Izizathu Okwenza i-Bluetooth inganciphisa ikhwalithi yomsindo
I-Bluetooth isheshe ibe yindlela ejwayelekile kunazo zonke yokujabulela umsindo we-wireless ngokusebenzisa izikhulumi nama-headphones. Kodwa-ke, ukukhathazeka okukodwa abanye abanayo ngokuqondene ne-Bluetooth nokunciphisa jikelele ikhwalithi yezwi. Kukhona labo abazizwa ukuthi - kusukela ekuboneni kweqiniso lokulalela - uhlale ungcono ekukhetheni enye ye- Wi-Fi-based technology wireless technologies , njenge-AirPlay, i-DLNA, i-Play-Fi, ne-Sonos.
Ngenkathi leyo nkolelo ivame ukulungile, kuningi ukusebenzisa i-Bluetooth kunalokho ongase ukwazi.
I-Bluetooth ekuqaleni ayidalwanga ekuzijabuliseni komsindo, kodwa ukuxhuma ama-headsets efoni kanye nama-speakersphone. Kwakhiwe futhi nge-bandwidth encane kakhulu, okuyiphoqa ukuba isebenzise ukucindezelwa kwedatha kwisignali yomsindo. Ngenkathi lokhu kungase kube kuhle kakhulu izingxoxo zefoni, akuyona into enhle yokukhiqiza umculo. Akukhona lokho kuphela, kodwa i-Bluetooth ingasebenzisa lokhu kucindezela ngaphezulu kokucindezela kwedatha okungenzeka kuvele kukhona, okuvela kumafayela womsindo we-digital noma imithombo esakazwa nge-intanethi. Kodwa into eyodwa ebalulekile okufanele uyikhumbule ukuthi uhlelo lwe-Bluetooth aludingeki lisebenzise le nkinga eyengeziwe. Nasi isizathu:
Wonke amadivayisi we-Bluetooth kufanele asekele i-SBC (imelela i-Low Complexity Subband Coding). Noma kunjalo, amadivaysi e-Bluetooth angase asekele ama-codec ozikhethela, angatholakala kwi-Bluetooth Advanced Advanced Distribution Profile (A2DP).
Ama-codec okukhethwa kukho okubalwe yiwo: MPEG 1 & 2 Audio (MP2 ne-MP3), MPEG 3 & 4 (AAC), ATRAC, ne-AptX. Ukucacisa okubili kwalokhu: Indlela ejwayelekile ye-MP3 empeleni i-MPEG-1 Layer 3, ngakho-ke i-MP3 ihlanganiswa ngaphansi kwe-spec njenge-codec yokuzikhethela. I-ATRAC iyi-codec eyasetshenziswa ngokuyinhloko kumikhiqizo yakwa-Sony, ikakhulukazi ekufomeni kwe-MiniDisc yokuqopha digital.
Ake sibuke imigqa embalwa ukusuka ku-A2DP esetshenzisiwe, esitholakala njengedokhumenti ye-PDF ku-Bluetooth.org.
4.2.2 I-Codec engakhethwa
Idivayisi ingase futhi isekele ama-codec ongakhethayo ukuze ukwandise ukusebenza kwayo. Uma kokubili i-SRC ne-SNK isekela i-codec efanayo yokuzikhethela, le codec ingasetshenziswa esikhundleni se-Codec evunyelwe.
Kulo dokhumenti, i-SRC ibhekisela kudivayisi yomthombo, futhi i-SNK ibhekisela kudivayisi yokucwenga (nobe ukuphela). Ngakho umthombo wawuzoba yi-smartphone, ithebulethi, noma ikhompyutha yakho, futhi inkinga ingaba isikhulumi sakho se-Bluetooth, i-headphone, noma i-receiver.
Lokhu kusho ukuthi i-Bluetooth akudingeki ukuthi yengeze ukucindezelwa kwedatha eyengeziwe kwimpahla esevele icindezelekile. Uma kokubili umthombo nokucima amadivayisi kusekela i-codec esetshenziselwa ukumisa isignali yomsindo wokuqala, umsindo ungadluliselwa futhi wamukelwe ngaphandle kokuguqulwa . Ngakho-ke, uma ulalele amafayela e-MP3 noma ama-AAC oyigcine kwi-smartphone yakho, ithebulethi, noma ikhompyutha, i-Bluetooth akudingeki ihlaziye ikhwalithi yomsindo uma amadivayisi womabili asekela lelo fomethi.
Le mithetho iphinda isebenze kumsakazo we-intanethi nokusabalalisa umculo amasevisi afakwe kwi-MP3 noma i-AAC, ehlanganisa okuningi kokutholakala namuhla. Noma kunjalo, ezinye izinsizakalo zomculo bezihlolisise amanye amafomethi, njengokuthi i-Spotify isebenzisa kanjani i- Ogg Vorbis codec .
Njengoba wonke umkhawulokudonsa we-intanethi ukwanda ngokuhamba kwesikhathi, singase sibone izinketho eziningi futhi ezingcono esikhathini esizayo esiseduze.
Kodwa ngokusho kwe-Bluetooth SIG, inhlangano evumela i-Bluetooth, ukucindezelwa kuyisimiso manje. Lokhu kungenxa yokuthi ifoni kumele ikwazi ukudlulisela umculo hhayi kuphela kodwa ibuye ibe neminye imininingwane kanye neyezinye izaziso ezihlobene nocingo. Noma kunjalo, asikho isizathu sokuthi umkhiqizi akakwazi ukushintsha kusuka ku-SBC kuya ku-MP3 noma ukucindezela kwe-AAC uma idivaysi yokuthola i-Bluetooth isekela. Ngakho izaziso zingaba nokusetshenziselwa ukucindezelwa, kodwa amafayela we-MP3 noma ama-AAC azodlula angadluli.
Kuthiwani Nge-AptX?
Ikhwalithi yomsindo we-stereo nge-Bluetooth uye wakhula ngokuhamba kwesikhathi. Noma ubani oqaphela okwenzekayo ku-Bluetooth uzwile nge- codec ye- aptX , edayiswa njengendlela yokuthuthukiswa ku-codec ye-SBC egunyaziwe. Isimangalo sokuthi udumo lwe-aptX yikhono layo lokuletha ikhwalithi ye-"CD-like" ye-Bluetooth ngaphandle kwentambo ye-Bluetooth. Mane ukhumbule ukuthi kokubili amadivayisi we-Bluetooth nomthombo wokukhipha kumele asekele i-codec ye-aptX ukuze azuze. Kodwa uma udlala i-MP3 noma i-AAC impahla, umkhiqizi angase abe ngcono ukusebenzisa ifomethi yangempela yefayela elilalelwayo ngaphandle kokufaka kabusha ikhodi eyengeziwe nge-aptX noma i-SBC.
Imikhiqizo eminingi ye-Bluetooth yomsindo ayikwakhiwa yinkampani izisebenzi zabo ezigqoka umkhiqizo wazo, kodwa nge-ODM (umkhiqizi wangempela womklamo) ongakaze uzizwe. Futhi isamukeli se-Bluetooth esisetshenziswe kumkhiqizo womsindo mhlawumbe asizange senziwe yi-ODM, kodwa ngomunye umakhi. Labo abaye embonini bafunde ukuthi kunzima kakhulu umkhiqizo wedijithali, futhi uma kukhona onjiniyela abaningi abasebenza kuwo, cishe kungenzeka ukuthi akekho owaziyo konke okwenzekayo ngaphakathi kwedivayisi. Ifomethi eyodwa ingadluliselwa kalula kwenye, futhi awusoze wazi ngoba cishe ayikho idivaysi yokuthola i-Bluetooth izokutshela ukuthi ifomethi engenayo iyini.
I-CSR, inkampani ene-codec ye-aptX, ithi i-signal ye-audio enikwe amandla ye-AptX inikezwa ngokuqondile ngaphezu kwesixhumanisi se-Bluetooth. Nakuba i-AptX uhlobo lokucindezela, kufanele ukuthi isebenze ngendlela engathinteli ukuthembeka kwe-audio (ngokuhambisana nezinye izindlela zokucindezela).
I-codec ye-aptX isebenzisa inqubo ekhethekile yokunciphisa isilinganiso esincane esichaza yonke imvamisa yomsindo ngenkathi ivumela idatha ukuba ifane phakathi kwe-"pipe" ye-Bluetooth engenantambo. Izinga ledatha lilingana nelomculo womculo (16-bit / 44 kHz), ngakho-ke kungani inkampani ilinganisa i-aptX ne "CD-like" umsindo.
Kodwa kubalulekile ukuqaphela ukuthi zonke izinyathelo kulayini lomsindo zithinta ukukhipha umsindo. I-codec ye-aptX ayikwazi ukukhokhela ama-headphones / izikhulumi ezingezansi ephansi, amafayili alalelwayo / imithombo yomsindo ophansi, noma amakhono ahlukahlukene aguquguquli be- digital-to-analog (ama-DAC) atholakele kumadivayisi. Isimo sokulalela kufanele sicatshangelwe futhi. Noma yikuphi ukuthembeka okutholakala ngeBluetooth nge-AptX kungavinjelwa umsindo, njengokusebenzisa imishini / i-HVAC, imoto yezimoto, noma izingxoxo eziseduze. Ngalokho engqondweni, kungase kudingeke ukhethe izikhulumi ze-Bluetooth ngokusekelwe kuzici nama- headphone ngokusekelwe enduduzo kunokuhambisana kwe-codec.
Kubalulekile ukuqaphela ukuthi ngenkathi i-Bluetooth (njengoba isetshenziswa ngokujwayelekile) ihlaziye ikhwalithi yomsindo (ngezinga elihlukile), akudingeki. Ngokuyinhloko kuze kubakhiqizi bedivaysi ukusebenzisa i-Bluetooth ngendlela ethinta ikhwalithi yomsindo okungenani - noma mhlawumbe, neze. Khona-ke kufanele ucabange ukuthi ukungezwani okucashile phakathi kwama-codec alalelwayo kungaba nzima ukuzwa, ngisho nasesimisweni esihle kakhulu. Ezimweni eziningi, i-Bluetooth ngeke ibe nomthelela omkhulu kwizinga elizwakalayo ledivayisi yomsindo. Kodwa uma uke ube nokubhuka futhi ufuna ukuqeda konke ukungabaza, ungahlala ujabulela umculo ngokuxhuma imithombo usebenzisa ikhebula lomsindo .