diff --git a/test/reference/clip-operator.traps.argb32.ref.png b/test/reference/clip-operator.traps.argb32.ref.png index 1a562cdd0..a4179d221 100644 Binary files a/test/reference/clip-operator.traps.argb32.ref.png and b/test/reference/clip-operator.traps.argb32.ref.png differ diff --git a/test/reference/clip-operator.traps.rgb24.ref.png b/test/reference/clip-operator.traps.rgb24.ref.png index 893350532..f35c9d5d9 100644 Binary files a/test/reference/clip-operator.traps.rgb24.ref.png and b/test/reference/clip-operator.traps.rgb24.ref.png differ diff --git a/test/reference/clip-text.traps.argb32.ref.png b/test/reference/clip-text.traps.argb32.ref.png index eed421f35..2a682981c 100644 Binary files a/test/reference/clip-text.traps.argb32.ref.png and b/test/reference/clip-text.traps.argb32.ref.png differ diff --git a/test/reference/clip-text.traps.rgb24.ref.png b/test/reference/clip-text.traps.rgb24.ref.png index eed421f35..2a682981c 100644 Binary files a/test/reference/clip-text.traps.rgb24.ref.png and b/test/reference/clip-text.traps.rgb24.ref.png differ diff --git a/test/reference/font-matrix-translation.traps.argb32.ref.png b/test/reference/font-matrix-translation.traps.argb32.ref.png deleted file mode 100644 index dd5fabacd..000000000 Binary files a/test/reference/font-matrix-translation.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/font-matrix-translation.traps.ref.png b/test/reference/font-matrix-translation.traps.ref.png new file mode 100644 index 000000000..a4a108206 Binary files /dev/null and b/test/reference/font-matrix-translation.traps.ref.png differ diff --git a/test/reference/font-matrix-translation.traps.rgb24.ref.png b/test/reference/font-matrix-translation.traps.rgb24.ref.png deleted file mode 100644 index dd5fabacd..000000000 Binary files a/test/reference/font-matrix-translation.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/ft-show-glyphs-positioning.traps.argb32.ref.png b/test/reference/ft-show-glyphs-positioning.traps.argb32.ref.png deleted file mode 100644 index b49ed47ca..000000000 Binary files a/test/reference/ft-show-glyphs-positioning.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/ft-show-glyphs-positioning.traps.ref.png b/test/reference/ft-show-glyphs-positioning.traps.ref.png new file mode 100644 index 000000000..af6dcaf95 Binary files /dev/null and b/test/reference/ft-show-glyphs-positioning.traps.ref.png differ diff --git a/test/reference/ft-show-glyphs-positioning.traps.rgb24.ref.png b/test/reference/ft-show-glyphs-positioning.traps.rgb24.ref.png deleted file mode 100644 index b49ed47ca..000000000 Binary files a/test/reference/ft-show-glyphs-positioning.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/ft-show-glyphs-table.traps.argb32.ref.png b/test/reference/ft-show-glyphs-table.traps.argb32.ref.png deleted file mode 100644 index c762dc749..000000000 Binary files a/test/reference/ft-show-glyphs-table.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/ft-show-glyphs-table.traps.ref.png b/test/reference/ft-show-glyphs-table.traps.ref.png new file mode 100644 index 000000000..ed6912489 Binary files /dev/null and b/test/reference/ft-show-glyphs-table.traps.ref.png differ diff --git a/test/reference/ft-show-glyphs-table.traps.rgb24.ref.png b/test/reference/ft-show-glyphs-table.traps.rgb24.ref.png deleted file mode 100644 index c762dc749..000000000 Binary files a/test/reference/ft-show-glyphs-table.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/glyph-cache-pressure.traps.argb32.ref.png b/test/reference/glyph-cache-pressure.traps.argb32.ref.png deleted file mode 100644 index 14182f11d..000000000 Binary files a/test/reference/glyph-cache-pressure.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/glyph-cache-pressure.traps.ref.png b/test/reference/glyph-cache-pressure.traps.ref.png new file mode 100644 index 000000000..a6e1b061f Binary files /dev/null and b/test/reference/glyph-cache-pressure.traps.ref.png differ diff --git a/test/reference/glyph-cache-pressure.traps.rgb24.ref.png b/test/reference/glyph-cache-pressure.traps.rgb24.ref.png deleted file mode 100644 index 14182f11d..000000000 Binary files a/test/reference/glyph-cache-pressure.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/halo-transform.traps.argb32.ref.png b/test/reference/halo-transform.traps.argb32.ref.png deleted file mode 100644 index ac314b0ef..000000000 Binary files a/test/reference/halo-transform.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/halo-transform.traps.ref.png b/test/reference/halo-transform.traps.ref.png new file mode 100644 index 000000000..45cb90ff0 Binary files /dev/null and b/test/reference/halo-transform.traps.ref.png differ diff --git a/test/reference/halo-transform.traps.rgb24.ref.png b/test/reference/halo-transform.traps.rgb24.ref.png deleted file mode 100644 index ac314b0ef..000000000 Binary files a/test/reference/halo-transform.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/halo.traps.argb32.ref.png b/test/reference/halo.traps.argb32.ref.png deleted file mode 100644 index bc971d809..000000000 Binary files a/test/reference/halo.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/halo.traps.ref.png b/test/reference/halo.traps.ref.png new file mode 100644 index 000000000..c915a242b Binary files /dev/null and b/test/reference/halo.traps.ref.png differ diff --git a/test/reference/halo.traps.rgb24.ref.png b/test/reference/halo.traps.rgb24.ref.png deleted file mode 100644 index bc971d809..000000000 Binary files a/test/reference/halo.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/inverse-text.base.argb32.ref.png b/test/reference/inverse-text.base.argb32.ref.png deleted file mode 100644 index 40defe6e1..000000000 Binary files a/test/reference/inverse-text.base.argb32.ref.png and /dev/null differ diff --git a/test/reference/inverse-text.base.rgb24.ref.png b/test/reference/inverse-text.base.rgb24.ref.png deleted file mode 100644 index 40defe6e1..000000000 Binary files a/test/reference/inverse-text.base.rgb24.ref.png and /dev/null differ diff --git a/test/reference/inverse-text.image16.ref.png b/test/reference/inverse-text.image16.ref.png deleted file mode 100644 index a24266d66..000000000 Binary files a/test/reference/inverse-text.image16.ref.png and /dev/null differ diff --git a/test/reference/inverse-text.ps.ref.png b/test/reference/inverse-text.ps.ref.png deleted file mode 100644 index 6043684b2..000000000 Binary files a/test/reference/inverse-text.ps.ref.png and /dev/null differ diff --git a/test/reference/inverse-text.quartz.ref.png b/test/reference/inverse-text.quartz.ref.png deleted file mode 100644 index df0ea57ea..000000000 Binary files a/test/reference/inverse-text.quartz.ref.png and /dev/null differ diff --git a/test/reference/inverse-text.ref.png b/test/reference/inverse-text.ref.png deleted file mode 100644 index 40defe6e1..000000000 Binary files a/test/reference/inverse-text.ref.png and /dev/null differ diff --git a/test/reference/inverse-text.traps.argb32.ref.png b/test/reference/inverse-text.traps.argb32.ref.png deleted file mode 100644 index 40defe6e1..000000000 Binary files a/test/reference/inverse-text.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/inverse-text.traps.ref.png b/test/reference/inverse-text.traps.ref.png new file mode 100644 index 000000000..b7bbb972f Binary files /dev/null and b/test/reference/inverse-text.traps.ref.png differ diff --git a/test/reference/inverse-text.traps.rgb24.ref.png b/test/reference/inverse-text.traps.rgb24.ref.png deleted file mode 100644 index 40defe6e1..000000000 Binary files a/test/reference/inverse-text.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/operator-clear.traps.argb32.ref.png b/test/reference/operator-clear.traps.argb32.ref.png index 235db6b43..c49b4a8d6 100644 Binary files a/test/reference/operator-clear.traps.argb32.ref.png and b/test/reference/operator-clear.traps.argb32.ref.png differ diff --git a/test/reference/operator-clear.traps.rgb24.ref.png b/test/reference/operator-clear.traps.rgb24.ref.png index fa07d4a52..51d38d134 100644 Binary files a/test/reference/operator-clear.traps.rgb24.ref.png and b/test/reference/operator-clear.traps.rgb24.ref.png differ diff --git a/test/reference/operator-source.traps.argb32.ref.png b/test/reference/operator-source.traps.argb32.ref.png index 6884f3353..42e24f24c 100644 Binary files a/test/reference/operator-source.traps.argb32.ref.png and b/test/reference/operator-source.traps.argb32.ref.png differ diff --git a/test/reference/operator-source.traps.rgb24.ref.png b/test/reference/operator-source.traps.rgb24.ref.png index 32a6a401b..4736d5852 100644 Binary files a/test/reference/operator-source.traps.rgb24.ref.png and b/test/reference/operator-source.traps.rgb24.ref.png differ diff --git a/test/reference/partial-clip-text-right.traps.argb32.ref.png b/test/reference/partial-clip-text-right.traps.argb32.ref.png deleted file mode 100644 index 3e69ca9e0..000000000 Binary files a/test/reference/partial-clip-text-right.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/partial-clip-text-right.traps.ref.png b/test/reference/partial-clip-text-right.traps.ref.png new file mode 100644 index 000000000..2fbdca038 Binary files /dev/null and b/test/reference/partial-clip-text-right.traps.ref.png differ diff --git a/test/reference/partial-clip-text-right.traps.rgb24.ref.png b/test/reference/partial-clip-text-right.traps.rgb24.ref.png deleted file mode 100644 index 3e69ca9e0..000000000 Binary files a/test/reference/partial-clip-text-right.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/partial-clip-text-top.traps.argb32.ref.png b/test/reference/partial-clip-text-top.traps.argb32.ref.png deleted file mode 100644 index afe2d3efe..000000000 Binary files a/test/reference/partial-clip-text-top.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/partial-clip-text-top.traps.ref.png b/test/reference/partial-clip-text-top.traps.ref.png new file mode 100644 index 000000000..d18475be3 Binary files /dev/null and b/test/reference/partial-clip-text-top.traps.ref.png differ diff --git a/test/reference/partial-clip-text-top.traps.rgb24.ref.png b/test/reference/partial-clip-text-top.traps.rgb24.ref.png deleted file mode 100644 index afe2d3efe..000000000 Binary files a/test/reference/partial-clip-text-top.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/pthread-show-text.traps.argb32.ref.png b/test/reference/pthread-show-text.traps.argb32.ref.png deleted file mode 100644 index efa5fe9af..000000000 Binary files a/test/reference/pthread-show-text.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/pthread-show-text.traps.ref.png b/test/reference/pthread-show-text.traps.ref.png new file mode 100644 index 000000000..90d0af349 Binary files /dev/null and b/test/reference/pthread-show-text.traps.ref.png differ diff --git a/test/reference/pthread-show-text.traps.rgb24.ref.png b/test/reference/pthread-show-text.traps.rgb24.ref.png deleted file mode 100644 index efa5fe9af..000000000 Binary files a/test/reference/pthread-show-text.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/radial-gradient-mask-source.traps.rgb24.ref.png b/test/reference/radial-gradient-mask-source.traps.rgb24.ref.png index 5748d8207..55335196a 100644 Binary files a/test/reference/radial-gradient-mask-source.traps.rgb24.ref.png and b/test/reference/radial-gradient-mask-source.traps.rgb24.ref.png differ diff --git a/test/reference/select-font-face.traps.argb32.ref.png b/test/reference/select-font-face.traps.argb32.ref.png deleted file mode 100644 index be89d714f..000000000 Binary files a/test/reference/select-font-face.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/select-font-face.traps.ref.png b/test/reference/select-font-face.traps.ref.png new file mode 100644 index 000000000..1334a9a01 Binary files /dev/null and b/test/reference/select-font-face.traps.ref.png differ diff --git a/test/reference/select-font-face.traps.rgb24.ref.png b/test/reference/select-font-face.traps.rgb24.ref.png deleted file mode 100644 index be89d714f..000000000 Binary files a/test/reference/select-font-face.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/show-glyphs-advance.traps.argb32.ref.png b/test/reference/show-glyphs-advance.traps.argb32.ref.png deleted file mode 100644 index e78409922..000000000 Binary files a/test/reference/show-glyphs-advance.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/show-glyphs-advance.traps.ref.png b/test/reference/show-glyphs-advance.traps.ref.png new file mode 100644 index 000000000..e65ad05d5 Binary files /dev/null and b/test/reference/show-glyphs-advance.traps.ref.png differ diff --git a/test/reference/show-glyphs-advance.traps.rgb24.ref.png b/test/reference/show-glyphs-advance.traps.rgb24.ref.png deleted file mode 100644 index e78409922..000000000 Binary files a/test/reference/show-glyphs-advance.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/show-text-current-point.traps.argb32.ref.png b/test/reference/show-text-current-point.traps.argb32.ref.png deleted file mode 100644 index b2ee5b2e4..000000000 Binary files a/test/reference/show-text-current-point.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/show-text-current-point.traps.ref.png b/test/reference/show-text-current-point.traps.ref.png new file mode 100644 index 000000000..d60d4ac01 Binary files /dev/null and b/test/reference/show-text-current-point.traps.ref.png differ diff --git a/test/reference/show-text-current-point.traps.rgb24.ref.png b/test/reference/show-text-current-point.traps.rgb24.ref.png deleted file mode 100644 index b2ee5b2e4..000000000 Binary files a/test/reference/show-text-current-point.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/smask-text.traps.argb32.ref.png b/test/reference/smask-text.traps.argb32.ref.png deleted file mode 100644 index c57025944..000000000 Binary files a/test/reference/smask-text.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/smask-text.traps.ref.png b/test/reference/smask-text.traps.ref.png new file mode 100644 index 000000000..66ef289ca Binary files /dev/null and b/test/reference/smask-text.traps.ref.png differ diff --git a/test/reference/smask-text.traps.rgb24.ref.png b/test/reference/smask-text.traps.rgb24.ref.png deleted file mode 100644 index c57025944..000000000 Binary files a/test/reference/smask-text.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/smask.traps.argb32.ref.png b/test/reference/smask.traps.argb32.ref.png deleted file mode 100644 index 445d9202d..000000000 Binary files a/test/reference/smask.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/smask.traps.ref.png b/test/reference/smask.traps.ref.png new file mode 100644 index 000000000..357e8e7fb Binary files /dev/null and b/test/reference/smask.traps.ref.png differ diff --git a/test/reference/smask.traps.rgb24.ref.png b/test/reference/smask.traps.rgb24.ref.png deleted file mode 100644 index 445d9202d..000000000 Binary files a/test/reference/smask.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/stroke-pattern.traps.ref.png b/test/reference/stroke-pattern.traps.ref.png new file mode 100644 index 000000000..67bb03143 Binary files /dev/null and b/test/reference/stroke-pattern.traps.ref.png differ diff --git a/test/reference/text-antialias-gray.traps.argb32.ref.png b/test/reference/text-antialias-gray.traps.argb32.ref.png deleted file mode 100644 index b1dbc20b7..000000000 Binary files a/test/reference/text-antialias-gray.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/text-antialias-gray.traps.ref.png b/test/reference/text-antialias-gray.traps.ref.png new file mode 100644 index 000000000..06b805eaa Binary files /dev/null and b/test/reference/text-antialias-gray.traps.ref.png differ diff --git a/test/reference/text-antialias-gray.traps.rgb24.ref.png b/test/reference/text-antialias-gray.traps.rgb24.ref.png deleted file mode 100644 index b1dbc20b7..000000000 Binary files a/test/reference/text-antialias-gray.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/text-antialias-none.traps.argb32.ref.png b/test/reference/text-antialias-none.traps.ref.png similarity index 100% rename from test/reference/text-antialias-none.traps.argb32.ref.png rename to test/reference/text-antialias-none.traps.ref.png diff --git a/test/reference/text-antialias-none.traps.rgb24.ref.png b/test/reference/text-antialias-none.traps.rgb24.ref.png deleted file mode 100644 index 86c09cd36..000000000 Binary files a/test/reference/text-antialias-none.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/text-antialias-subpixel-bgr.traps.ref.png b/test/reference/text-antialias-subpixel-bgr.traps.ref.png new file mode 100644 index 000000000..a221472df Binary files /dev/null and b/test/reference/text-antialias-subpixel-bgr.traps.ref.png differ diff --git a/test/reference/text-antialias-subpixel-rgb.traps.ref.png b/test/reference/text-antialias-subpixel-rgb.traps.ref.png new file mode 100644 index 000000000..af5e0aef5 Binary files /dev/null and b/test/reference/text-antialias-subpixel-rgb.traps.ref.png differ diff --git a/test/reference/text-antialias-subpixel-vbgr.traps.ref.png b/test/reference/text-antialias-subpixel-vbgr.traps.ref.png new file mode 100644 index 000000000..905579b66 Binary files /dev/null and b/test/reference/text-antialias-subpixel-vbgr.traps.ref.png differ diff --git a/test/reference/text-antialias-subpixel-vrgb.traps.ref.png b/test/reference/text-antialias-subpixel-vrgb.traps.ref.png new file mode 100644 index 000000000..f7c5befa9 Binary files /dev/null and b/test/reference/text-antialias-subpixel-vrgb.traps.ref.png differ diff --git a/test/reference/text-antialias-subpixel.traps.argb32.ref.png b/test/reference/text-antialias-subpixel.traps.argb32.ref.png deleted file mode 100644 index 09da5fae2..000000000 Binary files a/test/reference/text-antialias-subpixel.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/text-antialias-subpixel.traps.ref.png b/test/reference/text-antialias-subpixel.traps.ref.png new file mode 100644 index 000000000..af5e0aef5 Binary files /dev/null and b/test/reference/text-antialias-subpixel.traps.ref.png differ diff --git a/test/reference/text-antialias-subpixel.traps.rgb24.ref.png b/test/reference/text-antialias-subpixel.traps.rgb24.ref.png deleted file mode 100644 index 09da5fae2..000000000 Binary files a/test/reference/text-antialias-subpixel.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/text-glyph-range.traps.argb32.ref.png b/test/reference/text-glyph-range.traps.argb32.ref.png deleted file mode 100644 index 91de73d5f..000000000 Binary files a/test/reference/text-glyph-range.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/text-glyph-range.traps.ref.png b/test/reference/text-glyph-range.traps.ref.png new file mode 100644 index 000000000..326869923 Binary files /dev/null and b/test/reference/text-glyph-range.traps.ref.png differ diff --git a/test/reference/text-glyph-range.traps.rgb24.ref.png b/test/reference/text-glyph-range.traps.rgb24.ref.png deleted file mode 100644 index 91de73d5f..000000000 Binary files a/test/reference/text-glyph-range.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/text-pattern.traps.argb32.ref.png b/test/reference/text-pattern.traps.argb32.ref.png index d9f3eaab7..79f18e4e1 100644 Binary files a/test/reference/text-pattern.traps.argb32.ref.png and b/test/reference/text-pattern.traps.argb32.ref.png differ diff --git a/test/reference/text-pattern.traps.rgb24.ref.png b/test/reference/text-pattern.traps.rgb24.ref.png index 70d4a5945..b073b9831 100644 Binary files a/test/reference/text-pattern.traps.rgb24.ref.png and b/test/reference/text-pattern.traps.rgb24.ref.png differ diff --git a/test/reference/text-rotate.traps.argb32.ref.png b/test/reference/text-rotate.traps.argb32.ref.png deleted file mode 100644 index 1db9a00d8..000000000 Binary files a/test/reference/text-rotate.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/text-rotate.traps.ref.png b/test/reference/text-rotate.traps.ref.png new file mode 100644 index 000000000..ff3fe847c Binary files /dev/null and b/test/reference/text-rotate.traps.ref.png differ diff --git a/test/reference/text-rotate.traps.rgb24.ref.png b/test/reference/text-rotate.traps.rgb24.ref.png deleted file mode 100644 index 1db9a00d8..000000000 Binary files a/test/reference/text-rotate.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/unbounded-operator.traps.argb32.ref.png b/test/reference/unbounded-operator.traps.argb32.ref.png index 80a57b5e1..fde0b6e86 100644 Binary files a/test/reference/unbounded-operator.traps.argb32.ref.png and b/test/reference/unbounded-operator.traps.argb32.ref.png differ diff --git a/test/reference/unbounded-operator.traps.rgb24.ref.png b/test/reference/unbounded-operator.traps.rgb24.ref.png index 1c0276c4f..8d51cce5d 100644 Binary files a/test/reference/unbounded-operator.traps.rgb24.ref.png and b/test/reference/unbounded-operator.traps.rgb24.ref.png differ diff --git a/test/reference/user-font-proxy.traps.argb32.ref.png b/test/reference/user-font-proxy.traps.argb32.ref.png deleted file mode 100644 index 92ce63617..000000000 Binary files a/test/reference/user-font-proxy.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/user-font-proxy.traps.ref.png b/test/reference/user-font-proxy.traps.ref.png new file mode 100644 index 000000000..094938c6e Binary files /dev/null and b/test/reference/user-font-proxy.traps.ref.png differ diff --git a/test/reference/user-font-proxy.traps.rgb24.ref.png b/test/reference/user-font-proxy.traps.rgb24.ref.png deleted file mode 100644 index 92ce63617..000000000 Binary files a/test/reference/user-font-proxy.traps.rgb24.ref.png and /dev/null differ diff --git a/test/reference/user-font-rescale.traps.argb32.ref.png b/test/reference/user-font-rescale.traps.argb32.ref.png deleted file mode 100644 index c644f751a..000000000 Binary files a/test/reference/user-font-rescale.traps.argb32.ref.png and /dev/null differ diff --git a/test/reference/user-font-rescale.traps.ref.png b/test/reference/user-font-rescale.traps.ref.png new file mode 100644 index 000000000..093906014 Binary files /dev/null and b/test/reference/user-font-rescale.traps.ref.png differ diff --git a/test/reference/user-font-rescale.traps.rgb24.ref.png b/test/reference/user-font-rescale.traps.rgb24.ref.png deleted file mode 100644 index c644f751a..000000000 Binary files a/test/reference/user-font-rescale.traps.rgb24.ref.png and /dev/null differ