title: How Kitti calibration matrix was calculated?
body: <p>I working with other dataset (no kitti), but I need to convert it in kitti dataset format. I can't understand how calibration matrices were calculated in kitti. Example:</p>
  
  <p>camera 2 (P2) calibration matrix from calib.txt:</p>
  
  <pre><code>[718.856     0     607.1928  -386.1448]
  [   0     718.856  185.2157      0    ]
  [   0        0        1          0    ]
  </code></pre>
  
  <p>I know, that</p>
  
  <pre><code>[718.856     0     607.1928]
  [   0     718.856  185.2157]
  [   0        0        1    ]
  </code></pre>
  
  <p>-- are K - camera intrinsic. But what the last column mean?</p>
  
  <p>I suggested, that it's an offset from 0-th camera, measured in pixels.
  From <a href="http://www.cvlibs.net/datasets/kitti/setup.php" rel="nofollow noreferrer">kitti sensor setup</a>, I know that Cam 2 offsets from Cam 0 for 0.06m negatively by axis X. 
  <a href="https://www.avsupply.com/ITM/29755/FL2-14S3C-C.html" rel="nofollow noreferrer">Camera</a> pixel size is 4.65um. But</p>
  
  <pre><code>0.06[m] / (4.65 * 10^(-6)[m]) != 386.1448 [pixels]
  </code></pre>
  
  <p>So what does the last column mean? And how to calculate calibration matrix just like in kitti.</p>