[FFmpeg-devel] [GSoC] Motion Interpolation

[Davinder Singh]

On Thu, Aug 25, 2016 at 5:01 AM Andy Furniss <adf.lists at gmail.com> wrote:

>
>
> I am testing with a somewhat artificial sample in that it's a framerate
> de-interlace + scale down of a 1080i master, though it is "real" in the
> sense that I may want to repair similar files where people have produced
> a juddery mess by using yadif=0.
>

thanks for testing.

>
> It's very fast and my old (2010 Panasonic plasma) TV can't interpolate
> it without artifacting in a few places, it can interpolate a field rate
> version flawlessly and both mcfps and minterpolate do a lot better with
> a 50fps master version -> 100fps, though they are still not perfect.
>
> As well as being fast it has overlays of varying opacity and some
> repeating patterns just to make things even harder.
>
> Some observations while trying to get the best result - given the number
> of options only a small subset could be tested:
>
> aobmc vs ombc, vsbmc 0 or 1 = no real difference.
>

now our main focus will be on "better" motion estimation that removes
artifacts in fast motion, rather than little tweaks like these.


> Any me method other than epzs had far too many artifacts to be used.
>
> Raising search_param to 48 or 64 or 128 just causes new artifacts.
>

that hopefully could be fixed. working on it.


>
> Reducing mb_size causes new artifacts.
>

yes for higher resolution. for very smaller, it could be essential.


> bilat vs bidir - similar but bilat has some artifacts on a still shot
> near the end of the defaults sample uploaded. bidir sometimes has green
> near the top of the screen.
>

i see that green line in other samples too. investigating.


>
> There are of course many small artifacts, to be seen by slowmo/framestep
> for both minterpolate and mcfps. Viewing fullspeed mcfps artifacts less
> on the car when it touches the edges than minterpolate. Frame stepping
> shows mcfps doesn't blend/blur as much on really fast moving background
> as minterpolate does.
>
> Included in the link below (which is a tar to stop google drive making
> terrible low quality/fps previews) are the 25fps master file, mcfps
> interpolation to 50fps, minterpolate with default options and
> minterpolate with defaults + bidir.
>
>
> https://drive.google.com/file/d/0BxP5-S1t9VEEM2VrTzlVdGZURVk/view?usp=sharing


thanks :)

DSM_