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Topic: Force SVP to parse frames more often

Hello.

For those of you that know, anime has a peculiar issue in which the opening and ending animations run at 29.97 FPS, but the actual anime, on average, runs at 23.976 fps.

In other words, when properly ripped and encoded, anime episodes are VFR.

The issue is, SVP is too slow/dumb at detecting the frame-rate changes between the opening and the anime episode and between the anime episode with the ending.

Is there anyway to tell SVP to frame count more often? MediaInfo is incapable of knowing the corect FPS and MPC-HC will think the video is 29.97, but that's because of reasons I don't want to explain.

Can we force SVP to speed up frame parsing? It's an issue when we go from 29.97x2 to 59.94 but the FPS drops and SVP is still trying to interpolate things that clearly don't exist or when it does update it's interpolation frames, it's 100% wrong using values that make no sense.

I currently run in frame doubling mode so the 23.976 parts should be at 48.xxx........ .......

Yes, this is how anime works and no there is no issue with my video or video player, they're fine, it's SVP's problem.

2 Reply by Nintendo Maniac 64 (edited by Nintendo Maniac 64 30-11-2016 03:42:07)

Re: Force SVP to parse frames more often

icedtea676 wrote:

For those of you that know, anime has a peculiar issue in which the opening and ending animations run at 29.97 FPS, but the actual anime, on average, runs at 23.976 fps

I just want to say, every anime blu-ray I know of is 23.976fps for everything (since blu-ray doesn't even support variable refresh rates).

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Re: Force SVP to parse frames more often

icedtea676
It is good question. The speed of reaction on framerate changings.
SVP can detect framerate change but not quickly.
It is possible to implement instant reaction, but it is needed to parse current video file before playing to collect information about VFR segments.

Can you give a link to sample file with opening (and ending)?

Re: Force SVP to parse frames more often

yeah, looking through all the constants involved in the frame rate computations it could take ~11 secs to switch to the new fps value in this case

however IF it will react too fast we can end with excessive fps switching in a real VFR videos

5 Reply by icedtea676 (edited by icedtea676 30-11-2016 13:04:41)

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Re: Force SVP to parse frames more often

Nintendo, I personally haven't worked with a BD anime yet, but will soon.

This is specific to DVD's which are quite difficult to work with and as far as I'm aware, most anime do actually have 29.97 opening/endings, but I can confirm that when I get some BD anime to rip.

A sample of the opening with a bit of the anime - It should be fine - https://drive.google.com/file/d/0By9ra_ … sp=sharing

If the excessive switching causes an issue with those true VFR videos, maybe it could be an option (Anime - VFR), so it'll use specific settings instead.

An issue I've observed is that when SVP detects a framerate change, it attempts to adjust the values, but it'll get something crazy like 19.11 fps, which... well that's impossible :3. Other times, if I pause and force a seek in the video to get SVP to reinitiate, it'll find a value really close like 24.03fps.

Or something like telling SVP to only look at the video and determine if it's 23.976 or 29.970, since those are the only two values we work with anyway.

Thank you for trying to look into the situation. VFR videos have always bugged me with SVP because it's so uncertain in capturing the correct frame-rate, always a hassle to watch DVD only anime sad.

Edit: I'll just add that SVP is able to correctly find the fps value of the anime if I start up MPC-HC with SVP disabled/off, skip the opening, start the anime and then enable/start SVP, it finds that it's 23.976 no problem, but sometimes it also gets confused too =/

Re: Force SVP to parse frames more often

additional problem is SVP doesn't have any "direct interface" to read true fps value
SVP can only use the number reported by ffdshow filter, which is also an averaged value over some unknown time

7 Reply by icedtea676 (edited by icedtea676 30-11-2016 15:04:53)

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Re: Force SVP to parse frames more often

Ah okay, I don't really know how SVP works, this could be an ffdshow issue alongside with how SVP needs the data or something.

Speaking of which though, I decided to take a look at FFDshow raw video decoder while I'm watching an episode, it does at least notice the difference, Opening is read as a straight Movie FPS : 29.970 and the second the anime section starts, it does Movie FPS : 23.8xx-24.0xxx, the numbers change super fast. Maybe that could be an issue?

I'll check if FFDshow raw acts the same way with a sample of only the anime section encoded properly.

Edit: I took a sample of the raw DVD file and used the same encoding settings I used as normal for the anime sections, FFDshow raw does indeed read it as a stable 23.976 fps. Maybe because the anime is VFR is has a harder time "understanding" that it's still supposed to be 23.976? No idea, but in playback, there is no real problem, I can confirm that much as well.

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Re: Force SVP to parse frames more often

icedtea676
I've download your video. Thank you.

In my case SVP changed smooth coefficient from 2x to 2,5x in 7 seconds after end of opening.

mkv2vfr output:

# timecode format v1
Assume 23.976
0,790,29.9701
791,791,20.4082
792,3714,23.9759

So, from frame 0 to frame 790 video has 29,9701 fps and from frame 792 to frame 3714 video has 23.9759 fps.
And we can calculate the moment of framerate switching from one fps to another.
It is 791 / 29.9701 = 26,4 sec

P.S. I used mkv2vfr from Haali Matroska Splitter bundle.

Re: Force SVP to parse frames more often

it's about 5 secs reaction time to switch from 30 to 24 fps with the sample given
well, it's not too much I think hmm

10 Reply by icedtea676 (edited by icedtea676 30-11-2016 16:54:21)

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Re: Force SVP to parse frames more often

Do you know if maybe something changed between SVP3 and SVP4, because the changes on my end aren't smooth regarding this.

Edit: I decided to fully re-install SVP 3.17a and then use the updated SVPflow plugins... the issue seems to have been fixed and the change works......

Something could have been wrong on my end then. Thanks for taking a look into it for me.

Sorry for using up your time on this ! smile

Re: Force SVP to parse frames more often

ahhh, we were taking about SVP 3... big_smile
or what? hmm

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Re: Force SVP to parse frames more often

Yeah I use SVP 3.

There must have been an issue with my configuration or something, because there seems to be no problem now. The change in FPS happens in like 2-3 seconds and it gets accurate to the frame-rate of the video....


Sooo, no idea what happened :3.