title: Lossless jpeg batch crop on Linux
body: <p>I need to crop a number of images in <code>jpeg</code> format by 20 pixels on the right side losslessly on Linux.</p>
  <p>I checked <code>jpegtran</code>, but it needs the file size in pixels before cropping, and I don't know how to build a batch file with that.</p>
  <p>How can I losslessly crop 20 pixels from the right side of images programmatically?</p>