Open Source Smacker Decoder

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slake_jones
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Open Source Smacker Decoder

Post by slake_jones »

Just wanted to ask the developers if they are aware of a new open source (GPL) Smacker decoder being produced.

Currently no files have been released but it might be worth keeping an eye on the project.

Its called libsmack and can be found at http://sourceforge.net/projects/libsmack

I stumbled apon it when I was looking for some libraries for a project i'm working on.

I hope this might be useful as support for smacker files might be possible for games like The Feeble Files.

Tom.
fingolfin
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Re: Open Source Smacker Decoder

Post by fingolfin »

slake_jones wrote:Just wanted to ask the developers if they are aware of a new open source (GPL) Smacker decoder being produced.
Use the handy but apparently too-hidden (and hence rarely if ever used) "Search" feature of this forum, and you can easily find out the answer to your question, as well as our position regarding these smacker decoders :-)
slake_jones
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Post by slake_jones »

Sorry, should have searched first :oops: However I think it is a different library than the one mentioned in the other forums. More specifically I found info from FFMPG and it mentions this code is writen in C#.

The libsmack library I stumbled upon is apparently written for all POSIX systems. I would guess that its written in C/C++ so it might be easyer to implement.

Once again sorry for the repeated thread.
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sev
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Post by sev »

Well, it may really happen that that's one of ffmpeg folks, since they were planning to create a standalone smacker library for us, so we will not have to link against full-blown ffmpeg. But this project not just did not release any files, it even doesn't have any content in CVS and still is on Planning stage. So it could be a hoax.


Eugene
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eriktorbjorn
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Post by eriktorbjorn »

slake_jones wrote:More specifically I found info from FFMPG and it mentions this code is writen in C#.
I don't know if I misunderstand what you mean, but ffmpeg is written in C, not C#.
slake_jones
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Post by slake_jones »

Oh, it said on this forum http://forum.scummvm.org/viewtopic.php? ... ht=smacker that it was written in C#. I havent looked into it though.
cappuchok
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Post by cappuchok »

There's also the strange issue of Microsoft releasing MechCommander 2 under their Shared Source license (which is approved by OSI as an Open Source license). MechCommander 2 movies are encoded with Bink, and Microsoft claims that the source code package includes "everything needed to compile a fully working copy of the game". This would presumably include the required decoder source and it most certainly includes the movies.

I guess we'll never know whether the release was an unintentional mistake by Microsoft, or endorsed by RAD.

But if it was approved by RAD (and I think we can safely say it would have to be, because Microsoft isn't in the habit of making licensing mistakes like this) I can't see any reason for them to deny people the right to decode even older formats in their non-profit opensource projects.
fingolfin
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Post by fingolfin »

Unfortunately, cappuchok, your logic is flawed and also based on false assumuptions.
cappuchok wrote:There's also the strange issue of Microsoft releasing MechCommander 2 under their Shared Source license (which is approved by OSI as an Open Source license).
It wasn't Microsoft who submitted "the" Shared Source license (in fact there are several different ones) to the OSI, for starters, but somebody else who has a queer sense of humor. Microsoft explicitly stated that they have no plans to submit any of the SSL variants to the OSI, either.

Secondly, if you the Shared Source licenses, in particular the one relevant for MechCommand 2, is not compatible with the GPL.
cappuchok wrote:I guess we'll never know whether the release was an unintentional mistake by Microsoft, or endorsed by RAD.

But if it was approved by RAD (and I think we can safely say it would have to be, because Microsoft isn't in the habit of making licensing mistakes like this)
No dice. As long as they do not explicitly state that they have the right to distribute the code, as long as there are reasons to doubt this, law requires us to assume that this is not legal. Just because Microsoft is big doesn't mean they automatically always do the proper / legal thing, even when they are trying to for a change.
cappuchok wrote:I can't see any reason for them to deny people the right to decode even older formats in their non-profit opensource projects.
Law doesn't work like that: "You gave Cindy a free ice cream -- I don't see any reason then why you wouldn't allow me to take some of the chocolate bars, so I'll just take one" -- nope, that's not a valid conclusion, ask your mum :-).
If you get a license for produce A, then you only got a license for product A, but *not* automatically for product B, even if B is an older predecessor of A.

In particular, them releasing source for Bink under the Shared Source license doesn't mean, for example, that we are allowed to reverse engineer Smacker.

Finally, even if RAD officially released the Smacker source code under the Shared Source license, we couldn't use it, since this license it is deeply incompatible with the GPL.
cappuchok
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Post by cappuchok »

fingolfin wrote:In particular, them releasing source for Bink under the Shared Source license doesn't mean, for example, that we are allowed to reverse engineer Smacker.

Finally, even if RAD officially released the Smacker source code under the Shared Source license, we couldn't use it, since this license it is deeply incompatible with the GPL.
Who said anything about RE:ing? Sorry if my English is a bit rusty. I simply meant that if RAD agreed to Microsoft releasing the Bink source code (which we don't know if they did, obviously) then perhaps in light of that, RAD would perhaps now be more receptive to the idea of letting some open source project take a peek at the Smacker source and create a simple GPL'd decoder (not by RE, rather by rewriting it from scratch). I never suggested that this Microsoft release would make it OK to just RE Smacker without asking RAD for permission.

But yes, I know it was a longshot, and only Microsoft and RAD knows if my guess (not assumptions, as you interpreted them) about their possible agreement was correct. It was simply a funny line of thought, and as such not worthy of any deeper analysis.

I'll shut up now. :)
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