Zoneminder and multichannel cards

Achilleas Mantzios achill at
Thu Oct 11 02:29:04 PDT 2007

Just a question, in context with our previous discussions.
I managed to capture video from more than 1 camera, in zoneminder.
I'd like to ask, whats the theoritical max fps for each of 4 cameras using the 
bktr driver in its FreeBSD-6.2 state?

In my code, with METEOR_CAP_CONTINOUS (single camera) it can do
(as ZM reports) 25 fps (which AFAIK is good), whereas with all 4 cameras
and by using METEOR_CAP_SINGLE, the fps drop down to 2.5 fps/camera.

Is that the max the driver can do, or is my code in trouble?
Where is what i do (pseudocode):

void initialize() {
	if (single camera) {
	        ioctl(m_videohandle, METEORCAPTUR, &c);

void PreCapture(int channel) {
	if (number_of_cameras > 1) { 
/* this runs only when number of cameras are 2 or more */
		/*stop continous capture */
		int tmpc = METEOR_CAP_STOP_CONT;
/*1*/		ioctl(m_videohandle, METEORCAPTUR, &tmpc); 

		/* set the input */
		int tmpint=bktr_dev[channel];
/*2*/		ioctl(m_videohandle, METEORSINPUT, &tmpint);

		/* 3 set single capture mode */
/*3*/		ioctl(m_videohandle, METEORCAPTUR, &tmpc); 

The PreCapture method is never called when number_of_cameras > 1.
In case (number_of_cameras > 1), the operations "1" and "3" are needed to be 
run only the first time that capture() is run. Subsequent runs dont need 

Has the above code any flaws?
If i try to remove syscalls "1","3" from runs 2,3,4,... whould i have better 

Any ideas are wellcome.
Achilleas Mantzios

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