Palettes and kernel-streaming driver (USBCAMD2)

Hello,

I am writing a USB camera mini-driver using
USBCAMD2. I have the basic driver working, but need to
get the video into the desired format for proper viewing
in DirectShow. The video is 8-bit grayscale, and is
interlaced (I receive two fields in one "frame" from the
camera and interlace them in the CamProcessRawVideoFrameEx
() function in my minidriver. They are displayed on the
screen using RGB8 (8-bit color.)


I would like to know how I can describe (or set
somehow) the color palette as a grayscale palette. I've
tried converting to RGB24 in the minidriver and
replicating the 8-bit pixel value that I receive from the
camera in the RGB fields. This works, but is so slow
that I'm dropping frames. Any suggestions or hints would
be appreciated.

Sincerely,


Howard M. Harte

========================
Harte Technologies, LLC.
(925) 551-0120 (voice)
(925) 551-0125 (fax)
http://www.hartetechnologies.com/

Maxim
Tue Oct 21 07:35:59 CDT 2003

> I would like to know how I can describe (or set
> somehow) the color palette as a grayscale palette. I've

Are you sure you will need this? Why not use the 8bpp grayscale everywhere in
the DirectShow pipeline, and offload the conversion burden to the Video
Renderer?

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

Tom
Tue Oct 21 15:52:14 CDT 2003

Max, Howard, sorry to jump in.

Max,

> Are you sure you will need this? Why not use the 8bpp grayscale everywhere
in
> the DirectShow pipeline, and offload the conversion burden to the Video
> Renderer?

I have been wondering about this myself, are there predefined media types
for 8bpp grayscale or do you need to implement a custom type. What about 10
or 12 bpp?

Regards,

Tom Udale