LAV Audio Decoder

[hoborg]

I think LATM is what is used for HE-AAC in broadcast television, so that sample you already have is probably appropriate.

Then the problem is more complex.
LAV splitter output LATM as {000001FF-0000-0010-8000-00AA00389B71} and it is working.

MePo TS reader output it in same CLSID, graph is created, but no sound.

MS demultiplexer output LATM as {9A4BA8AE-83A0-4994-A670-12EC1E636F6A} - LAV audio decoder refuse connection.

[sub]

The media type create on the AAC pin can vary depending on the decoder you have selected. For example, with the Monogram AAC decoder it uses the media '{000001FF-0000-0010-8000-00AA00389B71}'. It sounds like I need to add a similar rule for the LAV decoder.

[sub]

Hmm, the LAV decoder wouldnt connect to the demux when I used {000001FF-0000-0010-8000-00AA00389B71}.

[hoborg]

The media type create on the AAC pin can vary depending on the decoder you have selected. For example, with the Monogram AAC decoder it uses the media '{000001FF-0000-0010-8000-00AA00389B71}'. It sounds like I need to add a similar rule for the LAV decoder.

Yes, i noticed it too. If i use DivX AAC decoder, it will use {000001FF-0000-0010-8000-00AA00389B71}.

[hoborg]

Hmm, the LAV decoder wouldnt connect to the demux when I used {000001FF-0000-0010-8000-00AA00389B71}.

It connect in MediaPortal (but they have it own TS reader), but there is no sound, so i think there is diferent problem - i think it have something to do with AAC parser in LAV splitter/ audio decoder.

[mvallevand]

If he has questions or needs samples let me know since I wrote a demuxer for the NMT and NPVR. LATM is a container that surrounds the AAC raw data, and how it is used varies, In the UK the LATM header is sent with every .ts block of packets with the NZ it can be may blocks away. The header is very important because it tells how many channels need to be output. The actual AAC data can be encoded many ways. It is normally AAC-LC (NZ, UK) but some countries us AAC-SBR

There is a Delphi .pas source/executable on the DVBViewer web site that remuxes HE-AAC to AAC and it works but I can't read Delphi well enough to figure it out. I had to write my decoder from the DVB spec.

Martin

[hoborg]

If he has questions or needs samples let me know since I wrote a demuxer for the NMT and NPVR. LATM is a container that surrounds the AAC raw data, and how it is used varies, In the UK the LATM header is sent with every .ts block of packets with the NZ it can be may blocks away. The header is very important because it tells how many channels need to be output. The actual AAC data can be encoded many ways. It is normally AAC-LC (NZ, UK) but some countries us AAC-SBR

There is a Delphi .pas source/executable on the DVBViewer web site that remuxes HE-AAC to AAC and it works but I can't read Delphi well enough to figure it out. I had to write my decoder from the DVB spec.

Martin

Well, if you think you can help nevcairiel, then you should contact him as soon as possible. If LAV audio decoder can handle all LATM AAC by using MS demultiplexer, there will be one audio decoder to handle all formats

[mvallevand]

I'm not that keen on anything more to do with HE-AAC. I did a lot of research and development getting it to work on the NMT but the demand from NextPVR users is just not there.

Martin

[Petrovski]

Is this GRF file any help? Automatically generated in Graphstudio when I load an NPVR UK Freeview HD recording. Plays the file perfectly in Graphstudio without modification yet NPVR plays it with no sound.

[shaunpatrick77]

Just an FYI, LAV 0.31 now available

http://forum.doom9.org/showthread.php?t=156191