def colorize_channels(image_tensor):
    """
    Colorizes each channel of an image tensor.

    Outputs numpy array that can be easily displayed using opencv.

    Parameters
    ----------
    image_tensor : numpy.ndarray, required
        (height, width, channels)

    Raises
    ------
    AssertionError
        Raised if image tensor contains wrong number of dimensions.
    """
    assert(len(image_tensor.shape) == 3)

    # initialize image
    image_shape = list(image_tensor[:,:,0].shape)
    image_shape.append(3)
    image = np.zeros(image_shape)

    for channel_num in range(len(image_tensor[0,0])):
        random_color = list(np.random.choice(range(256), size=3))
        channel = image_tensor[:,:,channel_num]

        # iterate through channel values
        for idx in np.argwhere(channel > 0.5):
            image[idx[0], idx[1]] = random_color

    return image