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[loocas]

Hi there guys,

I'd like to ask a few questions about a shoot I'm about to supervise, that'll require us to precisely track the camera motion.

The requirements of the shoot call for a supervised tracking via a witness camera setup, I'm about to build and deploy on set.

The problem is, I'll need to track the real camera as it moves in the scene using ONLY these witness cams. I'll do this similarly to what The Mill used in their City Harvest spot.

I'll build the tracking "tripod" etc... but, I only have experience with this kind of a setup in a regular motion-capture environment using on-line software, such as the Arena, but, I won't have the mo-cap setup available for this shoot.

I'll use a number of regular Playstation 3 Eye Cams (I'm thinking 4-6 cams) to setup so that they can clearly see the entire set. I'll sync-record everything using the iPi capture software, but then I'll need to track and solve everything using SynthEyes. My questions are:

1) I'll need to first determine where the cameras are. This is usually done in a regular mo-cap scenario by randomly waving and moving around a special "wand" with tracking markers, the software then calibrates the setup and solves the cameras' positions automatically.

2) Determine the ground plane. Again, usually this is done by tracking a rigid "tripod" that I can easily take and place on the ground. This, again, happens pretty much automatically in the regular mo-cap setup. I'm sure it can be done in SynthEyes, but I've never done that in SE before.

3) Lastly, when all this is done, I'll, obviously, need to track the real camera which will have the marker "tripod" attached to it. I imagine when I load up the solved scene in SE and load up the six source videos in there, I'll be able to precisely solve the "tripod's" position in space/time.

This is all I need. I know it can be "easily" done in a regular on-line mo-cap studio, but I'll be limited to offline imagery provided via PS3 EyeCams (6 I think will be enough) at 60fps or even 120fps (though the resolution will be 640x480 or even 320x240 respectively)

Can anyone tell me this is possible to be done with SynthEyes?

Thank you very much in advance, best...

[borgus]

Hi Loocas,

are you sure that you wanna do that with playstation cameras? I've
played around a abit with ipi studio/ ipi recorder and wasn't able to get a good sync of more then three cameras. The other questions is how do you wanna use the produced footage to track in syntheyes due to heavy compression and the way the camera images are layed out in the final "image stream". You'd have to edit the recorder output and split it off
in seperate sequences... Did you test the basic workflow before?

Seb

[loocas]

[borgus]

hmm... ok. I've just checked the latest ipi recorder and the sync is no
problem anymore... that's good to know

you definitely need more points to calculate the camera positions in syntheyes, so you
need something like the porcupine-ball (there's an image of it in the manual).
As far as I know Syntheyes mocap solution only works with three cameras,
but I might be wrong!

[loocas]