COMPUTER VISION Larry Wolff MTW Office: 212NEB Office Hours: Wed. 1-2PM

September 8, REQUIREMENTS This is an introductory course on Computer Vision. No previous knowledge of computer vision or image analysis is required. Prerequisite is only that you be computer literate: -Know how to program in C. -Have had some exposure to UNIX type environments. -Able to use a Web Browser.

September 8, GRADING Midterm 20% Final 30% Problem Sets and Lab Projects 50%

September 8, RESOURCES You will need an account on a workstation such as a SUN, DEC, or an SGI. Of course direct access to the JHU network is highly desireable. PCs running Linux may be OK. Windows could be problematic.

September 8, OVERVIEW COMPUTER IMAGING COMPUTER VISIONIMAGE PROCESSING

September 8, 19986

7 TIME VOLTAGE X X X X One Pixel One Scanline IMAGE

September 8, ORGANIZATION OF A 2D IMAGE Pixel Binary 1 bit Grey 1 byte Color 3 bytes

September 8, BINARY IMAGE

September 8, GREYSCALE IMAGE

September 8, COLOR IMAGE

September 8, RED GREEN BLUE yellow magenta cyan red green SCHEMES FOR REPRESENTING COLOR yellow cyan blue magenta INTENSITY RGB HSL hue saturation

September 8, IMAGE FILE FORMATS Why are there so many ? JPEG tiff gif PPM pgm BMP EPS

September 8,

September 8, OTHER IMAGING MODALITIES Medical Imaging Range sensing Thermal IR

September 8, CATSCAN IMAGE

September 8, RANGE IMAGE

September 8, THERMAL IMAGE

September 8, THE HUMAN EYE

September 8, THE HUMAN EYE

September 8, Raw Image Data (pixels) Preprocessing (images, subimages) Segmentation Edge Detection (spectrum, edges, lines) Feature Extraction Low Level High Level HIERARCHICAL IMAGE PYRAMID

September 8, CONTRAST ENHANCEMENT

September 8, THRESHOLDED SEGMENTATION

September 8, HOMEWORK ASSIGNMENT Due Wed. Sept. 16 Get familiar with a really useful image display tool called ‘XV’ Works on popular ‘Command Line’ environments such as UNIX and on DECs and SGIs. If you don’t already have this you can ftp from ftp://ftp.cis.upenn.edu/pub/xv

September 8, HOMEWORK ASSIGNMENT Due Wed. Sept. 16 Access image files by logging into cs.jhu.edu via anonymous ftp Display the image trees.gif and enhance contrast using ‘intensity correction’. Try to segment trees.gif into a binary image using ‘intensity correction’. Display desert.gif and modify individual RGB color bands.