Re: Having trouble extracting ac3 from dvd

On Wed, Feb 11, 2009 at 12:17:56PM +0100, Maik Holtkamp wrote:
> 0n 09/02/09@22:28 andrew told me:
> 
> > Using transcode 1.1.0 with no great skill I am attempting to extract
> > an ac3 stream directly from title 1, chapter 1 of a DVD. 

> > andrew@skamandros~$ transcode -x null,ac3 -i /dev/dvd -T1,1,1 \
> >-a 1 -A -y ac3 -o test.ac3
> 
> The syntax of -y is vmod[,amod]. Did you try -y null,ac3?

Thanks for that, and I apologise or misunderstanding the basics.
However for ac3 Transcode 1.1.0 does not like that syntax:

transcode -x dvd -i /dev/dvd -T 1,3,1 -a 0 -y null,ac3 \
-E 48000 -m $HOME/Desktop/test.ac3

with the error message:

[import_dvd.so] waiting...
[import_dvd.so] waiting...
[export_ac3.so] warning: *** This module is non-optimal ***
[export_ac3.so] warning: *** Use -N 0x2000 instead of -y ...,ac3
(faster) ***
[export_ac3.so] ffmpeg -y -f s16le -ac 2 -ar 48000 -i - -ab 128
-acodec ac3 /home/andrew/Desktop/test.ac3 >/dev/null 2>&1

Leaving a zero byte file. I experimented with the suggested syntax a
little:

transcode -x null,dvd -i /dev/dvd -T 1,3,1 -a 0 -N 0x2000 \
-E 48000 -m $HOME/Desktop/test.ac3

But while this imported well enough it did not export:

[transcode] V: auto-probing     | /dev/dvd (OK)
[transcode] V: import format    | MPEG 2 program stream in DVD PAL
(module=null)
[transcode] A: auto-probing     | /dev/dvd (OK)
[transcode] A: import format    | AC3 in DVD PAL (module=dvd)
[transcode] V: AV demux/sync    | (1) sync AV at initial MPEG sequence
[transcode] V: import frame     | disabled
[transcode] V: bits/pixel       | 0.000 (unknown)
[transcode] V: decoding fps,frc | 25.000,3
[transcode] V: video format     | YUV420 (4:2:0) aka I420
[transcode] A: import format    | 0x2000  AC3          [48000,16,2]
[transcode] A: export           | disabled
[transcode] V: encoding fps,frc | 25.000,3
[transcode] A: language         | en
[transcode] A: bytes per frame  | 7680 (7680.000000)
[transcode] A: adjustment       | 0@1000
[transcode] V: IA32/AMD64 accel | sse3 sse2 sse mmx cmove asm 
[transcode] V: video buffer     | 10 @ 0x0 [0x2]
[transcode] A: audio buffer     | 10 @ 48000x2x16
[import_dvd.so] v0.4.1 (2007-07-15) (video) DVD | (audio) MPEG/AC3/PCM
[import_null.so] v0.2.0 (2002-01-19) (video) null | (audio) null
[export_null.so] v0.1.2 (2001-08-17) (video) null | (audio) null

so obviously I have this all upside down. I was tossing up whether to
recompile and enable deprecated syntax but I am keen to learn the
correct, newer syntax.

Andrew

-- 
Do you think that's air you're breathing?