Chapter 7. Image Restoration (복원)

7.1 Median Filter(Denoise filter)

필터 중간 값으로 대체

7.2 Bilateral Filter(Denoise filter)

양방향 필터

파라미터 = Domain(=x,y좌표) + Range(=color)

강사 추천 알고리즘

• Adaptive Bilateral Filfer : 엣지의 방향을 고려한 개선 버젼

7.3 Deblurring(Restoration)

Remove or minimize the degradation in image

Unsharp mask로 처리 불가

Deconvolution/Deblurring problem

Methodology

1. Inverse filtering
2. Wiener filtering (Minimum mean square Error)
3. Constrained Least Squares(Regularization)
   • Regularized(High pass operator)
   • Bayesian(Prior model)

Degradation Function

• Blurring + noise
• PSF: Point Spread Function을 구하는 것이 중요함
  • Blurring models
  • $NxN$ uniform/Gaussian matrix
• Film gain Noise

(1) Inverse Filter

Reciprocal filter in the frequency domain

(2) Wiener filtering

Minimum mean square Error

(3) Least Squares Method

Pseudo-inverse Restoration??