vault backup: 2023-03-16 13:24:33

content/notes/06-homographies.md

@@ -0,0 +1,39 @@
+---
+title: "06-homographies"
+tags: 
+- lecture
+- cosc342
+---
+
+Homographies and mosaics
+- A homography* is: 
+	- A linear map between two planes (or views of a plane) 
+	- A 3 x 3 matrix, up to a scale 
+- Two images of a scene are related by a homography 
+	- If the scene is planar, or 
+	- If the camera only rotates
+- ![|300](https://i.imgur.com/Rfh38wF.png)
+
+Homographies for planar scenes
+- Take a line in one view 
+- This projects to a plane 
+- That intersects the scene (another plane) at a line 
+- That projects to a line in the other image 
+- So lines are preserved
+- ![|300](https://i.imgur.com/YZPAFl6.png)
+
+> [!INFO] can create a "straight" view of a picture! 
+
+[|300](https://i.imgur.com/BEjOoFL.png)
+
+> [!INFO] homography: maps points from one image to another
+
+> [!INFO] rephotography, mathing old photographs onto the current view of the user
+
+
+
+homography for rotating camera
+![|300](https://i.imgur.com/L6MqmUD.png)
+
+
+> [!INFO] K matric describe parameters of camera. R matric describes rotation of camera. T is zero because the camera is only rotating. H is the homograhy matrix

content/notes/cosc-342.md

@@ -22,6 +22,7 @@ tags:
 - [x] [[03-2d-transforms]]
 - [[04-mosaicing]]
 - [x] [[05-feature-description-and-matching]]
+- [ ] [[06-homographies]]
 
 # Info