Re: Getting samples from single filter

On Tue, 31 May 2005 12:09:09 -0600, "Jeremy Noring" <someone@xxxxxxxxxx>
wrote:

>>>> Hi there.
>>>> Just a small question - is calling a method
>>>> IMemInputPin->Receive(pMsample)
>>>> going to deliver a transformed sample (by the filter using that
>>>> meminput)
>>>> to pMsample's buffer or just simplu copy data to that buffer?

>>>It should be noted that applications typically do not call IMemInputPin
>>>interface methods--this is taken directly from the DXSDK.
>>>
>>>That being said, yes--you're going to receive a fully populated
>>>IMediaSample.

>> Actually, what you do is pass a sample to the filter with this method,
>> you don't get a sample from the filter. If it's an in-place transform
>> filter the original sample _may_ be modified when the function returns,
>> but this is not guaranteed. Other filters typically don't do anything
>> with the sample that is passed in through Receive().

>Darn, you're right. =)
>
>I always get that backwards because of the naming, and forget that it's the
>upstream filter calling the downstream filter's Receive() method. I deal so
>little with these underlying guts (really, why bother?) that I probably
>don't know them as well as I should.

I know, the naming is very confusing and feels very backwards. I would
expect the functions to be named from the caller's point of view, and
the caller is delivering the sample, not receiving it.

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