Chapter 2: Image processing and computer vision Camera models and parameters Ch2. Cameras v0.b2
Chapter 2: Image processing and computer vision Camera models and parameters Ch2. Cameras v.0.b2 1
Will Learn these in this chapter Mathematical model of a camera Intrinsic(static)parameters of a camera(Mint3x3 Focal length(f) for fixed focal length, non-zoomed cameras Image center(Ox, Oy) Pixel width/height(Sx, Sy) Extrinsic(dynamic) parameters of a camera ext 3 Rotation(R)and Translation (T) of a camera Characteristics of r and t Image formation and projection matrix P3x4 Ch2. Cameras v0.b2
Will Learn these in this chapter Mathematical model of a camera Intrinsic (static) parameters of a camera (Mint3x3) • Focal length (f) for fixed focal length, non-zoomed cameras • Image center (Ox,Oy) • Pixel width/height (Sx,Sy) Extrinsic (dynamic) parameters of a camera (Mext3x4) Rotation (R) and Translation (T) of a camera Characteristics of R and T Image formation and projection matrix P3x4 Ch2. Cameras v.0.b2 2
Motivations Digital cameras are everywhere Develop applications for cameras Help to choose a good camera Ch2. Cameras v0.b2
Motivations • Digital cameras are everywhere. • Develop applications for cameras. • Help to choose a good camera. Ch2. Cameras v.0.b2 3
Camera model) Intrinsic parameters I extrinsic parameters I projection Bd to 2D projection http://upload.wikimediaorg/wikipedia/en/8/81/pinhole-camera.png Pinhole Camera Perspective model U=F* X/Z V=F*Y/Z Screen or ccd World https:lenswikipediaorg/wiki/charge-couplEddevicecenter sensor Y V 素v Screen Or Thin lens CCD Ch2. Cameras v0.b2 or a pin hole sensor
Camera model | Intrinsic parameters | extrinsic parameters | projection 3D to 2D projection Perspective model u=F*X/Z v=F*Y/Z F Z Y v World center F Thin lens or a pin hole Virtual Screen or CCD https://en.wikipedia.org/wiki/Charge-coupled_device sensor Real Screen Or CCD sensor Pinhole Camera http://upload.wikimedia.org/wikipedia/en/8/81/Pinhole-camera.png v Ch2. Cameras v.0.b2 4
Camera model) Intrinsic parameters I extrinsic parameters I projection Perspective World Coordinates Projective Modelmat t=l On=10.0.0 (World center) (,Y, Z) V-aXIs image R Yc-axis Camera u Coordinates Zc-axis Principal axis≤- 0,0,0) c(Image center(Camera center) u-aXIs length C-aXIs Ch2. Cameras v0.b2
Camera model | Intrinsic parameters | extrinsic parameters | projection Perspective Projective • Model M at t=1 c (Image center, ox ,oy ) F=focal length image Oc=(0,0,0) (Camera center) Yc-axis Zc-axis Xc-axis v-axis u-axis (X,Y,Z) (u,v) Camera Coordinates. World Coordinates Z Yw w Xw Rc , Tc Principal axis OW=(0,0,0) (World center) Ch2. Cameras v.0.b2 5