Enhancement: Support for 'shrunk' ISO/BIN (Padding removal)

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|ENHANCEMENT POSSIBILITY:|
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Since the PSX games are on Compact Disc media, the discs were pressed and were 
created using extra 'padding' which was used to fill the rest of the disc and 
create a full 600-700MB image. Very few games utilized the entire capacity of 
the disc's space so removing the padding can GREATLY decrease the filesize 
allowing for more free space and in some cases, boosts in load times for 
certain games.

I would like to see an enhancement for WiiSX/CubeSX that supports images that 
have that extra padding removed. As long as the disc structure is intact, it 
should be able to play just fine. Several PSX emulators among different 
platforms support it and I believe the original PSX console supports it as well 
(I would have to test this theory). I don't expect to see a speedup, although, 
it would be nice. Just allow for compatibility with the games that can use it. 
Off the top of my head, Mortal Kombat Trilogy uses it A LOT! It shrinks a 600MB 
game down to about 60MB and will play basically perfectly on anything that 
supports the size difference. You can see where that would come in handy. Many 
games do NOT support this dramatic of a shrink-down in file size. some can 
actually be made larger by attempting to shrink it. It should still be 
something to consider. The way I see it, if one person uses it, more probably 
use this method too. It saves space without sacrificing the quality of the 
experience. If people have more free space to use, they will use it for more 
games, thus more testers for this emulator. Hope you like the idea! Thanks for 
all the hard work!!! ^_^

------------------------Actual Test Results Below--------------------------

EXPECTED RESULTS:

Expected the game to work just as MKII(NTSC-J) did, which was pretty much 
flawless (no pun intended), got a code dump during/after spinning dragon logo.

HLE BIOS or a REAL BIOS:

I tried using both, Same results either way. Probably a feature not implemented 
in.

VIDEO SETTINGS:

I only tested this using the Dynamic recompiler.

PLATFORM TESTED:

Only tried on Wii thus far.

Original issue reported on code.google.com by gygabyte...@gmail.com on 13 Jul 2010 at 4:11

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The padding files are there for a reason.

1. All psx discs are limited to the 71min standard this is because laser 
couldn't read past that without problems so companies that where pressing them 
onto cheaper 74min discs added a dummy file to the end of disc to make the last 
3minutes of the disc redundant and for the newer 80min discs you need to a 
dummy file to cover the last 9mins.

2. Sometimes dummy files are used to shift the larger files to the outer part 
of the disc to reduce loading although smaller files that are constatly being 
read in-game can be move there too.

3. Be careful when rebuiling psx games some of them contain LBA checks the game 
won't load if they aren't placed at specific LBA address.
Also sometimes when rebuiling / replacing files you may need to add new license 
data this is because most image programs destrory it as well as the EDC/ECC.
The volume identifiers System and Application also need to set to PLAYSTATION 
to make a vaild IS09660 MODE2/FORM1/2352 image don't make the mistake of adding 
the Joliet or UDF filesystem either.

Original comment by noddy...@hotmail.co.uk on 15 Jul 2010 at 5:51

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I agree with what you are saying. However, if you are very careful and go 
through the process completely you can easily create ISO/BIN files that are 
shrunk down and play without any problems at all. A simple Google search will 
bring up a way to shrink down ISOs. It is a shot in the dark most times but if 
it is successful, you will have a fully working ISO/BIN that requires less 
space on your HDD. Using CDGENPS2 on Windows is VITAL to getting this process 
to work. That program rebuilds the ISO file and generates a new license to the 
disc after processing. All the user needs to worry about is the LBA addresses.

The padding files are not needed for a select few titles, as noted Mortal 
Kombat Trilogy can play fine without it. I have tested this on many systems and 
emulators and it has always worked fine. I'm sure there are others that work 
just as well too, I just haven't tested them as throughly yet.

LBA checks are the most important part of the rebuilding process. If you forget 
to place them in their specific order 9/10 the game will not work. So this is a 
very important part of removing the padding on the discs. If this is not fixed, 
the mostly likely will not work.

Overall, I understand your comments and concerns for my enhancement but I 
assure you, a few select games and probably many more that I am unfamiliar with 
work just fine as long as the important things are double checked before 
rebuilding, one of which is the LBA.

UPDATE ON INITAL TESTING: I must also add an update to my above post. It would 
seem I forgot to test the actual Mortal Kombat Trilogy before I submitted the 
enhancement. MK Trilogy's authentic disc/BIN doesn't load properly either. It 
also code dumps during loading the dragon logo. So perhaps support for padding 
removal is already in the emulator, I just sadly chose a poor choice for game 
to test it with. At the least, Mortal Kombat Trilogy is a broken game for the 
moment with this emulator. So that should be on the list for possibly being 
fixed in the next release.

Original comment by gygabyte...@gmail.com on 15 Jul 2010 at 10:43

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CDGENPS2 will make vaild images but it won't add a ps1 license screen you'll 
still have to do that manually with bootedit and patchit as it's a ps2 iso tool 
which don't contain this license data.
Don't use the psxcdgen either it has a fault where the images it makes are 
corrupt so you are right in saying use cdgenps2 instead but it shouldn't matter 
what image program you use as long as the first file is at lba 23.

One of the ways to check if the game can run without any problems when the 
dummy files are removed is try and play it through psxfin v1.3 if it has any 
problems it'll say them in the debug window the most common error being 
something about the cd sector being out of range.

Original comment by noddy...@hotmail.co.uk on 16 Jul 2010 at 3:32