Week 1 ReportRuben Villegas

Lucas-Kanade Optical Flow

• Problems I had– Getting used to Matlab– Ax = fx(i-1:i+1,j-1:j+1)• If matrix Ax = [1 2 3; 4 5 6; 7 8 9], Ax(:) == [1 4 7 2 5 8 3 6 9].• Solution Ax = fx(i-1:i+1;j-1:j+1)’, where Ax = [1 4 7, 2 5 8, 3 6 9], and A(:) == [1 2 3 4 5 6 7 8 9]

– pinv vs inv for U (A’A )-1A’ft

Functions Implemented

• opticalFlow– Takes 2 images and outputs an optical flow image.

• opticalFlow2– Failed attempt to implement pyramids.– Ft calculation problems.

• opticalFlow3– Takes a sequence and outputs a video of the

optical flow of that video

LK Optical Flow

LK Optical Flow with Pyramids?

SIFT Descriptor

• Problems I had– Figure out how to use 3-Dimensional Matrixes• Split 16x16 matrixes into 4x4

– uint8 underflow?• m(y-1,x-1) = sqrt(double((im(y+1,x)-im(y-1,x))^2+(im(y,x+1)-im(y,x-1))^2))• Solution, conver im to double beforehand.