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Environments
Environ Creation: How the DE Works
Following is a description of how to create content, and also methods for playing the content back.
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1. Create four synchronized video streams.
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2. Edit final piece.
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3. Playback in DE.
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1. Create four synchronized video streams.
Content for the DE is four synchronized video streams. The current maximum resolution is 720x480 pixels per image/video, the resolution of digital video found in most camcorders. The standard for DE content will be 640x480 or 720x480 pixels per video stream.
These video streams can be created in any way, with whatever tools people are comfortable with. Following are some of the techniques that we have been using to create content.
(NOTE: Content does not necessarily need to be four unique video streams. A piece could be created with the same video signal being projected on all four walls. Also a piece could simply be four still images, one projected on each wall.)
We have created a compound videocamera that records in all four directions at once. The DEcam is composed of four mini videocameras, each one recording the videostream to be played on one of the four DE projectors. This camera essentially creates a full DE environment instantly.
The challenge with building this camera was that it requires each camera to record with a 90 degree field of view. This type of lense proved difficult to find for standard digital camcorders. So, we have purchased four mini videocameras that come with 90 degree lenses. To record the video, we plug the four mini cameras into the VCR inputs on four miniDV digital camcorders. The end result is four miniDV video cassettes, one for each of the directions.
Utilizing four similar camcorders simplifies the recording process because it is possible to use one remote control to trigger all four camcorders to start, pause, and stop recording at once.
Because the lenses are actually wider than 90 degrees, it is generally necessary to capture the video to a computer and crop the streams. It is also necessary to capture the footage to perform any editing.
The DEcam is perfect for recording environments, performances, events.
Recording with the DEcam is a good way to generate source material for a piece as well, a piece might involve extensive manipulation and editing of DEcam footage.
(NOTE: The DEcam can be plugged directly into the four video projectors running the DimensionElevator for a realtime DE experience.)
Programs such as 3DStudioMax, Alias Wavefront, Cinema4D, Lightwave, Softimage, Bryce can be used to create content. The DE is an incredible display device for those interested in creating and experiencing virtual computer-generated environments.
Creating content with 3D modeling programs is very effective due to the simplicity of creating four perfectly synchronized, cropped, and color balanced video streams. The video files are easily created by placing four 90 degree cameras in a 3D scene and rendering out a video from each of the four cameras. Essentially, one creates a virtual DimensionElevator Camera. This virtual DEcam can either be stationary in a 3D environment and record the movement of objects in the scene, or the DEcam itself can be animated to move through a scene.
If you have 3DStudioMax Version 3, here is a file with a virtual DEcam in it. Simply import this file into the scene that you would like to bring into the DimensionElevator, and render out a video from each of its four cameras.
Download DECam 3ds max file.
Programs such as AfterEffects, Flash, Premier can be used to create four streams of video.
One technique is to create a workspace (Composition, Stage) that encompasess the full "width" of the DimensionElevator. If we assume full 640 wide by 480 tall pixel resolution, then four screens would be 640 * 4 = 2560 wide by 480 tall.
Create a 2560 x 480 stage, and create your piece on it. When the piece is done, render out four separate 640x480 videos from it.
Paintings, drawings, hand animation, photography, dance, poetry... all of these artforms can be interpreted and presented with the DimensionElevator. For some pieces it would not make sense, for others it would be a transformation, a new piece based on the old.
Performance art, such as dance, orchestral music and theater can be recorded with the DEcam. The camera can be taken into the middle of the performance to give the audience a new kind of experience.
Paintings and photography can be digitized with scanners or digital cameras. Once on the computer, these images can be arranged in a program like Photoshop and animated in a program like AfterEffects or Premier.
Alternatively, the DimensionElevator can provide a new sort of stage for theatre and dance. A play can be put on, or a video can be recorded inside the DimensionElevator, utilizing its chameleon walls to provide a transforming stage.
2. Edit final piece.
Depending on how you create your video streams, they may or may not need additional editing. Most content captured using the DEcam will need some editing. The main requirements are a fair amount of disk space and patience.
1. Time Sync
After capturing four separate streams, it will be necessary to make sure that all four streams are in sync. AfterEffects is perfect for this, but Premier also works.
In AfterEffects the four clips can be brought into a composition side by side. Choose some easily identifiable event to sync the streams. We have used two techniques for this: A. give the camera a jolt when you are recording, this is a recognizable element in all four streams. B. cover the cameras with a box, and remove the box at the beginning of the scene.
Once you have synched the streams, you might want to export them as four new video files, all with the same timecode, and toss the originals.
2. Cropping
Each DEcam camera records wider than 90 degrees, therefore it is necessary to zoom in on the image and choose the proper area on each so that all of the clips match up as well as possible at the seams.
Again, it can be useful to export the cropped clips as your new masters. Your masters should be 640x480 or 740x480 DV.
3. Editing
There are a number of techniques that could be employed to make the cuts and transitions that are the staple of editing video. One technique is to create a file that includes all four streams, all adjacent to each other. This file can then be edited like any other video file. When the editing is done, four separate videos can be extracted from the final quadstream video file.
3. Playback in DE.
Engineering synchronized playback of four audiovideo streams has been one of the biggest challenges of this project. There are many different desires for playback that must be balanced against how much time or how expensive it would be to realize them. Here are the three techniques that we will be using this summer.
To achieve seamless 720x480 playback on all four projectors, plus four stereo soundtracks, we will play content off of four miniDV cassettes on four miniDV camcorders. The output of each camcorder is connected to one projector and one stereo soundsystem. The miniDV digital format allows one to easily queue each tape to the proper frame. Using a remote control and four similar camcorders, all decks can go from pause to play in the same instant. We have tested this technique successfully using two SONY TRV-10's and two SONY TRV-20 camcorders.
dandelion collective visual wants to mix live in the DE, to create a flow through realities and environments. We want a format that will work with all of our existing mixing gear and software.
The solution is to create video files that include one video stream in each quadrant. We call this a QuadStream. Assuming a resolution of 640x480 for the file, then each of the four streams will now only have a resolution of 320x240. It is a tradeoff of image quality for versatility.
There are two ways to playback a quadstream file.
A. We mix entirely on one computer. The computer has four scan-converters conected to the monitor port. scan-converters are devices that transform a computer RGB monitor signal into a standard video signal. They can typically by used to do a 2x zoom. So, we aim each scan converter on a quadrant of the quadstream video, and send the output of each to a different projector.
B. The second option depends on having projectors that can zoom in on the signal they are recieving, such as the Hitachi CP-S860. We can then mix using standard video equipment. The quadstream signal is sent to all four projectors, and each projector zooms in on the proper quadrant.
As computer speeds increase it will be feasible to create a 1280 by 960 pixel quadstream video file so that each quadrant will have the 640x480 hires signal.
Another way to playback in the DE is to fake it.
A helpful way to test, preview, communicate, demonstrate a piece is to create a video of what it would look like in the DE. 3D programs can be used to create a video from the perspective of someone inside the DimensionElevator. At the most basic, the 3D scene only requires 4 screen/walls with the proper 16x12 foot size arranged to form a box. Then, each of the four videostreams of your piece can be mapped to the proper wall in the scene.
Simply building and viewing this model will help you to visualize your piece. It is also a good way to check to see that your streams are properly synched and that the edges line up.
To create a video of your environment, place a camera in the scene at the height of a person's eyes and possibly animate this camera to look around the room. We recommend a 140 degree field of view or greater for the camera to simulate a humans wide field of view. Render a video from this camera.
Download a 3dsmax ver3 DimensionElevator simulation file.
Thoughts
We hope that after reading this page you are excited about creating an environment for the DE. We cant wait to see what sorts of experiences people will create for each other. In the future we hope that many groups around the globe will set up DimensionElevator systems and trade/sell/share content with each other.
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