[wdmaudiodev] Re: avstream pin allocator framing requirements

  • From: Tim Roberts <timr@xxxxxxxxx>
  • To: wdmaudiodev@xxxxxxxxxxxxx
  • Date: Tue, 20 Jun 2006 10:07:00 -0700

Nick Dowell wrote:

> I'm in the middle of writing my first avstream-based minidriver, and
> have been experimenting with the behaviour of everything. I'm
> confused, though, when it comes to the concept of allocator framing.
> I gather from the DDK documentation that I should be able to declare a
> KSALLOCATOR_FRAMING_EX struct and point to it in my pin descriptor,
> and through it specify what frame sizes my pin's process dispatch can
> accept.
>    1024,                    // Frames
>    6,                       // MinFrameSize
>    6                        // MaxFrameSize
> );
> Now with these requirements specified by my pin, I'd expect to be
> given up to 1024 frames, each of 6 bytes in size, in one call to my
> process dispatch. What I actually get passed is one frame 8192 bytes
> long, clearly beyond the range I specified.

What sample did you start from?  Several of the samples modify the
framing requirements on the fly using KsEdit when the actual pin format
is established.

Is this a source filter, or is there someone upstream?  If there is a
filter upstream from you, then it may be that your allocator is
involved.  You can be handed the frames they supply.

Tim Roberts, timr@xxxxxxxxx
Providenza & Boekelheide, Inc.


WDMAUDIODEV addresses:
Post message: mailto:wdmaudiodev@xxxxxxxxxxxxx
Subscribe:    mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=subscribe
Unsubscribe:  mailto:wdmaudiodev-request@xxxxxxxxxxxxx?subject=unsubscribe
Moderator:    mailto:wdmaudiodev-moderators@xxxxxxxxxxxxx


Other related posts: