Hooking up a MediaSource for specific subtitles when a video does not have them causes looping to fail after the 2nd play through

[Ste-RH]

[REQUIRED] Issue description

Defining a subtitle media source of specific type/language (via createTextSampleFormat) causes a video to not loop a second time. If I pass NULL into the 'sampleMimeType and 'language' the video will loop perfectly over and over and over again as it should do.

[REQUIRED] Reproduction steps

I changed the demo code to loop and added the following video to media.exolist.json:
{ "name": "test", "uri": "https://html5demos.com/assets/dizzy.mp4", "subtitle_uri": "https://html5demos.com/assets/dizzy.mp4", "subtitle_mime_type": "text/vtt", "subtitle_language": "en" }

[REQUIRED] Link to test content

Using: https://html5demos.com/assets/dizzy.mp4

[REQUIRED] A full bug report captured from the device

testreport.txt The important part of the log can be seen by searching for 'TextRenderer' I think.

[REQUIRED] Version of ExoPlayer being used

2.11.5

[REQUIRED] Device(s) and version(s) of Android being used

Nexus 7 (2nd gen), Android Version: 6.0.1

[icbaker]

I can't reproduce the problem. I added player.setRepeatMode(Player.REPEAT_MODE_ALL); here:

ExoPlayer/demos/main/src/main/java/com/google/android/exoplayer2/demo/PlayerActivity.java

Line 386 in 6026b91

player.addAnalyticsListener(new EventLogger(trackSelector));

I tried with both REPEAT_MODE_ALL and REPEAT_MODE_ONE.

I see the video play (with no visible subtitles, as expected). When it reaches the end it plays again.

Aside: I'm not sure passing an MP4 file with embedded WebVTT subtitles to subtitle_uri is supported - that option is designed for side-loading of subtitle text files as described here:
https://exoplayer.dev/media-sources.html#side-loading-a-subtitle-file

The error you see in the log seems like ExoPlayer is trying to decode 'random' bytes as a WebVTT file and is upset that it doesn't start with the WEBVTT magic string. That may happen if it tries to decode a full MP4 file as a WebVTT file

Would you be able to clarify your reproduction steps to help me understand the problem?

[Ste-RH]

It is the end of the second play-through that then does not loop.

So let the mp4 play through once, loop, play again...it's at the end of that loop where it fails to loop again.

I originally came across this issue loading an HLS stream that did not include a subtitle track (I was told it did)...the MP4 shown is just a quicker (shorter) was of reproducing the same issue.

[icbaker]

Ah thanks - I'd misunderstood "loop a second time".

I can now reproduce. I can also reproduce the same behaviour without changing the repeat mode by seeking during the first playback.

I also noticed that at the end of the playback it doesn't fail/crash, the position keeps counting up beyond the end of the video suggesting it thinks there's still subtitle data to decoder.

I worked out it's related to this change (before this playback would fail immediately at the start of the first playback):
4107375

And specifically the fact that we set SimpleDecoder#exception = null in SimpleDecoder#flush() but if we've seen an error then the decoderThread has already exited, so all future calls to SimpleDecoder#queueInputBuffer() (and most other methods) don't throw an exception but also don't trigger any concrete decoding work. This means we never receive an end-of-stream signal, so the TextRenderer keeps playback alive (which is why the counter keeps counting up at the end).

I'll work on fixing this - thanks for reporting.

[icbaker]

This should now be fixed on dev-v2.