Επεξεργασία Εικόνας

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Επεξεργασία Εικόνας
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Επεξεργασία Εικόνας. Τι είναι εικόνα;. Για τους σκοπούς μας, μια εικόνα είναι: Ένας 2D χώρος Με δείγματα σε τακτά χρονικά διαστήματα (σχεδόν πάντα σε ευθύγραμμο πλέγμα) - PowerPoint PPT Presentation

Transcript of Επεξεργασία Εικόνας

  • , : 2D ( ) , , opacity ( )

    :1 (B & W Grayscale)3 (, , )4 (, , , Alpha)5 ( ) ;

  • channel. ChannelsBlue Channel of Image, 1 sample per pixelGreen Channel of Image, 1 sample per pixelRed Channel of Image, 1 sample per pixel3 samples per pixel

  • R, G, B , , Alpha 0 1 1 pixel 0 pixel Alpha Channel(=0.6)

  • : : .

  • : (.., Corel Painter, Microsoft) : " , : 1:

  • , , , ., , : masking ( , ) blurring sharpening / antialiasing 2 Preprocessing

  • Mapping , :Stretching (): 3 Mapping

  • Art effectsPosterizing "out-of-focusimpressionistTexturizing B & W 4 Postprocessing

  • / HSV / 3D renderer 5

  • pixels

  • , . , MRI

    MRI Original MRI Image of a Dog HeartEdge Detection Image

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  • Reuters photo of Beirut

    Chinese press photo of Tibet railway Tom Hanks and JFK

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  • 3 - , T Boris , halftoning . Lars Lars Boris

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  • , . , camera-to-reaction , , , , .. ,

    Computer Vision

  • : : . (.., , ) UIComputer Vision

  • pixel Jaggies (aliasing) , !

    Jaggies Aliasing(a) Standard midpoint line on a bilevel display. (b) Same line on a display that has twice the linear resolution

  • Midpoint : pixel (0

  • pixel pixel / - , pixel Antialiasing

  • W (x, y) dA (x, y) pixel, :

    Box Filter W(x, y) dAW

  • - dA pixel W

  • 2-unit circular support of filterPixel center (+)Area of overlap between support and primitiveDifferential area dA2PrimitiveDifferential area dA1 W

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  • for each pixel pplace filter centered over p;for each pixel q under filterweight = filter value over q;intensity_p += weight * intensity_q;

    aliased antialiased

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  • Scale Aliasing

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  • Low-Pass Filtering (Spatial Domain)

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  • h (x) x f (x) g(x) g(x) g (x) x: x g (x) = g (x-) x h (x) f (x)Convolution ()

  • Convolution11111111111111111111+11111234321f(x) * f(x)*

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    Sinc 3D

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  • Filtering

  • Image Scaling(includes sampling)

  • Mapping = N pixels M pixels. : 10 x 10 pixels : 15 x 15 pixels 15 x 15 10 x 10 pixels

  • Scaling pixel pixel , pixel pixels; "" . , , - , 10 x 10 pixels

  • Re-Sampling

  • Re-Sampling

  • Scaling

  • Image AcquisitionImage RestorationMorphological ProcessingSegmentation

    Object Recognition

    Image EnhancementRepresentation & DescriptionColor Image ProcessingImage Compression

  • Image AcquisitionImage RestorationMorphological ProcessingSegmentationObject RecognitionImage EnhancementRepresentation & DescriptionColor Image ProcessingImage Compression

  • Image AcquisitionImage RestorationMorphological ProcessingSegmentationRepresentation & DescriptionImageEnhancementObject RecognitionColor Image ProcessingImage Compression

  • Image AcquisitionImage RestorationMorphological ProcessingSegmentationObject RecognitionImage Enhancement

    Representation & Description

    Color Image ProcessingImage Compression

  • Image AcquisitionImage RestorationMorphological ProcessingSegmentationRepresentation & DescriptionImage EnhancementObject RecognitionColor Image ProcessingImage Compression

  • Image AcquisitionImage RestorationMorphological ProcessingSegmentationObject RecognitionImage EnhancementRepresentation & DescriptionColor Image ProcessingImage Compression

  • Image AcquisitionImage RestorationMorphological ProcessingSegmentationImage EnhancementColor Image ProcessingImageCompressionRepresentation & DescriptionObject Recognition

  • Image AcquisitionImage RestorationMorphological ProcessingSegmentationObjectRecognitionImage EnhancementRepresentation &DescriptionColor Image ProcessingImage Compression

  • Image AcquisitionImage RestorationMorphological ProcessingSegmentationObject RecognitionImage EnhancementRepresentation & DescriptionColor Image ProcessingImage Compression

  • Image AcquisitionImage RestorationMorphological ProcessingSegmentationObjectRecognitionImage Enhancement

    Representation & Description

    Color Image ProcessingImage Compression

  • 1. Image Restoration

  • Image Colorization

  • Image Enhancement

  • Face Detection

  • Face Tracking

  • Face Morphing

  • Finger Print Recognition

  • Personal Identification Using Iris Recognition

    *************Information on Michael Blacks Commendation:http://www.cs.brown.edu/news/2007/0423.commendation.html*******Sources for Tibet Railway Info:http://in.reuters.com/article/lifestyleMolt/idINPEK35580420080218http://s.wsj.net/article/SB120363429707884255.html?mod=fpa_editors_picks

    ***********************************************Different problem: image scaling -> Back to image scaling ********************Morphing: the smooth transformation of one image into another by computer.**