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Step 6Capture and Decoding
Capture
With everything in place and calibrated, set your resolution to 1024x768 and open up the three cosine images and display them full screen, one at a time. Most operating systems have a built in image viewer that will let you use "slide show" mode and step forward manually. Zoom in your camera if necessary. Focus the projector on the subject, not behind them. Try to match the example images as much as possible.
Decode Setup
Once captured, transfer your images to the computer and resize them, reorienting them to portrait if necessary. 480x640 is a good size to start with. That might sound small, but remember: this is 300k points, or 600k triangles! Rename the images to "phase1.jpg", "phase2.jpg", and "phase3.jpg" and replace the example images. Make sure the images are in order. It's not important which one comes first, just that the pattern moves gradually in 2π/3 steps from image to image.
Decode Parameters
There are three decoding parameters: noise threshold, zskew, and zscale. Both zskew and zscale are dependent on the projector-camera configuration, and the noise threshold depends on the brightness of the subject as well as the ambient light. In other words, once your camera and projector are in place, you only need to tweak zskew and zscale once. zskew and zscale are related to the two measurements described in Step 1 (distance between camera and projector, and angle between camera and projector).
First tweak the noise threshold so that anything that's too dark to decode doesn't affect the decoding. Anywhere from 5-20 is a good starting point. Then modify the zscale so the points have some depth. Make sure the depth is in the right direction, and that your subject isn't flipped left-right (or really inside-out, like a mirror). Finally, modify zskew so the points are slanted correctly. If your camera is looking down slightly towards a vertical wall, the wall should lean forward slightly. Changing the decoding parameters is an iterative process: sometimes you have to get one right before you can see how to change the others.
With everything in place and calibrated, set your resolution to 1024x768 and open up the three cosine images and display them full screen, one at a time. Most operating systems have a built in image viewer that will let you use "slide show" mode and step forward manually. Zoom in your camera if necessary. Focus the projector on the subject, not behind them. Try to match the example images as much as possible.
Decode Setup
Once captured, transfer your images to the computer and resize them, reorienting them to portrait if necessary. 480x640 is a good size to start with. That might sound small, but remember: this is 300k points, or 600k triangles! Rename the images to "phase1.jpg", "phase2.jpg", and "phase3.jpg" and replace the example images. Make sure the images are in order. It's not important which one comes first, just that the pattern moves gradually in 2π/3 steps from image to image.
Decode Parameters
There are three decoding parameters: noise threshold, zskew, and zscale. Both zskew and zscale are dependent on the projector-camera configuration, and the noise threshold depends on the brightness of the subject as well as the ambient light. In other words, once your camera and projector are in place, you only need to tweak zskew and zscale once. zskew and zscale are related to the two measurements described in Step 1 (distance between camera and projector, and angle between camera and projector).
First tweak the noise threshold so that anything that's too dark to decode doesn't affect the decoding. Anywhere from 5-20 is a good starting point. Then modify the zscale so the points have some depth. Make sure the depth is in the right direction, and that your subject isn't flipped left-right (or really inside-out, like a mirror). Finally, modify zskew so the points are slanted correctly. If your camera is looking down slightly towards a vertical wall, the wall should lean forward slightly. Changing the decoding parameters is an iterative process: sometimes you have to get one right before you can see how to change the others.
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If you can't see the file extensions under windows, here is a tutorial.
If it's a newer camera, it can probably resize the photos in-camera, or just take smaller photos too.