title: ImageMagick only capturing first frame of mp4 video
body: <p>All of a sudden, ImageMagick has started only grabbing the first frame of a video file, no matter what slide number I pass into the array. If I select a range, it does output all screenshots as jpgs in that range. Normally this wouldn't be an issue but our company's videos always have a one-two second delay so all I'm getting is a white or black background in my output.</p>
  <p>I am using ImageMagick-7.1.0-Q16-HDRI on Windows 10, running from a command prompt. Here is my command:</p>
  <pre><code>magick.exe &quot;\localfolder\somevideo.mp4[30] -resize 128x128&gt; -border 1 \localfolder\outputfolder\outputimage.jpg&quot;, 0, True
  </code></pre>
  <p>Anyone else ever see this issue?</p>