Well, after re-reading docs, by default INBandFEC should be assumed to be 1 by the encoder :). I'll fix that too. On 30/05/2012 10:41, Oleg Lutsenko wrote: > Regis, > > The problem is that I need to work with SILK, so I can not move to > Opus. Do you have any idea how to get access to the frames from jbframes? > > Regarding note 1, I think that your implemenatation doesn't need any > changes, because it looks like it already notifies remote side that > you do not have support of FEC: > > /*SKP_int32 INBandFEC_enabled = 0 ... > ...*/ > /* silk->enc.useInBandFEC = INBandFEC_enabled; > */ > Regards, > Oleg Lutsenko > > On Friday, May 25, 2012 at 9:20 PM, R?gis Montoya wrote: > >> Ok, >> >> You're right, in fact what I use only enable the PLC feature of SILK >> that does extrapolation with SKP_Silk_PLC. That's why I observed that >> PLC is done. >> >> So the PLC feature is enabled, but you're right the FEC data is not >> used. I just had a closer look to opus source code and they slightly >> modified silk so that SILK is clever and does the FEC decode by itself >> managing buffers. >> >> Maybe we could get inspired of what is done in opus, but would mean >> adding extra complexity to SILK decode process by buffering things. >> Another solution would be to get the next frames from pjmedia jitter >> buffer; but AFAIK, there is no clean way to get the jb frames from a >> codec implementation, but I may be wrong. >> >> Side note 1 : with your remark in mind, I should fix my current >> implementation to announce remote side that I don't use FEC info for >> SILK codec. It will reduce packet size, since for now it's not >> implemented, not necessary to ask remote side to send FEC info :). >> >> Side note 2 : opus is definitely better and easier to use. If you have >> no constraint on the codec choice, you should maybe have a look on the >> opus project (it includes silk and use it for low bandwidth usage >> cases). And even if still not finalized it sounds really promising :). >> >> Regards, >> R?gis >> >> On 25/05/2012 17:06, Oleg Lutsenko wrote: >>> Regis, >>> >>> Correct, I am using your implementation, good job! Thank you! >>> >>> But as I understand from SILK documentation (SILK SDK API pdf >>> document), you should call this function >>> >>> SKP_Silk_SDK_search_for_LBRR >>> >>> to retrive lost frame from next (n+1 and n+2) frames. And in your >>> implementation you never call this function. >>> >>> Regards, >>> Oleg Lutsenko >>> >>> >>> On May 25, 2012, at 4:51 PM, R?gis Montoya wrote: >>> >>>> Oleg, >>>> >>>> I guess that you use my implementation >>>> (http://code.google.com/p/csipsimple/source/browse/trunk/CSipSimple/jni/silk/pj_sources/silk.c) >>>> of silk codec. >>>> >>>> As far as I understood from silk codec api, the storage of previous >>>> frames is done by SILK itself. So the implementation I did is >>>> already valid to use FEC feature of SILK. >>>> And for the few tests I did with SILK with my implementation it's >>>> already capable to retrieve lost frames. >>>> >>>> I could mistake however since I didn't spent a lot of time on the >>>> SILK implementation. But my guess are pretty confirmed by the Opus >>>> implementation I did later (opus is based on SILK + CELT). >>>> >>>> So normally, you have just nothing to do if you want to use FEC >>>> with pjsip + my codec implementation. >>>> >>>> Regards, >>>> R?gis >>>> >>>> >>>> Le 25 mai 2012 16:31, "Oleg Lutsenko" <oleg.lutsenko at googlemail.com >>>> <mailto:oleg.lutsenko at googlemail.com>> a ?crit : >>>> Hi guys, >>>> >>>> I am going to use nice FEC (Forward Error Correction) feature of >>>> SILK codec, to recover lost frames. To use this feature I need to >>>> have access to the next two frames after the lost one. This two >>>> frames include redundant information about previous frame, so, >>>> potentially, its possible to recover the lost frame. >>>> >>>> pjmedia_codec_op struct has recover function which I need to implement: >>>> >>>> pj_status_t(* pjmedia_codec_op::recover)(pjmedia_codec *codec, >>>> unsigned out_size, struct pjmedia_frame *output) >>>> >>>> The problem I have right now, is that I have no idea how to get any >>>> frame around the lost one. Is there any way how to get specific >>>> frame in a stream? >>>> >>>> Regards, >>>> Oleg Lutsenko >>>> _______________________________________________ >>>> Visit our blog: http://blog.pjsip.org >>>> >>>> pjsip mailing list >>>> pjsip at lists.pjsip.org <mailto:pjsip at lists.pjsip.org> >>>> http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org >>>> >>>> _______________________________________________ >>>> Visit our blog: http://blog.pjsip.org >>>> >>>> pjsip mailing list >>>> pjsip at lists.pjsip.org <mailto:pjsip at lists.pjsip.org> >>>> http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org >>> >>> _______________________________________________ >>> Visit our blog: http://blog.pjsip.org >>> >>> pjsip mailing list >>> pjsip at lists.pjsip.org <mailto:pjsip at lists.pjsip.org> >>> http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org > > > > _______________________________________________ > Visit our blog: http://blog.pjsip.org > > pjsip mailing list > pjsip at lists.pjsip.org > http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org -------------- next part -------------- An HTML attachment was scrubbed... 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