[MPlayer-users] dts audio CD playback (-ac dtscd) with a52 CRC errors

[Lars Steinke]

Hi there,

when trying to get mplayer to play back a dts audio CD via spdif
passthrough,  I fail miserably with "mplayer -ac dtscd cdda://1" or
"mplayer -ao alsa:device=spdif -ac dtscd cdda://1":

MPlayer dev-CVS--4.0.2 (C) 2000-2005 MPlayer Team
CPU: Advanced Micro Devices Athlon 4 /Athlon MP/XP Palomino (Family: 6,
Stepping: 2)
Detected cache-line size is 64 bytes
MMX2 supported but disabled
3DNow supported but disabled
3DNowExt supported but disabled
CPUflags:  MMX: 1 MMX2: 0 3DNow: 0 3DNow2: 0 SSE: 1 SSE2: 0
Compiled for x86 CPU with extensions: MMX SSE
87 audio & 200 video codecs
Failed to open /dev/rtc: Device or resource busy (it should be readable
by the user.)
Opening joystick device /dev/input/js0
Can't open joystick device /dev/input/js0 : No such file or directory
Can't init input joystick
Setting up LIRC support...
mplayer: could not connect to socket
mplayer: No such file or directory
Failed to open LIRC support.
You will not be able to use your remote control.
Playing cdda://1.
Found Audio CD with 11 tracks
Cache fill:  0.00% (0 bytes)
Track 1
==========================================================================
Forced audio codec: dtscd
Opening audio decoder: [hwac3] AC3/DTS pass-through S/PDIF
No accelerated IMDCT transform found
hwac3: switched to AC3, 56000 bps, 48000 Hz
a52: CRC check failed!
AUDIO: 48000 Hz, 2 ch, ac3, 56.0 kbit/3.65% (ratio: 7000->192000)
Selected audio codec: [dtscd] afm:hwac3 (DTS CDDA through S/PDIF)
==========================================================================
Building audio filter chain for 48000Hz/2ch/ac3 -> 0Hz/0ch/??...
alsa-init: 1 soundcard found, using: iec958:{CARD 0 AES0 0x02 AES1 0x82
AES2 0x00 AES3 0x02}
alsa: 48000 Hz/2 channels/4 bpf/32768 bytes buffer/Signed 16 bit Little
Endian
AO: [alsa] 48000Hz 2ch ac3 (1 bps)
Building audio filter chain for 48000Hz/2ch/ac3 -> 48000Hz/2ch/ac3...
Video: no video
Starting playback...
a52: CRC check failed!
a52: CRC check failed!
a52: CRC check failed!
a52: CRC check failed!
a52: CRC check failed!
a52: CRC check failed!  %
alsa-play: xrun of at least 158.043 msecs. resetting stream
a52: CRC check failed!  %
a52: CRC check failed!
a52: CRC check failed!
a52: CRC check failed!
a52: CRC check failed!
alsa-play: xrun of at least 2066.745 msecs. resetting stream
...

Using mplayer -rawaudio on:format=0x2001 cdda://1 behaves identically...
It seems mplayer fails to switch to DTS here (and thus expects AC3 data).

This is for several different audio CDs that play back without problem on
a standalone DVD player (with dts passthrough to my amp with dts
decoder). When using dtsdec on a file generated with -dumpaudio from
that CD, it decodes the dts just fine as well... 

At the same time, a dts track from the LOTR DVD plays without glitch on
that hardware (Cirrus Logic CS4294 soundcard optical out):
mplayer -ao alsa:device=spdif -ac hwdts dvd://1

...
DVD successfully opened.
MPEG-PS file format detected.
VIDEO:  MPEG2  720x576  (aspect 3)  25.000 fps  7500.0 kbps (937.5
kbyte/s)
==========================================================================
Forced audio codec: hwdts
Opening audio decoder: [hwac3] AC3/DTS pass-through S/PDIF
No accelerated IMDCT transform found
hwac3: switched to DTS, 768000 bps, 48000 Hz
AUDIO: 48000 Hz, 2 ch, ac3, 768.0 kbit/50.00% (ratio: 96000->192000)
Selected audio codec: [hwdts] afm:hwac3 (DTS through S/PDIF)
==========================================================================
==========================================================================
Opening video decoder: [mpegpes] MPEG 1/2 Video passthrough
VDec: vo config request - 720 x 576 (preferred csp: 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.
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))
==========================================================================
Building audio filter chain for 48000Hz/2ch/ac3 -> 0Hz/0ch/??...
alsa-init: 1 soundcard found, using: spdif
...

So for -ac hwdts the switch to DTS works, but not for -ac dtscd!
Any idea what else I could try?

Thanks,
-- 
       /(__  __|\          Lars Steinke, Stuttgart, Germany
      (    \/  __)_        Physicist, ICID, MBA, Consultant
       )   (_____  /       For information see www.lsweb.de
      /___________/        Debian GNU/Linux: www.debian.org