The VideoLAN Forums

Hi,
I got a couple of issues inside my free tvOS App (vuplusTV) using VLCKit, which currently is in beta for Version 1.1.

I have posted one issue about AC-3/Dolby Audio streams already in the "Development around libVLC" area - but it did not get any attention yet:https://forum.videolan.org/viewtopic.ph ... 93dc30345a
Maybe I get support now

Second issue is about playback of streams from encrypted TV Channel like SKY or HD+:
Several testers reported to me, that they get freezes every about 100 seconds, when playing back the streams. Other Apps and VLC on a PC do not have this issue. To make sure, the issue is not caused by the CI+ module (SKY V14, paired), I asked my testers to record a stream and check if playback of the recording shows the same issue. And it does on my App, other tvOS apps, that likely also use VLCKit or libVLC for playback. The recorded stream is not encrypted anymore, as it plays fine with VLC for PC after ftp'ing it to the PC - so the CI+ module is not required anymore.
Well, why always 100 seconds?
I asked if someone can share such a recording (TS file) for further analysis. Waiting for response now.

Third issue is about playback of recorded TS-Streams:
When trying to playback recorded streams via http from the STB, very often the playback starts without video, only Audio. Pausing playback and then continuing it works then, Video and Audio are fine then. This happens even with SD streams.
I use VLCKit for playback. I create an instance of VLCKit and set the media, which is a http URL. Then is (now) use parseWithOptions:6 and wait for the delegate callback didFinishParsing: before I send the play command in a background Thread with a brief delay. The delay helped a bit, but even a delay of up to 2 seconds does not solve it. The parsing state is 1 == completed, skipped.
I even tried to send play, pause and play with a brief delay, which does not solve this as well.
Any suggestion welcome.

I can share code snippets if this helps...

About second issue I will open a new thread, as VLC for tvOS shows the same behavior.
On my iPad (first Retina generation) the video does not run at all.

Well, the reason is that the TS are badly reencoded.

How can you prove that without having a look at it?
Indeed, VLC for Mac has no issues, VLC for tvOS has issues.
Kodi play them back fine, some others as well - just some VLCKit based do not?

And a dead lock (starting after 86 second and resuming after additional 86 seconds) looks quite strange... Dead locks should not happen.
Can you recommend any TS stream tool to evaluate your assumption?

How can you prove that without having a look at it?
Indeed, VLC for Mac has no issues, VLC for tvOS has issues.
Kodi play them back fine, some others as well - just some VLCKit based do not?

And a dead lock (starting after 86 second and resuming after additional 86 seconds) looks quite strange... Dead locks should not happen.
Can you recommend any TS stream tool to evaluate your assumption?

Show the logs. But this is similar to a different complaint with TS demuxer in 3.0

ok, how to get access to the logs created by VLC for tvOS?

You can enable debug logging on the VLCLibrary instance associated with your player instance.

OK, I can try that with my App - the log should be inside the Apps document folder - I will check.

How to access the log created by VLC for tvOS?

BTW: have you received the upload of the stream?

Cheers, SSB

As I tried to say, you need to do
to have VLC log everything to the normal Xcode or device console.

Sample was received and propagated to the respective engineer.

OK, I once did this. But how to enable it with VLC, when not having built it on my local Machine, but using the AppStore Version?
I will check the debug logs anyway

There is no way to enable debug logging for the VLC-iOS binary from the store.

OK, here we go with the log. I put some additional blank lines around the interesting part. Looks like the scramble state on 3 PIDs is changing from 0 -> 1 after 86 seconds and then back -> 0 after another 86 seconds.
Anyway I am still puzzled, why VLC on Mac or PC does not have this issue even it is the same file...

PS: sorry for the late reply, I also was busy

The nightly builds of VLC for Mac and PC will show the same behavior.

VLC 2.2 does not respect the scramble flag and 3.0 does. Not sure yet if this is a good idea though.

In general it could make sense to have the option to either ignore or respect the scramble flag to be backwards compatible.
And especially for use within my App - as the scramble flag is changing even nothing is scrambled - could be a bug in the STBs code or the CAM but we should try to get around this.

Make sense in which way ?
Trying to figure if the PES header sequence is a false positive and then all the *important* values of that header ? That's the point of ts scrambling flag.

There's currently a workaround if CAT is missing, as scrambling without CAT is nonsensical.
But don't expect that to be fixable if CAT is present.

Well, it makes sense for most users. They will really complain, when playback fails with new VLC while it plays fine with older versions. And when old version ignored the scramble flag and the new version does not, it also could be done optional - like adding a globally settable flag, if the scramble fields should get ignored.
And yes... let me check about the CAT. for sure the video does not need it, but maybe it still placed in the file. Making this workaround available as option (ignore CAT) would also solve the issue.

I am just afraid, that this might be part of contributed ffMpeg library and not inside the VLC part.

No, this parsing is done within VLC and not delegated to libavcodec.