Efficient Color Boundary Detection with Color-opponent Mechanisms
description
Transcript of Efficient Color Boundary Detection with Color-opponent Mechanisms
![Page 1: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/1.jpg)
Efficient Color Boundary Detection with Color-opponent Mechanisms
CVPR2013 Posters
![Page 2: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/2.jpg)
Outline
Introduction Approach Experiments Conclusions
![Page 3: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/3.jpg)
Introduction
![Page 4: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/4.jpg)
Introduction
Propose a new framework for boundary detection in complex natural scenes based on the color-opponent mechanisms of the visual system.
Image source:http://en.wikipedia.org/wiki/Opponent_process
![Page 5: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/5.jpg)
Introduction One of the key limitations of opponent-based
approaches is that they are
blind to the luminance-defined boundaries. In order to obtain the complete contours of
objects, these methods had to spend extra computational cost to combine more cues to detect luminance boundaries [3].
[3] D. R. Martin, C. C. Fowlkes, and J. Malik, "Learning to detect natural image boundaries using local brightness, color, and texture cues," IEEE Trans. on PAMI, vol. 26, pp. 530-549, 2004.
![Page 6: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/6.jpg)
Introduction Simulate the biological mechanisms of
color information processing along the Retina-LGN-Cortex visual pathway
Image source:http://en.wikipedia.org/wiki/Opponent_process
![Page 7: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/7.jpg)
Introduction
Image source:[20] S. G. Solomon and P. Lennie, "The machinery of colourvision," Nature Reviews Neuroscience, vol. 8, pp. 276-286, 2007.
![Page 8: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/8.jpg)
Introduction
Color Mechanisms in the Visual System. Properties : 1. Trichromacy. 2. Two opponent channels. 3. Color opponency.
![Page 9: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/9.jpg)
Approach
Boundary Detection System : 1.Cone Layer 2.Ganglion/LGN Layer 3.Cortex Layer
![Page 10: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/10.jpg)
A feedforward hierarchical system
![Page 11: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/11.jpg)
1.Cone Layer
Type II cells in the ganglion/LGN layer is mainly for the perception of color region.
Four channels: red (R), green (G), blue (B) and yellow (Y) components, where Y = (R+G)/2.
Gaussian filters are used to simulate the receptive field of the cones in the retina.
Outputs:
![Page 12: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/12.jpg)
Approach
Boundary Detection System : 1.Cone Layer 2.Ganglion/LGN Layer 3.Cortex Layer
![Page 13: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/13.jpg)
2.Ganglion/LGN Layer
Single-opponent cells in ganglion/LGN layer areimportant for separating color and achromatic information,which is clearly shown by Equation 1.
w1 > 0 and w2 < 0 response : R-on/G-off cellsw1 < 0 and w2 > 0 response : R-off/G-on cells
![Page 14: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/14.jpg)
Approach
Boundary Detection System : 1.Cone Layer 2.Ganglion/LGN Layer 3.Cortex Layer
![Page 15: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/15.jpg)
3.Cortex Layer
In the cortex layer of V1, the receptive fields of most color- and color-luminance-sensitive neurons are both chromatically and spatially opponent.
![Page 16: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/16.jpg)
3.Cortex Layer
![Page 17: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/17.jpg)
3.Cortex Layer
The boundary responses at each orientation is given by (6)
![Page 18: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/18.jpg)
3.Cortex Layer
The boundaries are detected in four channels (i.e., R+ wG, wR+ G, B+ wY and wB+Y ) with Equations 1-8.
![Page 19: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/19.jpg)
Experiments
![Page 20: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/20.jpg)
Experiments
![Page 21: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/21.jpg)
Experiments
![Page 22: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/22.jpg)
Experiments
![Page 23: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/23.jpg)
Experiments
![Page 24: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/24.jpg)
Experiments
![Page 25: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/25.jpg)
Experiments
![Page 26: Efficient Color Boundary Detection with Color-opponent Mechanisms](https://reader035.fdocuments.net/reader035/viewer/2022070403/568139ae550346895da14923/html5/thumbnails/26.jpg)
Conclusions
1. Presented a novel biologically plausible computational model for contour detection of color images.
2. Our model exhibits excellent capability of detecting both color and luminance boundaries synchronously in a time-saving manner.