Bug 1608

Summary:	lavcac3enc filter not working anymore
Product:	Mageia	Reporter:	Chris Denice <eatdirt>
Component:	RPM Packages	Assignee:	Mageia Bug Squad <bugsquad>
Status:	RESOLVED FIXED	QA Contact:
Severity:	normal
Priority:	Normal	CC:	marja11, philippedidier, stormi-mageia
Version:	1
Target Milestone:	---
Hardware:	x86_64
OS:	Linux
Whiteboard:
Source RPM:	mplayer-1.0-1.rc4.0.r32713.5.mga1.tainted.src.rpm	CVE:
Status comment:

Description Chris Denice 2011-06-05 16:53:52 CEST

Description of problem:

Hi,
I used to use mplayer to encode on the fly AAC stream (radio or movie) and pass them through spdif output to get my AC3 amplifier decoding the final stream.

In command line argument, this is achieved with the filter:

"-af lavcac3enc=1"

or, taking radioparadise stream as an input as:

mplayer -ac hwac3 -ao alsa:device=hw=1.1 -channels 6 -af lavcac3enc=1  http://scfire-dtc-aa03.stream.aol.com:80/stream/1049

Now I get this error:

AAC file format detected.
==========================================================================
Forced audio codec: hwac3
Cannot find codec for audio format 0x4134504D.
Audio: no sound


Which means that the AAC stream is not encoded into AC#, hence the "cannot find codec for audio" error. The AAC is indeed properly decoded since this command works (note the comma afer hwac3 which implies to look to other codecs if the first fails)

mplayer -ac hwac3, -ao alsa:device=hw=1.1 -channels 6 -af lavcac3enc=1  http://scfire-dtc-aa03.stream.aol.com:80/stream/1049


AAC file format detected.
==========================================================================
Forced audio codec: hwac3
Trying to force audio codec driver family libmad...
Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
AUDIO: 44100 Hz, 2 ch, s16le, 0.0 kbit/0.00% (ratio: 0->176400)
Selected audio codec: [ffaac] afm: ffmpeg (FFmpeg AAC (MPEG-2/MPEG-4 Audio))
==========================================================================


It looks that the line "-af lavcac3enc=1" is simply ignored. I tested with various streams, videos that used to work on mandriva, but I got into the same problem. It does not seems that some codec are missing, I am also able to decode pure AC3 streams also.

Cheers,
Chris.

Comment 1 Samuel Verschelde 2011-10-01 15:25:00 CEST

faac is not in the repos because of licence + legal issues (impossible to put it in non-free media because of legal issues, and impossible to put it into tainted media because it's non free, we will try to find a way to integrate it for Mageia 2.

Could it explain your problem?

CC: (none) => stormi

Comment 2 Philippe Didier 2011-10-01 21:25:17 CEST

On Mandriva you may have used the mplayer and mencoder rpm from plf repo : it was built with faac and lame provided by plf too..

In Mandriva repo faac and lame were not provided, and mplayer was built without faac and lame, and not able to encode audiofiles to ac3 nor mp3 format 

Both version use faad : you may always decode an aac file (and encode it to wav for example)


In Mageia core : mplayer can read aac or mp3 but not encode to mp3 or aac format
(like in mandriva)
In mageia tainted : mplayer can read both of them too and can encode to mp3 but not aac

We need a special repo for faac

This bug is linked to bug 2771 (not exactly a duplicate) and so to bug 2833

CC: (none) => philippedidier

Comment 3 Chris Denice 2011-10-02 11:55:31 CEST

Thanks for the info guys! I have no attentively followed the discussion about faac indeed.

Cheers.

Comment 4 Marja Van Waes 2011-12-04 09:04:11 CET

(In reply to comment #1)
> faac is not in the repos because of licence + legal issues (impossible to put
> it in non-free media because of legal issues, and impossible to put it into
> tainted media because it's non free, we will try to find a way to integrate it
> for Mageia 2.
> 
@ Samuel (or anyone who knows):

I didn't follow the discussion (if it is still going on) and I don't even know when the policy review will be or was.
Can you give some recent information?

CC: (none) => marja11

Comment 5 Chris Denice 2011-12-04 14:00:04 CET

Hi there,
everything works now like a charm, you can close the bug. The required drivers are found with the tainted repository.

For information, the above example needed a bit more tuning: lavcac3enc should be set to 1:128:2; 128 is the bit rate, 2 the number of channel under which the encoder is skipped (by default this is 5, so without the 2, it never works for stereo streams).

So, radio paradise in Dolby Digital is:

mplayer -ac hwac3, -ao alsa:device=hw=1.1 -af lavcac3enc=1:128:2 
http://scfire-dtc-aa03.stream.aol.com:80/stream/1049

:)

Chris.

Comment 6 Marja Van Waes 2011-12-04 16:18:45 CET

(In reply to comment #5)
> Hi there,
> everything works now like a charm, you can close the bug. The required drivers
> are found with the tainted repository.
> 

Thanks for letting us know, Chris :D

Status: NEW => RESOLVED
Resolution: (none) => FIXED