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Task/Bitmap-Histogram/00DESCRIPTION

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+Extend the basic bitmap storage defined [[Basic_bitmap_storage|on this page]] to support dealing with image histograms. The image histogram contains for each luminance the count of image pixels having this luminance. Choosing a histogram representation take care about the data type used for the counts. It must have range of at least 0..NxM, where N is the image width and M is the image height.
+
+'''Test task'''
+
+Histogram is useful for many image processing operations. As an example, use it to convert an image into black and white art. The method works as follows:
+* Convert image to grayscale;
+* Compute the histogram
+* Find the median: defined as the luminance such that the image has an approximately equal number of pixels with lesser and greater luminance.
+* Replace each pixel of luminance lesser than the median to black, and others to white.
+Use [[read ppm file | read]]/[[write ppm file]], and [[grayscale image]] solutions.