Logitech MSN Webcam Codec Reverse-Engineered

Alexis Boulva writes "Tonight, Ole André Vadla Ravnås of the Farsight project (LGPL), which 'is an audio/video conferencing framework specifically designed for Instant Messengers' for the GNU Linux operating system, finished coding a release candidate of libmimic, 'an open source video encoding/decoding library for Mimic V2.x-encoded content (fourCC: ML20), which is the encoding used by MSN Messenger for webcam conversations.' Ole, on the libmimic site, remarks that 'It should be noted that reverse-engineering for interoperability is 100% legal here in Norway (and in most European countries).' Looks like the Free/Open Source Software movement is very close to closing up one of the most noticeable software gaps remaining from its glorious efforts."

Legality in US?

[caryw]

What is the current status of legality of reverse-engineering of software in the US? I know that hardware reverse-engineering has stood up in court time and time again, but software is a different story. Especially with a powerful plaintiff such as Microsoft.
--
NoVA Underground: Where Northern Virginia comes out to play [novaunderground.com]

Sure, until MSN 7 comes out of beta

[the_unknown_soldier]

Looks like the Free/Open Source Software movement is very close to closing up one of the most noticeable software gaps remaining from its glorious efforts."

That is until MSN 7 includes a new codec or in other ways blocks this implementation

Please Explain The "glorious efforts" uote....

[BRock97]

"Looks like the Free/Open Source Software movement is very close to closing up one of the most noticeable software gaps remaining from its glorious efforts."

Could someone please explain to me what in the hell this line means? It could be that it is only 6:30 in the morning, but the way I read this line, it makes it out that the FOSS is responsible for the causing gap that they just closed. Anyone else? I would have thought Microsoft is responsible, but maybe I am missing something here......

Wait ...

[ggvaidya]

Until MSN changes the protocol again. Timothy's byline is imho the most insightful part of the document: it's an extract from an ancient quote that goes, "DOS isn't done until Lotus won't run". [ref [dgl.com]].

MSN's frequent "we won't let you run messenger because we need to install crucial updates for which you need to be administrator" errors is why I use Yahoo these days, but I can see how the videocam feature would be helpful to people - and how easy it would be for MSN to change it's protocols around.

Of course, GAIM had the same problem with Yahoo messenger, and they just fought them tooth-and-nail. What I'm saying is, unless somebody really puts their muscle behind this, MSN will just keep screwing around with them.

Re:Sure, until MSN 7 comes out of beta

[0x461FAB0BD7D2]

How are they going to block a codec? Perhaps they could fudge the codec a bit, but that would break compatibility with MSN Messenger 6, frustrating their own customers. In any case, the differences in assembly code between MSN7 and MSN6 would be seen quite quickly, and the revelant changes could be made to libmimic.

Perhaps they could ban non-MSN clients, but that hasn't worked too well in the past.

I don't think MSN would try something like that. After all, they're all about interoperability right?

one of the very important stumbling block removed

[krayfx]

i say its most important, because this will help desktop users use the linux box for regular home usage. i used to find this an impediment. being able to use the webcam will help me move to linux completely for communication purposes. this has been the case for many people. for the average home user - not being able to access the webcam is a major impediment, i hope all the open-source communication sfwares, use the same! this will help change the perception for average joes and janes that linux is indeed user friendly and works as well as ms stuff

Re:Reverse Engineered From The Disassembly

[mccalli]

Also, the fact he has a C implementation will hopefully imply portability between architectures, not just OSes.

Linux isn't the only OS without an MSN video client, OS X/PPC could do with one too. As nice as iChat is, unless everyone you know is on the AIM network you're somewhat limited. I understand AIM is the largest IM network in the US, however in the UK I'd (unscientifically) say that title belongs to MSN.

I'm fully aware that having a C implementation doesn't necessarily mean portability (endianess, 64 vs 32 bit etc.), but it certainly helps.

Cheers,
Ian

All professional VTC is open source anyway...???

[J Barnes]

90% of all video conferencing done in the professional world is based on open standards already, H.323 and H.264 are much more viable options then a propriotary microsoft product.

If linux and other GNU/GPL/open source projects are to routinely tout the viability of open source standards, why not simply use the existing and tested open sources already in use in the vast majority of VTC solutions?

Unless it's a bunch of linux users that want to taunt microsoft fans on MSN.

Over reacting?

[Chris Kamel]

Looks like the Free/Open Source Software movement is very close to closing up one of the most noticeable software gaps remaining from its glorious efforts.
Don't u think that's a little over reacting to call a video codec for videoconferencing, one of the most noticeable software gaps?

Re:patents?

[Anonymous Coward]

Er. Hence the storm of european software patents! - they _aren't_ currently enforceable in most european countries, but the patent office has been granting the patents anyway. Right now, mimic or whatever it's called is likely 100% legal in europe.

And just to make another point, to those who say FOSS is "just playing catchup" or "always copying" or whatever: Many early Webcam-style applications were BSD-licensed, things like VIC/RAT from the MBONE suite. If it weren't for the installed base of proprietary users, this package would be unnecessary. This is why Microsoft is usually careful not to care too much about "piracy" (and why you shouldn't "pirate" software even if you disagree with copyright...): network effects which dominate the computing market establish lock-in of their proprietary tools.

Re:Reverse Engineered From The Disassembly

[FireFury03]

I call troll...

A less trivial (and possibly more legal) undertaking would have been to code a new framework from scratch

1. There is no legal problem here - it's completely legal to reverse engineer for interoperability.
2. How exactly is your "new framework" going to interact with existing (closed) systems? Or are you expecting the likes of Microsoft to implement a new open protocol so they can interact with the FOSS community?

we complain that MS "embraces and extends" all the time -- how is this any different?

Microsoft does "embrace and extend" on well defined open protocols and screws everyone over because of their market position (which basically forces everyone else to adopt their extensions). This is simply "embracing" (not extending) a propriatory system so we can interoperate with it - no protocols are being broken here.

I much prefer *actual* open source projects. Not open source derived from disassembly of closed source.

Like it or not, when interacting with propriatory systems you have to reverse engineer them because the propriators are sure as hell not going to give you the specs. The same is true of hardware drivers, etc. (an aweful lot of the hardware drivers in Linux were reverse engineered by looking at how the Windows drivers interacted with the hardware). How would you suggest doing it?

Economic Realititties

[__aagujc9792]

100% legal in Norway?

We're obviously going to have to nip this terrorism in the bud. Actually, kudos to our new Norwegian overlords...

In the unintended consequences of moronic special interest legislation department, is this the first tech breakthrough we can point at and say "Congrats DMCA, you have definitively moved progress out of the US!"?

--
OP
I had a .sig somwhere

Re:Legality in US?

[northcat]

This was done in Norway. It has nothing to do with USA. Your question is as relevant here as asking how legal this is in any other country of the world. Why USA?

Re:Why not use ichat/AIM's video protocol?

[Compile 'em all]

>Why not use ichat/AIMs video protocol. It's a >fully open standard,
>described completely on Apple's developer site. >All there ready to go.

Well, It is not about chasing Windows.
Love it or not, MS has 90% of the market and if they didn't decide to use Open standards (ichat/AIMs, Jabber)
then the only way to communicate with those 90% is reverse-engineering MS stuff.

Re:Just how many video codecs do we need?

[lurch_mojoff]

That said, this is NOT The right to go about this (disassemblying closed source, creating open source from it). It's the same shit DivX got in trouble with early on, and they're lucky to have survived. I give much more praise to guys who can write this stuff totally from scratch.

Not to troll or anything, but just how can one write from scratch something, he doesn't have knowledge of? Consult Miss Cleo? Do you really think if there was a detilled how_to_implement_mimic guide, this guy, Ole André Vadla Ravnås, would go to such extremes as to ponder over a buch of Assembly code and try to create a working C program out of it?! Such a feat is worth the praise.

Re:software gaps?

[Anonymous Coward]

are you on drugs?

linux right now supports MORE hardware out of the box than Windows XP.

yup, you heard me. if I install mandrake 10.1 it's ready to go. windows xp I have to download drivers for the devices... oh and that scanner, where is that scanner's driver...

linux just works, quit your blatent lying.

Re:Reverse Engineered From The Disassembly

[1ucius]

There might be a legal issue if he disassembled the code...because most license agreements explicitly forbid disassembly, a court may say he used improper means to get the necessary information. That is, even though reverse engineering is legal, you can't violate other obligations. A reverse engineering effort that relied on 'cleverly inspecting packets' would be much better legal ground.

Re:Legality in US?

[Duckman5]

This quetion is very relevant. Perhaps some of us here in the US might be interested in using this and the vast majority of slashdot readership is located in the US [slashdot.org]? Just because something was created in a country where it was legal does not mean that it can be used in a country where it is not legal. I mean, we've all seen how well DeCSS went over here in the US.