Live TV crash

[Adam Bennetts <abennetts@…>]

Live TV crashes the front end if Live TV is started with time stretch set to 120.

To reproduce:

1. In Setup, Video, Playback Groups, Default, set the time stretch value to 120.
2. Start Live TV.
3. The front end crashes without playing any live TV.
4. Change the time stretch back to 100 and Live TV works.

My MythTV frontend log with additional logging is attached.

I'm not able to create a backtrace right now but expect to be able to within the week if needed.

[Adam Bennetts <abennetts@…>]

Frontend log

[Adam Bennetts <abennetts@…>]

MythTV version info

[J.Pilk@…]

Where is it supposed to get the data from? It hasn't been transmitted yet.

[Adam Bennetts <abennetts@…>]

Replying to J.Pilk@…:

Where is it supposed to get the data from? It hasn't been transmitted yet.

Of course. I think the front end should drop time stretch back to 100 and continue. This is what 0.24 did for me. I'm pretty sure 0.24 also did this if you had paused live TV and then caught up using time stretch - time stretch was reduced to 100 once there was no more data. 0.25 playback stutters as it waits for more data and then speeds up and then stutters etc (although possibly a different bug and I haven't tested it much, it may be related).

Possibly I should configure my playback groups differently and not set time stretch to > 100 in the Default play back group (I use default for everything, rightly or wrongly). But even then I don't think (mis) configuring time stretch should be able to crash the front end.

Cheers, Adam.

[J.Pilk@…]

Agreed: but a /real/ fix could be quite profitable...

[stichnot]

Backtrace from a mythfrontend build with various patches; line numbers may vary

[Jean-Yves Avenard <jyavenard@…>]

In 343e658ee65f6355de87ad0da0c4b57059d80bac/mythtv:

Abort setting timestretch if audio hasn't been initialised yet.

When starting liveTV with timestretch already set, it would cause an uncatched exception error.
Why mythplayer is calling SetStretchFactor? is a mystery to me and needs to be investigated. In the mean time, abort if the number of audio channels is invalid.

Fixes #10612

[Jean-Yves Avenard <jyavenard@…>]

In e20d1f8e6cb33e7435ba57b25e0e72d6a16c56cd/mythtv:

Abort setting timestretch if audio hasn't been initialised yet.

When starting liveTV with timestretch already set, it would cause an uncatched exception error.
Why mythplayer is calling SetStretchFactor? is a mystery to me and needs to be investigated. In the mean time, abort if the number of audio channels is invalid.

Fixes #10612

[cherry-picked from 343e658ee65f6355de87ad0da0c4b57059d80bac]

[Jean-Yves Avenard <jyavenard@…>]

In c2fccb545d02808b3d16fb73f52aa92ea75ea719/mythtv:

Make sure passthru flag is in sync between video decoder and audio framework

When entering LiveTV with timestretch enabled via playback group, audio would be broken if watching a channel with AC3 content.
Reason being, audio is set for timestretch, but digital passthrough isn't disabled. We now make sure digital passthrough is disabled should timestretch had been activated earlier on.

Additionally, add the ability to cancel timestretch and audio processing should we revert to a timestretch factor of 1.0. This will only work if no reconfigure is done in between.

Fixes #10612 part 2

[Jean-Yves Avenard <jyavenard@…>]

In f6e16c4fb14e22232f08d8b826c6186705e41ffc/mythtv:

Make sure passthru flag is in sync between video decoder and audio framework

When entering LiveTV with timestretch enabled via playback group, audio would be broken if watching a channel with AC3 content.
Reason being, audio is set for timestretch, but digital passthrough isn't disabled. We now make sure digital passthrough is disabled should timestretch had been activated earlier on.

Additionally, add the ability to cancel timestretch and audio processing should we revert to a timestretch factor of 1.0. This will only work if no reconfigure is done in between.

Fixes #10612 part 2

[cherry-picked from c2fccb545d02808b3d16fb73f52aa92ea75ea719]