Re: Implement audio jog/shuttle using IMediaSeeking::SetPositions



On Fri, 22 Sep 2006 11:48:01 -0700, Newbie wrote:

So what actually happens when you perform the seek to the previous frame
and then step forward one to the one you're interested in?
To simulate the backward stepping (though it's not really correct), I want to
step back one frame and then play one frame equivalent of audio in forward
direction. But after the audio play, I still need to show the one frame
ealier.
Say, if I am at pos 20, SetPos will set my pos to 19, now I want to play one
frame equivalent audio at frame 19 and I call IVideoFrame::Step, my guess is
that this call will play both audio and video so after the call, my cursor
position
is at 20 (= video shown should be at pos 20). But I need to show video at 19
since the user stepped backward - I was expecting I should call another SetPos
but even without that, my video is still showing pos 19, so I was wondering
why...

IIRC the frame step interface has a boundary condition problem, in that
Step(1) will sometimes stop where you are and sometimes step 1 forward.
Once you are in step mode, you can reliably step, but that first call seems
unreliable.

I can't help but feel that to achieve anything really useful you are going
to need a filter to capture and re-order sections of the audio. I would be
very surprised if you can get it to work well just using seeking and frame
stepping.

G
.