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Assignment #1: Introduction to Chroma-keying

Due: Thurdsay February 5, 2004 NOON

Goals | Part 1 | Part 2 | Part 3 | Submission Info

New for this 2004: (a) 2 videos required (b) A write-up required

Goals:

1. Undertake the entire pipeline from shooting video to digitizing video to maniplulating & processing video to rendering new video to encoding and saving a file for submission.
2. Learn the basics of Adobe Premiere and After Effects so you can use both for simple editing and so you know how to apply the built-in features, should you need them.
   OR learn the basics of Final Cut Pro / Shake for Mac Users!.
3. Spot the challenging aspects of compositing: segmentation, reflections, shadows, lighting, and real/virtual camera alignment.
4. Determine how to control the environment that best supports chroma-keying.

NOTE: This is a learning exercise, so it only affects your grade if you don't do it. Make the footage look as good as possible, but it won't be pretty for reasons we'll talk about in class.

NOTE For Mac Users: You can do this assignment using Final Cut Pro and Shake.

Part 1: DV capture

Bring a photo-copied version of your ID and a printed version of the sign-out form to checkout a camera from the TA (during their office hours!).

Camera Checkout Order:

Film a subject in front of a solid-color background. It doesn't have to be fancy, just something that moves around for about 15sec. One good area to film in the chroma-key area in the Digital Media Lab (CoCB 104a) or in any space that you can convert into a controlled space with fixed color background and controlled lighting. In DML (CoCB 104a) we have a roll of blue paper hanging from the wall and a roll of green paper on the floor.  Please do not tear any of the papers, and be careful to use them.  Both rolls can be manually opened.  Please do not step on these with soiled shoes etc. either, Remember you will need these for your final projects.

Consider turning _off_ various auto-options of the camera (things like auto-focus and auto-gain will cause your solid color to change its appearance throughout the sequence). The footage is now a DV file sitting on the miniDV tape, and needs to be pulled onto a hard-disk as described in class.

Part 2: Premiere (These are for PC folks, MAC folks, feel free to use MAC OSX software as needed)

Composite the movie onto an image or movie of your choosing. If you are eager to learn this stage before getting access to a camera, some sample sequences are in

/net/dvfx/DVFX/2004/sampleData/*.avi.

Rather than ftp, we recommend you set up a symbolic link from your UNIX home, so you can put/get files through samba:

unix% ln -s /net/dvfx/DVFX DVFX (In Unix)

Guiding Steps

1. Run Premiere
2. Agree to the default project
3. File->Import->file your favorite of the movies on DVFX
4. Drag its icon from the project to the timeline's Video2 layer
5. Import an image or movie you found/generated/stole
6. Drag it to the Video1 layer.
7. In the time-line, play with the time-slider, moving files around in time, etc.
8. Right-click the green-screen footage and pick Video->transparency.
9. Try the different keying types. Especially play with the sliders for Chroma keying and Difference Matting (notice, this asks you for a matte-file, which you can extract from the sample movie by rendering out a frame).
10. Play with the Sample window and its controls (try holding down space-bar and Alt). Notice the 4 handles in the corners of the sample window.
11. When done, adjust the blue Workspace bar at the top of the Timeline window to select the part you want to render.
12. With the Timeline window active (won't work otherwise), File->Export->Movie.
13. Check all your settings! You want to export an .avi, and you want the codec to be none/DVRaptor/other at high quality. To stay under 200MB in final size, try rendering a shorter movie, or using a different output resolution.
    Extra: Add a title screen and a transition effect, and maybe some audio.

Part 3: After Effects (These are for PC folks, MAC folks, feel free to use MAC OSX software as needed)

1. Same as above, but very slightly different interface, and lots of other features to play with.
2. Run After Effects
3. Effect->Keying->Color Key, and play from there Also try Transfer Mode->Difference and others
4. It's not blue, but it's still just above the time-line.
5. Composition->Add to Render Queue.
6. Window->Render Queue, and adjust the settings to suit.
   Extra: make a split screen using masks and/or Transformation of the layer
    

Submitting results:

Videos:

Report (Write-up):

In addition to the above submitted video, create a webpage on your class swiki pages (see template) showing at least 1 image from both of your video, marked in some drawing program and a description of was the problem in the marked region and how it could be solved.
 

This assignment should not take long, even if you have never used these tools before. You're getting so much time to complete it because you're working individually, so not everyone can check out a camera at the same time... i.e. don't wait until the last minute.

Grading Breakdown:

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Last updated: January 21, 2004 04:19:09 PM.