Codec ndilo ndondomeko yeniyeni (Zolondola zimalola kukhala zosavuta - pulogalamu!), Nthawi yambiri yoikidwa ngati pulogalamu pa seva kapena mkati mwa hardware ( ATA , IP Phone etc.), yomwe imagwiritsidwa ntchito kutembenuza Mawu (pa nkhani ya VoIP) amawunikira mu deta yolongosola kuti azifalitsidwa pa intaneti kapena makanema aliwonse pa pulogalamu ya VoIP.
Mawu akuti codec amachokera ku mawu omwe amalembedwa ndi mawu osungira mawu kapena a compressor-decompressor. Codecs mwachizoloŵezi amapindula ntchito zitatu zotsatirazi (zochepa kwambiri zomwe zimatha):
- Kulemba - kutanthauzira
- Kuponderezana - kusokonezeka
- Kusindikiza - Decryption
Kulemba - kutanthauzira
Mukamayankhula pafoni ya PSTN, mawu anu amatengedwa m'njira ya analoji pamzere pafoni. Koma ndi VoIP, mawu anu amasandulika zizindikiro zamagetsi. Kutembenuka kumeneku kumatchedwa kuti encoding, ndipo kumapezeka ndi codec. Pamene mawu opindulitsa amafikira komwe akupita, amayenera kubwezeretsedwanso kumalo ake oyambirira a analog kuti mlembi wina amve ndikumvetsetsa.
Kuponderezana - kusokonezeka
Bandwidth ndi chosowa chochepa. Choncho, ngati deta yotumizidwa imakhala yopepuka, mutha kutumiza zambiri mu nthawi yambiri, motero kusintha bwino ntchito. Kuti mawu opangidwirawo asapangidwe kwambiri, amavomerezedwa. Kupanikiza ndi njira yovuta yomwe deta yomweyi imasungidwa koma kugwiritsira ntchito malo ochepa (digito bits). Panthawi ya kuponderezana, deta imangokhala ndi mapangidwe (pakiti) yoyenera kugwirizanitsa. Deta yolemetsedwera imatumizidwa pa intaneti ndipo ikafika pamalo ake, imachotsedwa kumbuyo kwa dziko loyambirira isanatchulidwe. Nthawi zambiri, sizingatheke kuti decompress data ikhale yobwereranso, chifukwa deta yowonjezereka yayamba kale kugwiritsidwa ntchito.
Mitundu ya kuponderezana
Deta ikadapangidwira, imakhala yowala ndipo makamaka ntchito imakhala yabwino. Komabe, zimakhala kuti njira zabwino zowonongeka zimachepetsa ubwino wa deta. Pali mitundu iŵiri ya kuponderezana: yopanda kanthu komanso yotayika. Ndi kupanikizika kopanda kanthu, simukusowa kanthu, koma simungathe kupanikizika kwambiri. Ndi kutaya mtima, mumapindula kwambiri, koma mumataya khalidwe. Nthawi zambiri simungatengere deta yovomerezeka kumalo ake oyambirira ndi kuperewera, popeza khalidweli linaperekedwa chifukwa cha kukula kwake. Koma izi ndi nthawi yambiri yosafunika.
Chitsanzo chabwino cha kuperewera kwachisokonezo ndi MP3 kuti muzimvetsera. Mukamangomvera nyimbo, simungathe kubwezeretsa, MP3 mumakonda kumva bwino, poyerekeza ndi mafayilo akuluakulu a audio.
Kusindikiza - decryption
Kujambula zithunzi ndi chimodzi mwa zipangizo zabwino zopezera chitetezo. Ndi njira yosinthira deta muzochitika zotere kuti palibe amene angamvetse. Mwanjira iyi, ngakhale ngati deta yolumikizidwa ikutsatiridwa ndi anthu osaloledwa, deta ilibebe chinsinsi. Deta ikadatha kufika, imachotsedwa kubwerera ku mawonekedwe ake oyambirira. Kawirikawiri, pamene deta ikuphwanyidwa, yayimilidwa kale, chifukwa imasinthidwa ndi chikhalidwe chake choyambirira.
Pitani ku mndandanda uwu pa mndandanda wa codecs zomwe zimagwiritsidwa ntchito pa VoIP .