Darren New wrote:
> Kevin Wampler wrote:
>> The technique used by Photosynth is called "structure from motion".
> 
> Thanks, but I was thinking more of a technique where you already know 
> which points on the image are also on other images, rather than where 
> you have to deduce them.  For example, I could take a few images of a 
> simple cubistic object, the point out "this point is the top left corner 
> of the doorway in this photo, and that point is the top left corner of 
> the doorway in that photo".  I saw an article long ago about that but 
> didn't learn the math.

I've still heard what you're referring to called structure from motion, 
but I believe the term you're looking for would more accurately be 
called "bundle adjustment".  The reason I didn't mention that first is 
that in practice you often need other elements to the algorithm in order 
to avoid the local minima which the nonlinear least squares optimization 
used by bundle adjustment is prone to.

>> get too excited, there's a reason why you haven't seen any major demos 
>> of getting 3D models from Photosynth yet.
> 
> I just thought it was cool. :-)  I like easy ways to get models.

It is cool.  And I'm relatively sure we'll be seeing some really neat 
stuff in this area within the near- to mid-term future.

Post a reply to this message