An interesting encrypted but not compressed MIDI karaoke format (~5000-30000 songs on the disk)

[korgm3]

Hi guys,

I have two MIDI karaoke discs in an interesting format not previously discussed here. One disk is Chinese with ~27000 songs, another one is English/Russian with ~5000 songs. Disks exist in the same format for Vietnamase, Indonesian, Spanish, English, Korean, and Japanese - each with thousands songs.  
An interesting feature is that these midi files are not compressed nor bundled together into one huge binary. They do seem to be encrypted though, as files have extension .MDN. I couldn't seen any of the usual Mthd, Mtrk, etc. when opening them in binary editor.
They can be read by Rolsen DVD players (korean) and apparently by older CAVS players.

Here's the directory listing on one of the disks, the other one is identical:

1. D:/Karaoke

Fanfare (Folder)
CIS (Folder)
Font (Folder)
Info (Folder)
DISCID.DAT (1 kb)
NP01.DAT (1 kb)

2. D:/Karaoke/Fanfare

NFAN1.MDN --->> NFAN6.MDN

(2 - 6 kb)

3. D:/Karaoke/CIS
CIS00001.MDN -->> CIS04489.MDN

(~10-150 kb each)

I believe that these are encrypted midi songs. Not compressed, though as I can compress .MDN files with WinZip...

4. D:/Karaoke/Font

FONT0005.DAT 22mb
FONX0005.DAT 15mb
FONT0006.DAT 22mb

5. D:/Karaoke/Info

DSONGHDR.DB (191kb)
SINGER.GLI (1kb)
SORTGASU.LST(18kb)
SORTNAME.LST(18kb)

6. D:/Video_TS

I'm attaching a few .MDN files and all files from the Info folder hoping that we could decrypt these. Man, we'd have ~50000 high quality midis then! I will share all the files if we are successful. I'm not a programmer, so looking for your help guys. Bigboss97, anyone else who can help?


From the Info folder:
DSONGHDR.DB       
SINGER.GLI
SORTGASU.LST
SORTNAME.LST

A few songs:
#4358 - ABBA - The winner takes it all
CI04358.MDN

#4215 - Celine Dion - The power of love
CI04215.MDN

#3886 - Sting - Every breath you take
CI03886.MDN

[bigboss97]

korgm3 wrote

They can be read by Rolsen DVD players (korean) and apparently by older CAVS players.

Does it play not just video, but also karaoke with all the menu functions?
Do you also have the player for those disks?

[korgm3]

Bigboss, thanks for showing up in the topic!

I don't have the player anymore. Hence the wish to decode those midis :)

As to your question, yes, there are video files on the disk, these are played in the background.

I don't know how hard it is going to be to decrypt this format as we don't have any leads except the encrypted files themselves. Unless of course the encryption algorithm is something more-or-less easy.

But wait! (as they say in commercials, LOL). I guess I have something more interesting and something that will be much easier to decode! There have been topics on this board about the so-called PLF midi karaoke disc format. Well, I happen to have a karaoke player (Vsonic KMD-221) that came with 3 midi disks in this 'PLF' format. There are about 130000 songs in like 10 languages on these three disks.

I did quite a lot of googling about PLF karaoke format, took apart my karaoke palyer :), and discovered that thare is a decoder board inside it based on Sunplus 8020r processor. Some more googling and I found the original source code of the firmware for 8020 decoder family. It's looks like it's written in C. I'm no programmer, but doing some string searches in the archive with the source code I found chunks of code that deal with reading midi disks in the 'PLF' format. It's all contained in a few files in the source code.

I'm hoping that for someone who understands C it should be (relatively) easy to understand this code and write a program based on it to read midi disks in PLF format and extract midi and lyrics. I have 3 disks in this format and there are about 130000 songs in ~10 languages! I'm going to create a separate topic on this. For anyone who's interested I'll upload the contents of the DVDs and the source code of the decoder.

[bigboss97]

korgm3 wrote

I did quite a lot of googling about PLF karaoke format, took apart my karaoke palyer :), and discovered that thare is a decoder board inside it based on Sunplus 8020r processor. Some more googling and I found the original source code of the firmware for 8020 decoder family. It's looks like it's written in C. I'm no programmer, but doing some string searches in the archive with the source code I found chunks of code that deal with reading midi disks in the 'PLF' format. It's all contained in a few files in the source code.

Firmware source code in public?

korgm3 wrote

I'm going to create a separate topic on this. For anyone who's interested I'll upload the contents of the DVDs and the source code of the decoder.

Can't wait.

[korgm3]

Yes, I was surprised to find firmware sorce too. Hoping that someone had already figured the format I googled two file names ("MEGMID AND MEGVOL") that are on all three midi disks and the very first result pointed to a .h file containing references to these filenames. This file was part of an archive that contained full source of the firmware for Sunplus 8202a board.

I was sleepy yesterday when writing my reply to you, it's 8202 board that I have inside my player, not 8020. This one, to be precise:

http://www.szwld.com/cp/html/?20.html

I couldn't download full firmware source from the first link as that website is for programmers and you have to upload something before you download, but I later found source of the firmware for 8202s and 8202d processors on a Yahoo group Sunplus_Firmware:

http://tech.groups.yahoo.com/group/Sunplus_Firmware/

It looks like subroutines for reading PLF midi disks are same between different incarnations of 8202 family Sunplus processors like 8202a, 8202d, 8202s.

Anyways, I'll create a new topic, and I hope with the experience of people on this board we can figure it all out together. It would be great if we could extract all those 130000 midis, if possible lyrics as well. Myself, I would like to be able to play them on my PC and my Yamaha PSR music keyboard.

[bigboss97]

A while ago there was someone started a discussion about Arirang disk. At the end he said he used a hardware solution. I wasn't sure what he meant. Maybe that's it.

korgm3 wrote

I couldn't download full firmware source from the first link as that website is for programmers and you have to upload something before you download, but I later found source of the firmware for 8202s and 8202d processors on a Yahoo group Sunplus_Firmware:

Please post as much details as you can, so that other won't repeat your finding.

korgm3 wrote

Myself, I would like to be able to play them on my PC and my Yamaha PSR music keyboard.

That's definitely a goal. Currently I play my California disk to:  :-)
https://www.facebook.com/photo.php?fbid=343877635639719&set=o.321428581959&type=3&theater

[bigboss97]

korgm3 wrote

http://www.szwld.com/cp/html/?20.html

I couldn't download full firmware source from the first link as that website is for programmers and you have to upload something before you download, but I later found source of the firmware for 8202s and 8202d processors on a Yahoo group Sunplus_Firmware:

Which link are you referring to? I couldn't see any download link in above site.
I know, I should wait until you put everything together  :-)  But I thought I better have a look before things disappear. Nowadays you never know. Everything happens so quickly on net.

[korgm3]

That is the manufacturer's website, they wouldn't publish source code of the firmware :)

I downloaded firmware from the Files section of http://tech.groups.yahoo.com/group/Sunplus_Firmware/

Don't worry, I will upload everything. It's going to take some time as each DVD is 5-8 gb in size. Which site do you think would be a good place to upload to? I was thinking about 4shared.