Xiph.Org, bungwe lodzipereka pakupanga makanema aulere ndi ma codec aulere, adapereka ma codec omvera a Opus 1.4.0, omwe amapereka ma encoding apamwamba kwambiri komanso latency yocheperako pamakanema apamwamba kwambiri komanso kuphatikizika kwa mawu mu bandwidth. -Kugwiritsa ntchito kwa VoIP koletsedwa Kukhazikitsa kwa encoder ndi decoder kumakhala ndi chilolezo pansi pa layisensi ya BSD. Mafotokozedwe athunthu amtundu wa Opus akupezeka pagulu, aulere, ndikuvomerezedwa ngati mulingo wapaintaneti (RFC 6716).
Codec idapangidwa pophatikiza matekinoloje apamwamba kwambiri kuchokera ku codec ya CELT yopangidwa ndi Xiph.org ndi SILK codec yotsegulidwa ndi Skype. Kuphatikiza pa Skype ndi Xiph.Org, makampani monga Mozilla, Octasic, Broadcom ndi Google nawonso adagwira nawo ntchito yopanga Opus. Ma Patent omwe akukhudzidwa ndi Opus amaperekedwa ndi makampani omwe akukhudzidwa ndi chitukuko kuti agwiritse ntchito mopanda malire popanda kulipira chindapusa. Ufulu wanzeru zonse zokhudzana ndi Opus ndi zilolezo za patent zimaperekedwa kwa mapulogalamu ndi zinthu zogwiritsa ntchito Opus, popanda kufunika kowonjezera chilolezo. Palibe zoletsa pakukula kwa ntchito komanso kupanga njira zina za gulu lachitatu. Komabe, maufulu onse operekedwa amachotsedwa pakakhala milandu yokhudza patent yomwe ikukhudzana ndiukadaulo wa Opus motsutsana ndi aliyense wogwiritsa ntchito Opus.
Opus imakhala ndi ma encoding apamwamba komanso latency yotsika pamawu omvera komanso kuphatikizika kwamawu pama foni a VoIP omwe ali ndi bandwidth. M'mbuyomu, Opus idazindikirika ngati codec yabwino kwambiri mukamagwiritsa ntchito 64Kbit bitrate (Opus idapambana opikisana nawo monga Apple HE-AAC, Nero HE-AAC, Vorbis ndi AAC LC). Zogulitsa zomwe zimathandizira Opus kunja kwa bokosi zikuphatikiza msakatuli wa Firefox, chimango cha GStreamer, ndi phukusi la FFmpeg.
Zofunikira zazikulu za Opus:
- Bitrate kuchokera ku 5 mpaka 510 Kbit / s;
- Zitsanzo pafupipafupi kuchokera 8 mpaka 48KHz;
- Kutalika kwa chimango kuchokera ku 2.5 mpaka 120 milliseconds;
- Imathandizira pafupipafupi (CBR) ndi ma bitrate osinthika (VBR);
- Imathandiza narrowband ndi wideband audio;
- Thandizo la mawu ndi nyimbo;
- Thandizani stereo ndi mono;
- Imathandizira kusintha kwamphamvu kwa bitrate, bandwidth ndi kukula kwa chimango;
- Kuthekera kobwezeretsanso mawu omvera ngati chimango chitayika (PLC);
- Imathandizira mpaka mayendedwe 255 (mafelemu amitundu yambiri)
- Kupezeka kwa zochitika pogwiritsa ntchito masamu oyandama komanso osakhazikika.
Zatsopano zazikulu mu Opus 1.4:
- Ma encoding magawo akonzedwa, omwe cholinga chake ndi kukulitsa zizindikiro zamtundu wa mawu pamene FEC (Forward Error Correction) imayatsidwa kubwezeretsa mapaketi owonongeka kapena otayika pa bitrate kuchokera ku 16 mpaka 24kbs (LBRR, Low Bit-Rate Redundancy).
- Onjezani OPUS_SET_INBAND_FEC njira kuti muthe kuwongolera zolakwika za FEC, koma popanda kukakamiza SILK mode (FEC sidzagwiritsidwa ntchito mu CELT mode).
- Kupititsa patsogolo njira ya DTX (Discontinuous Transmission), yomwe imatsimikizira kuti magalimoto amaimitsidwa pamene palibe phokoso.
- Thandizo lowonjezera pamakina omanga a Meson ndikuthandizira bwino pakumanga pogwiritsa ntchito CMake.
- Makina oyesera a "Real-Time Packet Loss Concealment" yawonjezedwa kuti abwezeretse zidutswa zamalankhulidwe zomwe zidatayika chifukwa cha kutayika kwa paketi, pogwiritsa ntchito makina ophunzirira makina.
- Anawonjezera kuyeserera kwa makina a "deep redundancy", omwe amagwiritsa ntchito makina ophunzirira makina kuti apititse patsogolo mphamvu zobwezeretsanso mawu pambuyo potayika paketi.
Source: opennet.ru