Why is My Recording Corrupted?

Q: Why is my recording corrupted?

A: You may have modified the source encoder while the live stream was running.

There are times when you may need to change your encoder settings. Typically, it is either related to network issues or quality tuning.  We often see the following types of changes that can cause the recording to become corrupted: 

  • Changing the frame size. Example: Changing from 1080p to 720p.
  • Changing the frame rate. Example: 60fps to 30fps.
  • Changing the profile. Example: High to Baseline.
  • Changing the level. Example: 5.0 to 4.0.

When you utilize the Wowza Video recording feature, it will begin recording when the source is initially received.  That sets the information needed to create the recording. So, if you are sending in a 1080p at 30fps with a High profile and level of 4.0, then the file we output will be published with those details.  If you change any of those variables after we have already begun recording, that is the point at which you will begin to see the corruption in the video.  Likely it will look like a frozen screen and some portion of the playback will show green macroblocking.  Typically, the audio is fine because it has not been affected by the video properties. 

If you make ANY CHANGES to your encoder after you have started the Wowza Video live stream (transcoder), the best action you can take is to stop the live stream (transcoder) and then start it up again. 

This will stop the recording process for the old settings and will pick up the new encoder settings to create the recording with your new desired settings. 


Resources:

Encoding best practices for Wowza Video