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CamTrig DAVID3

Discussions about latest DAVID developments, beta versions...

CamTrig DAVID3

Postby MagWeb » Fri Jul 08, 2011 10:46 am


just loaded a new CamTrig version to the WiKi:
This java app is meant to synchronize any cam you can somehow trigger using a micro controller (means via cable- or IR remote) and a projector, set up as a second monitor that extends the Windows desktop. ... ds#camtrig

Arduino recieves a "T" to push the trigger and a "R" to release it (as it were in previous versions of this app)
This one should be compatible to DAVID 3 running in SL at cl+ps mode.

You can:
- dim the projector by R G B channels,
- set FREQUencies and SHIFTS values ( which have to be the same as set in DAVID3);
- use vertical or horizontal shifts: HORIZ - toggle;
- projector resolution and position should be detected automatically;
- setting SPEED, you increase/decrease the pattern holding time;
- GLOBAL_OFFSET adds a pause before the pattern start (to let the Arduino do its job)
- TIME_OFFSET adds a shift between the moment of projections start and of triggering,

Each series starts with a white projection (to use as texture or to calibrate the cam).
To cam calibrate DAVID3 simply load the image showing the corner using the image grabber.

To calibrate the projector:
Grab two series:
Horizontal stripes first and vertical ones afterwards projected on the corner.
Now load both series at once (without the white images!) by multi-selection using the image grabber within DAVID3 and hit the projector calibration button. If DAVID is set at the same values as CamTrig was it should be successful.
For following object scans horizontal stripes should be enough.

Note: Close this app via the task-bar otherwise java keeps running - Don´t know what I´m doing wrong here.

ATM I have no hardware to test that out (cann´t find my casio any more since my daughter had it :twisted: ), so I would be glad if it works for you

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Joined: Wed Jul 18, 2007 8:48 pm

Re: CamTrig DAVID3

Postby maxem » Fri Jul 08, 2011 7:21 pm

Amazing! very busy but will test as soon as i can, THANKS!
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Joined: Mon Oct 19, 2009 5:56 pm
Location: USA

Re: CamTrig DAVID3

Postby jhfelectric » Sun Sep 22, 2013 2:42 pm

Hello Gunter,
I am very interested in your RGB channels-setup. I do not understand what kind of processing you can use to “extract the RGB channels”. Basically, 3 projectors would project the same patterns in Red, Blue and Green – each resulting frame would then have stripes in a different color. How do you reconstruct a Black stripe from a Blue stripe on a color image ? My guess is that you turn any Blue into Black by swapping colors again on the result frame, and then use this frame in David, without the color information (as in a monochrome frame). Then, to apply texture, you take a last shot with true colors. Am I right ?
Thanks for any help and advice.
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Joined: Mon Sep 16, 2013 2:56 am

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