"No one is harder on a talented person than the person themselves" - Linda Wilkinson ; "Trust your guts and don't follow the herd" ; "Validate direction not destination" ;

August 30, 2015

Video Analytics Class 2

My Notes
  • Linear Filter - Linear combination of neighbours
  • Box filter - All values constant [1's]
  • Corr-relation - Masked and Moved across Image
  • Gradient  - due to surface normal discontinuity, depth discontinuity, illumination discontinuity
  • LOG - Laplace of Gaussian. LOG capable of finding edges
  • Salt and Pepper Image - Image has random black and white 
  • Represent Image as a Matrix
  • Represent Image as a function
  • Point, local operations, histogram equalization, moving average model
  • Cross Correlation g = H X F
  • Gaussian filter (Removes High frequency, blurring, smoothens image)
  • Symmetric Matrix (When you shift rows into columns it would appear the same ( aij = aji, for all indices i and j) example link 
Convolution Basics
Programmatic Walkthru - link

From link 
From link

From Link

Convolution Applications
  • Smoother image
  • Gaussian (Point spread function)
  • Different Kinds of filter (Box, Gaussian filter)

Cross Correlation - Assess how similar are two different functions. Compares position by position. 
Correlation Walkthru

From Link 

Mathematics concepts to learn
  • Vector Product
  • Eigen Value decomposition
  • First Derivative, Second Derivative
Vertical and horizontal edge detection filters - Sobel, Roberts, Prewitt (Veritical, Horizontal, Diagonal edge detection filters).

Good Read Link
MIT Course Slides link

Related Reads

Happy Learning!!!

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