Path: chuka.playstation.co.uk!news From: "Stanley Lim" Newsgroups: scee.yaroze.programming.sound Subject: Re: mp3 on yaroze.... Date: Fri, 29 Oct 1999 18:25:18 +0800 Organization: PlayStation Net Yaroze (SCEE) Lines: 81 Message-ID: <7vbsj3$7l1@chuka.playstation.co.uk> References: <7v2toh$6s1@chuka.playstation.co.uk> <7v4171$6kf1@chuka.playstation.co.uk> <7v7481$f4p1@chuka.playstation.co.uk> <38197cd9.204929122@news.playstation.co.uk> NNTP-Posting-Host: qtns04311.singnet.com.sg X-Priority: 3 X-MSMail-Priority: Normal X-Newsreader: Microsoft Outlook Express 5.00.2615.200 X-MimeOLE: Produced By Microsoft MimeOLE V5.00.2615.200 Toby Sargeant wrote in message news:slrn81f3u4.kiq.tjs@longford.cs.monash.edu.au... > On Wed, 27 Oct 1999 22:32:30 GMT, Steven Osman wrote: > >I agree... I'm not sure it's THAT impossible... but then again, I > >really don't know enough about mp3. What I do know is that the > >resulting data (post processed) needs to sustain only 150k/second (I > >doubt that the output of mp3 exceeds that of a CD). That doesn't seem > >like an impossible task. > > > >But then again, I really DON'T know enough about mp3. > > A 486dx2-66 (twice the clock speed of the playstation CPU) can _just_ play > a mono 128k mp3, at pretty much full CPU utilisation. I'm not so sure about that.... Let's look at the Philips Nino 312(A Palmtop PC) having a processor of R3000(same as Yaroze) but with 8mb ram is able to play MP3. So I think that it is possible. > > mp3 playing also relies on floating point operations, and seeing as the PSX > CPU has no FPU, this has to be emulated. > > The playstation plays ADPCM samples only. Thus, there's the added overhead > of converting from raw sample data to ADPCM format (which, I might add, is > a SONY proprietary format, information on which is not available to yaroze > members). > > All of this adds up to a very slow mp3 player. > > That being said, there's a *possibility* that if you could write an integer > based mp3 player that used the GTE for matrix operations in order to > parallelise the decoding of the mp3, there's a chance that you could play > mp3's in realtime. In order to do it, however, you'd need to be very familiar > with mp3 decoding and very familiar with the PSX at a hardware level. > > Anyone who's programming a yaroze has access to a PC anyway, so I don't see > why having the playstation play mp3s is so interesting to people (apart, I > guess, from the obvious geek factor). Well it's a challenge of it to create a MP3 Player on Yaroze. > > If you want a component unit that will play mp3s, ripping the guts out of > an old vcr, and sticking an old pentium motherboard with a soundcard, > ethernet and a serial port driven LCD display in their place would be a > much cooler option. > > Alternatively, there's apparently a hardware addon like an Action Replay > that will allow the psx to play mp3s. I don't know anything more than that, > though. > > >Steven > > > >On Wed, 27 Oct 1999 23:05:33 +0800, "Stanley Lim" > > wrote: > > > >>Issit possible to code in Assembly in Yaroze? Do you have any idea? > > Definitely, but this won't help you write an mp3 player. If you want to learn > more, get a MIPS programmers manual, and have a look at as.exe (I'm assuming > that the dos compiler has an accessible version of as), which is the assembler > backend for gcc. if you compile a .c file with -S (note, capital s, not > lowercase) the output will be the assembler conversion of the .c file. That's > as good a place as any to start learning about the input format that as > accepts. > > Toby.