{
  "id": 123381,
  "title": "Another data leakage (threads and lookahead_threads)",
  "url": "/competitions/deepfake-detection-challenge/discussion/123381",
  "author_name": "",
  "post_date": "2019-12-27T08:36:51.704795900Z",
  "votes": 6,
  "comment_count": 3,
  "views": 0,
  "content": "<p>Hello,</p>\n\n<p>I think there is another data leakage.\nFor fake videos:\nthreads=60 lookahead_threads=10\nor\nthreads=34 lookahead_threads=5 </p>\n\n<p>For real videos:\nthreads=36 lookahead_threads=6</p>\n\n<p>Ex. for dfdc_train_part_0:</p>\n\n<p>grep -r '/videos/dfdc_train_part_0' -e ' threads=60 lookahead_threads=10'|wc -l\n983\ngrep -r '/videos/dfdc_train_part_0' -e ' threads=34 lookahead_threads=5'|wc -l\n297\ngrep -r '/videos/dfdc_train_part_0' -e ' threads=36 lookahead_threads=6' |wc -l\n54</p>",
  "messages": [
    {
      "id": "704264",
      "postDate": "12/27/2019 08:36:51",
      "content": "<p>Hello,</p>\n\n<p>I think there is another data leakage.\nFor fake videos:\nthreads=60 lookahead_threads=10\nor\nthreads=34 lookahead_threads=5 </p>\n\n<p>For real videos:\nthreads=36 lookahead_threads=6</p>\n\n<p>Ex. for dfdc_train_part_0:</p>\n\n<p>grep -r '/videos/dfdc_train_part_0' -e ' threads=60 lookahead_threads=10'|wc -l\n983\ngrep -r '/videos/dfdc_train_part_0' -e ' threads=34 lookahead_threads=5'|wc -l\n297\ngrep -r '/videos/dfdc_train_part_0' -e ' threads=36 lookahead_threads=6' |wc -l\n54</p>",
      "rawMarkdown": "Hello,\n\nI think there is another data leakage.\nFor fake videos:\nthreads=60 lookahead_threads=10\nor\nthreads=34 lookahead_threads=5 \n\nFor real videos:\nthreads=36 lookahead_threads=6\n\nEx. for dfdc_train_part_0:\n\ngrep -r '/videos/dfdc_train_part_0' -e ' threads=60 lookahead_threads=10'|wc -l\n983\ngrep -r '/videos/dfdc_train_part_0' -e ' threads=34 lookahead_threads=5'|wc -l\n297\ngrep -r '/videos/dfdc_train_part_0' -e ' threads=36 lookahead_threads=6' |wc -l\n54",
      "votes": null
    },
    {
      "id": "704605",
      "postDate": "12/27/2019 17:31:08",
      "content": "<p>Thanks for sharing. We have this on our radar, and hope to have it included in the impending rescore for the public test set. It’s taking a bit longer to resolve the various issues with the host, so we’re aiming for a fix next week.</p>",
      "rawMarkdown": "Thanks for sharing. We have this on our radar, and hope to have it included in the impending rescore for the public test set. It’s taking a bit longer to resolve the various issues with the host, so we’re aiming for a fix next week.",
      "votes": null
    },
    {
      "id": "704791",
      "postDate": "12/28/2019 02:19:51",
      "content": "<p>This is not a leak.\nLooking at all data for <code>threads</code> and <code>lookahead_threads</code> for the full train set shows no correlation to the labels.  Most importantly, for a given scene, all values for threads and lookahead_threads are identical.  This (and other obscure metadata) can be pulled and analyzed using <a href=\"https://mediaarea.net/en/MediaInfo/Download/Ubuntu\">mediainfo</a></p>\n\n<p><code>mediainfo ../input/dfdc_train_all/dfdc_train_part_31/mmqhndqekm.mp4 | grep Encoding | cut -d ':' -f 2- | tr '/' '\\n' | cut -d ' ' -f 2-</code>\n<img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F888191%2Fd6b8d31609a53f4d0022bb4793d185c4%2Fthreads_lookahead.jpg?generation=1577499561813664&amp;alt=media\" alt=\"\"></p>",
      "rawMarkdown": "This is not a leak.\nLooking at all data for `threads` and `lookahead_threads` for the full train set shows no correlation to the labels.  Most importantly, for a given scene, all values for threads and lookahead_threads are identical.  This (and other obscure metadata) can be pulled and analyzed using [mediainfo](https://mediaarea.net/en/MediaInfo/Download/Ubuntu)\n\n`mediainfo ../input/dfdc_train_all/dfdc_train_part_31/mmqhndqekm.mp4 | grep Encoding | cut -d ':' -f 2- | tr '/' '\\n' | cut -d ' ' -f 2-`\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F888191%2Fd6b8d31609a53f4d0022bb4793d185c4%2Fthreads_lookahead.jpg?generation=1577499561813664&amp;alt=media)",
      "votes": null
    },
    {
      "id": "705672",
      "postDate": "12/29/2019 09:20:57",
      "content": "<p>Like <a href=\"/tivfrvqhs5\">@tivfrvqhs5</a> said, the values of <code>threads</code> and <code>lookahead_threads</code> are indeed evenly spread across real and fake videos. It's irrelevant metadata and not a leak.</p>",
      "rawMarkdown": "Like @tivfrvqhs5 said, the values of `threads` and `lookahead_threads` are indeed evenly spread across real and fake videos. It's irrelevant metadata and not a leak.",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 704605,
      "author_name": "juliaelliott",
      "author_url": "",
      "post_date": "12/27/2019 17:31:08",
      "content": "<p>Thanks for sharing. We have this on our radar, and hope to have it included in the impending rescore for the public test set. It’s taking a bit longer to resolve the various issues with the host, so we’re aiming for a fix next week.</p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 704791,
      "author_name": "tivfrvqhs5",
      "author_url": "",
      "post_date": "12/28/2019 02:19:51",
      "content": "<p>This is not a leak.\nLooking at all data for <code>threads</code> and <code>lookahead_threads</code> for the full train set shows no correlation to the labels.  Most importantly, for a given scene, all values for threads and lookahead_threads are identical.  This (and other obscure metadata) can be pulled and analyzed using <a href=\"https://mediaarea.net/en/MediaInfo/Download/Ubuntu\">mediainfo</a></p>\n\n<p><code>mediainfo ../input/dfdc_train_all/dfdc_train_part_31/mmqhndqekm.mp4 | grep Encoding | cut -d ':' -f 2- | tr '/' '\\n' | cut -d ' ' -f 2-</code>\n<img src=\"https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F888191%2Fd6b8d31609a53f4d0022bb4793d185c4%2Fthreads_lookahead.jpg?generation=1577499561813664&amp;alt=media\" alt=\"\"></p>",
      "votes": null,
      "replies": []
    },
    {
      "id": 705672,
      "author_name": "dagnelies",
      "author_url": "",
      "post_date": "12/29/2019 09:20:57",
      "content": "<p>Like <a href=\"/tivfrvqhs5\">@tivfrvqhs5</a> said, the values of <code>threads</code> and <code>lookahead_threads</code> are indeed evenly spread across real and fake videos. It's irrelevant metadata and not a leak.</p>",
      "votes": null,
      "replies": []
    }
  ],
  "raw_markdown_by_id": {
    "704264": "Hello,\n\nI think there is another data leakage.\nFor fake videos:\nthreads=60 lookahead_threads=10\nor\nthreads=34 lookahead_threads=5 \n\nFor real videos:\nthreads=36 lookahead_threads=6\n\nEx. for dfdc_train_part_0:\n\ngrep -r '/videos/dfdc_train_part_0' -e ' threads=60 lookahead_threads=10'|wc -l\n983\ngrep -r '/videos/dfdc_train_part_0' -e ' threads=34 lookahead_threads=5'|wc -l\n297\ngrep -r '/videos/dfdc_train_part_0' -e ' threads=36 lookahead_threads=6' |wc -l\n54",
    "704605": "Thanks for sharing. We have this on our radar, and hope to have it included in the impending rescore for the public test set. It’s taking a bit longer to resolve the various issues with the host, so we’re aiming for a fix next week.",
    "704791": "This is not a leak.\nLooking at all data for `threads` and `lookahead_threads` for the full train set shows no correlation to the labels.  Most importantly, for a given scene, all values for threads and lookahead_threads are identical.  This (and other obscure metadata) can be pulled and analyzed using [mediainfo](https://mediaarea.net/en/MediaInfo/Download/Ubuntu)\n\n`mediainfo ../input/dfdc_train_all/dfdc_train_part_31/mmqhndqekm.mp4 | grep Encoding | cut -d ':' -f 2- | tr '/' '\\n' | cut -d ' ' -f 2-`\n![](https://www.googleapis.com/download/storage/v1/b/kaggle-user-content/o/inbox%2F888191%2Fd6b8d31609a53f4d0022bb4793d185c4%2Fthreads_lookahead.jpg?generation=1577499561813664&amp;alt=media)",
    "705672": "Like @tivfrvqhs5 said, the values of `threads` and `lookahead_threads` are indeed evenly spread across real and fake videos. It's irrelevant metadata and not a leak."
  },
  "source": "meta"
}