How can I implement double speed or slow video playback on Android?

You cannot change the playback speed using MediaPlayer (or ViewoView).

As you know, some of the many video playback player apps can adjust the playback speed.Once upon a time, I checked the libraries that these software depended on, but most software used ffmpeg in the backend. Similar Stack Overflow questions also introduce non-standard player components, but also rely on ffmpeg.It seems inconvenient to publish it, so if you have a detailed request, you will have to use ffmpeg to create your own video playback display.

reference:

• Stack Overflow, Android Video Playback Speed
• Stack Overflow, Using FFmpeg with Android-NDK
• ffmpeg, wiki:CompilationGuide/Android
• Player parts: Vitamio/Presto

MediaPlayer Google provides ExoPlayer that implements considerable functionality as a user application.Based on this implementation, you can also play with the playback time management part.

https://github.com/google/ExoPlayer