Does Kinect Infrared View Have an offset with the Kinect Depth View

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Depth and Color streams are not taken from the same point so they do not correspond to each other perfectly. Also they FOV (field of view) is different.

  1. cameras

    • IR/Depth FOV 58.5° x 45.6°
    • Color FOV 62.0° x 48.6°
    • distance between cameras 25mm

  2. my corrections for 640×480 resolution for both streams

    if (valid depth)
 {
 ax=(((x+10-xs2)*241)>>8)+xs2;
 ay=(((y+30-ys2)*240)>>8)+ys2;
 }
    • x,y are in coordinates in depth image
    • ax,ay are out coordinates in color image
    • xs,ys = 640,480
    • xs2,ys2 = 320,240

    as you can see my kinect has also y-offset which is weird (even bigger then x-offset). My conversion works well on ranges up to 2 m I did not measure it further but it should work even then

  3. do not forget to correct space coordinates from depth and depth image coordinates

    pz=0.8+(float(rawdepth-6576)*0.00012115165336374002280501710376283);
px=-sin(58.5*deg*float(x-xs2)/float(xs))*pz;
py=+sin(45.6*deg*float(y-ys2)/float(ys))*pz;
pz=-pz;
    • where px,py,pz is point coordinate in [m] in space relative to kinect

    I use coordinate system for camera with opposite Z direction therefore the negation of sign

PS. I have old model 1414 so newer models have probably different calibration parameters

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