Gaussian pyramid

[xthepoet]

When I was reviewing the code for the gaussian_video function:

def gaussian_video(video, shrink_multiple):
    """Create a gaussian representation of a video"""
    vid_data = None
    for x in range(0, video.shape[0]):
        frame = video[x]
        gauss_copy = numpy.ndarray(shape=frame.shape, dtype="float")
        gauss_copy[:] = frame
        for i in range(shrink_multiple):
            gauss_copy = cv2.pyrDown(gauss_copy)

        if x == 0:
            vid_data = numpy.zeros((video.shape[0], gauss_copy.shape[0], gauss_copy.shape[1], 3))
        vid_data[x] = gauss_copy
    return vid_data

It seems like it's just downsampling and overwriting gauss_copy 4 times (lines 106-107). I thought the algorithm saved all levels of the pyramid instead of just the lowest one?

[brycedrennan]

This is by design. I was similarly confused given the name "pyramid" but this appears to be what MIT did in their matlab code as well. I haven't looked at the laplacian pyramid yet so maybe that works differently.