Re: NUBIE API design.

----- Original Message ----- 
From: "Steve Lhomme"
Sent: Friday, January 02, 2004 6:41 AM
Subject: Re: [Media-api] NUBIE API design.


Paul wrote:
> > 'nuff said.  The API passes messages to the master, and then it
determines
> > what to do.  DirectShow is the greatest blackbox of media.  Half the
time
> > you don't really know what its doing or why.
>
> Just because it's closed source. It's not a design problem.

Well, yes and no.  DirectShow was designed to be its own autonomous system.
To get the same level of control that you get with vfw, you would have to
write an application that is a complete replacement of the DirectShow core,
calling and handling all of the filters directly.  But, doing this would be
near impossible as MS documentation sucks so bad that I can tell.

> > I think that most of the comments that I've seen so far have been about
> > passing the video frames.  IE, if you have to pass the same video frame
5
> > times, that is a lot of memory bandwidth.  If you are working with
> > 1920x1080x32bpp @24p, then you have almost 1.6 Gigabytes per second just
on
> > video frames.  Any copying of the video buffer that you have to do at
this
> > point is going to stretch the limits of many computers.
>
> Hopefully a frame is a shared pointer, not the whole data :)

Sorry, that was my point.  I was just wondering on how he intended to pass
the data around.  If a filter further down the chain changed data in the
frame of a shared pointer, would it screw things if there was an error
somewhere in the chain causing it to need to retransmit data?


Pamel