This page is a big list of diskette, cassette, memory dump, and other data formats which mess does, doesn't, or partially supports.
| Format types, sorted from 'worst' to 'best' |
| Format type | Details |
| Cooked | predecoded data, typically with sector headers, footers, checksums stripped off, concatenated into a single large stream. Usually dumped at OS level (such as with dd or rawread, on ibm compatible systems). Least accurate to still be usable |
| Cooked w/ global header | same as cooked but with some general information about the disk, possibly label or other timing info that isn't track or sector specific |
| Cooked w/ track headers | same as cooked but has extra metadata for each track. may be equivalent to below for hard-sectored disks |
| Cooked w/ sector headers | same as cooked but has extra metadata for each sector |
| Observational | Stores the result of every command you can do on the floppy controller (read ids, read sectors, read track, etc) |
| Raw | raw, demodulated representation of NRZ, FM, MFM, or GCR data bits, with sector (or other low level structure) headers/footers/checksums intact (clock data may or may not be stripped depending on format) Notably, this does not handle cases where more than one physical modulation type is done on the same media (especially cassettes, usually irrelevant on floppies) as it will be demodulated incorrectly |
| Raw w/headers | raw, demodulated representation of NRZ, FM, MFM, or GCR data bits, with headers/footers/checksums intact (clock data may or may not be stripped depending on format) Since there is metadata, it is possible to store streams of data which were originally physically modulated in different ways |
| Flux | lowest level possible, a raw waveform of the magnetic flux of the media, typically sampled at a high clock rate. This is the only real way to handle some particularly brutal copy protection formats |
| Diskette Formats |
| File extension | Name of format | System(s) which use this | Type of image | Documented format? | Supported in MESS? | FULL degenerate-to-flux? |
| ? | Hobeta | Spectrum | ? | ? | no? 61 | ? |
| 2hd | X680x0 2HD disk image | Sharp X680x0 | cooked stream, exactly the same as .img | yes | yes  | ? |
| ad0 | Sydex Anadisk Image | All nec765/wd17xx | Cooked w/ OPTIONAL sector headers (otherwise same as img) | yes | no  | no |
| adf | Amiga Disk Format | Amiga | Cooked stream | Yes | yes | readonly |
| adz | Gzipped Amiga Disk Format | Amiga | same as adf. rename to .adf.gz and expand for .adf | yes | ? | no |
| atr | Nick Kennedy's Atari Disk Image | Atari Computers/drives | Cooked w/ global header | yes | yes | no |
| atx | Jorge Cwik's VAPS Atari Disk Image | Atari Computers/drives | mixed? raw/cooked? dump of data with lots of metadata? | partial(pending) | no | no |
| cpt | CP/M Transfer Image? | ?All? nec765/wd17xx or maybe only FM formats | ? | ? | no? | no |
| di | Kolja Koischwitz & Christian Kruger's disk image | Atari Computers/drives | ? | ? | no | no |
| di #2 | ? | TI 99/4a? | ? | ? | no | no |
| do | Apple II disk image | Apple II series | Cooked stream of 512byte sectors in DOS order (T0S0, T0S1, etc.) | yes | ? | no |
| d64 | 1541 Disk Image | C64/C128 | Cooked stream (single sided 180k) | yes | partially | no |
| d64(extended) | 1541 Disk Image, extended | C64/C128 | Cooked stream w/sector errormap (single sided 180k) | yes | partially as non-extended d64, errormap ignored | no |
| d67 | 2040 Disk Image | CBM/PET | Cooked stream, single sided 160k, same as d64 except last track is 35 | yes (vice source) | ? | no |
| d71 | 1571 Disk Image | C64/C128 | Cooked stream (double sided 360k) | yes | not yet | no |
| d71(extended) | 1571 Disk Image, extended | C64/C128 | Cooked stream w/sector errormap (double sided 360k) | yes | not yet | no |
| d80 | 8050 Disk Image | CBM machines | Cooked stream (single sided) | yes | no | no |
| d81 | 1581 Disk Image | C64?/C128 | Cooked stream ? | yes | no | no |
| d82 | 8250 Disk Image | CBM machines | Cooked stream (double sided) | yes | no | no |
| dcm | Bob Puff's Disk Communicator | Atari Computers/drives | ? | limited documentation (see http://www.crowcastle.net/preston/atari/dcmtoatr-1.4.c | no? | no |
| dim | X680x0 disk image | Sharp X680x0 | cooked stream w/ global header, similar to .img but with header | ?maybe? | yes | ? |
| dmk | ?name? | All nec765/wd17xx | Cooked w/global and sector headers | yes | no? | no |
| dms | Disk Masher System | Amiga | Cooked, supports compression | ? | No | No |
| dsk | Extended DSK format | Amstrad CPC and Sam Coupe, but format can probably handle all nec765/wd17xx | Cooked w/global, track, and sector headers | yes | yes (CPC only) 552 | no |
| dsk #2 | Apple Diskette dump | Apple II series | ? | ? | ? | no |
| dsk #3 | Sam Coupe Diskette dump | Sam Coupe | Cooked stream | Yes | Yes | no |
| dsk #4 | ? | Spectrum | ? | ? | no? 61 | ? |
| dsk #5 | TI99 sector dump (aka v9t9) | TI-99*, Geneve | Sequence of sector contents, no headers | yes | Yes | no |
| dtk | TI99 track dump (aka pc99) | TI-99*, Geneve | Cooked w/track and sector headers | yes | Yes | no |
| fdi | Floppy Disk Image | ZX Spectrum, and possibly others | cooked dump of diskette but done sector by sector, has some metadata and track headers | yes | no 61 | no |
| fds | Nintendo Famicom Disk System Image | Nintendo Famicom Disk System | Cooked dump of disk data with gaps, id, and checksum for each sector stripped. 2 formats. Note that FDS disks are SPIRAL disks and so really have one very long track on them. | yes (at least one format?) | yes (at least one format?) | no |
| g64 | 1541 Raw GCR Dump | C64/C128 | Raw GCR stream (single sided 180k) | yes | not yet | no |
| g71 | 1571 Raw GCR Dump | C64/C128 | Raw GCR stream (double sided 360k) | yes | not yet | no |
| hdm | X680x0 2HD disk image | Sharp X680x0 | cooked stream, exactly the same as .img | yes | yes | ? |
| imd | Dave Dunfield's ImageDisk Format | All nec765/wd17xx | Cooked w/global, (?track?) and sector headers | Dave Dunfield's clone of teledisk, documented and open source | no | no |
| img | Diskette Image | IBM PC, others | Cooked stream, interleaved by track/side where applicable. typically produced by dd or rawread or winimage. some winimage versions append a checksum header. | yes | yes | no |
| img #2 | Diskette Image | ?ZX Spectrum? | Cooked stream, one whole side then the other | yes | no 61 | no |
| imz | Zipped Diskette image | IBM PC, others | same as img. rename to .zip and unzip for .img | yes | no | no |
| ipf | Interchangable Preservation Format (CAPS/SPS) | Amiga, IBM PC, others | mixed flux/raw/cooked dump of data with lots of metadata, in IFF type file | Library source available | Yes | Yes |
| lib | Sam Coupe ?program library? | Sam Coupe | ? | ? | ? | no |
| mdr | Spectrum Microdrive dump | Spectrum | ? | ? | no? 61 | ? |
| mfi | Mess Floppy Image | Any | Flux | yes | Yes | Yes |
| mfm | HxCFloppyEmulator floppy image | Amiga | Raw w/headers | Yes | Yes | Yes |
| mgt | Sam Coupe | Sam Coupe | Same as .dsk | Yes | Yes | Yes |
| mgt #2 | ? | Spectrum | ? | ? | no? 61 | ? |
| msa | Magic Shadow Archiver | Atari ST | Cooked stream | Yes | Yes | Yes |
| nib | Apple II Nibbled? Disk image | Apple II series | ? | ? | ? | no |
| nib #2 | Used by No-Intro (Commodore - 64 (PP)) | Commodore - 64 | ? | ? | No | ? |
| nst | NorthStar HardSectored Diskette | Northstar ? | Hard sectored floppy image (index hole) | ? | no? | no |
| pak | ?Sam Coupe? | ?Sam Coupe? | ? | ? | ? | no |
| pro | Stephen Tucker's APE ProSystem | Atari Computers/drives | ?, handles copy protection | author has not been asked yet, so no | no | no |
| po | Apple II disk image | Apple II series | Cooked stream of 512-byte sectors in ProDOS order (0,1,2,3,etc) | yes | ? | no |
| sad | Sam Coupe Diskette dump | Sam Coupe | Cooked stream with header, different track/side order to .dsk. Version 2 is the same as version 1 just gzipped | Yes | Yes | no |
| scl | ? | ZX Spectrum | ? | ? | no? 61 | no |
| scp | SpartaDOS Disk Copy file | Atari Computers/drives | ?, basically a compressed atr | no, can be converted to other formats using software on an atari | no | no |
| sdf | Sam Coupe | Sam Coupe | Cooked with sector headers | Yes | Yes (partially) | No |
| st | ST image | Atari ST | Cooked stream | Yes | Yes | Yes |
| stx | PASTI image | Atari ST | Obs. | Mostly | No | No |
| td0 | Sydex Teledisk Image | All nec765/wd17xx | Cooked w/global, (?track?) and sector headers, sometimes compressed. more than one version exists, check header | yes (RE'd by Dave Dunfield) | no 99 | no |
| trd | TR-DOS disk image | ZX Spectrum | ? | ? | no? 61 | no |
| uef | Universal ?Emulator? Format? | Electron and BBC/Acorn Archimedes | ? | yes | no | no |
| vdk | ? | CoCo | ? | yes | yes | no |
| vdk #2 | ? | Dragon | ? | yes | no 956 | no |
| xdf | X680x0 2HD disk image | Sharp X680x0 | cooked stream, exactly the same as .img | yes | yes | no |
| xfd | XFormer Disk | Atari Computers/drives | cooked stream, w/o header) | yes | yes | no |
| Cassette Formats |
| File extension | Name of format | System(s) which use this | Type of image | Documented format? | Supported in MESS? | FULL degenerate-to-flux? |
| blk | ? | Spectrum | ? | ? | no? 61 | ? |
| cas | Ernest R. Schreurs' cassette format | Atari, ?others? (same format or not?) | cooked binary image of waveform | yes | yes | yes |
| cas #2 | ? cassette format | older fMSX98/AT CAS format | ? | doubtful, as marat is involved | ? | no? |
| cas #3 | ? cassette format | standard fMSX-DOS CAS format | ? | doubtful, as marat is involved | ? | no? |
| cas #4 | ? cassette format | SVI-318/328 format | ? | ? | yes | yes |
| cas #5 | ? cassette format | TRS-80 and clones / EACA Colour Genie | ? | yes | partial (no cgenie) 1292 | yes |
| cdt | Amstrad CPC Cassette | Amstrad CPC | Identical to .tzx format but with some guidelines and maybe one or two extensions | yes | yes | yes |
| csw | Compressed Square Wave | ZX spectrum, others | Raw, quantized binary image of demodulated waveform ?at a static clock rate?, compressed | yes | ? | ? |
| itm | ? | Spectrum | ? | ? | no? 61 | ? |
| ltp | ? | ZX Spectrum | ? | yes via source code | ? | no? |
| nas | Nascom Cassete Dump | Nascom 1 | Cooked binary dump of cassete data with start/stop/parity bits stripped off | ? | pending | ? |
| pan | ? | Spectrum | ? | ? | no? 61 | ? |
| spc | ? | Spectrum | ? | ? | no? 61 | ? |
| tap | C64 Tape format | All commodore systems, possibly others | Raw stream, delta encoded for pulse lengths. three versions (v.2 is C16 only) | yes | yes | yes |
| tap #2 | Spectrum | ? | ? | ? | no? 61 | ? |
| tzx | ZX tape format | originally ZX spectrum, format can cover several systems | raw and partly cooked stream with lots and lots of metadata, might be lossless. many subtypes exist. | yes | partial (only some of the subtypes) | yes |
| wav | Waveform audio format | many systems | Flux dump in RIFF format | yes (well, mostly, .wav has some weird extra features which are not well documented), see also WAV | for some systems | already in flux format |
| zxs | ? | Spectrum | This format is completely different from the one with the same extension used for snapshots | ? | no? 61 | ? |
| Cartridge formats |
| File extension | Name of format | System(s) which use this | Type of image | Documented format? | Supported in MESS? |
| bin | | All systems with carts | Raw binary dump on the cart. Most of the formats below are actually bin files with renamed extension | | mostly |
| a26 | | Atari 2600 | | | yes |
| a52 | | Atari 5200 | | | yes |
| a78 | | Atari 7800 | | | yes |
| abs | | Atari Jaguar | | | yes |
| ccc | | Radio Shack Color Computer | | | yes |
| col | | Coleco Colecovision | renamed .bin? | | yes |
| cpr | | Amstrad CPC+ / GX4000 | RIFF formatted in 16kB chunks | yes | yes |
| crt | | Many systems (is it always the same?) | | | sometimes |
| crt #2 | | C64 cart format (many substypes) | | yes | preliminarly |
| dck | Timex memory expansions | Spectrum | | | no? 61 |
| dol | | Nintendo Gamecube | | | NO, and, in accordance to MAME/MESS policy, will NOT BE SUPPORTED until the Gamecube is no longer having new games made for it. Come back in a few years. |
| gam | | GCE Vectrex | | | yes |
| gb | | Nintendo Game Boy | renamed .bin | | yes |
| gbc | | Nintendo Game Boy Color | renamed .bin | | yes |
| gba | | Nintendo Game Boy Advance | renamed .bin | | not yet (driver pending submission) |
| gen | | Sega MegaDrive / Genesis | renamed .bin | | yes |
| gg | | Sega Game Gear | renamed .bin | | yes |
| int | | Mattel Intellivision | renamed .bin, usually has a .cfg with it | | preliminary |
| itv | | Mattel Intellivision | renamed .bin, same as .int | | preliminary |
| j64 | | Atari Jaguar | | | yes |
| jag | | Atari Jaguar | | | yes |
| jrc | | IBM PC Jr. | | | yes |
| lnx | Handy emulator format | Atari Lynx | Cooked up data: header + cart content | Handy source | partial (no support for carts with data in bank 1) |
| lyx | | Atari Lynx | renamed .bin | | partial (no support for carts with data in bank 1) |
| md | | Sega MegaDrive / Genesis | | | yes |
| min | | Nintendo Pokemini | renamed .bin | | yes |
| mx1 | | MSX1 / MSX2 | | | yes |
| n64 | | Nintendo N64 | | | yes? |
| nes | iNES format (many subtypes called mappers) | Nintendo Entertainment System / Famicom | Cooked up data: Header (with scarce cart hardware info) + PRG chip content + CHR chip content | yes | partial (not all mappers) |
| nds | | Nintendo DS | | | NO, and, in accordance to MAME/MESS policy, will NOT BE SUPPORTED until the DS is no longer having new games made for it. Come back in a few years. |
| ngp | | SNK Neo-Geo Pocket | renamed .bin | | yes |
| npc | | SNK Neo-Geo Pocket | renamed .bin | | yes |
| ngc | | SNK Neo-Geo Pocket | renamed .bin | | yes |
| pce | | NEC PC-Engine | | | yes |
| rom | | Many systems (is it always the same?) | | | sometimes |
| rpk | Rom package | mainly TI-99* | Zip archive of bin dumps with XML layout file | yes | yes |
| sc | SG-1000 card format | Sega SG-1000 Mark II / SC-3000 | renamed .bin | | yes |
| sfc | | Nintendo SNES / Super Famicom | | | yes |
| sg | SG-1000 cart format | Sega SG-1000 / SG-1000 Mark II / SC-3000 | renamed .bin | | yes |
| sgb | | Nintendo Super Game Boy | renamed .bin | | yes |
| smc | | Nintendo SNES / Super Famicom | | | yes |
| smd | | Sega MegaDrive / Genesis | | | yes |
| sms | | Sega Master System / SG-1000 Mark III | renamed .bin | | yes |
| stc | | Atari ST | | | yes |
| sv | | Watara SuperVision | renamed .bin | | yes |
| swc | | Nintendo SNES / Super Famicom | | | yes |
| tgc | | Tiger Game.com | renamed .bin | | yes |
| v64 | | Nintendo N64 | | | yes? |
| vec | | GCE Vectrex | | | yes |
| ws | | Bandai WonderSwan | renamed .bin | | yes |
| ws #2 | | Watara SuperVision | renamed .bin? | | yes |
| wsc | | Bandai WonderSwan Color | renamed .bin | | yes |
| z64 | | Nintendo N64 | renamed .bin | | yes |
