title: ffmpeg - how to set histogram size?
body: <p>I'm trying to add a histogram to a video using ffmpeg, I'm following <a href="https://trac.ffmpeg.org/wiki/FancyFilteringExamples#waveform" rel="nofollow noreferrer">this example</a>, but I'm having trouble setting the size of the histogram, this is the code I'm using:</p>
  <pre><code>ffmpeg -y -report -i input.mp4 -vf &quot;split[a][b];[a]format=gray,histogram=mode=waveform:waveform_mode=column,vflip,split[c][d];[b]pad=iw:ih+256[padded];[c]geq=g=1:b=1[red];[d]geq=r=1:b=1,crop=in_w:220:0:16[mid];[red][mid]overlay=0:16[wave];[padded][wave]overlay=0:H-h&quot;  output.mp4
  </code></pre>
  <p>I've tried to play around with the <code>pad</code> and <code>crop</code> values without luck.
  How can I set the size of histogram to 100 pixels only?</p>