Pinhole Camera2011 - Modeling the Pinhole Camera Projection...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
2/10/2011 1 Modeling the Pinhole Camera Projection, perspective, matrices Pinhole Cameras ` What do we mean by “modeling a camera”? ` What is the relation between a real world (3D) object and its 2D What is the relation between a real world (3D) object and its 2D image? ` Why modeling cameras? ` Stitch images ` Recover 3D information (stereo vision) ` Cameras are modeled as pinhole cameras. ` What is a pinhole camera?
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2/10/2011 2 ¾ Camera obscura dates from 15th Camera Obscura century. ¾ In 1490 Leonardo Da Vinci gave two clear descriptions of the camera obscura in his notebooks. Many of the first camera obscuras were large rooms like that illustrated by the Dutch scientist Reinerus Gemma-Frisius in 1544 for use in observing a solar eclipse: Pinhole Camera ` Pinhole camera is the abstraction. ` The human eye functions very much like a camera
Background image of page 2
2/10/2011 3 Single View Geometry COP origin principal point P ( X,Y,Z ) p ( x,y ) ` The camera coordinate system ` Put the optical center ( C enter O f P rojection) at the origin ` Put the image plane ( P rojection P lane) in front of the COP (Why?) (COP) Summary of the Camera Model ` Pinhole at (0,0,0), looking at points (X,Y,Z) = Z Y X P ` Image plane at Z = f =1 plane. ` Point (X,Y,Z) is imaged at intersection of: ` Line from (0,0,0) to (X,Y,Z), and ` the Z = 1 plane ` A camera is normalized if the units = y x p A camera is if the units are chosen so that the focal length f = 1. Camera Center of Projection
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
2/10/2011 4 Geometry for the Camera Model •So intersection point (x,y) has coordinates (fX/Z, fY/Z, 1) Z fY y Z fX x = = principal point Y = Z Y X f f Z fY fX y x 1 0 0 0 0 0 0 ~ 1 (x,y) = (fX/Z,fY/Z) is not linear in Z. Introduce “homogeneous” coordinates: Homogeneous Coordinates ` Represent 2D point using 3 numbers, instead of the usual 2 numbers. `
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 01/16/2012 for the course MAD 4103 taught by Professor Li during the Spring '11 term at University of Central Florida.

Page1 / 15

Pinhole Camera2011 - Modeling the Pinhole Camera Projection...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online