1 / 10

14. Warping

14. Warping. Image warping a kind of image processing that causes pixels to change their locations (geometric processing) a mapping function describes the relationship between the coordinates in a source and target image Homogeneous transform includes translation scaling rotation shear.

vondra
Download Presentation

14. Warping

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. 14. Warping • Image warping • a kind of image processing that causes pixels to change their locations (geometric processing) • a mapping function • describes the relationship between the coordinates in a source and target image • Homogeneous transform • includes • translation • scaling • rotation • shear

  2. 14.1 Translation (이동) • Translation matrix T | 1 0 Tx | | 0 1 Ty | | 0 0 1 |

  3. 14.2 Scaling (크기) • Scaling matrix S | Sx 0 0 | | 0 Sy 0 | | 0 0 1 |

  4. 14.3 Rotation (회전) • Rotation matrix R | cos -sin 0 | | sin cos 0 | | 0 0 1 |

  5. 14.4 Shear • Shear matrix Sh | 1 shx 0 | | shy 1 0 | | 0 0 1 |

  6. 적용 예 • 다각형 (polygon) 예 P2=(1,3) P1=(2,1) P0=(1,1)

  7. 14.6 Applying the transforms to an image • Applying 3*3 transform matrix to every pixel in the image • Forward mapping • pixel p에 transform matrix 적용하여 p’ 구함 (p’=T p) • p’의 실수 좌표를 정수로 rounding • target image에 hole (dark pixel) 발생하는 문제 source image target image

  8. 14.6 Applying the transforms to an image • Inverse mapping (destination scanning) • destination (target) image pixel (p’)에 대해 source image pixel (p)구함 • p = T-1 p’ • target image에 hole (dark pixel) 발생하는 문제 없음 source image target image

  9. 14.6 Applying the transforms to an image • 적용 예 • Rotation: Figure 14-6 • Scaling: Figure 14-7 • Shear: Figure 14-8 & 14-9

  10. 14.9 Effects • fishEye • Plate 14-2 • polar transform • Plate 14-3 • Square root transform • Plate 14-4 • Conformal mapping • Plate 14-6

More Related