How to fast change image brightness with python + OpenCV?

Question

I have a sequence of images. I need to average brightness of these images.

First example (very slow):

img = cv2.imread(\'test.jpg\')         


        

Answer 1

Might be too old but I use cv.covertTo which works for me

Mat resultBrightImage;    
origImage.convertTo(resultBrightImage, -1, 1, percent); // Where percent = (int)(percent_val/100)*255, e.g., percent = 50 to increase brightness by 50%

convertTo uses saturate_cast at the end to avoid any overflows. I don't use Python and the above is in C++ but I hope it is easily convertible in Python and hope it helps