Testing mask with image target (dev offset 0) 34 pixels differ (with maximum difference of 1) from reference image But perceptual diff finds no visually discernible difference. Accepting result. OUTPUT: output/mask.image.argb32.out.png TEST: mask TARGET: image FORMAT: argb32 OFFSET: 0 SIMILAR: 0 RESULT: PASS Testing mask with image target (dev offset 0) 433 pixels differ (with maximum difference of 6) from reference image But perceptual diff finds no visually discernible difference. Accepting result. OUTPUT: output/mask.image.rgb24.out.png TEST: mask TARGET: image FORMAT: rgb24 OFFSET: 0 SIMILAR: 0 RESULT: PASS