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View Full Version : Exhibit A - Cropping, but keeping cropped area "still" despite camera movements


BlueToast
29th March 2011, 02:58
http://www.youtube.com/watch?v=CD2LRROpph0
Go to 1:17

http://i.imgur.com/XCgZL.gif
This picture -- please ignore the captions and any hilarity.

I do not know what it is called when this is done. In the video, the camera is moving. In the image, that particular location of the frames in the video is made to be "still", and for each frame whatever they used or did would adjust each frame to make it look like the camera wasn't moving either (or whatever).

Know what I mean?

So this is what I am curious about: how do people do this? Is there a specific name to this kind of doing?

I have also seen people record something with a camera by standing in one location, but moving the camera around a lot while stationary; I would see the resulting video as a big field having a black background, and the actual recording in the center of the field dynamically adjusting itself as the video plays to maintain sync with uprightness (of course, the camera does not have anything for this, but someone made it so despite camera rotations the thing being recorded always appeared upright).

poisondeathray
29th March 2011, 04:52
Shot indoors on green screen , with the background is composted in . The car isn't really moving. You can see residual green spill and fringe probably from poorly controlled lighting

BlueToast
29th March 2011, 15:01
Ah, well, I see what you mean. But do you understand what I am trying to ask though?

A camera with lots of movement, but stablized via software. What is this called (if it has a name) and how is it done?

Ghitulescu
29th March 2011, 15:21
"This video is not available in your country. Learn more." I wonder why.

aegisofrime
29th March 2011, 15:26
It's called anti-shake, or motion stabilization. For VirtualDub, there's Deshaker. Not sure what there is for Avisynth though.

poisondeathray
29th March 2011, 17:14
Ah, well, I see what you mean. But do you understand what I am trying to ask though?

A camera with lots of movement, but stablized via software. What is this called (if it has a name) and how is it done?

I don't understand what you're trying to ask ?

There is very little camera movement in that shot ~ 1:17 . The actual camera move is a slight pan. The background is percieved "moving" because it's a composited shot (there is a video playing in the background where the green screen was keyed out)

The foreground is not moving at all (the car, the people in the car). It's shot in a studio.

BlueToast
29th March 2011, 19:13
I don't understand what you're trying to ask ?

There is very little camera movement in that shot ~ 1:17 . The actual camera move is a slight pan. The background is percieved "moving" because it's a composited shot (there is a video playing in the background where the green screen was keyed out)

The foreground is not moving at all (the car, the people in the car). It's shot in a studio.See post #3.

BlueToast
6th June 2011, 07:42
Like this:

http://wimp.com/earthrotating/

Filker
12th June 2011, 12:20
Nice video.

I think what you're looking for is usually called matchmoving, camera tracking, it's also called 3D tracking although it's tracking a 2D image as this method is widely used to extrapolate a 3D space to insert 3D objects and "repaint" movies with 3D layers.

If you got between 5 and 10k to spare you can pick one of the following commercial software for matchmoving:
PFTrack, Syntheyes, Boujou, Matchmover...

Freeware implementation: Voodoo Camera Tracker
http://www.digilab.uni-hannover.de/docs/manual.html#overview

Deshakers already implement the 2D motion tracking used in basic matchmoving and can probably be tweaked to create the video you linked to.

Here's an implementation in avisynth:
http://sourceforge.net/projects/avisynthtrackin/

http://www.youtube.com/watch?v=SQ-JtJs7US0