[mythtv-users] AC3 and mythtv

tom.kiernan3 at verizon.net tom.kiernan3 at verizon.net
Fri Dec 31 21:27:50 UTC 2004


Here's my GOAL:

mythtv and HD3000 ATSC with "AC3 to SPDIF" selected, via digital coax to Denon AVR-1705 receiver, then output beautiful DTS 6.1 to Klipsch speakers!

The receiver indicates a Digital signal and I hear analog music, but no mythtv sound when "AC3 to SPDIF" selected.

Just found a thread that says Audigy driver only supports 48kHz 16 bit output, and my receiver expects DTS 96kHz 24 bit.

Is there any ALSA supported soundcard/driver that supports 96kHz 24 bit output stream?  Any 96/24 support plans for the Audigy driver?

Thanks!

INFO that might help:

mythfrontend Setup = ALSA:spdif

[tom at localhost tom]$ uname -r
2.6.9

[tom at localhost tom]$ rpm -qa |grep alsa
alsa-driver-1.0.7-33.rhfc2.at
kernel-module-alsa-2.6.7-1.437.1.ll.rhfc2.ccrmasmp-1.0.5a-1.cvs.rhfc2.ccrma
kernel-module-alsa-2.6.8-1.521-1.0.7-33.rhfc2.at
gnome-alsamixer-0.9.6-3.1.fc2.fr
alsa-lib-devel-1.0.3a-2
alsa-utils-1.0.7-11.rhfc2.at
balsa-2.0.17-1
alsa-lib-1.0.3a-2

[tom at localhost tom]$ cat /etc/modprobe.conf
~snip~
alias snd-card-0 snd-emu10k1 
install snd-emu10k1/sbin/modprobe --ignore-install snd-emu10k1 && /usr/sbin/alsactl restore >/dev/null 2>&1 || :
remove snd-emu10k1 { /usr/sbin/alsactl store >/dev/null 2>&1 || : ; }; /sbin/modprobe -r --ignore-remove snd-emu10k1

[tom at localhost tom]$ lspci
~snip~
00:06.0 Multimedia audio controller: nVidia Corporation nForce2 AC97 Audio Controler (MCP) (rev a1)
00:08.0 PCI bridge: nVidia Corporation nForce2 External PCI Bridge (rev a3)
00:09.0 IDE interface: nVidia Corporation nForce2 IDE (rev a2)
00:1e.0 PCI bridge: nVidia Corporation nForce2 AGP (rev c1)
01:04.0 Multimedia audio controller: Creative Labs SB Audigy (rev 03)
01:04.1 Input device controller: Creative Labs SB Audigy MIDI/Game port (re v 03)
01:04.2 FireWire (IEEE 1394): Creative Labs SB Audigy FireWire Port
01:06.0 Multimedia video controller: Conexant Winfast TV2000 XP (rev 05)
01:06.2 Multimedia controller: Conexant: Unknown device 8802 (rev 05)
01:08.0 VGA compatible controller: nVidia Corporation NV11 [GeForce2 MX/MX 400] (rev b2)
02:00.0 VGA compatible controller: nVidia Corporation NV18 [GeForce4 MX 400 0 AGP 8x] (rev c1)

[tom at localhost tom]$ lsmod
Module                  Size  Used by
snd_pcm_oss            46248  0
snd_mixer_oss          16640  4 snd_pcm_oss
snd_emu10k1           100360  5
snd_rawmidi            23844  1 snd_emu10k1
snd_pcm                96136  2 snd_pcm_oss,snd_emu10k1
snd_timer              28932  1 snd_pcm
snd_ac97_codec         66256  1 snd_emu10k1
snd_page_alloc          7688  2 snd_emu10k1,snd_pcm
snd_util_mem            3840  1 snd_emu10k1
snd_hwdep               7428  1 snd_emu10k1
snd                    46564  12 snd_pcm_oss,snd_mixer_oss,snd_emu10k1,snd_rawmidi,snd_pcm,snd_timer,snd_ac97_codec,snd_hwdep
soundcore               8544  4 snd
autofs4                23556  0
sunrpc                159076  1
forcedeth              18432  0
ipt_REJECT              5888  1
ipt_state               1792  1
ip_conntrack           36884  1 ipt_state
iptable_filter          2560  1
ip_tables              15104  3 ipt_REJECT,ipt_state,iptable_filter
floppy                 58928  0
sg                     31520  0
scsi_mod              114252  1 sg
joydev                  8256  0
dm_mod                 50964  0
ohci_hcd               21764  0
ehci_hcd               32004  0
button                  5136  0
battery                 7556  0
ac                      3588  0
tuner                  18212  0
cx8800                 78108  0
cx88xx                 19332  1 cx8800
video_buf              18052  2 cx8800,cx88xx
i2c_algo_bit            8200  1 cx8800
v4l1_compat            12164  1 cx8800
i2c_core               19200  4 tuner,cx8800,cx88xx,i2c_algo_bit
v4l2_common             5120  1 cx8800
btcx_risc               4104  2 cx8800,cx88xx
videodev                7680  1 cx8800
nvidia               3466524  20
ipv6                  237760  14
ext3                  104296  2
jbd                    79000  1 ext3

[tom at localhost tom]$ sudo aplay -L
~snip~
cards 'cards.pcm'
front 'cards.pcm.front'
rear 'cards.pcm.rear'
center_lfe 'cards.pcm.center_lfe'
side 'cards.pcm.side'
surround40 'cards.pcm.surround40'
surround41 'cards.pcm.surround41'
surround50 'cards.pcm.surround50'
surround51 'cards.pcm.surround51'
surround71 'cards.pcm.surround71'
iec958 'cards.pcm.iec958'
spdif 'cards.pcm.iec958'
modem 'cards.pcm.modem'
default {
        type plug
        slave.pcm digital-hw
}
analog {
        type plug
        slave.pcm analog-hw
}
mixed-analog {
        type plug
        slave.pcm dmix-analog
}
digital {
        type plug
        slave.pcm digital-hw
}
mixed-digital {
        type plug
        slave.pcm dmix-digital
}
analog-hw {
        type hw
        card 0
}
digital-hw {
        type hw
        card 0
        device 0
}
dmix-analog {
        type dmix
        ipc_key 1234
        slave {
                pcm analog-hw
                period_time 0
                period_size 1024
                buffer_size 4096
                rate 48000
        }
}
dmix-digital {
        type dmix
        ipc_key 1235
        slave {
                pcm digital-hw
                period_time 0
                period_size 1024
                buffer_size 4096
                rate 48000
        }
}

[tom at localhost tom]$ cat .asoundrc
# Override the default output used by ALSA.
# If you do not override the default, your default
# device is identical to the (unmixed) analog device
# shown below.  If you prefer mixed and/or digital
# output, uncomment the appropriate four lines below
# (only one slave.pcm line).
### Currently set w/digital-hw as the default output,
### comment out this entire section to use unmixed
### analog as your default
### -jarod
pcm.!default {
  type plug
## Uncomment the following to use mixed analog by default
#  slave.pcm "dmix-analog"
## Uncomment the following to use unmixed digital by default
  slave.pcm "digital-hw"
## Uncomment the following to use mixed digital by default
#  slave.pcm "dmix-digital"
}
 
# Alias for analog output on the Audigy (hw:0,0)
# - This is identical to the device named "default"--which
# always exists and refers to hw:0,0 (unless overridden)
# - Therefore, we can specify "hw:0,0", "default", or "analog"
# to access analog output on the Audigy
pcm.analog {
 type plug
 slave.pcm "analog-hw"
}
# Control device (mixer, etc.) for the Audigy card
ctl.analog {
 type hw
 card 0
}
 
# Alias for (rate-converted) mixed analog output on the
# Audigy (hw:0,0)
#  - This will accept audio input--regardless of rate--and
# convert to the rate required for the dmix plugin
# (in this case 48000Hz)
pcm.mixed-analog {
 type plug
 slave.pcm "dmix-analog"
}
# Control device (mixer, etc.) for the Audigy card
ctl.mixed-analog {
 type hw
 card 0
}
 
# Alias for (rate-converted) digital (S/PDIF) output on the
# Audigy (hw:0,0)
#  - This will accept audio input--regardless of rate--and
# convert to the rate required for the S/PDIF hardware
# (in this case 48000Hz)
pcm.digital {
 type plug
 slave.pcm "digital-hw"
}
# Control device (mixer, etc.) for the Audigy card
ctl.digital {
 type hw
 card 0
}
 
# Alias for mixed (rate-converted) digital (S/PDIF) output on the
# Audigy (hw:0,0)
#  - This will accept audio input--regardless of rate--and
# convert to the rate required for the S/PDIF hardware
# (in this case 48000Hz)
pcm.mixed-digital {
 type plug
 slave.pcm "dmix-digital"
}

# Control device (mixer, etc.) for the Audigy card
ctl.mixed-digital {
 type hw
 card 0
}
 
# The following devices are not useful by themselves.  They
# require specific rates, channels, and formats.  Therefore,
# you probably do not want to use them directly.  Instead use
# of of the devices defined above.
 
# Alias for analog output on the Audigy (hw:0,0)
# Do not use this directly--it requires specific rate,
# channels, and format
pcm.analog-hw {
 type hw
 card 0
# The default value for device is 0, so no need to specify
}
# Control device (mixer, etc.) for the Audigy card
ctl.analog-hw {
 type hw
 card 0
}
 
# Alias for digital (S/PDIF) output on the Audigy (hw:0,0)
# Do not use this directly--it requires specific rate,
# channels, and format
pcm.digital-hw {
 type hw
 card 0
 device 0
}
# Control device (mixer, etc.) for the Audigy card
ctl.digital-hw {
 type hw
 card 0
}
 
# Direct software mixing plugin for analog output on
# the Audigy (hw:0,0)
# Do not use this directly--it requires specific rate,
# channels, and format
pcm.dmix-analog {
 type dmix
 ipc_key 1234
 slave {
   pcm "analog-hw"
   period_time 0
   period_size 1024
   buffer_size 4096
   rate 48000
 }
}
# Control device (mixer, etc.) for the Audigy card
ctl.dmix-analog {
 type hw
 card 0
}
 
# Direct software mixing plugin for digital (S/PDIF) output
# on the Audigy (hw:0,0)
# Do not use this directly--it requires specific rate,
# channels, and format
pcm.dmix-digital {
 type dmix
 ipc_key 1235
 slave {
   pcm "digital-hw"
   period_time 0
   period_size 1024
   buffer_size 4096
   rate 48000
 }
}
# Control device (mixer, etc.) for the Audigy card
ctl.dmix-digital {
 type hw
 card 0
}

Tom.




More information about the mythtv-users mailing list