title: ffmpeg reduce image quality, NOT size
body: <p>I successfully made a thumbnail from video using FFMPEG.</p>
  
  <pre><code>ffmpeg -i 'video_location' -vf thumbnail,scale=160:120  -frames:v 1 'image_location.jpg'
  </code></pre>
  
  <p>Is there any 'ffmpeg' command to reduce image size without changing image scale?? </p>