Do you recommend to use DMA in MPEG2 TS Video Streaming?

Hi all,

I am trying to stream MPEG2 TS data through USB to the PC for Directshow
playback, i am developing a USB Avstream driver,

understanding that DMA faster, uses less CPU time, but is quite hard to
control and debug, my question is, do the experienced ones recommend to use
DMA at all in this kind of application? or it dose not matter at all ?

Thanks.
--
--------------------------------------------
William

Gennady
Tue Dec 11 01:49:10 PST 2007

> I am trying to stream MPEG2 TS data through USB to the PC for Directshow
> playback, i am developing a USB Avstream driver,
>
> understanding that DMA faster, uses less CPU time, but is quite hard to
> control and debug, my question is, do the experienced ones recommend to use
> DMA at all in this kind of application? or it dose not matter at all ?

In all our MPEG-2 applications, we always use DMA to transfer data to/
from device in production versions. Although it usually takes some
time to make DMA work properly, it still makes sense to use it because
of performance.

Regards,
Gennady Mayko.

Maxim
Tue Dec 11 10:59:17 PST 2007

With USB devices, DMA is not your job. The host controller driver will do
the DMA.

--
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
maxim@storagecraft.com
http://www.storagecraft.com

"William Xie" <WilliamXie@discussions.microsoft.com> wrote in message
news:4A6FD30B-9B75-4836-948F-097B5BED6B98@microsoft.com...
> Hi all,
>
> I am trying to stream MPEG2 TS data through USB to the PC for Directshow
> playback, i am developing a USB Avstream driver,
>
> understanding that DMA faster, uses less CPU time, but is quite hard to
> control and debug, my question is, do the experienced ones recommend to use
> DMA at all in this kind of application? or it dose not matter at all ?
>
> Thanks.
> --
> --------------------------------------------
> William

WilliamXie
Tue Dec 11 18:36:03 PST 2007

Hi Max and Mayko,

Thanks.
I will evaluate this more, your advice helps a lot.

:-)

--------------------------------------------
William


"Maxim S. Shatskih" wrote:

> With USB devices, DMA is not your job. The host controller driver will do
> the DMA.
>
> --
> Maxim Shatskih, Windows DDK MVP
> StorageCraft Corporation
> maxim@storagecraft.com
> http://www.storagecraft.com
>
> "William Xie" <WilliamXie@discussions.microsoft.com> wrote in message
> news:4A6FD30B-9B75-4836-948F-097B5BED6B98@microsoft.com...
> > Hi all,
> >
> > I am trying to stream MPEG2 TS data through USB to the PC for Directshow
> > playback, i am developing a USB Avstream driver,
> >
> > understanding that DMA faster, uses less CPU time, but is quite hard to
> > control and debug, my question is, do the experienced ones recommend to use
> > DMA at all in this kind of application? or it dose not matter at all ?
> >
> > Thanks.
> > --
> > --------------------------------------------
> > William
>
>