No preview/thumbnail for local png wallpapers

[NBOOK]

Hi everyone. I recently noticed that Wallpaper Engine won't display preview for LOCAL PNG wallpapers and only show the default "white monitor on black background" icon. When I click "Open Wallpaper - Open background image", pngs only show icon instead of thumbnails in the file selector. In the Windows Explorer the thumbnails for png are displayed correctly.

Interestingly, jpg works just fine. I can see thumbnails of jpg files in both Wallpaper Engine and its "Open Wallpaper" file selector. And if I rename .png to .jpg, the thumbnail will appear again.

What I've tried: rebuild Windows thumbnail and icon cache, do a complete fresh install of Wallpaper Engine, install beta/older version of Wallpaper Engine, run Wallpaper Engine as admin. I'm running Windows 11 (22621.160), and my image viewer is Honeyview.

So far batch rename all .png to .jpg could be a workaround, but I would like to solve this problem eventually. Please help me, thanks!

[Biohazard]

Hi, the function generating the thumbnails is indeed (supposedly) the same that Windows Explorer uses. However the UI is a 32-bit application and the Explorer runs in 64-bit.

Since you don't have the issue in Windows Explorer, I'm guessing the problem is specifically with the 32-bit PNG thumbnail provider from Windows. You're using an Insider build, so this is something Microsoft will likely fix again, but please make sure to use to feedback hub to let them know too. You could tell them that the 32-bit implementation of 'IThumbnailCache' is failing to generate PNG previews on your PC, this should be specific enough unless the issue is limited to very specific thumbnail parameters.

There is no differentiation between local file formats in Wallpaper Engine itself, the same code runs for JPEG, PNG, BMP and even MP4 and other video formats, it's all calling into the same thumbnail provider of Windows.

[NBOOK]

Originally posted by Biohazard:

Hi, the function generating the thumbnails is indeed (supposedly) the same that Windows Explorer uses. However the UI is a 32-bit application and the Explorer runs in 64-bit.

Since you don't have the issue in Windows Explorer, I'm guessing the problem is specifically with the 32-bit PNG thumbnail provider from Windows. You're using an Insider build, so this is something Microsoft will likely fix again, but please make sure to use to feedback hub to let them know too. You could tell them that the 32-bit implementation of 'IThumbnailCache' is failing to generate PNG previews on your PC, this should be specific enough unless the issue is limited to very specific thumbnail parameters.

There is no differentiation between local file formats in Wallpaper Engine itself, the same code runs for JPEG, PNG, BMP and even MP4 and other video formats, it's all calling into the same thumbnail provider of Windows.

Thanks for the explanation! I'll let MS teams know.

[InvokeMyName]

I'm also seeing this in June 2024. Imported JPG static wallpapers have thumbanails but not PNG. I'm on Windows 11.

[InvokeMyName]

It looks like this is working now. Not sure if maybe it a Windows update fixed it? I haven't seen any Wallpaper Engine updates recently.