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Hello!

In Norway they've started sending H.264 with AAC-HE sound over DVB-T.
The problem is that I'm not able to get any sound in VLC. Video is displayed correctly,but the audio is missing. I've put two sample clips here if anyone can have a look at them. The first clip is a complete PID capture of Video+Audio (About 30MB.) The second one is a radio station PID. (Only 128Kb). I can't get sound either way.

Clip 1: http://www.sendspace.com/file/oej1fj
Clip 2: http://www.sendspace.com/file/0shilp


Thanks

I can't get audio either. In any player!

Mplayer reports this:

FAAD: error: Channel coupling not yet implemented, trying to resync!
FAAD: error: Invalid number of channels, trying to resync!
FAAD: error: Maximum number of scalefactor bands exceeded, trying to resync!
FAAD: error: Invalid number of channels, trying to resync!

VLC reports this:

packetizer_mpeg4audio debug: emulated sync word (no sync on following frame)

MPC would load the file using it's internal AAC codec but also would not play audio.

I have 2 Direct Show AAC codecs but graphedit would not connect to either one for audio.

The video and subs work well in VLC.

It's possible to demux the aac stream from the TS using DGIndex.
It will play in WinAmp if you give the file the .aac extension.
However, if I try to play the aac file in VLC it thinks it's a mp3 file

main debug: creating demux: access='' demux='' path='C:\Video\nrk_aac-he2 aac'
main debug: looking for demux2 module: 45 candidates
ts warning: TS module discarded (lost sync)
ffmpeg debug: detected format: mp3
ffmpeg error: av_find_stream_info failed
ps error: cannot peek
vobsub debug: could not read vobsub IDX file
main error: no suitable demux module for `/://C:\Video\nrk_aac-he2 aac'
main debug: removing module "access_file"
main debug: thread times: real 0m0.180259s, kernel 0m0.000000s, user 0m0.060086s
main debug: thread 4044 joined (input/input.c:412)
main warning: unable to find parent!
main: nothing to play

WinAmp will show the following info about the file:
MPEG info:
Size: 119128 bytes
Format: AAC
MPEG-4 HE-AAC (Implicitly Signalled)
Sample Rate: 24000 (Output: 48000)
SBR: Present
Channels: 2 Mode: Stereo
Bitrate: VBR (0)


So.... what do u devs say

I think you should use Winamp for these files as NO other standards based players or codecs will play these files.

Even Winamp shouldn't be reporting "Bitrate: VBR (0)"

So the question is... What's wrong with the stream? This is a pure capture taken from the official Norwegian DVB-T broadcast. This is the format that they're using... I might be a wierdo, but I like to watch the TV broadcast live. Right now it's not possible since VLC does not understand the stream. As far as I know aac can be in either a mp4 container, in ADTS frames or in pure RAW format without any headers. Is this what we have here? Still I think that there's something wrong with VLC when it thinks that it's a mp3 stream. After all WinAMP is STILL able to play it without any problems.

Winamp is the program that diversified AAC so others may not or will not play it. Personally I would be happy if the channel mapping for 5.1 and fold down to stereo were fixed in any DECODER.

So write a letter the the TV network asking them to use Nero's encoder or for that matter anyone else's encoder except Winamp. In this way other players will have a chance to decode the broadcast other than just winamp.

The discussion from here http://www.hydrogenaudio.org/forums/ind ... opic=55232 could be from interest (only to your information).

The "raw" AAC data is usually in LATM/LOAS format, faad2 can't decode that. Winamp can.