Apple MA434Z/A User Manual - Page 198

When the deInterlacing parameter of a FileIn node is set to either odd or even, Shake separates the two fields within each frame, placing field 1 at frame 1, and field 2 at frame 1.5. This effectively doubles the number of frames processed within your script, but keeps them within the same duration of the Time Bar. Turning on deInterlacing for each FileIn node ensures that all animation, transforms, and filters are properly handled by Shake's field rendering. How to Determine Field Dominance If you're not sure of the field dominance of your media, scrub through the first few frames in the Time Bar until you find a range of frames with an obvious interlacing artifact (generally found in frames with a fast-moving subject). Choose a field rendering setting in the Parameters tab, set the frame Inc setting in the Time Bar to 0.5, and then step through that group of frames to see if the motion looks correct. If you perceive any stuttering, that's an immediate sign that the field dominance you selected is incorrect (which results in every two fields playing backwards) and should be reversed. If the motion of the clip is subtle and you're still not sure, it may be a good idea to render a test clip that you can output to an interlaced broadcast video monitor. Any motion artifacts should be immediately visible. Setting the reTiming Parameters of Each FileIn Node After you've set a FileIn node's deInterlace parameter to the appropriate field dominance, an optional step is to open that FileIn node's Timing tab and set the reTiming parameters. Preserving Interlacing This step is not strictly necessary if you're not removing, reversing, or adding interlacing to the source media, but will improve the processing of clips in Shake when you're making transformations to interlaced footage-even when you're preserving the original interlacing for video output. To preserve the interlacing from the original source media: 1 Click the right side of the FileIn node to load its parameters into the Parameters tab. 2 Open the Timing tab. 3 Set the reTiming parameter to Convert. Additional parameters appear below. 4 Set the InputFrameRate to match the format of the original interlaced video media (NTSC or PAL). 5 Open the InputFrameRate subtree, and turn on InputFrameInterlaced. The InputFrameDominance defaults to the same setting as the deInterlacing parameter in the Source tab. 198 Chapter 6 Importing Video and Anamorphic Film