Differerence between mdf and mds files

[Jerry71]

I'm converting my Sega CD games to bin and cue files. I'm using IsoBuster. I opened up the mdf file and converted, it seemed to work. But now I'm wondering about the mds file, like does that just get converted automatically?

So I opened up the mds file in IsoBuster and did the same extraction and conversion. It seemed like it was just doing the same thing as it did with the mdf file, another cue/bin conversion. But when it was done, I compared the end results, and the two sets of cue/bin files had different sizes.

Anybody know why that would happen?  Which file should I convert in IsoBuster?  Or do both just get converted when you select either one?

[Jerry71]

I know I really shouldn't care about this, because all of the games work fine.  But I'm just curious.  Anybody?

[Nologic]

The MDS file is the index file for the MDF...much like a CUE file is an index file for a BIN file...so ideally you actually convert the MDS file.

Heh and your wrong...this is something you should care about...as with out using the MDS file you'll end up with a less accurate conversion.

Oh and while using CUE+BIN doesn't really matter with Sega CD...is there are reason for the conversion? As its my understanding MDS+MDF is a more accurate format.

[Jerry71]

I guess my question is that when I'm in IsoBuster, which file should I select to convert?  The mdf or the mds?  The way it looks to me, choosing either one converts them both.  In other words, no matter which one I choose - mdf or mds - I end up with a working bin and cue conversion, and the game works both ways too.  I was just wondering why the file sizes are a little different depending on which file I actually selected to convert.

I tried running the Sega CD games with the mdf/mds files, but it wasn't working.  I read on another forum that the Fusion emulator won't work with these files.  Is that true?  If I have that wrong, then I don't need to bother converting at all, I just need to figure out how to get them working the way they are.

[Nologic]

Well Fusion won't load MDS+MDF directly, but it will read them just fine from a virtual drive.

Anyways if you convert always select the MDS file bar none...if you don't you will in all likely hood be missing some needed data and at worse end up with digital pea soup thats not usable at all.

[Jerry71]

Hmmm.  Is there a command line that will enable the virtual drive?  Sorry if that's a stupid question, but I'd really like use the mdf/mds files and avoid converting all of these roms, there are a ton of them.

[Nologic]

Well you'll need Virtual CD\DVD software to be installed first. There are a number of them so depending on what you have installed will determine the mounting\unmounting command line strings.

Alcohol 120% ShareWare
Alcohol 52% FreeWare
Supports: *.bin; *.bwi; *.bws; *.bwt; *.ccd; *.cdi; *.cue; *.img; *.iso; *.mds; *.nrg; *.nri; *.pdi; *.sub
"C:\Program Files\Alcohol Soft\Alcohol 52\AxCmd.exe" D: /M:"[RomPath]\[RomFile]"
"C:\Program Files\Alcohol Soft\Alcohol 52\AxCmd.exe" D: /U

Alcohol Command Launcher (AxCmd.exe) allows you to mount and unmount image files on Alcohol virtual drives through command line parameters.

Syntax:
AxCmd.exe [drive:] [/M:path] [/U] [/L] [/?] [@cmd]

drive:
Specifies virtual drive letter or number.
Possible values are A to Z or 1 to 31.

/M:path
Mount an image file on a virtual drive.
Example: AxCmd.exe V: /M:c:\images\cd1.mds
This example will mount image file cd1.mds (located in images folder on drive C:) in Alcohol virtual drive that is using V: drive letter.
Note that if the full file/path name contains space character, then the file/path name need to be quoted for example: AxCmd.exe 1: /M:"C:\Documents and Settings\someone\My Documents\Alcohol 120\test 101.iso"
Returns drive letter when success or 1 when failure occurs.

/U
Umount an image from a virtual drive.
Example: AxCmd.exe V: /U
Returns drive letter when success or 1 when failure occurs.

/L
Get the number of active Alcohol virtual drives.
Example: AxCmd.exe V: /L
Returns 0 if there are no active virtual drives.

/?
Display help.

@cmd
This parameter should be used together with /M parameter to execute a specified command after mounting an image file on a virtual drive.
Example: AxCmd.exe 1: /M:c:\images\cd1.mds @1:play.exe
This example will mount image file cd1.mds (located in images folder on drive C:) in first Alcohol virtual drive and then automatically run play.exe from this virtual drive.

DAEMON Tools FreeWare
Supports: *.b5t; *.bin; *.bwt; *.ccd; *.cdi; *.cue; *.iso; *.mds; *.nrg; *.pdi
"C:\Program Files\DAEMON Tools\daemon.exe" -mount 0,"[RomPath]\[RomFile]"
"C:\Program Files\DAEMON Tools\daemon.exe" -unmount 0

-lock
Used to lock the DLL operation to be sure no unauthorized program can load daemon.dll and use its functions. Used mainly in autostart (if 'Autolock' option is enabled), but can be used in command line too. Unlocking can be done from Virtual DAEMON manager or other GUI that is currently running. Note that locking has no effect on DAEMON Manager itself or other programs which have been 'authorized' by us to use the DLL.

-noicon
this option is used to prevent Daemon-Tools from creating a taskbar icon. It has no effect if DAEMON manager is already running or you specified another command (except 'lock') in the command line! DAEMON manager automatically exits after command is executed and does not create taskbar icon.

-mount <n>,<path>
Allows mounting images from command line (or shortcut).
where 'n' means DVD-ROM device number ('0' - '3' allowed) and 'path' is the full path to the image file.
Do not forget to set the path in quotes if it contains spaces!
Example: daemon.exe -mount 0,"c:\My Images\nameofimage.cue".

-unmount <n>
Allows unmounting images from command line.
where 'n' means DVD-ROM device number ('0' - '3' allowed)

-safedisc <on/off>
Allows turning Safedisc emulation on/off from command line.
'-safedisc on' enables emulation, '-safedisc off' disables it

-securom <on/off>
Allows turning Securom emulation on/off from command line.
'-securom on' enables emulation, '-securom off' disables it

-laserlok <on/off>
Allows turning Laserlock emulation on/off from command line.
'-laserlok on' enables emulation, '-laserlok off' disables it.

-rmps <on/off>
Allows turning RMPS emulation on/off from command line.
'-rmps on' enables emulation, '-rmps off' disables it.

MagicDisc FreeWare
Supports: *.000; *.bin; *.bwi; *.bwt; *.c2d; *.ccd; *.cdi; *.cif; *.dao; *.ima; *.img; *.md1; *.mdf; *.mds; *.nrg; *.p01; *.pdi; *.tao; *.uif; *.vaporcd; *.vc4; *.vcd; *.vdi; *.xa
"C:\Program Files\MagicDisc\miso.exe" NULL -mnt 1 "[RomPath]\[RomFile]"
"C:\Program Files\MagicDisc\miso.exe" NULL -umnt 1

-mnt [id] Filename
Mount CD/DVD image to the virtual CD/DVD-ROM which is specified by id.

-umnt [id]
Unmount the virtual CD/DVD-ROM which is specified by id

-sdrv Number
Set number of virtual drives. 0 to disable.

-vlist
List all virtual drives

Samples of mounting ISO image

miso.exe NULL -vlist

List all of the present virtual CD/DVD driver.
Please notes: miso.exe ignores the "NULL" parameters.
Result:

MagicISO Console v3.0.97
Copyright © 2002, 2003, 2004, 2005, 2006 MagicISO Inc.

The following is all of the present virutal CD/DVD drivers.

[1] C:\DVD.ISO (J:)
[2] No Media (K:)

miso.exe NULL -sdrv 3
Create 3 virtual drives.
Please notes: miso.exe ignores the "NULL" parameters.

miso.exe NULL -sdrv 0
Disable all virtual Drives.
Please notes: miso.exe ignores the "NULL" parameters.

miso.exe NULL -mnt j: "c:\backup\1.uif"
mount "c:\backup\1.uif" to virtual drive j:
Please notes: miso.exe ignores the "NULL" parameters.

miso.exe NULL -umnt 1
Unmount the first virtual CD/DVD-drives.
Please notes: miso.exe ignores the "NULL" parameters.

PowerISO ShareWare
Supports: *.ashdisc; *.b5i; *.bin; *.bwi; *.c2d; *.cdi; *.cif; *.cue; *.daa; *.fcd; *.gi; *.img; *.iso; *.lcd; *.mdf; *.mds; *.ncd; *.nrg; *.p01; *.pdi; *.pxi; *.vcd
"C:\Program Files\PowerISO\piso.exe" mount "[RomPath]\[RomFile]" D:
"C:\Program Files\PowerISO\piso.exe" unmount D:

Usage: piso <command> [parameters] [-switches]

<Commands>

listvd
List all virtual drives created by PowerISO

setvdnum <n>
Set number of virtual drives. n is between 0 and 8.
Example: Set number of virtual drives to 1.
piso setvdnum 1

mount <file name> <drive>
Mount image file to virtual drive.
Example: Mount d:\test.iso to drive F:
piso mount d:\test.iso F:

unmount <drive|all>
Unmount image file.
Example: unmount drive F:
piso unmount F:
Example: unmount all drives.
piso unmount all

list <image file> <directory>
List files and directorys in image file.
Example: List all files and directorys in root direcory of d:\test.iso recursively.
piso list d:\test.iso / -r

extract <image file> <dir/file name>
Extract file/directory from image file.
Example: Extract all files and directorys in root direcory of d:\test.iso to d:\temp recursively.
piso extract d:\test.iso / -od d:\temp

convert <image file>
Convert image file to other format.
Example: Convert d:\test.iso to d:\test.daa
piso convert d:\test.iso -o d:\test.daa -ot daa

create
Create image file from files or folders.
Example: Create d:\test.iso from d:\test and d:\test.zip.
piso create -o d:\test.iso -add d:\test / -add d:\test.zip /

<Switches>

-r
List directory recursively.

-o
Specify output image file name.

-od
Specify output folder.

-ot <iso|daa|bin>
Specify output image file type. If not specified, the image type will be determined by file name suffix.

-add <local dir/file name> <dir in image file>
Add local file or directory to image file.

-volsize <n>
Split output image file to multiple volumes, and set volume size to <n>. Example: -volsize 100M

-setpassword <password>
Set password for output image file.
Example:-setpassword 12345678

Virtual CD ShareWare
Supports: *.b5i; *.bin; *.bwi; *.c2d; *.img; *.iso; *.mdf; *.nrg; *.vc4; *.xmf
"C:\Program Files\Virtual CD v8\System\vc8cmd.exe" /i "[RomPath]\[RomFile]" D:
"C:\Program Files\Virtual CD v8\System\vc8cmd.exe" /e D:

<VCD file (.vc8,.vc6,.vc4...)>
Loads the specified VCD image file in the default drive.

/i[nsert]<VCD file> <drive>:
Loads the specified VCD image file in the specified drive.

/i[nsert] <description> <drive>:
Loads the image file with this description in the drive specified.

/e[ject] <drive>:
Ejects the image file from the specified drive.

/x <program>
Executes the specified program.

/w <working directory>
Sets the specified directory as working directory.

/v
Displays detailed messages.

/q
Suppresses all messages

Virtual CloneDrive FreeWare
"C:\Program Files\Elaborate Bytes\VirtualCloneDrive\VCDMount.exe" /d=0 "[RomPath]\[RomFile]"
"C:\Program Files\Elaborate Bytes\VirtualCloneDrive\VCDMount.exe" /u

/u
Unmount image file.

/d=1 <filename>
Mount image file to virtual drive.

Image File Formats
*.000 = Virtual CD
*.ashdisc = Ashampoo
*.b5i = BlindWrite 5
*.b5t = BlindWrite 5
*.bin = CDRWin
*.bwi = BlindWrite
*.bws = BlindWrite
*.bwt = BlindWrite
*.c2d = WinOnCD
*.ccd = CloneCD
*.cdi = DiscJuggler
*.cif = Easy CD/DVD Creator
*.cue = CDRWin
*.daa = Direct Access Archive
*.dao = Duplicator
*.fcd = Virtual CD-ROM
*.gi = RecordNow
*.ima = CloneCD
*.img = CloneCD
*.iso = Standard ISO
*.lcd = CDSpace
*.md1 = Gear
*.mdf = Alcohol 120%
*.mds = Media Descriptor
*.ncd = NTI CD-Maker
*.nrg = Nero
*.nri = Nero
*.p01 = Gear
*.pdi = Instant CD/DVD
*.pxi = PlexTools
*.sub = CloneCD
*.tao = Duplicator
*.vaporcd = Noum Vapor CDROM
*.vc4 = Virtual CD
*.vcd = Virtual Drive
*.vdi = Virtuo CD Manager
*.xa = Gear
*.xmf = CDRWin

Notes:
Its important to disable any sort of AutoPlay\AutoStart feature for any drive used for emulation. I highly suggest using TweakUI to disable Windows own AutoPlay feature.

Directions:
Once you've installed TweakUI, you'll find a lot of options in it. For our current problem, in TweakUI expand My Computer, and then AutoPlay. Click on Drives, and uncheck the drive letter that you no longer want to AutoPlay. Click on Apply, and that's it. No more "what would you like me to do" dialogs.

[Space Fractal]

I known Gens supporting ISO directly, but I do not known about others emulators. So you should convert to ISO format for best performent with a emulator without using a Virtual Drive application.

It some time ago I tested last, but remember the games I tried did got running in that emulators pretty good, without a virtual drive application.