Converting Film to Video
If you’re transferring film to video, you’ve already made a significant investment in your content. Preserve your investment by making a few tweaks designed to give you a lower bit rate with less work.
Follow these steps in order. If you mix up the sequence, you may accidentally undo work you’ve just done.
- First, make any adjustments to the frame rate that may be necessary. If you used telecine to transfer your footage, use reverse telecine (3:2 pulldown removal) to get your footage back to 24 frames per second. Telecined footage has a higher frame rate and so will take more bits to compress. Removing pulldown also helps to preserve the look of the original film.
- After correcting the video’s cadence, remove unwanted dust and scratch artifacts. Be sure to perform dust and scratch removal before scaling the video. Changing the resolution of the video will defocus the dust and scratches, making them much harder to eliminate.
Figure 1: Focused dust, before scaling (L), compared to unfocused dust after scaling (R).
- Sometimes, the telecine process introduces a bobbing motion effect similar to that produced by a handheld camera. This “gate weave” should be removed using an image stabilization filter (like SmoothCam in Final Cut) after dust removal, but before scaling.
- If the noise is stationary, try applying a blur filter in the horizontal axis to reduce its visibility. If the noise changes from one frame to the next, try a film grain removal filter. Even if the noise is not film grain, it may be similar enough to be acted on by the filter. If you have the latest version of Final Cut Studio, Color has a Grain Reduction filter that will help by averaging adjacent pixels in the frame. Edge Retention can be used to preserve important areas of detail in the shot. See p. 254 of the Color User Manual for more detail.
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Posted: 2008-08-21