No thumbnails on 3.04

[AuroraWright]

Your description of the problem here!
Same as #169 (comment)

---

QuickLook Video 3.04
macOS: バージョン15.7.4（ビルド24G517）
Hardware: MacBookPro18,2, Apple M1 Max, neon=yes
Previewer: Not found
Thumbnailer: Not found
Media Formats: 3.04
Media Codecs: 3.04

file.mkv:
ContentType: 'org.matroska.mkv', subtype of 'public.audio'=no, subtype of 'public.movie'=yes
Playable: No
Thumbnail: Error Domain=QLThumbnailErrorDomain Code=0 "Could not generate a thumbnail" UserInfo={NSUnderlyingError=0x6000031853e0 {Error Domain=QLThumbnailErrorDomain Code=102 "(null)"}}
Spotlight: Imported 'file.mkv' of type 'org.matroska.mkv' with plugIn /Applications/QuickLook Video.app/Contents/Library/Spotlight/QLVideo Metadata.mdimporter. 40 attributes returned

{
  "programs": [
  ],
  "stream_groups": [
  ],
  "streams": [
    {
      "codec_name": "h264",
      "profile": "High 10",
      "codec_type": "video",
      "codec_tag_string": "[0][0][0][0]",
      "width": 1440,
      "height": 1080,
      "display_aspect_ratio": "4:3",
      "pix_fmt": "yuv420p10le",
      "color_range": "tv",
      "color_space": "bt709",
      "extradata_size": 50,
      "disposition": {
        "default": 1,
        "attached_pic": 0,
        "timed_thumbnails": 0
      }
    },
    {
      "codec_name": "flac",
      "codec_type": "audio",
      "codec_tag_string": "[0][0][0][0]",
      "sample_fmt": "s32",
      "channel_layout": "stereo",
      "extradata_size": 34,
      "disposition": {
        "default": 1,
        "attached_pic": 0,
        "timed_thumbnails": 0
      }
    },
    {
      "codec_name": "ass",
      "codec_type": "subtitle",
      "codec_tag_string": "[0][0][0][0]",
      "extradata_size": 1147,
      "disposition": {
        "default": 0,
        "attached_pic": 0,
        "timed_thumbnails": 0
      }
    }
  ],
  "chapters": [
    {
      "start_time": "0.000000",
      "end_time": "682.300000"
    },
    {
      "start_time": "682.300000",
      "end_time": "757.375000"
    },
    {
      "start_time": "757.375000",
      "end_time": "788.410000"
    }
  ],
  "format": {
    "format_name": "matroska,webm",
    "duration": "231.564000",
    "size": "145152428",
    "bit_rate": "5014680",
    "probe_score": 100
  }
}

[benjaminhoong]

I'm having the same issue too, majority of the thumbnails are black. Out of 120 videos in a folder, only 32 have thumbnails working.

This is what I copied from the app using "Report an Issue":

---

QuickLook Video 3.04
macOS: Version 26.3 (Build 25D125)
Hardware: Macmini9,1, Apple M1, neon=yes
Previewer: Not found
Thumbnailer: Not found
Media Formats: 3.04
Media Codecs: 3.04

file.mkv:
ContentType: 'org.matroska.mkv', subtype of 'public.audio'=no, subtype of 'public.movie'=yes
Playable: No
Thumbnail: Error Domain=QLThumbnailErrorDomain Code=0 "Could not generate a thumbnail" UserInfo={NSUnderlyingError=0xc58029f80 {Error Domain=QLThumbnailErrorDomain Code=102 "(null)"}}
Spotlight: Imported 'file.mkv' of type 'com.firecore.fileformat.mkv' with plugIn /Applications/QuickLook Video.app/Contents/Library/Spotlight/QLVideo Metadata.mdimporter. 41 attributes returned

{
  "programs": [
  ],
  "stream_groups": [
  ],
  "streams": [
    {
      "codec_name": "hevc",
      "profile": "Main 10",
      "codec_type": "video",
      "codec_tag_string": "[0][0][0][0]",
      "width": 1920,
      "height": 1080,
      "display_aspect_ratio": "16:9",
      "pix_fmt": "yuv420p10le",
      "color_range": "tv",
      "color_space": "bt709",
      "color_primaries": "bt709",
      "extradata_size": 2483,
      "disposition": {
        "default": 1,
        "attached_pic": 0,
        "timed_thumbnails": 0
      }
    },
    {
      "codec_name": "eac3",
      "codec_type": "audio",
      "codec_tag_string": "[0][0][0][0]",
      "sample_fmt": "fltp",
      "channel_layout": "5.1(side)",
      "disposition": {
        "default": 1,
        "attached_pic": 0,
        "timed_thumbnails": 0
      }
    },
    {
      "codec_name": "ass",
      "codec_type": "subtitle",
      "codec_tag_string": "[0][0][0][0]",
      "extradata_size": 581,
      "disposition": {
        "default": 0,
        "attached_pic": 0,
        "timed_thumbnails": 0
      }
    }
  ],
  "chapters": [
  ],
  "format": {
    "format_name": "matroska,webm",
    "duration": "1291.872000",
    "size": "315201177",
    "bit_rate": "1951903",
    "probe_score": 100
  }
}

[chrisgrieser]

same here. Reported the issue in #165 and #171, but the issue still is not fixed with 3.04.

System Settings still only report spotlight as extension, but no media extensions, even after login/logout.

Last working version was 2.23

---

Here my "Report issue" output:
QuickLook Video 3.04
macOS: Version 26.3 (Build 25D125)
Hardware: iMac21,1, Apple M1, neon=yes
Previewer: Not found
Thumbnailer: Not found
Media Formats: Not found
Media Codecs: Not found

file.mp4:
ContentType: 'public.mpeg-4', subtype of 'public.audio'=no, subtype of 'public.movie'=yes
Playable: No
Thumbnail: Error Domain=QLThumbnailErrorDomain Code=0 "Could not generate a thumbnail" UserInfo={NSUnderlyingError=0x7d1474c90 {Error Domain=QLThumbnailErrorDomain Code=102 "(null)"}}
Spotlight: Imported 'file.mp4' of type 'public.mpeg-4' with plugIn /System/Library/Spotlight/CoreMedia.mdimporter. 28 attributes returned

{
  "programs": [
    {
      "streams": [
        {
          "codec_name": "h264",
          "profile": "High",
          "codec_type": "video",
          "codec_tag_string": "[27][0][0][0]",
          "width": 1920,
          "height": 1080,
          "display_aspect_ratio": "16:9",
          "pix_fmt": "yuv420p",
          "extradata_size": 80,
          "disposition": {
          }
        },
        {
          "codec_name": "aac",
          "profile": "LC",
          "codec_type": "audio",
          "codec_tag_string": "[15][0][0][0]",
          "sample_fmt": "fltp",
          "channel_layout": "stereo",
          "disposition": {
          }
        },
        {
          "codec_name": "timed_id3",
          "codec_type": "data",
          "codec_tag_string": "ID3 ",
          "disposition": {
          }
        }
      ]
    }
  ],
  "stream_groups": [
  ],
  "streams": [
    {
      "codec_name": "h264",
      "profile": "High",
      "codec_type": "video",
      "codec_tag_string": "[27][0][0][0]",
      "width": 1920,
      "height": 1080,
      "display_aspect_ratio": "16:9",
      "pix_fmt": "yuv420p",
      "extradata_size": 80,
      "disposition": {
        "default": 0,
        "attached_pic": 0,
        "timed_thumbnails": 0
      }
    },
    {
      "codec_name": "aac",
      "profile": "LC",
      "codec_type": "audio",
      "codec_tag_string": "[15][0][0][0]",
      "sample_fmt": "fltp",
      "channel_layout": "stereo",
      "disposition": {
        "default": 0,
        "attached_pic": 0,
        "timed_thumbnails": 0
      }
    },
    {
      "codec_name": "timed_id3",
      "codec_type": "data",
      "codec_tag_string": "ID3 ",
      "disposition": {
        "default": 0,
        "attached_pic": 0,
        "timed_thumbnails": 0
      }
    }
  ],
  "chapters": [
  ],
  "format": {
    "format_name": "mpegts",
    "duration": "1983.960000",
    "size": "1082200192",
    "bit_rate": "4363798",
    "probe_score": 50
  }
}

[benjaminhoong]

Media Extensions showing up for me no problem, but just having the issue with the thumbnails.

[Marginal]

@AuroraWright @benjaminhoong Thanks. I have been able to reproduce a similar issue - some parts of macOS (e.g. Finder) use the media extensions while others (e.g. QuickLook Thumbnailing process) don't. Looking through the logs it appears that the Thumbnailing process sees the media extensions, but doesn't use them to generate the thumbnail. I don't know why, but it looks like a bug in macOS.

In any case the solution appears to be to reboot after installing QuickLook Video and hope for the best.

@chrisgrieser

1. I don't know why the media extensions aren't showing up on your computer. Do you have some third-party antimalware software that is suppressing them? In the absence of the media extensions you aren't going to see any thumbnails or previews for .mkv, .webm, or any other file types supported by this app.
2. This app doesn't generate thumbnails, previews or metadata for .mp4 files https://github.com/Marginal/QLVideo/wiki/Troubleshooting#finder-doesnt-show-thumbnails-or-previews-for-some-native-video-files . Any problems with them are either a problem with the files themselves or with your copy of macOS.

[chrisgrieser]

@Marginal

1. After a restart, the media extensions are now showing up for me, for whatever reason. However, none of the thumbnails are working, thumbnail-wise it's still as if qlvideo was not installed.
2. Not sure what the cause is with the mp4 files, but with 2.23 they definitely did get thumbnails and stopped getting them since 3.x, so I'm not sure whether this really is caused by the files. Only affects ~10% of them though. However, I also do not get any thumbnails for mkv files, like AuroraWright and benjaminhoong.

Nonetheless, it looks like I otherwise at the same place as AuroraWright and benjaminhoong: working media extensions, but no thumbnails for mkv. I did do a restart (which made the media extensions show up), but further restarts do not seem to fix the issue.

Since the thumbnails did work fine in version 2, can the respective change not simply be reverted for now?

[benjaminhoong]

I reverted back to 2.23 in the meantime, seems to work fine on Tahoe. I think Media Extensions in version 3 are just the new way of integrating this plugin into the OS?

[andy0130tw]

I can confirm that downgrading to v2 makes mp4 (those which QuickTime cannot play natively) thumbnails appear again.