[MPlayer-users] DTS and Dolby Digital passthrough works for VOB but not AVI files

Steve Vanspall steve at vanspall.id.au
Sat Nov 24 09:31:55 CET 2007


Hi,

I have a Sound Blaster live card with SPDIF Digital Out and passthrough 
capabilities.

I use Mplayer to play video's in mythtv using the following command line 
options.

mplayer -ao alsa:device=iec958 -fs [video_file]

Now I know when the digital signal is being passed through properly 
because my receiver lights up with Dolby Digital or DTS.

To test this out I have a set of Xvid's with Dolby Digital and DTS 
encoded sounds. Infact they are those DD/DTS intros you see before a 
movie sometimes.

After encoding the xvids (from vob files) I double checked the audio 
encoding and sure enough they still read as Dolby Digital or DTS.

Now the problem I have is that these Xvid encoded avi's do not pass 
through the digital signal.

So I had the idea of trying to play the original vob files. so I played 
one Dolby Digital fiel and one DTS file. Sure enough both these files 
registered correctly on my receiver. So passthough works just not with 
AVI's.

Can anyone suggest why?

belowis the output for the dts files. The first is the Xvid file (the 
one that doesn't pass through dts signal) the second the original vob 
file (the one that works).

Any help would be appreciated

Steve

-------------------------
mplayer -ao alsa:device=iec958 -fs dts_digitalexperience.avi

AVI file format detected.
VIDEO:  [XVID]  720x416  12bpp  25.000 fps  2894.8 kbps (353.4 kbyte/s)
Clip info:
 Software: VirtualDubMod 1.5.4.1 (build 2178/release)
xscreensaver_disable: Could not find XScreenSaver window.
GNOME screensaver disabled
==========================================================================
Opening video decoder: [ffmpeg] FFmpeg's libavcodec codec family
Selected video codec: [ffodivx] vfm: ffmpeg (FFmpeg MPEG-4)
==========================================================================
==========================================================================
Forced audio codec: mad
Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
AUDIO: 48000 Hz, 2 ch, s16le, 1509.8 kbit/98.29% (ratio: 188719->192000)
Selected audio codec: [ffdts] afm: ffmpeg (DTS)
==========================================================================
AO: [alsa] 48000Hz 2ch s16le (2 bytes per sample)
Starting playback...
VDec: vo config request - 720 x 416 (preferred colorspace: Planar YV12)
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is 1.73:1 - prescaling to correct movie aspect.
VO: [xv] 720x416 => 720x416 Planar YV12  [fs]
gnome_screensaver_control()00 ct:  0.000 185/185 13%  0% 10.5% 4 0
Exiting... (Quit)




mplayer -ao alsa:device=iec958 -fs vob_dts_digitalexperience.vob

MPEG-PS file format detected.
VIDEO:  MPEG2  720x576  (aspect 3)  25.000 fps  9800.0 kbps (1225.0 kbyte/s)
xscreensaver_disable: Could not find XScreenSaver window.
GNOME screensaver disabled
==========================================================================
Opening video decoder: [mpegpes] MPEG 1/2 Video passthrough
VDec: vo config request - 720 x 576 (preferred colorspace: Mpeg PES)
Could not find matching colorspace - retrying with -vf scale...
Opening video filter: [scale]
The selected video_out device is incompatible with this codec.
Try adding the scale filter, e.g. -vf spp,scale instead of -vf spp.
VDecoder init failed :(
Opening video decoder: [libmpeg2] MPEG 1/2 Video decoder libmpeg2-v0.4.0b
Selected video codec: [mpeg12] vfm: libmpeg2 (MPEG-1 or 2 (libmpeg2))
==========================================================================
==========================================================================
Forced audio codec: mad
Opening audio decoder: [ffmpeg] FFmpeg/libavcodec audio decoders
AUDIO: 48000 Hz, 2 ch, s16le, 1536.0 kbit/100.00% (ratio: 192000->192000)
Selected audio codec: [ffdts] afm: ffmpeg (DTS)
==========================================================================
AO: [alsa] 48000Hz 2ch s16le (2 bytes per sample)
Starting playback...
VDec: vo config request - 720 x 576 (preferred colorspace: Planar YV12)
VDec: using Planar YV12 as output csp (no 0)
Movie-Aspect is 1.78:1 - prescaling to correct movie aspect.
VO: [xv] 720x576 => 1024x576 Planar YV12  [fs]
gnome_screensaver_control()00 ct:  0.040 152/152 16%  2% 12.0% 7 0
Exiting... (Quit)

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






More information about the MPlayer-users mailing list