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Topic: Reclocking 25fps videos

Reclock solves the problem where 25fps videos played at 60hz play 4% faster.

However, with madVR, SVP, Outer Lighting and Reclock, I have to make decisions as to which components I use as each have a processing cost. Reclock doesn't make it in my list of priorities. It costs on processing, and also costs on image quality.

And I'm wondering. SVP solves the fundamental problem that causes videos to play faster since you're generating inter-frames and altering the frame rate. Would it be possible for SVP to provide the effect of Reclock on 25fps videos without much extra processing and without any cost on image quality?

As a programmer, my guess is, probably yes.

  • MAG79
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Re: Reclocking 25fps videos

Mystery
problem where 25fps videos played at 60hz play 4% faster
I don't know such problem. Please give me a link to explanation of the problem.

each have a processing cost
You are mistaken. ReClock can do SVP work lighter. For example:
SVP without ReClock: 25 * (12:5) = 60. Only 1 of 5 source frames showed so in 1 second you see 5 source frames and 55 calculated.
SVP with ReClock 4% slowdown: 25 * (5:2) = 62.5 -slowdown-> 60. Only 1 of 2 source frames showed so in 1 second after slowdown you see 12 source frames and 48 calculated.

With ReClock video quality is better because it consists of more source frames and less calculated frames. Moreover SVP needs to calculate less new frames. GPU load is less. Moreover-2 after slowdown you get 24 fps source speed instead of 25 fps. It gives less calculation of motion vectors by 4% every second. CPU load is less by 4%. wink

In any time you can enable or disable ReClock and allow any speedup or slowdown (up to 10%) to get more video quality (and less CPU & GPU load).

http://www.svp-team.com/forum/misc.php?item=3170

Reclock... also costs on image quality
I can't confirm that. ReClock don't touch video frames. It make changes to audio track only.

So, what is bad with ReClock and 25 fps video?

Post's attachments

ReClock_Slowdown&Speedup.png, 14.94 kb, 492 x 539
ReClock_Slowdown&Speedup.png 14.94 kb, 662 downloads since 2014-04-24 

  • Thanks: 33

Re: Reclocking 25fps videos

Good to know. I'll experiment more with Reclock then. I thought there were more rendering glitches due to saturated processing but I can definitely be mistaken. I hadn't found clear information about the real pros and cons of Reclock.

  • MAG79
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Re: Reclocking 25fps videos

Mystery
I hadn't found clear information about the real pros and cons of Reclock
Read readme file from ReClock folder.

You didn't answer my question.
Please give me a link to explanation of the problem "where 25fps videos played at 60hz play 4% faster". Or tell more details what the problem?

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Re: Reclocking 25fps videos

I think he just  means the PAL speedup.

  • MAG79
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Re: Reclocking 25fps videos

SVPuser
PAL speedup
As for me it is not the problem wink

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Re: Reclocking 25fps videos

Yes I was referring to PAL speedup.
https://www.google.com.mx/search?q=pal+ … p;ie=UTF-8

I'm curious though. How does ReClock solve the problem of displaying 25fps on a 60fps screen, when not using SVP? (ReClock properties actually say display is 59.935 Hz (DDR))

Re: Reclocking 25fps videos

Mystery
"PAL speedup" issue is NOT about "25fps videos played at 60hz".
It's just about conversion NTSC's region DVDs into PAL's region ones - an ancient history now.

9 Reply by Mystery (edited by Mystery 26-04-2014 01:56:25)

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Re: Reclocking 25fps videos

I might be confusing things up.

But I'm pretty sure my 25fps videos are playing slightly faster without Reclock than with it.

If that's the case, how does 25fps gets rendered as 60hz?

Edit: OK, I verified by recording the playback with and without. It's exactly the same.

  • MAG79
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Re: Reclocking 25fps videos

Mystery
So. What about topic? It is closed?

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Re: Reclocking 25fps videos

One thing I'd like to understand. What effect does Reclock have on SVP?

Does it clock more precisely with the video card, and displays more exact source frames, instead of displaying calculated frames slightly before and slightly after real frames? Or does it change anything at all?

Re: Reclocking 25fps videos

Mystery
What effect does Reclock have on SVP?

it allows to sync SVP's output with the real screen refresh rate
e.g. 59.97 from SVP -- to 60.123 screen

the only purpose to use Reclock is if you really want ZERO dropped frames  roll
otherwise it's useless

  • Thanks: 33

Re: Reclocking 25fps videos

Chainik wrote:

the only purpose to use Reclock is if you really want ZERO dropped frames  roll
otherwise it's useless

Great, now that makes it clear.

The main reason for dropped frames is because of GPU/CPU saturation.

So in this case, Reclock's extra processing might instead increase dropped frames for some videos.

  • MAG79
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Re: Reclocking 25fps videos

GPU/CPU saturation

What? hmm

Enough to guess! Please read ReClock readme file.

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Re: Reclocking 25fps videos

According to Chainik, there are currently very little benefits to use SVP with Reclock.

GPU/CPU saturation causing dropped frames is a fact. For that reason, I have to disable Outer Lighting on my laptop screen, and disable madVR's JINC scaling on 1080p TV.

Reclock has to compute extra data, that's a fact. Whether it uses the CPU or GPU, or whether its computation difference can be noticed, is the only thing that is unclear.

Other than that, I think we're done with this thread.

16 Reply by SVPuser (edited by SVPuser 29-04-2014 09:29:03)

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Re: Reclocking 25fps videos

Mystery

For best performance you need Reclock. Also if you want to watch 24 fps  from 25 fps PAL videos.  And you're rigth Reclock can  change the playback speed.