2D Continuous Wavelet Transform

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2D Continuous Wavelet Transform

• Heejong Yoo(ECE)
• April 26, 2001

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Project Description

• The idea of this project is from the software of
  Crit-tech.com(Psilets 3.0) (www.crit-tech.com)

• Project Description
• Understand 1D, 2D DWT(FWT_PO.m, FWT2_PO.m in
  WaveLab)
• Understand 1D CWT(CWT.m in WaveLab)
• Develop 2D CWT algorithm for image processing at
  fixed scale

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CWT DWT
CWT DWT
1. Scale At any scale Dyadic scales
2. Translation At any point Integer point
3. Wavelet Any wavelet that satisfies minimum criteria Orthogonal, biorthogonal,
4. Computation Large Small
5. Detection Easily detects direction, orientation Cannot detect minute object if not finely tuned
6. Application Pattern Recognition Feature extraction Detection Compression De-noising Transmission Characterization
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Continuous Wavelet Transform
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2D Mexican Hat wavelet
Time domain
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2D Mexican Hat wavelet (Movie)low frequency ?
high frequency
ltTime Domain Waveletgt
ltFourier Domain Waveletgt
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(No Transcript)
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GUI based 2D CWT
This program follows the WaveLab
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Crit-tech Psilets 3.0 Output (1)
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Scale 38
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Scale 2
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Scale 1
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Crit-tech Psilets 3.0 Output (2)
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Scale 48
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Scale 3