Converts the file in file_path to a numpy array (matrix) representing an RGB image
    The dimensions of the image are calculated using __determine_dimensions.
    Padding is added provide enough bytes to generate the image (between 1 and 3 bytes can be added).

def _to_image_array(file_path):
    """
    Converts the file in file_path to a numpy array (matrix) representing an RGB image
    The dimensions of the image are calculated using __determine_dimensions.
    Padding is added provide enough bytes to generate the image (between 1 and 3 bytes can be added).
    """
    _log.debug("File '%s' to image", file_path)
    data = numpy.fromfile(file_path, numpy.uint8)
    orig_len = len(data)
    pad_req = (3 - (orig_len % 3))
    pad_req += 3 if pad_req == 0 else 0
    final_len = orig_len + pad_req
    num_of_pixels = final_len // 3
    w, h = _determine_dimensions(num_of_pixels)
    reshaped = numpy.zeros((w, h, 3), dtype=numpy.uint8)
    for i in xrange(final_len):
        sidx = i // 3
        y = sidx % h
        x = sidx // h
        s = i % 3
        reshaped[x, y, s] = data[i] if i < orig_len else 0
    reshaped[-1, -1, 2] = pad_req

    return reshaped