On Wed, Jul 8, 2009 at 6:52 AM, Kostya<[email protected]> wrote: > On Wed, Jul 08, 2009 at 12:25:09PM +0200, Diego Biurrun wrote: >> On Mon, Jul 06, 2009 at 10:38:55PM -0400, Alex Converse wrote: >> > On Mon, Jul 6, 2009 at 9:28 PM, Diego Biurrun<[email protected]> wrote: >> > > On Mon, Jul 06, 2009 at 09:14:00PM -0400, Alex Converse wrote: >> > >> I'd like to take a minute to discuss the status of the AAC encoder and >> > >> where it is going. >> > >> >> > >> In SoC svn: >> > >> --Lacks multichannel support >> > >> --Lacks SBR >> > > >> > > These are likely low priority. >> > >> > All the other AAC encoders out there worth their salt support these. >> > It's 2009, SBR is no longer a fringe extension to AAC that major >> > implementations don't support. Microsoft and Apple have both moved to >> > supporting HE-AAC. 14496-3:2009 will include the HE-AAC profile in the >> > main body (not an amendment). SBR is absolutely necessary to be >> > competitive at low bitrates. >> >> I don't doubt that SBR is good, but getting a functioning basic encoder >> that produces a simple but valid bitstream is more important. SBR >> support can (and will have to) come after that. > > It would be very convenient to get it in decoder first too. > >> > >> --Maximum frame size enforcement >> > > >> > > Could you try to get this merged next? >> > >> > It depends on the rate control stuff. >> >> Then try to get the rate control stuff merged first :) > > That's another tricky stuff but we'll get it eventually. > >> > >> To be frank, at this point it seems like it might be prudent for me to >> > >> stop working on this >> > > >> > > Uh, why? >> > >> > Getting faac free (by dropping long forgotten profiles and >> > reimplementing things from spec), seem like less effort than getting >> > FFmpeg to faac quality (running around trying to fix bugs in someone >> > else's codebase). Building on 26.410 v8.0.0 is attractive because it >> > is already better quality than ffmpeg and faac and includes a working >> > SBR implementation which would require tons of work to add to ffmpeg >> > or faac. >> >> What is "26.410 v8.0.0", where can I find it and how is it licensed? > > 3GPP TS 26.410 aka AAC encoder floating point code. Guess license by > yourself ;) >
All of the encoder source lacks copyright notices/licensing terms >From the Documentation: No part may be reproduced except as authorized by written permission. The copyright and the foregoing restriction extend to reproduction in all media. © 2008, 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TTA, TTC). All rights reserved. >From the build system: # Copyright (c) Coding Technologies 2003 # All Rights Reserved > [...] >> >> > I'm not the only one who's wondered if FFmpeg is really the best place >> > to implement a high quality encoder. FFmpeg lacks a VC-1 encoder, an >> > H.264 encoder, and an MP3 encoder. x264 is developed outside of FFmpeg >> > despite sharing some code. Aften and Flake (that PARCOR routine is >> > actually from Flake) are developed outside of FFmpeg and periodically >> > have features backported. AAC itself is older than FFmpeg (not some >> > johnny-come-lately format) and we still lack a working encoder for it. >> >> Without a doubt, encoders are not FFmpeg's main strength. That does not >> mean we should not attempt to change this. > > Err, have you ever heard of MN-backed MPEG-4 ASP and H.26[1-3] encoders? > Too bad everybody wants that H.264+AAC. > >> Not having an encoder or even a decoder for certain formats often has >> historic reasons. Whenever external libraries of good enough or better >> quality have been available, motivation to write equivalents in FFmpeg >> has been low... > > Reminds me of AMR. > >> Diego >> >> P.S.: This should really be discussed on ffmpeg-devel... > _______________________________________________ > FFmpeg-soc mailing list > [email protected] > https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-soc > _______________________________________________ FFmpeg-soc mailing list [email protected] https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-soc
