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Image Processing I 15-463: Rendering and Image Processing Alexei Efros … with most slides shamelessly stolen from Steve Seitz and Gonzalez & Woods
Today ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Image Formation f(x,y) = reflectance(x,y) * illumination(x,y) Reflectance in [0,1], illumination in [0,inf]
Sampling and Quantization
Sampling and Quantization
What is an image? ,[object Object],[object Object],[object Object],[object Object],[object Object]
Images as functions
What is a digital image? ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Image processing ,[object Object],[object Object],[object Object],[object Object]
Point Processing ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]
Basic Point Processing
Negative
Log
Power-law transformations
Gamma Correction Gamma Measuring Applet: http:// www.cs.berkeley.edu/~efros/java/gamma/gamma.html
Image Enhancement
Contrast Streching
Image Histograms
Cumulative Histograms
Histogram Equalization
Histogram Matching
Match-histogram code
Neighborhood Processing (filtering) ,[object Object],[object Object],[object Object]
Programming Assignment #1 ,[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

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Point Processing

Notes de l'éditeur

  1. As opposed to [0..255]
  2. Render with scanalyze????
  3. Use photoshop to make something grayscale