@castellandw,
Now I follow. (That paper is the first hit when Googling "motion compensation".) What I posted on that forum amounts to little more than Fizick said above; it was mainly to elicit a more detailed response from James Insell. Now the thread is gone, let's leave things be.
@Mug Funky,
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actually, a "delta" option similar to that of mvtools would be great for denoising.
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It's trickier in this instance because each motion estimate depends on the motion estimate for the previous frame... I could create something that mimicked SelectEven.FindMotion, but I think the found motion vector quality would degrade. On the other hand, this is perfectly legit:
#source = ...
motion = findmotion(source, useassembly = true )
source
compensate(motion)
compensate(motion)
I.e., get the motion vectors once, move blocks to compensate original frame n-1 -> n, then move blocks to compensate compensated frame n-1 -> n. So we have:
original frame n-2 -> compensated frame n-1 -> doubly-compensated frame n
Will that do? I can definitely implement something else, given specifics.
By the way, using that ^^ script will make the blocking/inaccuracy worse for obvious reasons. There are a range of things which can be done to improve the motion vector quality, but I think I'm going to try and get an application out first... it makes it easier for us to check whether a particular change is actually helping. For similar reasons, I would like to have better quality motion vectors before trying mesh warping.
From
Phase Correlated Motion Estimation:
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Phase-correlation ME is very computationally efficient and it produces much smoother motion field with low entropy than the BM method does. Phase-correlation works better than the BM does in the cases of large scale translational motion, while BM is more suitable for predicting regular and small scale motion and multiple-object movement.
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(Bear in mind that that compares phase correlation against full/logarithmic search block matching... actually I think it's some student report, so doesn't carry that much weight in itself -- but the conclusion looks very sensible to me.)