efficient color boundary detection with color-opponent mechanisms
DESCRIPTION
Efficient Color Boundary Detection with Color-opponent Mechanisms. CVPR2013 Posters. Outline. Introduction Approach Experiments Conclusions. Introduction. Introduction. - PowerPoint PPT PresentationTRANSCRIPT
Efficient Color Boundary Detection with Color-opponent Mechanisms
CVPR2013 Posters
Outline
Introduction Approach Experiments Conclusions
Introduction
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
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.
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
Introduction
Image source:[20] S. G. Solomon and P. Lennie, "The machinery of colourvision," Nature Reviews Neuroscience, vol. 8, pp. 276-286, 2007.
Introduction
Color Mechanisms in the Visual System. Properties : 1. Trichromacy. 2. Two opponent channels. 3. Color opponency.
Approach
Boundary Detection System : 1.Cone Layer 2.Ganglion/LGN Layer 3.Cortex Layer
A feedforward hierarchical system
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:
Approach
Boundary Detection System : 1.Cone Layer 2.Ganglion/LGN Layer 3.Cortex Layer
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
Approach
Boundary Detection System : 1.Cone Layer 2.Ganglion/LGN Layer 3.Cortex Layer
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.
3.Cortex Layer
3.Cortex Layer
The boundary responses at each orientation is given by (6)
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.
Experiments
Experiments
Experiments
Experiments
Experiments
Experiments
Experiments
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.