CEN-444 Digital Image
Processing
(Spring 2023)
Department of Computer Engineering
Bahria University Karachi Campus
Lecture Slides Set 03
Image Interpolation
• Interpolation is a type of estimation, a method of constructing
(finding) new data points based on the range of discrete set of known
data points
Image Interpolation
Image Interpolation
Image Interpolation
Image Interpolation
Image Interpolation
Image Interpolation
Image Interpolation
Image Interpolation
Image Interpolation
Bilinear Interpolation
Basic Relationship of Pixels
Neighbors of a Pixel
Neighbors of a Pixel
Neighbors of a Pixel
Connectivity
Adjacency
Adjacency
Connectivity
Connectivity
Path
Path
Distance
For pixel p, q, and z with coordinates (x,y), (s,t) and (u,v),
D is a distance function or metric if
w D(p,q) 0
(D(p,q) = 0 if and only if p = q)
w D(p,q) = D(q,p)
w D(p,z) D(p,q) + D(q,z)
Example: Euclidean distance
De ( p, q)  ( x - s)2 + ( y - t )2
Distance (cont.)
D4-distance (city-block distance) is defined as
D4 ( p, q)  x - s + y - t
2
2
2
1
2
1
0
1
2
1
2
2
2
Pixels with D4(p) = 1 is 4-neighbors of p.
Distance (cont.)
D8-distance (chessboard distance) is defined as
D8 ( p, q)  max( x - s , y - t )
2
2
2
2
2
2
1
1
1
2
2
1
0
1
2
2
1
1
1
2
2
2
2
2
2
Pixels with D8(p) = 1 is 8-neighbors of p.