Thumbnails not working. about iina HOT 5 OPEN

The Enable thumbnail preview setting found on the UI tab of IINA's settings controls the thumbnails displayed by IINA in the on screen controller when you hover over the slider. This setting and feature is completely unrelated to the thumbnails displayed by the macOS Finder.

The thumbnails displayed by Finder are provided by one part of the macOS Quicklook framework. This Apple framework provides an API that applications can use to provide thumbnails for custom application file types. This is discussed in QuickLook Thumbnailing. The Quick Look Programming Guide indicates the framework searches for plugins in the following directories:

• ~/Library/QuickLook—third party generators, accessible only to logged-in user
• /Library/QuickLook—third party generators, accessible to all users of the system
• /System/Library/QuickLook—Apple-provided generators, accessible to all users of the system

If you check those directories you will not find a generator from IINA. IINA does not generate thumbnails for Finder.

The Apple supplied thumbnail provider has the same limitations as the QuickTime Player. If you try and play a video with QuickTime and it puts up an alert saying "This file contains some media which isn't compatible with QuickTime Player" then that explains why Finder is unable to display a thumbnail. That is what QuickTime does for me when I try and open webm/mkv files.

To obtain thumbnails for more types of video files I use the excellent open source package: QuickLook Video

So what is going wrong in your case? I'm not sure. People have reported problems with Finder thumbnails after macOS upgrades in the past. Comments from users indicated refreshing the macOS QuickLook cache by running the following command in Terminal resolved the problem:

qlmanage -r cache && qlmanage -r && killall Finder

If you search the net for qlmanage -r cache you will find articles discussing this.

from iina.

So if I understand correctly IINA will not generate thumbnails by itself and QuickLook Video is needed? If so, my bad then. It works after installing it and it is my bad.

from iina.

Never worry about submitting an issue that turns out not to be an IINA problem. Fine to inquire about behavior if it seems to involve IINA, which is certainly the case here.

To be clear, yes IINA does not generate the thumbnails seen in Finder. The thumbnails IINA generates are only for its own use with the on screen controller.

There have been requests for IINA to add a Quick Look capability. See issue #3816.

I am still a bit troubled that the issue of Finder thumbnails keeps coming up. Makes me worried there might be something I'm overlooking.

from iina.

Thank you for help. But I have one more question, just not sure if it's okay to ask here, but I will try anyway.
Since you mentioned that QLVideo extension... Does it work at all for you? I am on latest Sonoma and can't make it work, I opened issue about that on QLVideo page, but it seems to not be supported anymore.

from iina.

I just now went to my MacBook Pro running macOS 14.4 that did not have QuickLook Video installed and was missing thumbnails in Finder. After installing I still did not see thumbnails until I clicked on the Refresh button in the QuickLook Video app. That caused Finder to restart. After that the thumbnails started to appear as they were generated. Seems to be working for me.

In the issue you entered in that repository you did not mention clicking the app's Refresh button. Have you tried that? If that does not work then we should continue discussing this in that issue. Next step would be to check the type of encoding of the videos for which thumbnails are not appearing.

from iina.