Cypheros Transportstream Forum

English-speaking Support => Specific problems with recordings of satellite/cable receivers => Thema gestartet von: Lost Kahuna am März 11, 2014, 22:47:10

Titel: Audio missing from the converted MP4 file
Beitrag von: Lost Kahuna am März 11, 2014, 22:47:10
I am trying TS Doctor to manipulate HD TS files recorded on a Humax Freeview box in the UK.  TS Doctor can read these files and split them - no problem. I tried to convert them with the "TS Format Converter". I was impressed to watch the speed of conversion. Unfortunately, the output file did not contain any audio channels. What exactly am I missing here?

TS-DOCTOR: 1.2.108
Export all audio streams for MP4: ticked
LAVFilters: 0.60.1.0
Haali-Splitter: 1.13.138
tsMuxeR: 2.0.8(b). www.networkoptix.com
Titel: Re: Audio missing from the converted MP4 file
Beitrag von: Djfe am März 12, 2014, 14:31:47
first: try to switch to the newest beta (.111) (normally all the betas are save from faults and there have been small issues in not beta versions as well, so I doesn't make to much difference except more bug fixes in the beta)
download the newest tsmuxer (.11)
the newest lav-filter (.61)

the reason why the "converting" works faster is that the video stream doesn't get reencoded
the streams are only repacked (remuxed is the technical term)
so if there are errors in the stream they will be in the new stream as well (if you reencode you will still have the artifacts if there were some in the original file but the video stream will be decodeable without any problem)

it is possible that the remuxer has issues converting your file so after you updated your tools and tried it again:
pls upload two logs here: the *_check.log (just check the file) and the remux log (remux the file again)
maybe you need to activate logs in the options first: just check the checkbox for this on the first settings page
Titel: Re: Audio missing from the converted MP4 file
Beitrag von: Lost Kahuna am März 13, 2014, 23:32:50
Thank you very much for your reply. I switched to the new beta (1.2.112) and updated the plugins as you suggested. I checked and converted a HD TS file.  It has one video channel, two audio channels and one for subtitle. The TS Format Converter only preserves the video.  The check log did not find any error in the stream though.

I am not sure how I can create the remux log. Don't see any log created after the MP4 conversion.
Titel: Re: Audio missing from the converted MP4 file
Beitrag von: Mam am März 14, 2014, 07:21:21
Although my answer does not actually solve your problem, but maybe it gives a hint why programs are choking on your recording.

Your log shows quite many changes in video format. It constantly flips between 1920x1088 progressive to 1920x1088 interlaced (and back of course).

There is no 1920x1088 progressive format on Tvs currently, it simply does not exist (because of limited bandwidth and too slow speed) !
So these format changes must be a kind of error or a kind of misinterpretation of your data by the Doctor.

Maybe this also has influence on the treatment of the audio channels.

The log shows that audio and subtitle channels are written, 130Mb for AC3-2.0 even sounds like a reasonable size for a 90mins movie. The other audio only has 33Mb, that is very short, maybe really bad quality?

So the sound is in your resulting file, if it does not show up in your player/next program you use in converting process, you could try to remux it (eg with mkvtoolnix) into a different format and see if things turn out better.

I would assume you should contact the Programmer here and upload your recording to his ftp server. He can analyse your file more detailed and maybe the next version of the program works better with your files.
(I've also noticed that the TSD does not really work very well with english channels. Sometimes it is much too picky in what it calls an error and sometimes (like cutting BBC) it produces bad artifacts.)
Titel: Re: Audio missing from the converted MP4 file
Beitrag von: Cypheros am März 14, 2014, 09:34:44
Mam is right, it looks like your recording has a special encoding format TS-Doctor doesn't know. A short sample of such a recording could help to analyse the problem and fix it in the next update.
Titel: Re: Audio missing from the converted MP4 file
Beitrag von: Lost Kahuna am März 14, 2014, 13:02:33
Thank you very much for your replies.  Please let me know the FTP server details so I can upload a small portion of a sample.  Presumably, you want me to cut 10 or 20 MB from the front.

Incidentally, I started my career as a C++ programmer in Multimedia in the 90's!  Unfortunately, I don't do anything exciting anymore [just boring financial software management] but I am not completely unfamiliar with getting my hands dirty in the low-level file headers and structures.  So you want me to run some diagnostic tools to extract headers, etc. I believe I can still do this.
Titel: Re: Audio missing from the converted MP4 file
Beitrag von: Cypheros am März 15, 2014, 14:52:45
Thanks for the sample. It's very interesting to see this special stream details. There are some strange settings. Video interlaced mode is changing and aac audio has LATM format. LATM is unsupported by most of the video tools I tested.

TS-Doctor can convert AAC LATM to AAC ADTS using TS-Remuxer from the tools menu. Make sure you have activated the converter:
[attachimg=1]

But even that will not help to get the file converted correctly. There are more things I have to investigate.


Titel: Re: Audio missing from the converted MP4 file
Beitrag von: Lost Kahuna am März 15, 2014, 18:42:47
Yes - you are right. I have that option [LATM -> ADTS] switched on but that didn't help the conversion.  I guess you have to write a new stream decoder if you wish to support these UK Freeview HD channels.

I am not sure if all TV stations are using the same format or there exist minor variations in their signals. I have a mechanism to decrypt DVB-T and DVB-T2 signals. Please let me know if you need to see more samples, especially from other TV stations.

Unfortunately, I am not aware of any technique to decrypt DVB-S2 signals!
Titel: Re: Audio missing from the converted MP4 file
Beitrag von: Cypheros am März 15, 2014, 23:33:55
At the moment TS-Doctor is using Haali muxer to create MP4 files but Haali is not accepting the AAC audio stream. Other tools like mp4box or tsmuxer aren't working either.

I'm trying to find another solution for converting this kind of files to mp4.

Samples of other channels would be great to improve support for British tv.
Titel: Re: Audio missing from the converted MP4 file
Beitrag von: Lost Kahuna am März 23, 2014, 12:49:26
I uploaded two samples last night from two different channels.  Please let me know if you spot any difference in the file structure.

I see there is a new beta available. Should I expect any improvement in this beta for MP4 conversion?
Titel: Re: Audio missing from the converted MP4 file
Beitrag von: Cypheros am März 25, 2014, 00:33:04
Thanks for the samples. No the new version has no fix for creating MP4s from BBC sources. But I'm working on a mp4 muxer to create valid mp4 files.