[Alsa-user] mplayer, dmix and various bitrates

[Ciprian P. <ci...@zu...>]

Hello, I'm new to this so please have patience with me.

I have a FM801 based soundcard (Genius SoundMaker 5.1). I wanted to enable
software mixing so I don't have mplayer and xmms blocking each other and
such stuff. I accomplished it with the ~/.asoundrc at the end of this
message.

The trouble I'm having: various movie clips I watch with mplayer have
various bitrates ie. not all are 44100. Problem is that dmix transforms it
to whatever rate I specify with the "rate" config, but it actually causes
mplayer to go slower or faster, depending on whether the original rate was
more or less than 44100.

For instance, if I have a less than 44100 bitrate on a movie, mplayer plays
it faster than normal and the sound is sqweaky.

It's only mplayer that does this, xmms plays low bitrates at normal speed.

Any idea how I can make mplayer+dmix work well together at any combination
of movie rate/dmix rate?

I tried using -af resample=value with mplayer to try and match the rate
that dmix enforces, but it only works for mplayer 0.95. With Mplayer 1.0
it for certain combinations of the original rate and the target rate (ie.
24k to 48k), but other combinations (44.1k to 48k) will produce horrible
sound.

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

pcm.!default {
    type plug
    slave.pcm "ossmix"
}
pcm.dsp0 {
    type plug
    slave.pcm "ossmix"
}

ctl.mixer0 {
    type hw
    card 0
}

pcm.ossmix {
    type dmix
    ipc_key 1024          # must be unique!
    slave {
        pcm "hw:0,0"      # you cannot use a "plug" device here, darn.
        period_time 0
        period_size 1024  # must be power of 2
        buffer_size 8192  # dito. It
        #format "S32_LE"
        #periods 128      # dito.
        rate 44100        # with rate 8000 you *will* hear,
                          # if ossmix is used :)
    }
    bindings {
        0 0   # from 0 => to 0
        1 1   # from 1 => to 1
    }
}


-- 
Ciprian Popovici