PDA

View Full Version : IC image control SDK vs DirectShow



yan_zhao_ep
June 26, 2014, 05:43:52
Hi Stefan,

You said in this thread (http://www.theimagingsourceforums.com/showthread.php?324959-More-control-over-cameras) that the image control SDK encapsulates DirectShow, so the methods like openLive, startLive, snapImage are actually calling DirectShow functions internally?

Also does there exist a set of functions/methods that talks to the camera driver directly?

Stefan Geissler
June 26, 2014, 09:36:41
The driver is a WDM DirectShow driver. Therefore, DirectShow functions are used to communicate.

yan_zhao_ep
June 26, 2014, 14:28:59
Then what about VCDProperties? I thought they are set by bypassing DirectShow, so there must be a secret tunnel ;-)

I am asking because I want to see if the performance of the camera can be further improved.

Thanks,


YZ

Stefan Geissler
June 26, 2014, 14:45:24
They use the KsPropertySet. So you wont win anything.

yan_zhao_ep
June 26, 2014, 15:17:28
Then what about using DirectShow only? Have you by any chance checked the overhead using the SDK vs DirectShow?

Stefan Geissler
June 26, 2014, 15:28:07
You can give it a try. I do not think, that this will be remarkable faster.

yan_zhao_ep
June 26, 2014, 15:31:45
Alright, thanks very much for the help. :-)

yan_zhao_ep
June 26, 2014, 16:56:22
Actually I do have another question, is there a way to set ROI using DirectShow alone?

EDIT: I meant any ROI size. I can only set the resolution to
640x480
1024x768
1280x720
1280x960
1920x1080
2560x1920
2592x1944

Stefan Geissler
June 26, 2014, 17:27:51
Well, this is difficult, since I usually do not use DirectShow on my own.

But have a look on the AM_MEDIA_TYPE, and queried data of the pins. Look for the granularity. It is the same information, the VideoFormatDesc object returns.