Re: directShow samples don't build and/or regsvr32

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On 20 Mar 2007 01:17:47 -0700, Howard wrote:

I've built the asyncflt sample which I was advised would be the
starting point for developing my own source filter that reads from a
socket instead of a file. Before I start building all the network
goo, I wanted to see if I could get asyncflt to work with WMV files
(It appears to only work for AVI files).
I don't see why this advice was given. The only reason to build a variant
of asyncfilt is if your source may have many different sorts of content and
you cannot even guess what demuxing or parsing maybe required. If you KNOW
the sort of content (e.g. mp4) which will be contained then a plain push
source is a great deal easier.

Of course if you are making a general purpose transport that is a different
matter.

My first step was to see if I could get my filter to connect to WMV
Video Decode DMO, using graphedt as my test driver.
I modified the IPin implementation to support MEDIATYPE_Video, and
subtype WMVP, which are types the receive pin I'm trying to connect to
supports.

I'm getting error code 8004022A (VFW_E_TYPE_NOT_ACCEPTED) from the
receive pin's ReceiveConnection method.This seems odd, since the pin
advertises accepting MEDIATYPE_Video, and subtype WMVP..

I stepped into wmvdmod.dll to try and see where the error is coming
from, and it looks like the receive pin is also expecting a format
type of FORMAT_VideoInfo, and a VIDEOINFOHEADER, which I also send,
but don't initialize (since I have no idea what's expected there)
That's what you need to do. This would normally be carried as metadata in
the stream (in some way). for now you can hard code the properties. If
you know what's in the stream it should be reasonably easy to do this.

b.t.w. it would have been a good idea to start this as a new thread - the
original one will have dissapeared from many nntp servers by now and the
context lost. And it is on a different subject!

Iain
.

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