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6230 - Coggle Diagram

- - - - example
        
        noise removal
        
        enhancement: denoising
        
        enhancement: Laplacian
      - image compression
        
        denefinition
        
        benefits
      - applications
        
        medical research
        
        environmental control
        
        statellite imaging
        
        false colour images
        
        image-based diagnosis
        
        forensics & enforcement
        
        video production
        
        histograms
        
        segmentation
        
        boundary issues
        
        intelligent browsing
        
        content based image retrieval
        
        metadata based
        
        computer vision
        
        multiple images and camera arrays
        
        HDR
        
        Panoramic mosaics
        
        Panoramic distortion
        
        refocusing and light field rendering
        
        extended depth of field
  - - - continuous image representation
      - discrete
      - pictorial intensity representation
      - pictorial colour representation
      - pixel
      - an intuitive definition of image
    - - sampling
        
        image representation-pixels
        
        digital images
        
        image digitization
        
        scanline
        
        low resolution
        
        methods
        
        uniform
        
        sampling effect
        
        adaptive
        
        relationships between pixels
        
        4-neighbourhood
        
        8-neighbourhood
      - quantization
        
        intensity resolution*
        
        dithering and halftoning
        
        quantization methods
        
        non-uniform quantization
        
        quantizing colour images
        
        LUT
        
        Gamma transformation
      - digital image quality factors
        
        spatial resolutin
        
        intensity
      - 1
        
        zooming
        
        pixel replication(NN)
        
        Bilinear interpolation
        
        general interpolation
        
        forward mapping
        
        backward interpolation
        
        shrinking(can be seen as under sampling)
        
        sub-sampling
        
        up-sampling
  - - - encapsulated information
        
        constrast（灰方块颜色相同，周围颜色不同）（通过直方图判断）
        
        brightness（亮度范围：0-255）
      - detect bad exposure using histograms
      - reflect the pixel distribution, not the spatial distribution
    - - many to one
      - invertible（不同图像可能有相同直方图）
      - is invariant to certain operations（rotation,scaling,mirroring,skew）
    - - lighting, contrast,dynamic range, and saturation effects,but not the actual color distribution
        
        individual color channel histograms
        
        intensity histogram
    - - definition
      - measurements with histograms: formula
    - - histogram equalization
        
        objective
        
        application
      - transformation of probability density*
        
        continuous histogram equalization
        
        discrete histogram equalization
- - - - algebraic operations
        
        image subtraction
        
        background subtraction
        
        dege detection
        
        image averaging
        
        property
        
        non-invertible
        
        clipping
        
        normalization
        
        example
        
        addition
        
        noise removal
        
        finnite-difference filters(理解)
        
        gradient（看一阶的最大最小值检测边缘，垂直于边缘）
        
        gradirnt magnitude
        
        directional derivative(steerability)
    - - spatial transformation
        
        coordinate system
        
        affine transformation
        
        collinearity/ratios of distances(变换后中点仍为中点)
        
        homogeneous coordinates(坐标转化)
        
        scaling
        
        ratation
        
        shear
        
        rotate around
        
        X
        
        Y
        
        Z
        
        compound transformation
        
        right to left
        
        inverse warping
        
        spatial relationship
        
        continuous
        
        discontinuous
      - intensity interpolation
  - - - JND
      - lightness
        
        embodies the achromatic notion of perceived intensity of a reflecting object
      - brightness(self-luminous ojbect自发亮的物体)
    - - wavelengths(400-700mm)
      - intensity
      - quality: radiance, luminance, brightness(光谱颜色spectral由单一波长组成)
    - - retins
        
        rods(not)
        
        cones
        
        3 types
      - HVS
        
        more sensitive to brightness than colour