vault backup: 2023-03-30 13:19:09

content/notes/10-3d-Cameras.md

@@ -0,0 +1,40 @@
+---
+title: "10-3d-Cameras"
+tags: 
+- lecture
+- cosc342	
+---
+
+
+CAMERAS AND PROJECTIONS 
+- Cameras project the 3D world onto a 2D image 
+	- Input is 3D points:  (𝑥, 𝑦, 𝑧)
+	- Output is 2D points: (𝑢, 𝑣)
+![matrix|100](https://i.imgur.com/bMo02GG.png)
+	- What form should P have?
+> [!INFO] need to apply a transformation to convert 3d coords to 2d coords
+> P should be a 3 row and 4 column matrix
+
+WHICH CUBE LOOKS RIGHT?
+![](https://i.imgur.com/sYpeZvX.png)
+> [!INFO] each cube is a projection of 3d points onto 2d space.
+> middle cube is perspective transformation
+> left is isometric
+> right is orthographic
+
+ORTHOGRAPHIC PROJECTION 
+- Simple way to go from 3D to 2D 
+- Delete one dimension! 
+- Deleting X projects to the X -Y plane 
+![matrix equation](https://i.imgur.com/J2fPAp5.png)
+- This is not how our eyes work
+> [!INFO] z coordinate is removed since the third column is zero
+
+PERSPECTIVE PROJECTION 
+- Our view of the world: 
+	- Distant objects looks smaller 
+	- Parallel lines in 3D converge in 2D 
+- The pinhole camera 
+	- A simple, but useful, model 
+	- There is a central point of projection (the pinhole, often a lens in reality) 
+	- Light travels from the world, through the pinhole, to the image plane

content/notes/cosc-342.md

@@ -27,6 +27,7 @@ tags:
 - [x] [[06-homographies]]
 - [[08-visual-tracking-and-matching]]
 - [[09-3d-geometry]]
+- [[10-3d-Cameras]]
 
 # Info