Infinite Depth of Field Methodology

  1. Obtain an image-stack, by shooting N pictures, varying only the focus of the camera
  2. For each pixel (x, y), detirmine which of the N images has the pixel in sharpest focus
    1. Measure 1: Variance of image intensity over a neighborhood of k surrounding pixels
    2. Measure 2: Tenengrad Method - Sum of the intensity gradient over a neighborhood of k surrounding pixels (see Sobel kernels)
  3. Combine the sharpest pixels over all (x, y) to create an image with infinite depth of field

Download Files

Subject 1: Low angle chess game

Notes

Input Images

1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29

Output Images

Tenengrad Focus Measures

    
Tenegrad Focus Measure, Neighborhood k = 5

    
Tenegrad Focus Measure, Neighborhood k = 10

     
Tenegrad Focus Measure,Neighborhood k = 15

    
Tenegrad Focus Measure, Neighborhood k = 20

    
Tenegrad Focus Measure, Neighborhood k = 25

     
Tenegrad Focus Measure,Neighborhood k = 30

    
Tenegrad Focus Measure, Neighborhood k = 40

     
Tenegrad Focus Measure, Neighborhood k = 50

Variance Focus Measures

    
Variance Focus Measure, Neighborhood k = 2

    
Variance Focus Measure, Neighborhood k = 4

    
Variance Focus Measure, Neighborhood k = 6

    
Variance Focus Measure, Neighborhood k = 8

    
Variance Focus Measure, Neighborhood k = 10

    
Variance Focus Measure, Neighborhood k = 13

    
Variance Focus Measure, Neighborhood k = 16

    
Variance Focus Measure, Neighborhood k = 19

 

    
Variance Focus Measure, Neighborhood k = 25

    
Variance Focus Measure, Neighborhood k = 30

    
Variance Focus Measure, Neighborhood k = 40

    
Variance Focus Measure, Neighborhood k = 50