_info_imp()
9299          int mode = dp->do_background - ALPHA_MODE_OFFSET;  in gamma_info_imp()
9348       if (dp->do_background)  in gamma_info_imp()
9359             png_set_background(pp, &dp->background_color, dp->do_background,  in gamma_info_imp()
9363                dp->do_background, 0/*need_expand*/, g);  in gamma_info_imp()
9400    int do_background;  member
9472       vi->do_background = dp->do_background;  in init_validate_info()
9474       if (vi->do_background != 0)  in init_validate_info()
9501       vi->do_background = 0;  in init_validate_info()
9503    if (vi->do_background == 0)  in init_validate_info()
9523 gamma_component_compose(int do_background, double input_sample, double alpha,  in gamma_component_compose()  argument
9526    switch (do_background)  in gamma_component_compose()
9598    const int do_background = vi->do_background;  in gamma_component_validate()  local
9612    if (alpha == 1 /* opaque pixel component */ || !do_background  in gamma_component_validate()
9614       || do_background == ALPHA_MODE_OFFSET + PNG_ALPHA_PNG  in gamma_component_validate()
9618       && do_background != ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN  in gamma_component_validate()
9674          input_sample = gamma_component_compose(do_background, input_sample,  in gamma_component_validate()
9692          if (do_background != ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN)  in gamma_component_validate()
9706          if (do_background == ALPHA_MODE_OFFSET + PNG_ALPHA_OPTIMIZED &&  in gamma_component_validate()
9878             tmp = gamma_component_compose(do_background, tmp, alpha, background,  in gamma_component_validate()
9897             tmp = gamma_component_compose(do_background, tmp, alpha, background,  in gamma_component_validate()
9990             switch (do_background)  in gamma_component_validate()
10231       || in_bd != out_bd || in_ct != out_ct || vi.do_background;  in gamma_image_validate()
10232    process_tRNS = dp->this.has_tRNS && vi.do_background;  in gamma_image_validate()
10775    const int use_input_precision, const int do_background,  in gamma_composition_test()  argument
10785    switch (do_background)  in gamma_composition_test()
10847          if (expand_16 && (do_background == PNG_BACKGROUND_GAMMA_UNIQUE ||  in gamma_composition_test()
10848                            do_background == PNG_BACKGROUND_GAMMA_FILE) &&  in gamma_composition_test()
10897    if (do_background < ALPHA_MODE_OFFSET)  in gamma_composition_test()
10919       0/*strip 16*/, expand_16, do_background, &background, bg);  in gamma_composition_test()
10924 perform_gamma_composition_tests(png_modifier *pm, int do_background,  in perform_gamma_composition_tests()  argument
10953             pm->use_input_precision, do_background, expand_16);  in perform_gamma_composition_tests()
11129       int do_background;  in perform_gamma_test()  local
11138       for (do_background = ALPHA_MODE_OFFSET + PNG_ALPHA_STANDARD;  in perform_gamma_test()
11139          do_background <= ALPHA_MODE_OFFSET + PNG_ALPHA_BROKEN && !fail(pm);  in perform_gamma_test()
11140          ++do_background)  in perform_gamma_test()
11141          perform_gamma_composition_tests(pm, do_background,  in perform_gamma_test()