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Computer Science
Computer Vision
Image Processing
1. Fundamentals of Digital Images
2. Intensity Transformations and Point Operations
3. Spatial Filtering
4. Frequency Domain Processing
5. Image Restoration and Denoising
6. Image Segmentation
7. Morphological Image Processing
8. Color Image Processing
9. Image Compression
10. Advanced Topics
Frequency Domain Processing
The Fourier Transform
One-Dimensional Fourier Transform
Continuous Fourier Transform
Discrete Fourier Transform
Properties and Interpretation
Two-Dimensional Discrete Fourier Transform
Mathematical Formulation
Forward Transform
Inverse Transform
Implementation for Images
Properties of the 2D DFT
Periodicity
Symmetry Properties
Translation Property
Rotation Property
Scaling Property
Linearity
The Convolution Theorem
Spatial Convolution as Frequency Multiplication
Computational Advantages
The Fast Fourier Transform
Algorithm Overview
Divide-and-Conquer Approach
Butterfly Operations
Computational Advantages
Complexity Reduction
Memory Requirements
Implementation Considerations
Power-of-Two Sizing
Zero-padding Strategies
Filtering in the Frequency Domain
Basic Steps of Frequency Domain Filtering
Image Preprocessing
Forward Fourier Transform
Filter Application
Inverse Fourier Transform
Post-processing
Correspondence Between Spatial and Frequency Filters
Low-pass Filter Equivalence
High-pass Filter Equivalence
Impulse Response Relationship
Frequency Response Analysis
Frequency Domain Filters
Low-Pass Filters
Ideal Low-Pass Filters
Sharp Cutoff Characteristics
Ringing Artifacts
Butterworth Low-Pass Filters
Order Parameter Effects
Smooth Transition
Gaussian Low-Pass Filters
No Ringing Artifacts
Separability Properties
High-Pass Filters
Ideal High-Pass Filters
Sharp Cutoff Characteristics
Butterworth High-Pass Filters
Order Parameter Effects
Gaussian High-Pass Filters
Smooth Characteristics
Band-Pass and Band-Reject Filters
Band-Pass Filter Design
Frequency Range Selection
Band-Reject Filter Design
Notch Filter Implementation
Applications in Noise Removal
Notch Filters
Periodic Noise Removal
Multiple Notch Implementation
Optimum Notch Filtering
Homomorphic Filtering
Illumination-Reflectance Model
Multiplicative Model
Logarithmic Transformation
Frequency Domain Separation
Low-frequency Illumination
High-frequency Reflectance
Applications in Image Enhancement
Dynamic Range Compression
Contrast Enhancement
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5. Image Restoration and Denoising