Photometric Invariance from Color Ratios Theo Gevers Color
- Slides: 25
Photometric Invariance from Color Ratios Theo Gevers Color in Computer Vision – 2019
Table of Contents Color in Computer Vision – 2019
Introduction Color in Computer Vision – 2019
Color in Computer Vision – 2019
What is a Mondrian? Color in Computer Vision – 2019
5. 1 Illuminant-Invariant Color Ratios Color in Computer Vision – 2019
Color in Computer Vision – 2019
Color in Computer Vision – 2019
Color in Computer Vision – 2019
5. 2 Illuminant-Invariant Edge Detection Note that here “R” denotes the Red channel response, which is being used as an example. Color in Computer Vision – 2019
? ? Note that this is a significant change in notation. In Eq. 5. 16, “Rx_1” denotes the Red channel response at spatial position x_1. In Eq. 5. 17, “Rx” denotes the spatial derivative at an unspecified spatial position. Note: This follows from the rule for differentiating the logarithm, stated at the top of this page. Color in Computer Vision – 2019
Color in Computer Vision – 2019
5. 3 Blur-Robust and Color Constant Image Description Color in Computer Vision – 2019
What is a Gaussian Derivative? l Consider a signal g(x) that has been smoothed by convolution with a Gaussian kernel with standard deviation sigma. l where l Then From: https: //staff. fnwi. uva. nl/r. vandenboomgaard/IPCV 20172018/Lecture. Notes/IP/Local. Structure/Gaussian. Derivatives. html (University of Amsterdam) Color in Computer Vision – 2019
Color in Computer Vision – 2019
Color in Computer Vision – 2019
Color in Computer Vision – 2019
5. 4 Application: Image Retrieval Based on Color Ratios Color in Computer Vision – 2019
Example Images from Simon Fraser Dataset Color in Computer Vision – 2019
Robustness to Illuminant Color in Computer Vision – 2019
Results from Image Retrieval Experiment Color in Computer Vision – 2019
Robustness to Gaussian Blur Color in Computer Vision – 2019
Robustness to Real-World Blurring Effects Color in Computer Vision – 2019
Example Images Used for Real. World Blurring Experiment Color in Computer Vision – 2019
Results from Image Retrieval Experiment Color in Computer Vision – 2019