[MPlayer-users] Mplayer & DD5.1 via SPDIF - I have only DD2.0: why ?

Mon Dec 26 22:46:53 CET 2005

Hi all,

I have DIVX file with 5.1 sound, and I want to play it via MPLAYER.
My MythTV (R5A22) system is connected via digital SPDIF connection to my 
Home theater aplituner.

Launching mplayer with various parameters gives at best DD2.0 sound.
DD5.1 is impossible :-(
I spend literally days to trying solve this issue (many hours googilng & 
searching various forums)
System is: EPIA M10k, KnoppMythR5A22.
Used AVI file plays nicely DD5.1 under xine (unfortunately xine CPU 
consumption is about 50% vs 25% in mplayer. Also I have problem with AVI 
subtitles in xine)

Pls find below mplayer logs for different cmd line option used:

1. "mplayer -channels 6 -ao alsa -ac hwac3, file.avi"
Result: avi played 2 times too fast, amplituner connected to SPDIF shows 
no audio
Here is log:
------------------------------------------------------------------------------------------------------------------------------------
MPlayer 1.0pre6-3.3.5 (C) 2000-2004 MPlayer Team
CPU: IDT/Centaur/VIA C3 Nehemiah (Family: 6, Stepping: 5)
Detected cache-line size is 32 bytes
CPUflags:  MMX: 1 MMX2: 1 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 0
Compiled with runtime CPU detection - WARNING - this is not optimal!
To get best performance, recompile MPlayer with 
--disable-runtime-cpudetection.
Setting up LIRC support...
Playing Motorhead - Stage Fright 05'.avi.
AVI file format detected.
VIDEO:  [XVID]  592x320  12bpp  25.000 fps  1719.7 kbps (209.9 kbyte/s)
Clip info:
  Software: VirtualDubMod 1.5.10.1 (build 2439/release)
==========================================================================
Forced audio codec: hwac3
Opening audio decoder: [hwac3] AC3/DTS pass-through SP/DIF
hwac3: switched to AC3, 448000 bps, 48000 Hz
AUDIO: 48000 Hz, 2 ch, 16 bit (0x400), ratio: 56000->192000 (448.0 kbit)
Selected audio codec: [hwac3] afm:hwac3 (AC3 through SPDIF)
==========================================================================
vo: X11 running at 1024x768 with depth 24 and 32 bpp (":0.0" => local 
display)
==========================================================================
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Selected video codec: [ffodivx] vfm:ffmpeg (FFmpeg MPEG-4)
==========================================================================
Checking audio filter chain for 48000Hz/2ch/16bit -> 48000Hz/6ch/8bit...
AF_pre: af format: 2 bps, 2 ch, 48000 hz, big endian AC3
AF_pre: 48000Hz 2ch AC3
alsa-init: soundcard set to surround51
alsa: 48000 Hz/6 channels/12 bpf/61440 bytes buffer/Signed 16 bit Little 
Endian
AO: [alsa] 48000Hz 6ch AC3 (1 bps)
Building audio filter chain for 48000Hz/2ch/16bit -> 48000Hz/6ch/8bit...
Starting playback...
VDec: vo config request - 592 x 320 (preferred csp: Planar YV12)
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is 1.85:1 - prescaling to correct movie aspect.
VO: [xv] 592x320 => 592x320 Planar YV12
A:   0.3 V:   0.0 A-V:  0.320 ct:  0.000   1/  1 ??% ??% ??,?% 1 0
------------------------------------------------------------------------------------------------------------------------------------ 

2. "mplayer -channels 6 -ac hwac3, file.avi"
Result: avi played 2 times too fast, amplituner connected to SPDIF shows 
2.0 PCM 48kHz, sound is loud trash
Here is log:
---------------------------------------------------------------------------------------------------------------------------------
..................
Software: VirtualDubMod 1.5.10.1 (build 2439/release)
==========================================================================
Forced audio codec: hwac3
Opening audio decoder: [hwac3] AC3/DTS pass-through SP/DIF
hwac3: switched to AC3, 448000 bps, 48000 Hz
AUDIO: 48000 Hz, 2 ch, 16 bit (0x400), ratio: 56000->192000 (448.0 kbit)
Selected audio codec: [hwac3] afm:hwac3 (AC3 through SPDIF)
==========================================================================
vo: X11 running at 1024x768 with depth 24 and 32 bpp (":0.0" => local 
display)
==========================================================================
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Selected video codec: [ffodivx] vfm:ffmpeg (FFmpeg MPEG-4)
==========================================================================
Checking audio filter chain for 48000Hz/2ch/16bit -> 48000Hz/6ch/8bit...
AF_pre: af format: 2 bps, 2 ch, 48000 hz, big endian AC3
AF_pre: 48000Hz 2ch AC3
AO: [oss] 48000Hz 6ch Signed 16-bit (Little-Endian) (2 bps)
Building audio filter chain for 48000Hz/2ch/16bit -> 48000Hz/6ch/16bit...
Starting playback...
VDec: vo config request - 592 x 320 (preferred csp: Planar YV12)
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is 1.85:1 - prescaling to correct movie aspect.
VO: [xv] 592x320 => 592x320 Planar YV12
A:   0.4 V:   0.0 A-V:  0.352 ct:  0.000   1/  1 ??% ??% ??,?% 1 0       ---
---------------------------------------------------------------------------------------------------------------------------------

3. "mplayer -channels 6 -ao alsa file.avi"
Result: avi played OK, amplituner connected to SPDIF shows 2.0 PCM 
48kHz, audio is OK
Here is log:
---------------------------------------------------------------------------------------------------------------------------------
....................
Software: VirtualDubMod 1.5.10.1 (build 2439/release)
==========================================================================
Opening audio decoder: [liba52] AC3 decoding with liba52
AC3: 5.1 (3f+2r+lfe)  48000 Hz  448.0 kbit/s
AUDIO: 48000 Hz, 6 ch, 16 bit (0x10), ratio: 56000->576000 (448.0 kbit)
Selected audio codec: [a52] afm:liba52 (AC3-liba52)
==========================================================================
vo: X11 running at 1024x768 with depth 24 and 32 bpp (":0.0" => local 
display)
==========================================================================
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Selected video codec: [ffodivx] vfm:ffmpeg (FFmpeg MPEG-4)
==========================================================================
Checking audio filter chain for 48000Hz/6ch/16bit -> 48000Hz/6ch/16bit...
AF_pre: af format: 2 bps, 6 ch, 48000 hz, little endian signed int
AF_pre: 48000Hz 6ch Signed 16-bit (Little-Endian)
alsa-init: soundcard set to surround51
alsa: 48000 Hz/6 channels/12 bpf/61440 bytes buffer/Signed 16 bit Little 
Endian
AO: [alsa] 48000Hz 6ch Signed 16-bit (Little-Endian) (2 bps)
Building audio filter chain for 48000Hz/6ch/16bit -> 48000Hz/6ch/16bit...
Starting playback...
VDec: vo config request - 592 x 320 (preferred csp: Planar YV12)
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is 1.85:1 - prescaling to correct movie aspect.
VO: [xv] 592x320 => 592x320 Planar YV12
A:   0.1 V:   0.0 A-V:  0.107 ct:  0.000   1/  1 ??% ??% ??,?% 0 0 

---------------------------------------------------------------------------------------------------------------------------------

So now I'm confused:
"mplayer -channels 6 -ao alsa -ac hwac3, file.avi" gives "Opening audio 
decoder: [hwac3] AC3/DTS pass-through SP/DIF" but
"AUDIO: 48000 Hz, 2 ch, 16 bit (0x400), ratio: 56000->192000 (448.0 kbit)"
Later in log I see:
"................
Checking audio filter chain for 48000Hz/2ch/16bit -> 48000Hz/6ch/8bit...
AF_pre: af format: 2 bps, 2 ch, 48000 hz, big endian AC3
AF_pre: 48000Hz 2ch AC3
alsa-init: soundcard set to surround51
alsa: 48000 Hz/6 channels/12 bpf/61440 bytes buffer/Signed 16 bit Little 
Endian
AO: [alsa] 48000Hz 6ch AC3 (1 bps)
Building audio filter chain for 48000Hz/2ch/16bit -> 48000Hz/6ch/8bit...
................."
So what is current audio mode in mplayer and alsa: 6ch or 2ch ?

Oh the other hand, launching "mplayer -channels 6 -ao alsa file.avi" I get:
".....
Opening audio decoder: [liba52] AC3 decoding with liba52
AC3: 5.1 (3f+2r+lfe)  48000 Hz  448.0 kbit/s
AUDIO: 48000 Hz, 6 ch, 16 bit (0x10), ratio: 56000->576000 (448.0 kbit)
Selected audio codec: [a52] afm:liba52 (AC3-liba52)
...."
and later
".....
Checking audio filter chain for 48000Hz/6ch/16bit -> 48000Hz/6ch/16bit...
AF_pre: af format: 2 bps, 6 ch, 48000 hz, little endian signed int
AF_pre: 48000Hz 6ch Signed 16-bit (Little-Endian)
alsa-init: soundcard set to surround51
alsa: 48000 Hz/6 channels/12 bpf/61440 bytes buffer/Signed 16 bit Little 
Endian
AO: [alsa] 48000Hz 6ch Signed 16-bit (Little-Endian) (2 bps)
Building audio filter chain for 48000Hz/6ch/16bit -> 48000Hz/6ch/16bit...
....."
It looks like we have 6ch in alsa, but sound is DD2.0 - why ?