JMA Compression

Post by **Nach** » Fri Jan 28, 2005 1:28 pm

Okay, who here has been blabbing on the other compression forums?

Nightcrawler · Post by **Nightcrawler** » Fri Jan 28, 2005 2:35 pm

Nach wrote:
Bent wrote:x86 is a bit tougher than MIPS because of limited amounts of registers right?
When writing a complex function, yes the register limit is a problem.

I wouldn't really say it's a problem. It just forces you to do more management using memory instead of registers.

Being that I have programmed for many microcontrollers, x86 has a WEALTH of registers. In fact, MIPS chips have too many general purpose registers for me because I'm so used to working with such confined resources. So it depends on how you look at it. I don't believe any assembly language is really 'tougher' than any other. They all have various quirks and differences, but that's about it.

Bent wrote: MIPS compatable processors had something like 32 general purpose registers of which most of them were almost always usable. Does the x86 have some 32bit registers and some 16bit?
The 16 bit registers are part of the 32 bit ones. Meaning you can access a 32 bit reg half way if you want.

x86 registers are split into 8,16, and 32 bit sizes. You can access any of the three and not affect the data in the rest of the register.
For example if you perform an 8-bit operation the other 24-bits are untouched.

Bent wrote: Also, how much of a difference does the fact that it is a CISC CPU instead of a RISC CPU make? Is the instruction set much larger?
I don't know the full instruction set of MIPS and x86, but I think x86 has a larger set.
To be honest though, I only use a dozen opcodes or so on a regular bases anyway.

Well RISC CPU's work differently in the sense that ideally most every opcode is executed in one CPU cycle. The are more efficient than CISC CPU's. The may have a more limited instruction set, but they are far better at executing the ones they have. The size of the instruction set as opposed to CISC CPU's varies. The R3000 MIPS chip has a pretty small set, but some of the more advanced 64-bit MIPS chips add a good deal of baggage to deal with the bigger size registers and/or coprocessors/FPU units.

From a programming point of view, the difference is minor. Most of the everyday instructions you use are still available in both architectures. Occasionaly you'll need to do something in a different way with your RISC chip, but it's for the better. Our modern day P4 and AMD XP chips have essentially mutated into a RISC like chip.

Post by **Nach** » Sun Feb 06, 2005 12:52 pm

SNEeSe in CVS now supports JMA

Jagasian · Post by **Jagasian** » Sun Feb 13, 2005 8:29 pm

Does NSRT support automatic similarity merging as seen in GoodMerge? I am trying to convince !!!CENSORED!!! to switch to NSRT, but they seem to like 7z compressed GoodMerge sets because they are so small. However, NSRT has JMA support which is better than 7z and NSRT is just simply better for SNES ROM collections for many reasons, maily due to the failings of GoodSNES from which GoodMerge derives. So I wanted to know if NSRT supports something like GoodMerge but with JMA, and if so, on a complete SNES ROM collection, what is the total size difference between 7z-GoodMerge and JMA-NSRT-Merge?

I realize that emulators don't necessarily support multi-ROM archives yet, but for other reasons, people still like merged ROM sets because of organizational and space saving reasons. Also, if people can be convinced to keep their sets in NSRT audited JMA compressed form, the entire world will be better, regardless of merged or non-merged. Hence the reason that I am trying to get people to ditch GoodSNES and GoodMerge.

Also, what is going on with the NSRT web site. I haven't been able to access it for days now.

Post by **Nach** » Sun Feb 13, 2005 9:05 pm

I'm working on a feature to allow NSRT to merge ROMs, not sure if it'll be ready for the next release or not.

Once that's done, I probably would make ZSNES support multiple files in a zip/JMA.

My host switched servers, so my site currently has some technical difficulties.

anewuser · Post by **anewuser** » Sun Feb 13, 2005 9:07 pm

Hey, look! Nach beat me to it so this post makes no sense now!

Edited.

Jagasian · Post by **Jagasian** » Mon Feb 14, 2005 5:34 am

Nach wrote:I'm working on a feature to allow NSRT to merge ROMs, not sure if it'll be ready for the next release or not.

Once that's done, I probably would make ZSNES support multiple files in a zip/JMA.

My host switched servers, so my site currently has some technical difficulties.

Merged-sets in NSRT and emulator support for them will definitely cause NSRT to become the standard SNES ROM auditing tool and JMA the standard SNES compression format simply because NSRT ROM sets will take up less space, less bandwidth, will be more organized, the ROMs themselves will be of higher quality thanks to better auditing, and last but not least they will have emulator support. NSRT ROM sets will be better in every way than GoodSNES or GoodMerged ROM sets.

I like the idea of a tool that concentrates on quality SNES support, as opposed the GoodTools which concentrate on quantity at the expense of quality. These things are always a chicken and egg kind of thing... unless a Jack of all trades comes along, like you Nach

BTW, I can access the NSRT web site now.

stale · Post by **stale** » Tue Feb 15, 2005 9:10 am

coughromsiteinmumblejagasianspostahem

Jagasian · Post by **Jagasian** » Wed Feb 16, 2005 4:30 am

Ok, I censored it. I thought it was ok, as long as I didn't link the site. Can such sites not even be mentioned by name? In 100 years, people will look back on such sites with kindness because who will give a damn about copyrights then? They will care if certain games were lost forever because of copyrights.

Tallgeese · Post by **Tallgeese** » Wed Feb 16, 2005 4:31 am

Jagasian wrote:Ok, I censored it. I thought it was ok, as long as I didn't link the site. Can such sites not even be mentioned by name? In 100 years, people will look back on such sites with kindness because who will give a damn about copyrights then? They will care if certain games were lost forever because of copyrights.

...So, are you out of your ideal dream world yet?

adventure_of_link · Post by **adventure_of_link** » Wed Feb 16, 2005 4:55 am

Jagasian wrote:In 100 years, people will look back on such sites with kindness because who will give a damn about copyrights then? They will care if certain games were lost forever because of copyrights.

Bzzt. Wrong. There will always be the chance that Nintendo or whoever made the game can re-release it on a newer system, and revive the copyrights. Just look at the Gameboy Advance, that was pretty much Remake-City, and the DS is sorta like that now.

Jagasian · Post by **Jagasian** » Fri Feb 18, 2005 2:53 am

adventure_of_link wrote:
Jagasian wrote:In 100 years, people will look back on such sites with kindness because who will give a damn about copyrights then? They will care if certain games were lost forever because of copyrights.
Bzzt. Wrong. There will always be the chance that Nintendo or whoever made the game can re-release it on a newer system, and revive the copyrights. Just look at the Gameboy Advance, that was pretty much Remake-City, and the DS is sorta like that now.

In other words, hundreds of years from now, a very few people will be allowed to do things because they are somehow related to somebody who did them a very long time ago. If copyrights existed a thousand years ago, Shakespear would be owned by his decendents, etc...

...seems really lame.

Post by **Nach** » Fri Feb 18, 2005 5:19 am

Status Update. A standalone compressor has just gone into beta.

If you're on the NSRT Test Team, you can get a WIP from my site.

Post by **Agozer** » Fri Feb 18, 2005 1:49 pm

Nach wrote:Status Update. A standalone compressor has just gone into beta.

If you're on the NSRT Test Team, you can get a WIP from my site.

Great work Nach, I'll check it out.

kieran_ · Post by **kieran_** » Fri Feb 18, 2005 1:57 pm

Nach wrote:Status Update. A standalone compressor has just gone into beta.

If you're on the NSRT Test Team, you can get a WIP from my site.

Fantastic. Will it have a GUI, or must it be run from a command line?

Malcster · Post by **Malcster** » Fri Feb 18, 2005 11:29 pm

It's command line but Nach mentioned that he could easily whip together a right click context menu entry to compress and decompress stuff, if he could find his papers on how to do it. I'm sure he'll have it done by the time a standalone jma compressor gets released to the public.

Edit: I think he only mentioned windows context menus...

snkcube · Post by **snkcube** » Fri Feb 18, 2005 11:39 pm

Nach wrote:Status Update. A standalone compressor has just gone into beta.

If you're on the NSRT Test Team, you can get a WIP from my site.

Nice job Nach.

Jipcy · Post by **Jipcy** » Sat Feb 19, 2005 7:10 pm

Malcster wrote:It's command line but Nach mentioned that he could easily whip together a right click context menu entry to compress and decompress stuff, if he could find his papers on how to do it.

I don't think its particularly complicated to create a context menu entry. All that is necessary is for his program to support the variables that Windows uses when doing things like that. Such as "%1" representing the filename of the file you right-clicked.

Post by **Nach** » Sat Feb 19, 2005 7:30 pm

Go back a few pages, you'll see I already displayed how to add right click support.

ZSNES board

JMA Compression

NSRT Merge Support?

Re: NSRT Merge Support?