LAV Filters - DirectShow Media Splitter and Decoders

[Ger]

This thread is very welcome news.

I've prepared a batch of 6 TS samples recorded from different Scandinavian DVB channels and one feed, highlighting a few issues. Not all issues are directly splitter related, but I thought I'd include everything for reference. May be useful.

In addition to the samples, there are some screenshots included from other players (VLC and DVBViewer) explaining what is correct and what is wrong.

There is also a text file with further explanations of common issues and of each individual sample, with results from my tests with various splitters/decoders/players.

Some bugs and missing features are also pointed out in the internal MPC-HC and ffdshow H264 DXVA decoders and the MPC-HC MPEG-2 decoder and DVB-subtitle renderer (and even a few issues in Haali splitter, VLC and DVBViewer). If other MPC-HC devs (or the project manager) wants to download the samples to look at these decoder/subtitle issues, please do so. I have not posted any of these issues (including the splitter issues) to the bug tracker yet (I just finished writing this up and recording samples today). So unless someone else have already posted these bugs with different samples, they are not there. I will try to add them there eventually, but I don't know yet when I'll have time for that. So feel free to grab the samples and/or add your own bug reports/tickets in the meantime.

All TS recordings seem to have one important issue in common with the new LAVFSplitter: The duration is wrong (example: the HD sample is reported as over an hour long, but is just over a minute in reality) and the MPC-HC slider doesn't work. Probably related issues.

Most other splitter issues are subtitle related, one is audio related, and there are some aspect ratio issues.

I haven't really tested the responsiveness (when skipping etc.) compared to Haali/Gabest splitters yet because of the freezing issues in v0.3, and the fact that the slider isn't working yet, so I'll save that for another day.

Sharebee 145 MB multipart rars: Part1 - Part2 - Part3
or
Megaupload single 340 MB file: TS-Samples-2010-08-18.rar

All LAVFSplitter tests are with version 0.3. BTW thanks for fixing the freeze issue in 0.4 which was admittedly a little annoying during the testing.

Anyway, good luck with the new splitter. Hopefully everything you need to know about the samples is explained in the screenshots and the text file. Feel free to ask if it isn't or if you need more samples/testing.

Edit: Didn't see Underground78's post when i posted, but it seems to address some of the same issues.

Edit2: Made a copy/paste mistake in the text file. The test results for the 4:2:2 sample was wrong (that particular sample is not splitter related or aspect ratio related - only a comparison of MPEG-2 decoders, if they support MPEG-2_422 or not). Fixed text file (only) here. Will also re-upload a full sample pack with the fixed text file, but it will take a few hours.

Edit3: Replaced the single rar zshare file with a multipart rar on Sharebee (fixed text included). Also a single file Megaupload alternative.

[nevcairiel]

Originally Posted by STaRGaZeR

Now, if just after opening the sample I switch to the PGS track, PGS subs look fine. But again, if I switch to the SRT track, nothing will appear. Stream switching bug here it seems.

This is weird. The splitter does send the new media type in the next packet after the switch, which the filter should pick up and act accordingly. I'll test this, i don't think i actually had a sample with different sub types before, so thanks!

Originally Posted by Underground78

[MPEG PS/TS/PVA Splitter] Switching between audio tracks is not immediate. The bug report is also valid with LAVFSplitter 0.4, switching between the audio tracks takes much more time than it does when playing with VLC.

Fixed this, a silly bug was breaking proper audio stream switching. It'll now stop the graph and reconnect the audio filter, so that media type changes are handled properly. This will however cause a brief interruption of playback - but then, you don't change audio streams while watching, you change them once and then watch.

For the broken seeking, i don't know.
If the duration is reported wrong, its a bug in libavformat itself, and would explain the broken seeking.
I can imagine this happening with files that were cut out of a big file. Are your samples out of a file that had the original length before, by any chance?

[Underground78]

Originally Posted by nevcairiel

Fixed this, a silly bug was breaking proper audio stream switching. It'll now stop the graph and reconnect the audio filter, so that media type changes are handled properly. This will however cause a brief interruption of playback - but then, you don't change audio streams while watching, you change them once and then watch.

Thank you for looking at this !

Originally Posted by nevcairiel

For the broken seeking, i don't know.
If the duration is reported wrong, its a bug in libavformat itself, and would explain the broken seeking.
I can imagine this happening with files that were cut out of a big file. Are your samples out of a file that had the original length before, by any chance?

Well all the TS files I deal with are DVB-T captures but MPC-HC internal splitter does report the correct length for the sample #327 for example.

[hoborg]

Updated with 0.8
Hi.
i did some more test with 0.8.

Some FLV cannot be split, they have blackscreen or play at wrong speed (noticed if they are VBR based) All of them working fine using Cyberlink FLV spliter, VBR problem can be reproduced if MPC FLV splitter is in use.

Some MPG files not working corectly, there are coruption on begin or they fail to start playback (no such problems when using "MPC - Mpeg Splitter (Gabest)"
Coruption:


All problematic samples can be downloaded here.

[STaRGaZeR]

Originally Posted by nevcairiel

This is weird. The splitter does send the new media type in the next packet after the switch, which the filter should pick up and act accordingly. I'll test this, i don't think i actually had a sample with different sub types before, so thanks!

Do you stop the graph and reconnect when switching subtitles like you do now with audio? That would ensure proper handling of the new format. Haali does this for all kind of tracks right?

[nevcairiel]

Originally Posted by STaRGaZeR

Do you stop the graph and reconnect when switching subtitles like you do now with audio? That would ensure proper handling of the new format. Haali does this for all kind of tracks right?

I tried to do this, but there were complications, so currently its not doing this. Its basically doing what the gabest Mpeg splitter does, it just sends the new pin media type and starts sending new data.

Its on my list to try to get to work again.

[STaRGaZeR]

I think that's the best solution. Changing the media type and wait for the decoder to adapt itself is just asking for trouble. It could work with one filter but not with another. Thanks for looking into it

[Ger]

Originally Posted by nevcairiel

For the broken seeking, i don't know.
If the duration is reported wrong, its a bug in libavformat itself, and would explain the broken seeking.
I can imagine this happening with files that were cut out of a big file. Are your samples out of a file that had the original length before, by any chance?

All six samples I posted are recorded "as is" from regular TV-channels (plus one 4:2:2 feed), either using Dreambox or DVBViewer. None of them are cut or treated in any way after recording. So they should be "run of the mill" TS files in that sense.

All are reported as zero-length in MPC-HC+LAVFsplitter 0.4, except the HD sample which is reported as over an hour long when it's actually just over a minute.

The slider does work on the HD sample, but is still wrong because it thinks the clip is much longer than it is, so yes, I'm pretty sure the slider will fix itself for all samples once the duration is corrected. Feel free to use my samples as you wish, if you want to pass some upstream to libavformat devs.

Gabest/Haali/Mediainfo all get the duration right, but Haali also gets other stuff (ie. aspect ratio) right more often than Gabest. Haali has a default setting set to scan 45000 TS packets, which seems to work well, but don't how relevant that is.

[nevcairiel]

Originally Posted by STaRGaZeR

I think that's the best solution. Changing the media type and wait for the decoder to adapt itself is just asking for trouble. It could work with one filter but not with another. Thanks for looking into it

Well, audio is a bit different in that regard, as the audio decoder filter can change between streams. So i delete it and let the GraphBuilder rebuild the graph.

Now with subtitles and ffdshow.. I can't do the same, as ffdshow is also the video decoder, and deleting that one isn't working out too good. But then, i don't really have to, as basically all subtitle renderers i know are used for all kinds of subtitles. So i'll see if i can just disconnect the pin and cause a reconnect that will make the filter initialize itself again without doing the full delete magic.

Sadly this area isn't really covered by any documentation i found, and all other splitters that seem to handles this properly are closed source, so bear with me while i try different approaches. =)

[nevcairiel]

I found the problem with TS file durations, was kinda a "oops" on my side, heh.
And like expected seeking is working fine with the proper durations.

@Ger:
Man that zSHARE page is a mess.
Still downloading.... previously it just stopped at 20% or so and i had to restart. If it does that again, screw it =P
How about splitting the files and uploading to rapidshare or something?

[Underground78]

Originally Posted by nevcairiel

I found the problem with TS file durations, was kinda a "oops" on my side, heh.
And like expected seeking is working fine with the proper durations.

Great !

[Ger]

Originally Posted by nevcairiel

I found the problem with TS file durations, was kinda a "oops" on my side, heh.
And like expected seeking is working fine with the proper durations.

Great.

@Ger:
Man that zSHARE page is a mess.
Still downloading.... previously it just stopped at 20% or so and i had to restart. If it does that again, screw it =P
How about splitting the files and uploading to rapidshare or something?

I'll try to create multipart rars < 150 MB or something like that, and upload to sharebee (which should distribute to several other services). But it will take a few hours because of my slow upload speed.

[nevcairiel]

Originally Posted by Ger

I'll try to create multipart rars < 150 MB or something like that, and upload to sharebee (which should distribute to several other services). But it will take a few hours because of my slow upload speed.

I finished the download now, so don't worry about it.

Regarding your files:

LATM AAC is not supported by libavformat at all right now, someone will have to implement this, so no deal on audio. Trying to get subtitles to work, but ffdshow subtitle renderer doesnt even connect to the DVB subtitles, wonder if MPC does..

[Ger]

MPC-HC does show DVB-subs (Casimir added this not too long ago IIRC) with the internal splitter, but wrong background color (green instead of semi-transparent grey in the John Adams sample). That is probably not a splitter issue though. DVB subs with a fully transparent background (Bulgarian etc. in the Henry IV sample) seems OK with internal splitter/renderer (not tested thoroughly though).

TTX subs probably need a Teletext decoder, which I doubt MPC-HC has currently, but it would be nice if the splitter identified both the DVB and TTX subtitle tracks correctly anyway.

[nevcairiel]

I'm just having it ignore TTX for now, as i don't really know what to do with them.

EDIT:
DVB subs work, yay.
Now i just need to find the difference in the flags for your hearing impaired thing and i'm all done.

EDIT2:
Ok, i arrived at that sample with subs in both DVB and TTX, but how exactly am i supposed to figure out if its a TTX sub or some other TTX stream that i don't want to show?
This puzzles me! For now i'm just showing the 3 DVB sub tracks.

[tetsuo55]

You guys could use megaupload.com in the future, it offers a high upload and download speed and supports files up to 1gb iirc

[Ger]

Originally Posted by nevcairiel

EDIT2:
Ok, i arrived at that sample with subs in both DVB and TTX, but how exactly am i supposed to figure out if its a TTX sub or some other TTX stream that i don't want to show?
This puzzles me! For now i'm just showing the 3 DVB sub tracks.

It's over my head, but if you look at the "Whatever works" sample in VLC, or the screenshot I've included, VLC can tell the difference between TTX index pages and TTX subtitles with a valid language code. So perhaps you can peek at the VLC code? Unless a teletext decoder is required for that part (I have no clue).

@Tetsou55
Thanks. I'll try to remember that for future use.

[STaRGaZeR]

Originally Posted by nevcairiel

so bear with me while i try different approaches. =)

Ofc

Originally Posted by nevcairiel

but ffdshow subtitle renderer doesnt even connect to the DVB subtitles, wonder if MPC does..

ffdshow doesn't support DVB subs, MPC does.

[naomatrix]

Thank you for the splitter , great job.

Stuffed in a Pot 1.5.23507Ru place MKV / WebM, AVI, MP4/MOV, TS/M2TS/MPG, FLV, drove on the test files at 1080p (720p) BDrip everything seems Ok
Of course there is for 0.4 versions are still drawbacks - no graphical interface, yet buggy to switch audio and subtitle roads, more slowly shifts.
But there is a big plus, correctly sees and connects the sound of the road (TrueHD, DTS MA), as well, and I'm very pleased so far the world's only splitter that correctly identifies the audio format AAC + + HEv2 SBR PS 2ch (5.1ch). Believe me I've tried a lot of splitters and decoders AAC (6 pieces) all spoke HE SBR 2ch PS (parametric stereo) as mono, only LAVFSplitter correctly identifies.

Good luck

[Ger]

I did some digging, and don't take my word for it (my understanding is limited), but there may be something of interest here:

Regarding the hearing impaired flags in DVB-subs: Page 38 and 73.
Teletext subs vs non-subs: Page 8.

Both found here.

If that doesn't help, I guess VLC git or Enigma2 git.