Jdiesel 1114 Posted February 10, 2017 Share Posted February 10, 2017 I've been doing some testing with ffmpeg 3.2.2 and noticed that 2-channel aac is being transcoded to mp3 when playing a live tv stream. It occurs on both the release and preview Roku apps. Playing the same stream in the web client the aac audio is copied. If playing a recorded copy of the show, local copy, the aac audio track is direct played. Link to comment Share on other sites More sharing options...
ebr 14947 Posted February 10, 2017 Share Posted February 10, 2017 That tells me we must not know what the audio is when it is in the live stream so have to assume it needs converting to something we know we can play. What is the Live TV source? Link to comment Share on other sites More sharing options...
Jdiesel 1114 Posted February 10, 2017 Author Share Posted February 10, 2017 (edited) The source is an IPTV provider. Like the webclient, the Android TV app is also copying the video and audio streams. FFmpeg 3.2.2 has been causing lots of problems for me so I will revert back to 2.8.20 and do some more testing but if I recall correctly the audio was also being transcoded on FFmpeg 2.8.10. @@ebr I won't be able to troubleshoot for a while but if you would like a copy of the m3u for testing let me know. Edited February 10, 2017 by Jdiesel Link to comment Share on other sites More sharing options...
Luke 37165 Posted February 10, 2017 Share Posted February 10, 2017 We probed it for media info but it was not able to determine the audio bitrate. Without having that information that's why we decided to convert it rather than stream copy. Link to comment Share on other sites More sharing options...
Jdiesel 1114 Posted February 10, 2017 Author Share Posted February 10, 2017 Does the Roku have a audio bitrate limitation that requires it to fallback to a conservative method if unknown? The web app and Android TV app seem to be able to handle the same stream without converting from aac to mp3. Link to comment Share on other sites More sharing options...
Luke 37165 Posted February 10, 2017 Share Posted February 10, 2017 We'd have to look at a log but most likely the probe in those cases succeeded in determining an audio bitrate. Link to comment Share on other sites More sharing options...
Jdiesel 1114 Posted February 10, 2017 Author Share Posted February 10, 2017 I will do some more testing tonight now that I am back on FFmpeg 2.8.10 and gather some log files from different clients and scenarios. Link to comment Share on other sites More sharing options...
speechles 1921 Posted February 10, 2017 Share Posted February 10, 2017 In blue neon it would keep the AAC. Both the unknown audio and default audio are set as AAC to start with. You can of course change these to MP3 or AC3. The AAC audio when transcoded makes clicks and pops on some devices. This is why the official and beta are using MP3. The audio info must not be complete. You can tell by play in blue neon, then fast-fwd a tiny bit, wait for video to play and press OK. Do you see "Audio: ?-> aac" shown on the screen? The question mark means the server didnt supply the audio codec and the app used the codec assigned to unknown audio. You can always force directstream too, any issues when forced? Sent from my Nexus 7 using Tapatalk Link to comment Share on other sites More sharing options...
Jdiesel 1114 Posted February 10, 2017 Author Share Posted February 10, 2017 I will try testing with Blue Neon as well Link to comment Share on other sites More sharing options...
Jdiesel 1114 Posted February 11, 2017 Author Share Posted February 11, 2017 I've reverted back to FFmpeg 2.8.10 and have been successfully been playing streams with copied audio and video on all three Roku apps tonight. I have had a few streams stop playing after about a minute of playback, restarting the stream resulted in it playing properly. Link to comment Share on other sites More sharing options...
Luke 37165 Posted February 11, 2017 Share Posted February 11, 2017 There is a regression in ffmpeg 3.2 that was affecting us. We submitted a patch to ffmpeg, it was approved and merged in but I don't know if it's been packaged into an ffmpeg release or not yet. Link to comment Share on other sites More sharing options...
Jdiesel 1114 Posted February 11, 2017 Author Share Posted February 11, 2017 I recall having issues with ffmpeg 3.2 back in December but thought I'd try again to see if anything had changed. Not that I feel I need 3.2, just curious to test it. Any thoughts on forking ffmpeg and including a customized build as part Emby server for consistency? Link to comment Share on other sites More sharing options...
Luke 37165 Posted February 11, 2017 Share Posted February 11, 2017 I suppose if there is ever a need for customization but we don't have that need right now. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now