VideoCapture reading AVI changes original video brightness.

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Hello I am facing very strange behavior while reading AVI video from disk using VideoCapture .

The problem is that there is difference in the brightness between the original image and the image was read using VideoCapture,feels like it applying some histogram equalization or other algorithm on my original image.

Original image:

VideoCapture image:

The original image was saved from "VirtualDub" program without any filters.

Read method :

VideoCapture videoCapture;
videoCapture.open(videoFileName);
Mat image;
videoCapture.read(image);

Any ides what can cause this ? sounds like codec (ffmpeg.dll) bug or anything else ?