When I save some images in HEIC format, the resulting files aquire corruption in the form of several vertical black lines at the bottom of the image and several horizontal black lines at the right of the image.
Steps to reproduce:
Create new canvas, dimensions 3457x2799 pixels, 96 pixels/inch.
Save as using heic format, default options.
Observe corruption at the right and bottom of the image in the save preview window.
Proceed with the save anyway. Close paint.net file and reload file.
The same corruption is shown in the preview is now visible in the canvas in paint.net.
Other observations:
The corruption only seems to occur if the image dimensions are odd numbers, and for larger image sizes.
I have tried on three different machines, all with different graphics hardware, all with the same result.
It seems WIC HEIC codec is rendering the image data in "tiles" of 512x512 pixels. In what would be the last column and row of the image, each "tile" has been offset by one or two pixels leaving a black lines. Repeating the save causes the black lines to become wider (which can be observed in the save preview or when the file is next loaded).
Any ideas as to what's going on here would be appreciated. I hope I'm not missing something obvious.
I am using:
paint.net 4.2.14 (Final 4.214.7601.39231) (default install from the Microsoft Store).
Windows 10 Pro x64 (10.0.19042.0)
Microsoft HEIF Image Extensions (1.0.32532.0)
msheif_store.dll
C:\Program Files\WindowsApps\Microsoft.HEIFImageExtension_1.0.32532.0_x64__8wekyb3d8bbwe\x64\msheif_store.dll, version=10.0.20207.1001 (WinBuild.160101.0800)
msheif.dll
C:\WINDOWS\system32\msheif.dll, version=10.0.19041.1 (WinBuild.160101.0800)
