1 / 14

Image Filtering with GLSL

Image Filtering with GLSL. DI1.03 蔡依儒. Outline. Convolution Convolution implementation using GLSL Commonly used convolution filter Mean Filter Gaussian Filter Laplacian Filter Sharpness Filter. Convolution 1. Convolution

thora
Télécharger la présentation

Image Filtering with GLSL

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Image Filtering with GLSL DI1.03 蔡依儒

  2. Outline • Convolution • Convolution implementation using GLSL • Commonly used convolution filter • Mean Filter • Gaussian Filter • Laplacian Filter • Sharpness Filter

  3. Convolution1 • Convolution • an operation in which the final pixel is the weighted sum of the neighboring pixels • Convolution kernel • a matrix which gives some weight to each one of the neighbor pixels • filter, mask, kernel, template, or window

  4. Convolution2

  5. Convolution implementation using GLSL

  6. Mean Filter • Most commonly used for the image noise elimination • eliminating pixel values which are unrepresentative of their surroundings

  7. Gaussian Filter1 • A kind of Lowpass filters • Used to blur an image and remove detail and noise 1/16 2/16 1/16 2/16 4/16 2/16 2/16 1/16 1/16

  8. Gaussian Filter2

  9. Gaussian Filter3 • Results of smoothing with square filter masks of sizes n = 3, 5, 9, 15, and 35, respectively • The black squares at the top are of sizes 3, 5, 9, 15, 25, 35, 45, and 55 pixels, respectively

  10. Laplacian Filter1 • Used for the image edges detection 0 1 0 1 -4 1 1 0 0

  11. Laplacian Filter2

  12. Sharpness Filter • Used to increase and to make stand out the details of an image 0 -1 0 -1 -1 -1 -1 -1 5 9 -1 -1 -1 -1 0 0 -1 -1

  13. 馬賽克

  14. Reference • http://www.ozone3d.net/tutorials/image_filtering.php • http://www.cee.hw.ac.uk/hipr/html/filtops.html • Digital Image Processing 2nd Edition • by Gonzalez and Woods • Prentice Hall • http://big5.yesky.com/b5/www.yesky.com/SoftChannel/72342371928702976/20041028/1869312.shtml

More Related