a new texture descriptor: composite sub_band gradient vector 2006.3.30
Post on 19-Dec-2015
220 views
TRANSCRIPT
![Page 1: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/1.jpg)
A New Texture Descriptor: Composite Sub_band
Gradient Vector
2006.3.30
![Page 2: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/2.jpg)
Texture Analysis by Gradient-Based Feature Gradient operator (Sobel) reflect the magnitud
e and direction.
Summing up the magnitude in the same direction.
Every successive k(=10) directions grouped together
)(tan),( 1
Gx
Gyyx
GyGxf
![Page 3: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/3.jpg)
Euclidean distance: measure the difference between two gradient vector.
d
ii babadist1
2)(),(
![Page 4: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/4.jpg)
![Page 5: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/5.jpg)
Composite Subband Gradient Vector drawback
![Page 6: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/6.jpg)
LL sub-image: Both horizontal and vertical direction have low-frequencies.
LH sub-image: Horizontal direction has low-frequencies and vertical direction has high-frequencies
![Page 7: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/7.jpg)
HL sub-image: Horizontal direction has high-frequencies and vertical direction has low-frequencies.
HH sub-image: Both horizontal and vertical direction have high-frequencies.
![Page 8: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/8.jpg)
SGV1 be the sub-image LL SGV2 be the sub-image LH SGV3 be the sub-image HL SGV4 be the sub-image HH
CSGV = SGV1|| SGV2|| SGV3|| SGV4(where || is append operator)
CSGV is called Composite Subband Gradient Vector
![Page 9: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/9.jpg)
(g)=>(h)
(g)=>(i)
Dist.
5.5099 16.6057
![Page 10: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/10.jpg)
Segmentation using Reduced-Length CSG Vectors
Segmentation process into three stages:(1).split stage.(2).merge stage.(3).boundary stage.
Assume that an image I is of size m*m pixels
![Page 11: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/11.jpg)
Split stage.
![Page 12: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/12.jpg)
![Page 13: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/13.jpg)
Merge stage.
![Page 14: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/14.jpg)
![Page 15: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/15.jpg)
Boundary stage.
![Page 16: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/16.jpg)
![Page 17: A New Texture Descriptor: Composite Sub_band Gradient Vector 2006.3.30](https://reader036.vdocuments.mx/reader036/viewer/2022062516/56649d365503460f94a0da40/html5/thumbnails/17.jpg)
Result(Split:0.1 Merge:0.7)