Created attachment 175444 [details] IMG_20241019_195232.heif This image can be opened/imported inside digiKam, Gimp, Inkscape, Krita, darktable, even Dolphin can preview it as thumbnail. Gwenview can view other heif images but it fails to open this one with the following error: gwenview IMG_20241019_195232.heif kf.i18n.kuit: "Unknown subcue ':whatsthis,' in UI marker in context {@info:whatsthis, %1 the action's text}." org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-aptus-mos" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-arq" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-bay" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-bmq" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-cap" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-cine" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-cs1" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-dc2" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-drf" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-dxo" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-epson-eip" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-epson-erf" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-fff" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-hasselblad-3fr" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-iiq" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-kodak-dcs" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-kodak-kc2" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-mamiya-mef" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-mfw" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-minolta-mdc" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-mng" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-obm" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-ori" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-pfm" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-ptx" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-pxn" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-pxr" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-qtk" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-r3d" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-raw" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-rdc" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-rwl" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-rwz" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-samsung-srw" org.kde.kdegraphics.gwenview.lib: Unresolved mime type "image/x-sti" org.kde.kdegraphics.gwenview.lib: Unresolved raw mime type "image/x-samsung-srw" heif_decode_image error: Invalid input: Unknown NCLX matrix coefficients: Unknown error org.kde.kdegraphics.gwenview.lib: QImageReader::read() using format hint "heic" failed: "Unknown error" org.kde.kdegraphics.gwenview.lib: A bad Qt image decoder moved the buffer to 1083944 in a call to canRead()! Rewinding. org.kde.kdegraphics.gwenview.lib: Image format is actually "heif" not "heic" heif_decode_image error: Invalid input: Unknown NCLX matrix coefficients: Unknown error heif_decode_image error: Invalid input: Unknown NCLX matrix coefficients: Unknown error
The last six lines in the log show that it's an issue with the decoder plugin, possibly triggered by a corrupt image file. I'd recommend reporting it to Qt.
(In reply to Nate Graham from comment #1) > The last six lines in the log show that it's an issue with the decoder > plugin, possibly triggered by a corrupt image file. I'd recommend reporting > it to Qt. But the same version of libheif decoder is used by gwenview, digikam, dolphin, gimp, krita... so why only gwenview fails to view it?
Even the command heif-dec doesn't show those errors, it seems gweenview is not directly using libheif like how other apps do it.
Possibly not. We can look into it.
The problem is that HEIF/HEIC files created by Xiaomi 14 phones are not in full harmony with standards. The files have invalid value in "matrix coefficients" Gwenview decode HEIF files via kimg_heif.so Qt plug-in from kimageformats. The plug-in uses strict decoding for security reasons and invalid files are rejected. If we don't use the strict decoding, the file would be decodable, but potential of security risk would be higher. Ideal solution would be that Xiaomi customers request the Xiaomi company to update their software to generate 100% compatible files. There is no problems with files created by iPhone or Samsung phones.