Max_Rebo said:
I hope that makes sense, if not I'll try to explain tomorrow.
I definitely understand what you are saying!
Max_Rebo said:
I've been thinking about it and I'm still not sure if a median filter would be better, in your example you made the assumption that only a third of pixels duffer from noise and that no one pixel suffers noise in two captures, which is a highly idealised situation.
I think the median method would be a good way avoiding bursts of static or dropouts that may not be reproduceable so only effect one capture but I can't see how it would help with the smaller random variations present in all analouge captures, when dealing with random variations taking the mean of the multiple values is surely the better way.
You are correct. But it will depend on what type of noise you have. The random variations you are used to with VHS are much smaller with LD. The biggest problem with LD is the noise introduced by such things as laser rot and dot crawl. These are not random variations that affect the entire frame equally, but rather isolated incidents that do not always occurr in the same place on every capture. I guess it all depends on the type of noise you have, and hopefully Arnie.d will try both!
Max_Rebo said:
will the scenechange parameter allow the middle capture to be excluded from the average? as this would not be useful for it's original purpose and the differences are measured relative to the middle capture, so if the middle capture had a significant problem then the other two would be excluded and the problem would remain.
You are correct. I didn't think of this situation. I could code up something that would replace the scenechange parameter to still average the 2 good frames.
Max_Rebo said:
what does it really mean by 'average pixel change'? is it a percentage? if 5-30 is appropriate for a change in scene isn't 25 too great a difference for supposedly identical frames I wouldn't expect 2 captures of the same frame to be different by more that 1-2%
The scenechange parameter is the maximum allowable average pixel difference in luma from one frame to the next. 25 may not be the best value especially if the captures are relatively noise free.
Orinoco_Womble said:
g-force said:
Also, there may be some benefit to throwing a mocomped-denoised source into the mix as well.Sorry, didn't understand that bit at all. Umm, whats a mocomped-denoiser?
That was Moth3r's quote, not mine! A mocomped-denoiser is one that motion compensates objects in previous and next frames to their positions in the current frame and does some sort of filtering (median, average, fft etc.) on those frames.
-G