title: How to set gop-size on NVenc(HEVC) with ffmpeg?
body: <p>I want to set gop size on NVenc(HEVC) with ffmpeg, but what I did is all failed:</p>
  
  <pre><code>-keyiny 60 or -gop-len 60 or -gop-length 60
  </code></pre>
  
  <p>The command I set is as follows:</p>
  
  <pre><code>ffmpeg -hwaccel cuvid -r 50 -i BasketballDrive_1920x1080_50.ts -c:v hevc_nvenc -preset medium -rc vbr -b:v 2M test_2M.265
  </code></pre>
  
  <p>The default gop-size seems to be 250.</p>
  
  <p>If anyone have some suggestions? Or it cannot set gop-size by command?</p>