Elements of Biomedical Image Processing BMI 731 Winter 2005

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Elements of Biomedical Image ProcessingBMI 731
Winter 2005

• Kun Huang
• Department of Biomedical Informatics
• Ohio State University

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• Introduction to imaging processing
• Mathematical background
• Convolution and Fourier transform
• Filtering
• Image enhancement
• Noise removal
• Color correction and color space transform
• Feature extraction
• Edge, point, line (Hugh transform)
• 3-D reconstruction
• Radon transform

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• Image Processing what should be done?
• Image restoration and enhancement
• Feature extraction
• Pattern recognition

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• Mathematical Background
• Convolution
• 2-D convolution

1x28x915x47x714x5 16x313x620x122x8 575
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• Mathematical Background
• Fourier transform (FT)
• Mathematics
• 2-D FT

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• Mathematical Background
• Fourier transform (FT)
• Fast FT (FFT)

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• Mathematical Background
• Convolution and Fourier transform (FT)

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• Mathematical Background
• Filtering
• High-pass filter, low-pass filter, band pass
  filter
• Gradient filters

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• Mathematical Background
• Filtering
• Wiener filter and deblurring

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• Image Enhancement
• Denoise
• Averaging
• Median filter

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• Image Enhancement
• Denoise/restoration

From Gonzalez, Woods, and Eddins
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• Image Enhancement
• Color and intensity adjustment
• Histogram equalization

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• Image Enhancement
• Color space transform

RGB -gt HSV, HSL, YCbCr,
R 64 G 31 B 62
R 125 G 80 B 147
H 214 S 132 V 64
H 199 S 117 V 147
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• Feature Extraction
• Region detection morphology manipulation
• Dilate and Erode
• Open
• Erode ? dilate
• Small objects are removed
• Close
• Dilate ? Erode
• Holes are closed
• Skeleton and perimeter

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• Feature Extraction
• Edge detection
• Gradients
• Canny edge detector
• Gaussian smoothing
• Gradients
• Two thresholds
• Thinning

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• Feature Extraction
• Point detection
• Harris detector

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• Feature Extraction
• Radon transform
• Straight line detection
• Hugh transform

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• Feature Extraction
• Straight line detection
• Hugh transform

From Gonzalez, Woods, and Eddins
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• 2-D/3-D reconstruction
• Radon/inverse radon transforms and backprojection

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• Reference
• Digital Image Processing using Matlab
• By R.C.Gonzalez, R.E.Woods, and S.L.Eddins
• Published by Printice-Hall, 2004