The background should be black, but it is transparent. This is probably a bug in the de-multiplying of alpha, see the openexr documentation Reproducible: Always
Ok, the bug happens because alpha==0 && color != 0 is a correct situation in EXR. See page 21 of: http://www.openexr.com/TechnicalIntroduction.pdf
Git commit 625faf4dff96934923afbeae427a9bf475cdf44d by Dmitry Kazakov. Committed on 04/04/2014 at 10:05. Pushed by dkazakov into branch 'master'. Fixed loading of the EXR files with zero alpha and non-zero colors EXR works with premultiplied colors, so it suports having zero alpha and non-zero colors. Krita doesn't support premultiplied colors, so we just set alpha to HALF_EPSILON on loading and reset it back to zero on saving. This introduces subtle round-trip bugs, but they happen for alpha < 0.01 values only (which is 1%). TODO: Now we also need to reset default projection color of the image to black to load the EXR properly M +1 -1 krita/plugins/formats/exr/CMakeLists.txt M +194 -90 krita/plugins/formats/exr/exr_converter.cc M +3 -5 krita/plugins/formats/exr/exr_converter.h M +1 -1 krita/plugins/formats/exr/exr_export.cc M +2 -1 krita/plugins/formats/exr/exr_import.cc A +- -- krita/plugins/formats/exr/tests/data/CandleGlass.exr M +57 -1 krita/plugins/formats/exr/tests/kis_exr_test.cpp M +1 -0 krita/plugins/formats/exr/tests/kis_exr_test.h M +39 -0 krita/sdk/tests/testutil.h http://commits.kde.org/calligra/625faf4dff96934923afbeae427a9bf475cdf44d
Git commit c20ee318b7c4f768fdcda6969c5861a87f67743a by Dmitry Kazakov. Committed on 04/04/2014 at 17:25. Pushed by dkazakov into branch 'master'. Added a Background Color feature to KisImage Now the user can choose the Background color for the projection. Just go to Image->Properties->Background Color and choose the one you want. And you'll never see the checkers anymore :) This also fixes EXR images, which should have a black BG color M +16 -10 krita/image/kis_group_layer.cc M +30 -0 krita/image/kis_image.cc M +11 -0 krita/image/kis_image.h M +3 -0 krita/plugins/formats/exr/exr_converter.cc M +23 -0 krita/ui/dialogs/kis_dlg_image_properties.cc M +4 -0 krita/ui/dialogs/kis_dlg_image_properties.h M +1 -7 krita/ui/forms/wdgcolorspaceselector.ui M +62 -32 krita/ui/forms/wdgimageproperties.ui M +11 -0 krita/ui/kra/kis_kra_loader.cpp M +10 -0 krita/ui/kra/kis_kra_saver.cpp M +1 -0 krita/ui/kra/kis_kra_saver.h M +5 -0 krita/ui/tests/kis_kra_saver_test.cpp http://commits.kde.org/calligra/c20ee318b7c4f768fdcda6969c5861a87f67743a
Git commit 5726aed45b0034f6425bd2659a0c10ef8e64fe62 by Dmitry Kazakov. Committed on 10/04/2014 at 11:52. Pushed by dkazakov into branch 'master'. Fix saving/loading of exr images with small alpha values There are several issues possible: 1) The image has zero alpha + non-zero color pixels. We artificially raise the alpha value to allow premultiplication. 2) The image has tiny non-zero alpha + non-zero color pixels, but division is possible without overflow of color channels. Then we must not change anything. 3) The image has tiny non-zero alpha + non-zero color pixels, but division is not possible due to a half overflow. In this case we must also raise alpha a bit (as in case 1) ) to allow correct rendering of the image. M +39 -38 krita/plugins/formats/exr/exr_converter.cc http://commits.kde.org/calligra/5726aed45b0034f6425bd2659a0c10ef8e64fe62
Git commit 6f54affba1f5b4005d451e1e46f2c7eb10e743f4 by Stuart Dickson, on behalf of Dmitry Kazakov. Committed on 04/04/2014 at 10:05. Pushed by dickson into tag 'steam-233896_233900'. Fixed loading of the EXR files with zero alpha and non-zero colors EXR works with premultiplied colors, so it suports having zero alpha and non-zero colors. Krita doesn't support premultiplied colors, so we just set alpha to HALF_EPSILON on loading and reset it back to zero on saving. This introduces subtle round-trip bugs, but they happen for alpha < 0.01 values only (which is 1%). TODO: Now we also need to reset default projection color of the image to black to load the EXR properly M +1 -1 krita/plugins/formats/exr/CMakeLists.txt M +194 -90 krita/plugins/formats/exr/exr_converter.cc M +3 -5 krita/plugins/formats/exr/exr_converter.h M +1 -1 krita/plugins/formats/exr/exr_export.cc M +2 -1 krita/plugins/formats/exr/exr_import.cc A +- -- krita/plugins/formats/exr/tests/data/CandleGlass.exr M +57 -1 krita/plugins/formats/exr/tests/kis_exr_test.cpp M +1 -0 krita/plugins/formats/exr/tests/kis_exr_test.h M +39 -0 krita/sdk/tests/testutil.h http://commits.kde.org/calligra/6f54affba1f5b4005d451e1e46f2c7eb10e743f4