Poor Man scanner.

So take whatever object you want to scan.  And then buy another one so your son doesn’t get sad you put dots all over his ducky.  You can see him walk up in the background of this video :)  then put dots on the object in the way you want the point cloud data to be.  the higher the contrast the better.  Also if you paint the object a solid color it will make your life easier.   Film the object spinning very slowly.  You want to see a parallax shift between the dots and see all the dots.  I probably could have planed my rotation better.  This was just with a standard miniDV camera.  Take that footage you have and run it through your favorite compositing package.  and isolate just the image.  I did a combo of keys and color correction to isolate just the duck and to make the points more contrasty.  Also did some stuff to fix the miniDV color space.. No roto required. 

Render that out.  Take it into your favorite tracking software.  I love Syntheyes.  It’s extremely powerful and fast.  Also in makes this a poor man scanner.  Other packages would make it more expensive.  Anyway.  Run it through sytheyes.  It will do a good solve.  Go through and do the “add many trackers.”  But only try to add about 400.  Because you only want the dead on trackers.  So I decreased my error threshold and turned up the amount of time a tracker had to be on to be added.  That got me around 400.  Then I did Coalesce  nearby trackers.  Which basically makes trackers that are close the same tracker.  So if I track a dot on his wing, then it goes off frame and comes back on, it adds another tracker, so there are now two trackers in the same spot.  you only want one.  Each tracker is going to be a point on your point cloud.   My total number of trackers is now around 250.  Which is about how many dots I put on my duck.  Do another refine solve.  If you see a dot that did not get a tracker do a manual tracker on it for about 40 frames, that is enough for the software to decide where that point is in 3d.  It will give you another point.  Select all the trackers.  Convert to mesh, then export it as an obj.  It will take a little cleanup.  But for the most part it’s a good point cloud.  Not to messy.   The best part about this technique is you decide what the point cloud will look like depending on where you put the dots!  It’s all about you putting the dots in a good flow.