How legal is ac3enc.dll

[Acaila]

Aren't we supposed to pay Dolby to encode audio into AC3 or something? How come you can give this tool for free (not that I mind! :D)?

[MaTTeR]

Sort of what I was thinking Acaila.

@DSPguru
This program is legitimate? Would like to know before I put it on my company laptop here...

[Doom9]

it's based on ac3enc which is part of the ffmpeg project.. so the dll is as legitimate as ac3enc. We'd also have to pay licensing fees for lame and xvid.. but as we're all only using it for educational purposes it's too costly for the license holders to do anything about the situation.

[MaTTeR]

Educational indeed...that's all this poor 700Mhz laptop would allow;)

Edit- Anyone care to post results compared to SoftEncode?

[MaTTeR]

canadian_fbi,

I'm in the same boat as you, currently stuck in New York with my little ol laptop. I get home in 6 weeks and will do some serious listing tests.

In the meantime, if you beat me to it, please post your thoughts;)

@Dg
canadian_fbi would be a canidate for you.

[The Belgain]

I transcoded a 448 kbit 5.1 AC3 down to a 256 5.1 Ac3 using AC3 Machine, and the channel mapping is messed up:

I did it both using the default settings and usign the settings recommended by doom9 (all the azid downmix options unchecked).

I'm playing the sound back on a 2 speaker system (through an analog connetion) and the dialog is almost silent whereas the background sound is much louder). It seems like it might have dropped the centre channel maybe?

It's hard to judge the quality, seeing as most of the sound is missing, but it sounds a little hissy (though that could be because it now needs to be played at high volume).

I'm now trying the same thing using soft encode (horribly slow!) to see how that works.

[DSPguru]

please, always, attach your logfiles.

also, for testing, you can use the testfiles i've made :
http://dspguru.notrace.dk/dgtestfiles.zip

[Tonkutsche]

Hello!

Ich have a easy question: How legal is AC3enc.dll?

Cheers

Florian

[jorel]

Originally posted by Tonkutsche
Hello!

Ich have a easy question: How legal is AC3enc.dll?

Cheers

Florian

:o
i really don't know but (i'm thinking)

...if is ilegal,Doom9,DSPguru and moderatores
had "shoot out" ac3enc.dll from here a long time ago!

this forum don't support(and don't need)ilegals!
:)

[Doom9]

As with other open source projects implementing a patented standard (faac, faad, bbmpeg, ffmpeg, xvid, etc.) the legality depends on the use case. Those projects are for educational use only, and as long as you use them accordingly you don't have a problem. However, if you start using them in a commercial environment (for instance use xvid encoded videos on promotional CDs), then you have to get a license from the proper authority. So, if you plan on using ac3enc for your commercial DVD projects, you must contact Dolby and get a license.