ECE595 Computer Vision Notes

Video Acquistion

download vid.zip

vid1.m USB camera example
vid2.m object size vs. distance from camera
vid3.m reading .avi video capture file
pat1.m edge location
video preview video preview and custom callback routines

Download: seqs.zip

vid4.m captures sequences of snapshots at equally spaced times, with a audible beep before each snapshot.
vid4a.m reviews the sequences. Those presented here (taken 26 Jan 2011) show image translation (different magnitudes), image rotation (axis toward camera), and image rotation with the axis vertical.

Image Basics

Download basics_MATLAB.zip

aoi area or regions of interest
bp1.m difference images (bipolar).
bp1v.m difference images from class image sequence seq1 (26 Jan 2011)
components.m color components of an image

2D geometric transformations

tran1.m translate image (zero fill).
rot1.m image rotation.
rot2.m image rotation (video sequence).
distort.m image distortion
general 2-D transformations (MATLAB tform)

Correlation

auto.m auto-correlation

3D Computer Graphics

vis1 simple 3D object (source)
surface MATLAB surface objects
groups MATLAB group objects and homogenous transformations in 3D scenes (source)
rotations demonstrate rotation operations (source)

Harris-Stephens corner algorithm

A camera mounted on tripod was used to capture images of a fixed checkboard target from different positions.
The camera was translated and rotated (yaw) as if it were mounted on a mobile robot.

Cube studies

Hall4 Studies

Download hall4.zip

hallway1.m
hallway2.m
hallway3.m
hallway4.m
hallway5.m
- back_projection.m
- draw5.m
- rotation_matrix.m
- fval2.m (based on vanishing points)
- fval3.m (based on back-propagated points)
test1.m
- fval4.m
hallway6.m

Camera Calibration

Optical Flow

flow1		Moving a camera over a plane populated by equally spaced dots.
flow2		Same thing, but randomly placed dots

Stereo

Download MATLAB source from stereo.zip

fig1  stereo camera geometry
fig2  back projection (triangulation)
fig3  same, but with multiple points

Panorama

photos.m Use TFORM to overlay two images.

Maintained by John Loomis, last updated 15 April 2011