user14444: What are the WebM (VP9+opus) encoding settings compatible for YouTube import for a video with a still image ?
I tried PAL and NTSC framerates with 48kHz stereo and and image size of 640x360 and kept every other parameters' defaults :
$ ffmpeg -i myOriginialPureAudioFile-CUT.opus -i myAudioFile.png -ac 2 -s 640x360 -strict strict -r pal myAudioFile.webm

But YouTube says :

The video has failed to process. Please make sure you are uploading a
  supported file type.


user1871: Rather than framerate, the issue is there's only one frame. You'll have to loop the image.
ffmpeg -i Audio.opus -loop 1 -i image.png -pix_fmt yuv420p -ac 2 -s 640x360 -strict strict -r pal -shortest myAudioFile.webm


-loop 1 : infinitely loops over the same image
-shortest : stops encoding when the shortest input stream has entirely been encoded


14444: <p>What are the WebM (VP9+opus) encoding settings compatible for YouTube import for a video with a still image ?</p>

<p>I tried PAL and NTSC framerates with 48kHz stereo and and image size of 640x360 and kept every other parameters' defaults :</p>

<pre><code>$ ffmpeg -i myOriginialPureAudioFile-CUT.opus -i myAudioFile.png -ac 2 -s 640x360 -strict strict -r pal myAudioFile.webm
</code></pre>

<p>But YouTube says :</p>

<blockquote>
  <p>The video has failed to process. Please make sure you are uploading a
  supported file type.</p>
</blockquote>
 1871: <p>Rather than framerate, the issue is there's only one frame. You'll have to loop the image.</p>

<pre><code>ffmpeg -i Audio.opus -loop 1 -i image.png -pix_fmt yuv420p -ac 2 -s 640x360 -strict strict -r pal -shortest myAudioFile.webm
</code></pre>

<ul>
<li><code>-loop 1</code> : infinitely loops over the same image</li>
<li><code>-shortest</code> : stops encoding when the shortest input stream has entirely been encoded</li>
</ul>
