{
  "id": 1540,
  "title": "Data Discrepancy",
  "url": "/competitions/GestureChallenge/discussion/1540",
  "author_name": "",
  "post_date": "2012-03-15T01:02:07.420Z",
  "votes": null,
  "comment_count": 1,
  "views": 1394,
  "content": "<p>Hi,</p>\r\n<p>I noticed a puzzling discrepancy in the data and I wonder if the administrators can shed any light on it. &nbsp;There are some (maybe many) differences between the movies contained in the devel01-40 download and the devel02 download. &nbsp;To take just one example,\r\n the file K_16.avi (from batch 2) has size 1052554 in the devel01-40 download, while the corresponding file has size 1007874 in the devel02 download.</p>\r\n<p>Is the explanation that one is compressed in the &quot;quasi-lossless&quot; format and one in the lossy format? &nbsp;That could explain this discrepancy, but from reading the download page, it appears both downloads are supposed to be in the quasi-lossless format.</p>\r\n<p>The follow-on question is: how can I ensure that I am getting all the data in one format (devel, validation and final)? &nbsp;I think what I want is the lossless format, but mostly I just want consistency. &nbsp;I definitely don't want to tune my system on one format\r\n and then have the final evaluation be performed on a different format. &nbsp;Thanks.</p>",
  "messages": [
    {
      "id": "9323",
      "postDate": "03/15/2012 01:02:07",
      "content": "<p>Hi,</p>\r\n<p>I noticed a puzzling discrepancy in the data and I wonder if the administrators can shed any light on it. &nbsp;There are some (maybe many) differences between the movies contained in the devel01-40 download and the devel02 download. &nbsp;To take just one example,\r\n the file K_16.avi (from batch 2) has size 1052554 in the devel01-40 download, while the corresponding file has size 1007874 in the devel02 download.</p>\r\n<p>Is the explanation that one is compressed in the &quot;quasi-lossless&quot; format and one in the lossy format? &nbsp;That could explain this discrepancy, but from reading the download page, it appears both downloads are supposed to be in the quasi-lossless format.</p>\r\n<p>The follow-on question is: how can I ensure that I am getting all the data in one format (devel, validation and final)? &nbsp;I think what I want is the lossless format, but mostly I just want consistency. &nbsp;I definitely don't want to tune my system on one format\r\n and then have the final evaluation be performed on a different format. &nbsp;Thanks.</p>",
      "rawMarkdown": "",
      "votes": null
    },
    {
      "id": "9415",
      "postDate": "03/16/2012 15:24:45",
      "content": "<p>[quote=Eric Jackson;9323]</p>\r\n<p>Hi,</p>\r\n<p>I noticed a puzzling discrepancy in the data and I wonder if the administrators can shed any light on it. &nbsp;There are some (maybe many) differences between the movies contained in the devel01-40 download and the devel02 download. &nbsp;To take just one example,\r\n the file K_16.avi (from batch 2) has size 1052554 in the devel01-40 download, while the corresponding file has size 1007874 in the devel02 download.</p>\r\n<p>Is the explanation that one is compressed in the &quot;quasi-lossless&quot; format and one in the lossy format? &nbsp;That could explain this discrepancy, but from reading the download page, it appears both downloads are supposed to be in the quasi-lossless format.</p>\r\n<p>The follow-on question is: how can I ensure that I am getting all the data in one format (devel, validation and final)? &nbsp;I think what I want is the lossless format, but mostly I just want consistency. &nbsp;I definitely don't want to tune my system on one format\r\n and then have the final evaluation be performed on a different format. &nbsp;Thanks.</p>\r\n<p>[/quote]</p>\r\n<p>There are some small differences for a few batches between the release of dec 7 devel0-20 in the sample data and the release of jan 7 because of some improvement I made to correct artifacts introduced by earlier versions of the data collection software affecting\r\n some of the devel files. But the differences are minor and the valid0-20 files are not affected.&nbsp;</p>",
      "rawMarkdown": "",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 9415,
      "author_name": "iguyon",
      "author_url": "",
      "post_date": "03/16/2012 15:24:45",
      "content": "<p>[quote=Eric Jackson;9323]</p>\r\n<p>Hi,</p>\r\n<p>I noticed a puzzling discrepancy in the data and I wonder if the administrators can shed any light on it. &nbsp;There are some (maybe many) differences between the movies contained in the devel01-40 download and the devel02 download. &nbsp;To take just one example,\r\n the file K_16.avi (from batch 2) has size 1052554 in the devel01-40 download, while the corresponding file has size 1007874 in the devel02 download.</p>\r\n<p>Is the explanation that one is compressed in the &quot;quasi-lossless&quot; format and one in the lossy format? &nbsp;That could explain this discrepancy, but from reading the download page, it appears both downloads are supposed to be in the quasi-lossless format.</p>\r\n<p>The follow-on question is: how can I ensure that I am getting all the data in one format (devel, validation and final)? &nbsp;I think what I want is the lossless format, but mostly I just want consistency. &nbsp;I definitely don't want to tune my system on one format\r\n and then have the final evaluation be performed on a different format. &nbsp;Thanks.</p>\r\n<p>[/quote]</p>\r\n<p>There are some small differences for a few batches between the release of dec 7 devel0-20 in the sample data and the release of jan 7 because of some improvement I made to correct artifacts introduced by earlier versions of the data collection software affecting\r\n some of the devel files. But the differences are minor and the valid0-20 files are not affected.&nbsp;</p>",
      "votes": null,
      "replies": []
    }
  ],
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    "9323": "",
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}