MIDI Emulation and CPU load

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NovaCoder
Posts: 74
Joined: Wed Sep 23, 2009 11:53 pm

MIDI Emulation and CPU load

Post by NovaCoder »

Hiya,

I'm playing with a platform port that only has about 10 MIPS of mighty CPU 'grunt' to play with :lol:

Although the game graphics are rendered (320x200) at full speed and the SFX is working fine the MIDI emulation is struggling badly.

Unless it's a silly bug in my port (always possible!), I assume it's because 10 MIPS is simply not enough to run the MIDI emulator and do everything else it needs to do.

Is there anything I can do at code-compile time to make the MIDI emulator run faster by lowering the quality?

Otherwise, is it possible for the ScummVM team to add a new 'low CPU usage' quick-and-dirty type MIDI emulator to ScummVM for us low power users?

I've tried both the DosBox and MAME emulators and MAME seems to need more CPU than DosBox.

Thanx

:roll:

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LogicDeLuxe
Posts: 406
Joined: Thu Nov 10, 2005 9:54 pm

Post by LogicDeLuxe »

There is more then one MIDI emulator.
Adlib is probably the worst for GM or MT-32 tracks, but I didn't notice any slowdowns with anything faster than about a Pentium 200.
Most systems have some native MIDI available, and ScummVM can translate MT-32 to GM. The load is usually unnoticeable this way.
The most demanding is probably the MT-32 emulator. Timidity can also be very demanding. On a recent system, both shouldn't be a problem anymore, though.

Rendering at 320x200 really is probably the less demanding about ScummVM. If this would overload the CPU, your system is probably not suitable for emulators at all. Using the advanced scalers on the other hand can increase the load a lot, which shouldn't be a problem on recent systems either.

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