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Amiga computer related discussion => Amiga Software Issues and Discussion => Topic started by: cockney_dave on May 15, 2003, 08:22:41 PM

Title: mp3 encoding without an FPU
Post by: cockney_dave on May 15, 2003, 08:22:41 PM

Does anyone know of an mp3 encoder for Amiga that doesn't need an FPU?
I have a fast 060 but it doesn't have an FPU and all the encoders I've
come across seem to require one.

Thanks all

Title: Re: mp3 encoding without an FPU
Post by: Karlos on May 15, 2003, 08:25:32 PM

I dunno really.

You could always get some existing source and compile it yourself to use the amiga math libraries.
Pity, a lot of 68060 stuff assumes FPU and with good reason - the FPU in the 68060 is damn fast compared to any other 680x0. So much so that it even gets used for some integer calcs too (especially 64-bit mult/div emulation).

Title: Re: mp3 encoding without an FPU
Post by: olegil on May 15, 2003, 09:13:26 PM

Quote

Karlos wrote:
I dunno really.

You could always get some existing source and compile it yourself to use the amiga math libraries.
Pity, a lot of 68060 stuff assumes FPU and with good reason - the FPU in the 68060 is damn fast compared to any other 680x0. So much so that it even gets used for some integer calcs too (especially 64-bit mult/div emulation).

Not too odd, considering the 68060 doesn't have hardware mul64/div64, unlike the 020-040 CPU's. Running those via 68060.library really doesn't cut the mustard. :-)

Title: Re: mp3 encoding without an FPU
Post by: Karlos on May 15, 2003, 09:18:35 PM

Quote

olegil wrote:
Not too odd, considering the 68060 doesn't have hardware mul64/div64, unlike the 020-040 CPU's. Running those via 68060.library really doesn't cut the mustard. :-)

What I meant was it uses fpu over doing the same job in integer emulation code beacuse it's so fast at floating point...

Title: Re: mp3 encoding without an FPU
Post by: olegil on May 15, 2003, 09:20:21 PM

Yeah, but even if it sucked at floating point it would still make sense running those two instructions in the FPU because the software exception handling sucks even MORE :-)


Edit: Or you could *cough* do it the old way with more 32 bit instructions. But I mean, that would mean engaging brain functions, right?

Title: Re: mp3 encoding without an FPU
Post by: Varthall on May 15, 2003, 10:08:05 PM

I have on one of my cds a copy of Bladeenc that runs on my 030 without fpu. Well, of course it's slow as hell, needing something like 48 hours to encode a single tune. It used to be downloadable from Aminet, but it has been removed because of legal reasons (a txt file is still there to remind this). Try to download it from here:

www.honeypot.net/audio/

BTW I've read that it encodes a bit worse than Lame.

Varthall