Contrast stretching an image by openCV
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I'm trying to stretch the contrast of an image to the range of 0-255 using cvNormalize. But when I print out the output pixel values, Some negative numbers appear as the pixel value. I appreciate if you help me find out where the origin of the problem is. This is the code:

    cvNormalize(srcImage, dstImage, 0, 255, CV_MINMAX );

    for ( int pixel = 0; pixel < dstImage->height * dstImage->width; pixel++ ) {
        printf("%d\t",*(dstImage->imageData + pixel));
    }