Configuring camera properties in new OCV 2.4.3

Question

I may just be googling wrong, but I cannot find out a way (read function) to change properties of camera in the new Open CV. I need to disable auto exposure

Answer 1

You can use the OpenCV API to do this using VideoCapture::Set(). Here is an example of how to set the exposure manually in Python:

import cv2

cap = cv2.VideoCapture(0)
cap.set(cv2.CAP_PROP_EXPOSURE,-4)

while(True):
    ret, frame = cap.read()

    cv2.imshow('frame',frame)
    if cv2.waitKey(1) & 0xFF == ord('q'):
        break

cap.release()
cv2.destroyAllWindows()

Here are the notes I have about the exposure time for each frame. Though I believe they are camera specific, they give you a good idea.

-1  640 ms
-2  320 ms
-3  160 ms
-4  80 ms
-5  40 ms
-6  20 ms
-7  10 ms
-8  5 ms
-9  2.5 ms
-10 1.25 ms
-11 650 µs
-12 312 µs
-13 150 µs

The same function has settings for GAIN and many other values, though I have not tried them.

A bit more discussion at Setting Manual Exposure in OpenCV