Maybe the one that I don't understand is that doozie, but can anyone say for sure?
this is US patents. is there any patents for MP3 in other countries?
Quote from: bawjaws on 16 March, 2012, 11:39:33 AMMaybe the one that I don't understand is that doozie, but can anyone say for sure?I think claims 1-3 are basically for the quantization and scale factor system used in mp3. I don't think you could work around that while retaining compatibility with the standard.
Graf, if it's not too much of trouble could you create a list of AAC related patents as well? EDIT: just figured out that you provide sources in your summary.
I've made a LAME build which avoids USPTO 5559834. It's usable, though there are severe quality impacts. Still, if you want to make a patent-free MP3 encoder and are willing to accept severe quality compromises, it seems this is possible already today.
That's very cool. Is there a public source repository or even just some mp3 samples of its output available?
I wonder if sounding a bit 'odd' would be helpful in avoiding patent troubles since you'd be doing something tangibly different, whereas there's probably workarounds that are technically different but legally murky just because the output sounds the same (or even better) than "standard" mp3.
I have no clue what 'or even better than "standard" mp3' is supposed to mean. It's possible to design a codec that is free of MP3 patents and outperforms it. Vorbis and Opus do this.
So it was a comment about the possibility of avoiding actual, practical legal risk by doing something that makes no sense at all from either a technical perspective or a strictly theoretical legal perspective.
seems more "believable" than saying "these codec patents that people charge millions for aren't really that essential
look we've built an encoder even better than what is described in the patents without even using the techniques they describe
Quote from: bawjaws on 20 March, 2012, 05:03:16 PMThat's very cool. Is there a public source repository or even just some mp3 samples of its output available?Take the latest LAME source and edit newmdct.c where it says "Perform aliasing reduction butterfly". The code suggests that running in all-short-blocks mode also avoids the patent.
when I comment out the body of that function
or pass --allshort
I don't hear any obvious difference in the output when I use lame with otherwise default settings on the soundtrack from the Sintel trailer provided in flac by Xiph. In fact from a very quick and unscientific test I can't tell the original WAV apart from any of them.
The --allshort one is noticeably larger when I pass -V9 but I was expecting a more fundamental problem, one that couldn't be overcome by turning up the bitrate.
Avoiding 5559834 by commenting out the butterfly code is not just "odd" or "strange". The aliasing is really, really bad.
I'm trying to get a handle on some objective measure of "really, really bad". I assume those are at the same bitrate. How much would you have to increase the bitrate on the hacked version for it to match (visually and/or audibly) the patented version? Is it even possible? How does that bitrate increase generalize to other types of audio such as speech or popular music?