Twixtor is a complete slow-motion-effects plug-in for all professional editing systems and widely considered the benchmark against which to measure other effects. Using key frames, it offers total control of the speed of your clip on a frame-by-frame basis. It also has the most advanced interpolation algorithms in the industry, which allows fewer artifacts and other problems that can result from applying slow motion. Twixtor is easily the best option for video professionals.
revisionfx.com/products/twixtor/
For those who work with the Audio Video Interleave (AVI) codec on a regular basis, such as web video producers, MotionPerfect is an ideal tool. Designed from the ground up to work specifically with AVI, MotionPerfect can be used to turn choppy video into smooth slow motion. MotionPerfect's interpolation algorithms are designed specifically to replace missing frames in AVI footage and add new frames to create motion effects, and is perfect for online video applications.
goodervideo.com/products/MP.html
For the hobbyist who may not own an advanced editing system, Slow Motion Smoother is the perfect fix for the slow motion in consumer editing software, such as iMovie. Slow Motion Smoother is designed specifically to take slow motion generated by these programs, add frames, clean up artifacts, and output a more professional clip. It's the perfect solution for film students, video artists on a budget and hobbyists experimenting with different effects.
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