OpenCV is able to change to composite input?

I would like to know if OpenCV is able to set the camera (dev/video1) to composite or S-video input.

The camera I was using only runs in composite input, but v4l2 opens dev/video1 in S-Video input by default. V4l2 is able to change from S-video to composite input by QT V4l2 utils application.

The opencv is using v4l to capture imagens from camera, and I want to change to composite input in code using OpenCV. Is that possible? If it's not, what is the solution to this?

Thanks in advance.

Solution

You have just to change the input with "v4l2-ctl" ! For example, I use Python on my raspberry to capture the video stream from S-Video with OpenCV :

    import cv, os

    print "Initializing video capture from /dev/video0 ..."
    capture = cv.CaptureFromCAM(0)
    cv.SetCaptureProperty(capture,cv.CV_CAP_PROP_FRAME_WIDTH, 720)
    cv.SetCaptureProperty(capture,cv.CV_CAP_PROP_FRAME_HEIGHT, 576)

    print "Configuring video capture (V4L2) ..."
    os.system("v4l2-ctl -d /dev/video0 -i 5 -s 4 --set-fmt-video=width=720,height=576,pixelformat=4")

With :

-d : device (in my case /dev/video0),
-i : input. for my Easycap (0 = CVBS0; 1 = CVBS1; 2 = CVBS2; 3 = CVBS3; 4 = CVBS4; 5 = S-VIDEO)
-s : norm (0 = PAL_BGHIN; 1 = NTSC_N_443; 2 = PAL_Nc; 3 = NTSC_N; 4 = SECAM; 5 = NTSC_M; 6 = NTSC_M_JP; 7 = PAL_60; 8 = NTSC_443; 9 = PAL_M;)