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 Post subject: How to find the *exact* frame rate for various consoles?
PostPosted: Mon Jun 09, 2014 8:43 pm 



Joined: 17 Sep 2007
Posts: 212
Anyone have a good resource for this? The only good discussion I've found so far is this thread on SDA but it's not complete and not everything seems properly sourced. I'd like to find a reference for every console by Nintendo, Sega, Sony, and MS. I'm also only particularly interested in NTSC systems.

Seems that pretty much every console deviates from the NTSC standard a little bit, either faster or slower. For that matter, how is the precise NTSC frame rate calculated? Is it "60 Hz / 1.001"?


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 Post subject: Re: How to find the *exact* frame rate for various consoles?
PostPosted: Mon Jun 09, 2014 8:56 pm 


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Joined: 08 Dec 2005
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Location: uoıʇɐɹnƃıɟuoɔ ɯǝʇsʎs
I want to think that this should allow deriving frame rates:
https://pineight.com/mw/index.php?title=Dot_clock_rates


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 Post subject: Re: How to find the *exact* frame rate for various consoles?
PostPosted: Mon Jun 09, 2014 9:10 pm 


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Joined: 16 Sep 2011
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Location: Germany
If you want to be scientific about it you could measure it with an oscilloscope.

The newest version of AmaRecTV also has the option to save frames as they come in, but I'm not sure how exact that works.


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 Post subject: Re: How to find the *exact* frame rate for various consoles?
PostPosted: Mon Jun 09, 2014 9:16 pm 



Joined: 17 Sep 2007
Posts: 212
blizzz wrote:
The newest version of AmaRecTV also has the option to save frames as they come in, but I'm not sure how exact that works.

I can already do that with VirtualDub, but the program itself has no way to determine what the source frame rate is. The user has to provide the frame rate value in order for the output file to be accurate. (The frame rate of the file can be changed in post if need be, without inserting, dropping, or otherwise reprocessing the actual frames of the video.) I assume AmaRec is similar, but I haven't tried that out in a while.

The best I've been able to do so far is calculate the frame rate by comparing the number of frames in the video stream to the length of the audio stream, but this isn't precise for short recordings, as the video and audio stream recordings tend not to start and stop at the exact same frame.


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 Post subject: Re: How to find the *exact* frame rate for various consoles?
PostPosted: Mon Jun 09, 2014 10:17 pm 


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Joined: 23 Sep 2013
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But frame rates differ across games...?

Digital Foundry (eurogamer.net) does this a lot for comparing different consoles and such. Like here. Guess you could ask what tools they are using.


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 Post subject: Re: How to find the *exact* frame rate for various consoles?
PostPosted: Mon Jun 09, 2014 10:38 pm 


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Joined: 16 Sep 2011
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He's asking about the hardware output rate, not how many frames are actually drawn by the software. The goal is to match a standard refresh rate (59.94Hz), but due to hardware limitations it is often not possible to exactly match that number. This problem isn't only limited to old consoles, though the deviation of old devices is higher than with modern hardware (in general).

For example the integrated graphics in Sandy and Ivy Bridge Intel CPUs (2nd and 3rd generation i-CPUs) couldn't output 23.976Hz. Instead they output at 23.972Hz which causes noticeable problems for video playback. Modern NVidia and AMD GPUs aren't perfect too, but a lot closer.

When you record old consoles at 59.94fps you will get frame drops or duplicates. So it is good to know their exact output frame rates.


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 Post subject: Re: How to find the *exact* frame rate for various consoles?
PostPosted: Mon Jun 09, 2014 10:49 pm 



Joined: 04 Jul 2013
Posts: 134
blizzz wrote:
When you record old consoles at 59.94fps you will get frame drops or duplicates. So it is good to know their exact output frame rates.


It's not just old consoles. If you have the 360 outputting 1080p, it's nowhere close to being a solid 59.94. It's screen tear city.


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 Post subject: Re: How to find the *exact* frame rate for various consoles?
PostPosted: Mon Jun 09, 2014 11:03 pm 


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Location: Germany
Screen tearing is a different problem. That happens when the game draws a frame while the frame buffer is being read. It can even happen when the console / PC outputs at a rock-solid 60.000 Hz.


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 Post subject: Re: How to find the *exact* frame rate for various consoles?
PostPosted: Mon Jun 09, 2014 11:41 pm 


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Joined: 23 Sep 2013
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Oh, refresh rates. Should have just called it that :)

Does anyone know what a NTSC PS1 outputs? By some accounts a NTSC PS2 outputs 59.82 Hz here, while modded PAL PS1s output 59.27 Hz for NTSC games. Should cause slight judder in theory, I'm already on the lookout for a NTSC unit to compare...


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 Post subject: Re: How to find the *exact* frame rate for various consoles?
PostPosted: Mon Jun 09, 2014 11:43 pm 


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Joined: 08 Dec 2005
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"Refresh rate" is almost a misnomer here. Frame rate is unambiguous terminology, or it should be - tearing is a signal that a system really isn't meeting its frame rate target. I don't think tearing even happens on most older systems. I suppose you could talk about internal and external frame rate, or maybe software and hardware frame rate, if you wanted to be more precise.


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 Post subject: Re: How to find the *exact* frame rate for various consoles?
PostPosted: Mon Jun 09, 2014 11:58 pm 


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Joined: 23 Sep 2013
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I guess hardware output rate as blizzz said would be probably the best term. "Refresh rate" usually pertains to how often a display updates, and "frame rate" how many frames the software outputs per second. The catch though is that, if I understand it correctly, a CRT can match its refresh rate to the slightly off hardware output rate of these consoles, which should always give better results than a less flexible LCD.

About tearing, it's rare on older systems indeed, but FWIW I've seen it recently on the NTSC-J version of Tenchu: Stealth Assassins on my modded PAL PS1.


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