Changes

It wouldn't be so bad if not for the fact that the game data itself is often times only a fraction of the actual disc size - for instance, the ''Super Mario 25th Anniversary'' Wii disc itself is a 4.7GB game, when really the actual game data is only a single SNES ROM (12 MB of useful data, to be precise) and nothing else. Naturally, one would want to trim this extra "fat" as much as possible, which is what this page aims to help to achieve. Most of the information here is based partially on this [https://www.reddit.com/r/emulation/comments/3g933n/guide_reduce_the_size_of_your_ps2_gc_wii_x360_ds/ guide].

* '''Gain:''' Not Immediate (ISO size doesn't change). ECM only zeroes out redundant error correction data (, but in some rare cases this data may be used for anti-piracy, hence corrupting the dump!). When coupled However it does achieves drastic size reductions when compressed to a compressed an archive format (7zip/gzip/zip) however it achieves drastic size reductions.* '''Tools Used:''' PakkISO or ECM Tools (from emuparadise download page). Drag-and-drop the iso on ISO onto the specific specified tool, then compress it with 7zip.

* '''Can be reverted?''' Yes, using the same tools (unECM). However, however there's is data loss (error correction data) which can damage a select few games. Check the hash with Redump to make sure nothing was altered.

* '''Playable on Emulators?''' Only on recent SVN builds of PCSX-R and ePSXe (they also support 7zip/gzip/zip archives so use them with ECM). Other emulators don't, so you convert manually the ECM dump to an ISO dump whenever you want to play it.

* '''Can be reverted?''' Yes. (For homemade EBOOTs) it can be done by using the same tool, to generate the BIN+CUE files; (for . For commercial releases from PSN) you will have to use [https://github.com/xdotnano/PSXtract PSXtract]. There's data loss, although but it's negligible in terms of functionality.

* '''Playable on Emulators?''' RetroArch, PCSX-R, and ePSXe. PlayStation 3's ps1_netemu (can also use it after packaging it into a PS1 Classic and installation of installing said package).

Official PBP is the official format used by Sony for the PS1 Classics on PSP and PS3. Audio tracks may be compressed in ATRAC3, or as raw PCM (unsupported on PS3's ps1_netemu, supported on PSP only by the earliest versions of POPS or the newest ones with the [http://wololo.net/talk/viewtopic.php?f=28&t=41330&start=60 cdda_enabler plugin])

Often, times you can just open the ISO in UltraISO and find the dummy files. Sometimes they're obviously are obvious looking files , like DUMMY.BIN, DATA0.BIN (or .DAT), DUMMY.DAT, etc. Or , or are folders named with names like "PADDING" and stuff like thatsuch. You can look into the files (with a hex editor) to see if they're obvious obviously padding data (usually the offsets will be full of 00/FF, though sometimes it's not as obvious). However, you must never mess with LBA and TOC when removing padding. <!--So you try to change the size of the padding file inside the ISO to 0 MB or alter it directly with a hex editor so that it's all zeroed out.--><!--Wording is too weird to figure out what it's say, will fix when more information is obtained-->

* '''Gain:''' Not Immediate (ISO dump size the same). Coupled , however when used with compression, however... the gain is really noticeable.