{
  "id": 118861,
  "title": "First time with 3D data. Some basic doubts.",
  "url": "/competitions/pku-autonomous-driving/discussion/118861",
  "author_name": "",
  "post_date": "2019-11-25T02:31:54.434567200Z",
  "votes": 1,
  "comment_count": 1,
  "views": 0,
  "content": "<ol>\n<li>What to do with the camera calibration? I have read in many discussions that we have to use with the camera calibration matrix. But what it is? And why we have to use it?</li>\n<li>6D pose coordinates. I understand that (pitch, yaw, roll) and relative to (x, y, z). Now what is (x, y, z). Are these values relative to the car camera or we have a reference point (say top left of image). Also, what does z mean in case of 2D image.</li>\n</ol>",
  "messages": [
    {
      "id": "680642",
      "postDate": "11/25/2019 02:31:54",
      "content": "<ol>\n<li>What to do with the camera calibration? I have read in many discussions that we have to use with the camera calibration matrix. But what it is? And why we have to use it?</li>\n<li>6D pose coordinates. I understand that (pitch, yaw, roll) and relative to (x, y, z). Now what is (x, y, z). Are these values relative to the car camera or we have a reference point (say top left of image). Also, what does z mean in case of 2D image.</li>\n</ol>",
      "rawMarkdown": "1. What to do with the camera calibration? I have read in many discussions that we have to use with the camera calibration matrix. But what it is? And why we have to use it?\n2. 6D pose coordinates. I understand that (pitch, yaw, roll) and relative to (x, y, z). Now what is (x, y, z). Are these values relative to the car camera or we have a reference point (say top left of image). Also, what does z mean in case of 2D image.",
      "votes": null
    },
    {
      "id": "680671",
      "postDate": "11/25/2019 03:39:14",
      "content": "<ol>\n<li>For me I've used the camera matrix in order to convert 3d coordinates to 2d image coordinates which is helpful in many ways but especially for visualization.</li>\n<li>x,y,z is based on the camera and z is the distance from the camera in real life.</li>\n</ol>",
      "rawMarkdown": "1. For me I've used the camera matrix in order to convert 3d coordinates to 2d image coordinates which is helpful in many ways but especially for visualization.\n2. x,y,z is based on the camera and z is the distance from the camera in real life.",
      "votes": null
    }
  ],
  "comments": [
    {
      "id": 680671,
      "author_name": "greatgamedota",
      "author_url": "",
      "post_date": "11/25/2019 03:39:14",
      "content": "<ol>\n<li>For me I've used the camera matrix in order to convert 3d coordinates to 2d image coordinates which is helpful in many ways but especially for visualization.</li>\n<li>x,y,z is based on the camera and z is the distance from the camera in real life.</li>\n</ol>",
      "votes": null,
      "replies": []
    }
  ],
  "raw_markdown_by_id": {
    "680642": "1. What to do with the camera calibration? I have read in many discussions that we have to use with the camera calibration matrix. But what it is? And why we have to use it?\n2. 6D pose coordinates. I understand that (pitch, yaw, roll) and relative to (x, y, z). Now what is (x, y, z). Are these values relative to the car camera or we have a reference point (say top left of image). Also, what does z mean in case of 2D image.",
    "680671": "1. For me I've used the camera matrix in order to convert 3d coordinates to 2d image coordinates which is helpful in many ways but especially for visualization.\n2. x,y,z is based on the camera and z is the distance from the camera in real life."
  },
  "source": "meta"
}