{
  "id": 249634,
  "title": "What does OB and OW mean for (7fe0, 0010) key in Dicom Images.",
  "url": "/competitions/siim-covid19-detection/discussion/249634",
  "author_name": "",
  "post_date": "2021-06-29T08:16:25.245832600Z",
  "votes": null,
  "comment_count": 3,
  "views": 0,
  "content": "<p>Hi ,<br>\nI have been trying to convert Dicom images to grayscale and do some analysis on these images.<br>\nI have been using pydicom, I have also already installed GDCM and pylibjpeg . However whenever I am just even trying to read image data in Dicom using:</p>\n<p><code>img = dicom.pixel_array</code></p>\n<p>I am getting error:<br>\n<code>RuntimeError: The following handlers are available to decode the pixel data however they are missing required dependencies: GDCM (req. ), pylibjpeg (req. )\n</code><br>\nI have both the dependency resolved but still same error.</p>\n<p>My code basically working fine for most of the  dcm files but I found out that the file containing <strong>OB</strong> in the (7fe0, 0010) key in Dicom Images create problems whereas <strong>OW</strong> ones run fine. </p>\n<p>I am new to using medical images could someone give me some suggestion regarding this?</p>",
  "messages": [
    {
      "id": "1369224",
      "postDate": "06/29/2021 08:16:25",
      "content": "<p>Hi ,<br>\nI have been trying to convert Dicom images to grayscale and do some analysis on these images.<br>\nI have been using pydicom, I have also already installed GDCM and pylibjpeg . However whenever I am just even trying to read image data in Dicom using:</p>\n<p><code>img = dicom.pixel_array</code></p>\n<p>I am getting error:<br>\n<code>RuntimeError: The following handlers are available to decode the pixel data however they are missing required dependencies: GDCM (req. ), pylibjpeg (req. )\n</code><br>\nI have both the dependency resolved but still same error.</p>\n<p>My code basically working fine for most of the  dcm files but I found out that the file containing <strong>OB</strong> in the (7fe0, 0010) key in Dicom Images create problems whereas <strong>OW</strong> ones run fine. </p>\n<p>I am new to using medical images could someone give me some suggestion regarding this?</p>",
      "rawMarkdown": "Hi ,\nI have been trying to convert Dicom images to grayscale and do some analysis on these images.\nI have been using pydicom, I have also already installed GDCM and pylibjpeg . However whenever I am just even trying to read image data in Dicom using:\n \n`img = dicom.pixel_array`\n\nI am getting error:\n`RuntimeError: The following handlers are available to decode the pixel data however they are missing required dependencies: GDCM (req. ), pylibjpeg (req. )\n`\nI have both the dependency resolved but still same error.\n\nMy code basically working fine for most of the  dcm files but I found out that the file containing **OB** in the (7fe0, 0010) key in Dicom Images create problems whereas **OW** ones run fine. \n\nI am new to using medical images could someone give me some suggestion regarding this?",
      "votes": null
    },
    {
      "id": "1369802",
      "postDate": "06/29/2021 15:37:47",
      "content": "<p>You need to install GDCM. Run this command, and then restart your notebook.</p>\n<p><code>!conda install gdcm -c conda-forge -y</code></p>\n<p>The 'OB' you're seeing is a DICOM VR (Value Representation) which stands for Other Byte. It means the encoding of the byte is defined by the Transfer Syntax.</p>\n<p>'OW' is Other Word .. which is just a string of OB's.</p>\n<p>You're having problems decoding those images because you lack the libraries that understand the encoding of the pixels.</p>",
      "rawMarkdown": "You need to install GDCM. Run this command, and then restart your notebook.\n\n`!conda install gdcm -c conda-forge -y`\n\nThe 'OB' you're seeing is a DICOM VR (Value Representation) which stands for Other Byte. It means the encoding of the byte is defined by the Transfer Syntax.\n\n'OW' is Other Word .. which is just a string of OB's.\n\nYou're having problems decoding those images because you lack the libraries that understand the encoding of the pixels.",
      "votes": null
    },
    {
      "id": "1372208",
      "postDate": "07/01/2021 14:01:10",
      "content": "<p>Thank you so much David for your reply , I am new to medical dicom data so don't know much. Thank you again.</p>",
      "rawMarkdown": "Thank you so much David for your reply , I am new to medical dicom data so don't know much. Thank you again.",
      "votes": null
    },
    {
      "id": "1372407",
      "postDate": "07/01/2021 17:01:51",
      "content": "<p>You're welcome. I've been working in medical imaging for over 25 years, so I'm pretty familiar with the DICOM standard.</p>",
      "rawMarkdown": "You're welcome. I've been working in medical imaging for over 25 years, so I'm pretty familiar with the DICOM standard.",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 1369802,
      "author_name": "davidbroberts",
      "author_url": "",
      "post_date": "06/29/2021 15:37:47",
      "content": "<p>You need to install GDCM. Run this command, and then restart your notebook.</p>\n<p><code>!conda install gdcm -c conda-forge -y</code></p>\n<p>The 'OB' you're seeing is a DICOM VR (Value Representation) which stands for Other Byte. It means the encoding of the byte is defined by the Transfer Syntax.</p>\n<p>'OW' is Other Word .. which is just a string of OB's.</p>\n<p>You're having problems decoding those images because you lack the libraries that understand the encoding of the pixels.</p>",
      "votes": null,
      "replies": [
        {
          "id": 1372208,
          "author_name": "justforgags",
          "author_url": "",
          "post_date": "07/01/2021 14:01:10",
          "content": "<p>Thank you so much David for your reply , I am new to medical dicom data so don't know much. Thank you again.</p>",
          "votes": null,
          "replies": []
        },
        {
          "id": 1372407,
          "author_name": "davidbroberts",
          "author_url": "",
          "post_date": "07/01/2021 17:01:51",
          "content": "<p>You're welcome. I've been working in medical imaging for over 25 years, so I'm pretty familiar with the DICOM standard.</p>",
          "votes": null,
          "replies": []
        }
      ]
    }
  ],
  "raw_markdown_by_id": {
    "1369224": "Hi ,\nI have been trying to convert Dicom images to grayscale and do some analysis on these images.\nI have been using pydicom, I have also already installed GDCM and pylibjpeg . However whenever I am just even trying to read image data in Dicom using:\n \n`img = dicom.pixel_array`\n\nI am getting error:\n`RuntimeError: The following handlers are available to decode the pixel data however they are missing required dependencies: GDCM (req. ), pylibjpeg (req. )\n`\nI have both the dependency resolved but still same error.\n\nMy code basically working fine for most of the  dcm files but I found out that the file containing **OB** in the (7fe0, 0010) key in Dicom Images create problems whereas **OW** ones run fine. \n\nI am new to using medical images could someone give me some suggestion regarding this?",
    "1369802": "You need to install GDCM. Run this command, and then restart your notebook.\n\n`!conda install gdcm -c conda-forge -y`\n\nThe 'OB' you're seeing is a DICOM VR (Value Representation) which stands for Other Byte. It means the encoding of the byte is defined by the Transfer Syntax.\n\n'OW' is Other Word .. which is just a string of OB's.\n\nYou're having problems decoding those images because you lack the libraries that understand the encoding of the pixels.",
    "1372208": "Thank you so much David for your reply , I am new to medical dicom data so don't know much. Thank you again.",
    "1372407": "You're welcome. I've been working in medical imaging for over 25 years, so I'm pretty familiar with the DICOM standard."
  },
  "source": "meta"
}