Answers.Body: <p>Remove the pipe character.</p>
  <p><code>ffmpeg -f v4l2 -standard PAL -i /dev/video0 -f alsa -thread_queue_size 512 -i hw:0,0 -preset superfast -crf 25 -r 25 -aspect 4:3 -acodec libmp3lame -b:v 6M -b:a 128k -ac 2 -ar 48000 /vids/vid1.avi -b:v 500k -b:a 128k -ac 2 -ar 48000 -y /opt/lampp/htdocs/preview.mp4</code></p>
  <p>(mp3 is not standard in MP4 so let ffmpeg pick the default audio codec)</p>
  
Answers.ContentLicense: CC BY-SA 4.0
Answers.CreationDate: 2021-02-09T17:28:38.123Z
Answers.LastActivityDate: 2021-02-09T17:28:38.123Z
Answers.UserDisplayName: Gyan
Body: <p>I've been struggling with a ffmpeg-related issue for a few days now.
  What I am trying to accomplish is to grab AV signal from a single input (/dev/video0), then save it into two files simultaneously.</p>
  <ul>
  <li>Output no. 1: raw AVI file, for further editing</li>
  <li>Output no. 2: preview mp4 file, to work as a preview within an embedded VideoJS player on an webapp.</li>
  </ul>
  <p>Here's my command:</p>
  <pre><code>ffmpeg -f v4l2 -standard PAL -i /dev/video0 -f alsa -thread_queue_size 512 -i hw:0,0 -preset superfast -crf 25 -r 25 -aspect 4:3 -acodec libmp3lame -b:v 6M -b:a 128k -channels 2 -ar 48000 /vids/vid1.avi | -acodec libmp3lame  -b:v 500k -b:a 128k -channels 2 -ar 48000 -y /opt/lampp/htdocs/preview.mp4
  </code></pre>
  <p>The command above doesn't seem to work for me. Where have I gone wrong?</p>
  
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2021-02-09T15:20:22.677Z
Comments.Text: *doesn't seem to work * --> what's wrong?
Comments.UserDisplayName: Gyan
Comments.ContentLicense: CC BY-SA 4.0
Comments.CreationDate: 2021-02-09T15:34:54.070Z
Comments.Text: Using this command makes output 1 generate nice and smooth, while output 2 doesn't generate at all.
Comments.UserDisplayName: Radek
Tags: <ffmpeg>
Title: ffmpeg - one input, two outputs - separate instances
UserDisplayName: Radek
ThreadText: # ffmpeg - one input, two outputs - separate instances
  
  (Asked by: username_0 on 2021-02-09)
  
  I've been struggling with a ffmpeg-related issue for a few days now.
  What I am trying to accomplish is to grab AV signal from a single input (/dev/video0), then save it into two files simultaneously.
  
  * Output no. 1: raw AVI file, for further editing
  * Output no. 2: preview mp4 file, to work as a preview within an embedded VideoJS player on an webapp.
  
  Here's my command:
  
  ```
  ffmpeg -f v4l2 -standard PAL -i /dev/video0 -f alsa -thread_queue_size 512 -i hw:0,0 -preset superfast -crf 25 -r 25 -aspect 4:3 -acodec libmp3lame -b:v 6M -b:a 128k -channels 2 -ar 48000 /vids/vid1.avi | -acodec libmp3lame  -b:v 500k -b:a 128k -channels 2 -ar 48000 -y /opt/lampp/htdocs/preview.mp4
  
  ```
  
  The command above doesn't seem to work for me. Where have I gone wrong?
  
  **Tags:** ffmpeg
  
  > **Comments:**
  > **username_1**: *doesn't seem to work * --> what's wrong?  
  > **username_0**: Using this command makes output 1 generate nice and smooth, while output 2 doesn't generate at all.  
  
  ---
  
  ## 1 answers
  
  ### Answer by username_1 on 2021-02-09. Score: 1
  
  Remove the pipe character.
  
  `ffmpeg -f v4l2 -standard PAL -i /dev/video0 -f alsa -thread_queue_size 512 -i hw:0,0 -preset superfast -crf 25 -r 25 -aspect 4:3 -acodec libmp3lame -b:v 6M -b:a 128k -ac 2 -ar 48000 /vids/vid1.avi -b:v 500k -b:a 128k -ac 2 -ar 48000 -y /opt/lampp/htdocs/preview.mp4`
  
  (mp3 is not standard in MP4 so let ffmpeg pick the default audio codec)
  
  
  ---
  
  