Regional dependencies on ROMs across different emulators

TimZett

I searched and couldn't find the right answers for this, so let me put it down here.

I stay in a PAL region, hence having a PAL TV running at 60 Hz with Retropie.
Now I noticed the same as many other users, that depending on the region for which a particular ROM has been made, either the gaming speed is too fast or too slow, or playback is choppy or with wrong aspect ratio, or the game doesn't even start.

What I perceive is that the "default region" of one emulator differs from another. For instance, on the Vice emulator, it seems to me that "European" ROMs play at the right speed, while others are too fast.
On the other hand, with the Atari 7800 emulator, at least on my system the US ROM versions are the right ones to be chosen. Not only that the European ones play too slow or stuttery, some of them simply don't run.

Now my questions are:

Am I right saying that the "default region" varies among the different emulators and if so, is that documented somewhere?
Can the regional behavior be customized, either on a per-emulator basis, per ROM or even in general for Retropie respectively Emulation Station?

EDIT (maybe you find I did something wrong here):
My default display setting in all Emulators I set to CEA-4.
In the /boot/config.txt I set the following:
hdmi_group=1
hdmi_mode=4

TimZett

An additional thought:
In (PAL) Europe where I am, 1280x720 is a valid resolution. Hence I chose this (CEA-4) as default for Retropie and for all my emulators as well.
Because of that, still I'm wondering why some emulators deform the aspect ratio on European ROMs?
Is it maybe that I have to choose the native resolution the original console had? Like for the Atari 7800, 320×288 pixels for PAL?

But then again, still the other issues with from refresh rate, too slow or too fast gameplay etc.
I'm really wondering what's going on here.

mitu

@TimZett said in Regional dependencies on ROMs across different emulators:

Am I right saying that the "default region" varies among the different emulators and if so, is that documented somewhere?

Depends on the emulator, so best to look on their doc page. Many Libretro based emulator have some sort of regional setting where applicable - mostly on automatic. You should find them in the Core's settings (the Options menu in the RGUI). For instance:
Nes:

Genesis/Megadrive:

https://docs.libretro.com/library/genesis_plus_gx/#core-options

Sony PS1

https://docs.libretro.com/library/pcsx_rearmed/#core-options

Can the regional behavior be customized, either on a per-emulator basis, per ROM or even in general for Retropie respectively Emulation Station?

For Libretro based emulators, it's enough to change it in the Options menu and it will be applied to the emulator as a whole, but you can also save it per-game.

As you can see, I don't use many non-Libretro based emulators, but it's entirely up to the emulator on how it implements it (defaults and overrides).

There's no general setting (in Emulationstation) that influences regional settings in emulators. RetroPie might configure an emulator with different options and make the options available in the Runcommand launch menu - for instance an emulator can accept via the command line parameter which region emulates so you can start it different options. If it's done, then you can also choose per-game or per-system which emulator is used.

EDIT (maybe you find I did something wrong here):
My default display setting in all Emulators I set to CEA-4.
In the /boot/config.txt I set the following:
hdmi_group=1
hdmi_mode=4

No, that has nothing to do with it.

In (PAL) Europe where I am, 1280x720 is a valid resolution. Hence I chose this (CEA-4) as default for Retropie and for all my emulators as well.

That's what is called 720p (HD) resolution and it's not PAL specific. In fact the whole PAL vs NTSC vs SECAM only exists for the analogue television era, ever since LCD/OLED/Plasme, that difference doesn't exist anymore.

Because of that, still I'm wondering why some emulators deform the aspect ratio on European ROMs?

Can you give an example - emulator and ROM ? Could be because of different regional settings in the emulator.

Is it maybe that I have to choose the native resolution the original console had? Like for the Atari 7800, 320×288 pixels for PAL?

I wouldn't worry to much about changing the resolution of your TV to the one of the originating console or system - you have a 16:9 flat screen, while most of the retro systems had 4:3/5:4 output resolutions, your TV is based on pixels, the original TVs was not. The emulator should be able to scale it to your native TV screen's resolution.

EDIT: What I've other people recommend - and it sort of makes sense - is to try and run the NTSC version of a ROM when possible. NTSC ran at almost 60hz, similar to the modern displays.

TimZett

@mitu said in Regional dependencies on ROMs across different emulators:

The emulator should be able to scale it to your native TV screen's resolution.
EDIT: What I've other people recommend - and it sort of makes sense - is to try and run the NTSC version of a ROM when possible. NTSC ran at almost 60hz, similar to the modern displays.

Bingo - that's exactly what I just did before I'm reading this :-)
Set boot config to CEA-4, removed default emulator video choice from on-game startup menu and sorted out my ROMs so now it's all USA (NTSC) versions.
Now it's all perfect.
As always: Thanks buddy for your good explanation and clarification.