Pushing up data through the stream in quartz

[Maarten Lankhorst]

I'm trying to figure out how to do this, but I can't find anything on 
the subject.
 From what I can tell, you have to make a media sample, then use 
outputpin_sendsample to deliver it,
so, how do I fill up a media sample with a single frame?
For now, just with NULL data would be sufficient..

[Robert Shearman]

Maarten Lankhorst wrote:
> I'm trying to figure out how to do this, but I can't find anything on 
> the subject.
> From what I can tell, you have to make a media sample, then use 
> outputpin_sendsample to deliver it,
> so, how do I fill up a media sample with a single frame?

A sample *is* a single frame, so there is no special case. For code that 
does this, please see dlls/quartz/acmwrapper.c.
The general pattern is:
1. Get a blank available sample (OutputPin_GetDeliveryBuffer).
2. Set the size of the data represented by the sample 
(IMediaSample_SetActualDataLength)
3. Get a pointer to the sample buffer (IMediaSample_GetPointer)
4. Fill with data (memcpy).
5. Send the sample to the downstream filter (OutputPin_SendSample).
> For now, just with NULL data would be sufficient..

Replace the above mentioned memcpy call with a memset instead then.

Rob