[alsa-devel] Digigram ISA cards

Takashi Iwai tiwai at suse.de
Wed Apr 25 15:16:15 CEST 2007

At Wed, 25 Apr 2007 08:00:12 -0500,
Ash Willis wrote:
> Hi, I'm thinking about trying to write a driver for some old Digigram cards
> soon, namely the PCX11 and PCX9. I might be wrong but it seems these cards
> natively support MPEG layers I and II and only actually support PCM by
> re-encoding in-driver.
> Does alsa-lib support MPEG conversions?

No, and most likely won't be in as of the current form.

> Are there examples of drivers that already do this type of thing?

Depends on what you need to handle.  The biggest challenge would be a
stream with variable bitrates.  Currently, ALSA framework assumes the
constant bitrate streams.  If your mpeg stream is also in a constant
bitrate, you may handle it simply as a special form of PCM, for
example, as AC3 does right now.


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