Pixel Data
an array of bytes that defines the bitmap bits. These are the actual image data, represented by consecutive rows, or "scan lines," of the bitmap. Each scan line consists of consecutive bytes representing the pixels in the scan line, in left-to-right order. The system maps pixels beginning with the bottom scan line of the rectangular region and ending with the top scan line.
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RGB values are stored backwards i.e. BGR.
(I interpret this as meaning that you have the B, G, R for the left-bottom pixel, then the B, G, R for the one to the right of that, and so on, then the B, G, R for the second-from the bottom left pixel, and so on. Eventually the end of the file would be B, G, R for the top right corner.)
