05694487 is referenced by 58 patents and cites 3 patents.

A method for determining feature points comprises a step for (a) providing directional gradients and a gradient magnitude for each pixel in the video frame, (b) normalizing the directional gradients by dividing the directional gradients with the gradient magnitude, (c) generating a first edge map having the gradient magnitude for each pixel, (d) generating a second edge map having the normalized direction gradients for each pixel, (e) dividing the first edge map into a plurality of blocks of an identical size, (f) providing, for each of the pixels included in each of the blocks, normalized directional gradients for a set of a predetermined number of pixels from the second edge map, (g) obtaining a variance for each of the pixels included in each of the blocks based on the provided normalized directional gradients, (h) determining a feature point for each of the blocks based on the gradient magnitude and variance corresponding to each of the pixels therein.

Title
Method and apparatus for determining feature points
Application Number
8/434824
Publication Number
5694487
Application Date
May 4, 1995
Publication Date
December 2, 1997
Inventor
Min Sub Lee
Seoul
KR
Agent
Anderson Kill & Olick P C
Assignee
Daewoo Electronics
KR
IPC
G06K 9/46
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