I-Chrominance: Yintoni kwiMveliso yeVidiyo?

ngo kim Ukuhlaziywa: Juni 27, 2022

I-chrominance yenye yezona zinto zibalulekileyo ze yokuzonwabisa imveliso. Inempembelelo enkulu kwindlela ebonakalayo ebonakalayo kwividiyo kwaye ingasetyenziselwa ukuphucula umgangatho wemifanekiso yevidiyo.

I-Chrominance ibhekisa kwi umbala, ukugcwala, kunye nokuqina ye imibala kwividiyo.

Kweli nqaku, siza kuxubusha ngakumbi ngechrominance kwaye sijonge indima yayo kwimveliso yevidiyo.

Inkcazo yeChrominance

I-chrominance (ekwaziwa njengombala) lilungu lemveliso yevidiyo ehambisa i-hue kunye nokugcwala komfanekiso. Lelinye lamacandelo amabini ophawu lwevidiyo, elinye libe lilo ukukhanya (ukukhanya). I-Chrominance imelwe yimibala emibini elungelelanisiweyo- Cb kunye noCr – ezithi xa zidibene zimele ipalethi yombala eyahlukileyo xa kuthelekiswa nolungelelwaniso lokukhanya kweY.

I-Chrominance iqulethe ulwazi malunga ne umgangatho, umthunzi, i-tint kunye nobunzulu bemibala kumqondiso wevidiyo. Umzekelo, i-chrominance ingasetyenziselwa ukwahlula iithowuni zesikhumba kweminye imibala emfanekisweni ngokuchonga iipikseli ezinamaxabiso athile ombala. Ngokufanayo, i-chrominance ingasetyenziselwa ukuphucula iinkcukacha ezifana ukuthungwa okanye ukwahluka okuncinci ekukhanyeni, e yedijithali iifomati zevidiyo, ichrominance igcinwa ngokwahlukileyo kumaxabiso okukhanya, ivumela ucinezelo olusebenzayo ngakumbi lwedatha ngaphandle kokuthomalalisa kumgangatho wemifanekiso.

Imbali yeChrominance

I-chrominance, okanye Chroma, yenye yezinto ezimbini zombala ezisetyenziswa kwimveliso yevidiyo (kunye nokukhanya). Ibalwa ngokulinganisa ubukhulu bokukhanya kwimibala ethile - rhoqo obomvu, oluhlaza kunye noluhlaza okwesibhakabhaka. Okukhona i-hue ethile iqaqamba, kokukhona inechroma eninzi.

Igama elithile 'chrominance' yaqalwa nguWalter R. Gurney ngo-1937 kwaye ihlala ingatshintshanga ukusukela ngoko. Ukusukela ngoko, ibisetyenziswa kakhulu kwimveliso kamabonwakude njengoko imibala yayo emithathu ephambili (ebomvu, eluhlaza nebhlowu) ihambelana ngokusondeleyo naleyo yetyhubhu yemibala kamabonwakude ukusukela oko yaqalayo. Ngoxa oomabonwakude banamhlanje bengasezizo iityhubhu ze<em>cathode-ray ezisekelwe kulwazi lwechroma neluma, iikhamera ezininzi zanamhlanje zisaqhubeka zisebenzisa ezi nxalenye ukuze zibhale imifanekiso enemibala.

I-Chrominance ivumela ukurekhodwa ngokuchanekileyo kombala kunoko bekufumaneka kwifilimu ye-monochrome (emnyama namhlophe) ngaphambi kokuphuhliswa kweenkqubo zevidiyo ezihlanganisiweyo ngo-1931. I-Chrominance idla ngokulinganiswa kusetyenziswa i-oscilloscope okanye i-waveform monitor echonga utshintsho olufihlakeleyo kumanqanaba ombala kuwo onke amalungu. yomfanekiso wevidiyo - kwanabo bangabonakali ngeso lenyama-ukuqinisekisa ukuba imibala ihlala ingaguquguquki phakathi kweekhamera kunye nezixhobo ngexesha leenkqubo zokuvelisa emva kokuvelisa ezifana nokuhlelwa kunye nokufakwa kweekhowudi kwiifomathi zokusasazwa kwedijithali njengeenkonzo zokusasaza i-intanethi okanye imidiya yediski efana Iidiski zeBlu-Ray okanye iiDVD.

Amacandelo eChrominance

I-chrominance lulwazi lombala olusemfanekisweni okanye kwividiyo enceda ukudala imvakalelo yendalo. I-chrominance ibandakanya amacandelo amabini: hue kwaye indawo yokuhlala.

• Hue ngowona mbala womfanekiso.
• Indlela epholileyo sisixa sombala osulungekileyo okhoyo emfanekisweni.

Zombini ziyimiba ebalulekileyo yokuveliswa kwevidiyo kwaye ziya kuxoxwa ngeenkcukacha ezithe vetshe ngezantsi.

Hue

Hue lelinye lamacandelo enza ichrominance. Ligama elisetyenziswa kwimveliso yevidiyo ukumela indawo yombala ecaleni kwespectrum ukusuka obomvu ukuya eluhlaza ukuya eluhlaza. I-hue inquma ukuba nguwuphi umbala okhoyo kunye nendlela egcwele ngayo ibonakala kumfanekiso. I-Hue inokumelwa njengenani phakathi 0 kunye ne-360 degrees, kunye no-0 obomvu, i-120 eluhlaza, kunye ne-240 eluhlaza. Idigri nganye yahlulwe ngokwandiswa kwe-10, ngexabiso le-hexadecimal njenge 3FF36F emele imibala ethile.

Ukongeza kwinkcazo ye-hue ye-monochrome yendabuko yeendlela ezintathu, ezinye iinkqubo zokucinga zisebenzisa iinkcazo ze-hue ezine okanye ezintlanu kwiinkcazo ezichanekileyo zokwahluka kwe-hue.

Indlela epholileyo

Indlela epholileyo, ngamanye amaxesha kuthiwa ikroma or chrominance, yinxalenye yombala kwimveliso yevidiyo. Ukuzaliswa kulinganisa ubungakanani bengwevu kumbala. Umzekelo, i-lime eluhlaza ine-saturation eninzi kune-grayish-green; uhlaza olufanayo lunokuba nezahlulo ezahlukeneyo ngokuxhomekeke kwindlela eqaqamba ngayo. Xa i-saturation inyuswa kumfanekiso, i-hue kunye nokukhanya kwayo kuya kuba nzima ngakumbi; xa iyancipha, i-hue kunye nobuhle buyancipha.

Umlinganiselo ochaza inqanaba lokuzaliswa kumfanekiso waziwa ngokuba amanqanaba chrominance; oku kubhekisa kwiithowuni ezisuka kumnyama (akukho chrominance) ukuya kumbala ogcwele ngokupheleleyo ngokobukhulu bawo. Ngokulungelelanisa la manqanaba uyakwazi ukwenza izilungiso zemibala okanye uphucule imibala ngaphakathi komfanekiso wakho ngokuqinisa iithowuni ezithile okanye udale umahluko obanzi phakathi kwemibala emnyama kunye nokukhanya. Oku kungasetyenziswa jikelele kuyo yonke imibala emfanekisweni wakho, okanye yaphulwe kwaye ihlengahlengiswe ngamajelo athile ombala aquka nayiphi na indawo echaphazelekayo yesakhelo (enje nge ezibomvu okanye blues).

Luminance

Ukukhanya yinxalenye ebalulekileyo yechrominance kwaye inxulunyaniswa nembono yokukhanya. Kuso nasiphi na isithuba sombala esinikiweyo, ukukhanya ngumlinganiselo ozimeleyo wokuba njani eqaqambileyo okanye buthuntu umbala othile ubonakala ngathi. Inqanaba lokukhanya linokuchaphazela indlela umxholo ovela ngayo ngokwemiqathango yokuchasana, ukugcwala, kunye namanqanaba ombala.

Kwimveliso yevidiyo, ukukhanya kudlala indima ebalulekileyo ekumiseleni i ukuqaqamba komfanekiso. Umzekelo, ukuba umfanekiso unamanqanaba aphezulu okukhanya ngokugqithisileyo, uya kubonakala uhlanjiwe kwaye ubuthuntu, kanti umfanekiso onesikhanyiso esiphantsi kakhulu uya kubonakala umnyama kwaye unodaka. Ke ngoko, abavelisi bevidiyo kufuneka bahlengahlengise amanqanaba okukhanya ukuze bafezekise iziphumo ezifunwayo kwindawo nganye.

Uninzi lweevidiyo ezisebenzayo zibandakanya a "luma ijika" evumela iingcali zevidiyo ukuba zenze uhlengahlengiso olungenabugocigoci ukuze kulungiswe kakuhle imifanekiso yezixhobo eziphumayo ezifana nezikrini zikamabonakude okanye iiprojektha zedijithali ezineempawu ezahlukeneyo zokutolika ulwazi lombala. I-Luma curves yenziwe ngamanqaku alishumi elinesithandathu amele amanyathelo ali-16 ahlulwe ngokulinganayo kwisikali sokukhanya-mnyama (ukusuka ku-0-3) ngaphakathi koluhlu oluthile olumele u-zero omnyama ngasekhohlo kunye nomhlophe kwicala lasekunene ebonisa ithoni epheleleyo echanekileyo kuyo yonke imifanekiso ngaphakathi kolandelelwano lonke okanye inkqubo. .

Iintlobo zeChrominance

I-chrominance ligama elisetyenziswa kwimveliso yevidiyo ukuchaza umahluko phakathi kokukhanya kunye nechromaticity. Isetyenziselwa ukulinganisa ukuzaliseka kwemibala kwividiyo, kwaye ingasetyenziselwa ukubona utshintsho ekukhanyeni kunye nombala.

Kukho iintlobo ezimbini zeChrominance: ukukhanya kwaye chrominance. Uhlobo ngalunye luneempawu zalo ezizodwa kunye neenzuzo zokuveliswa kwevidiyo. Siza kuhlola zombini iintlobo kweli nqaku.

RGB

RGB (obomvu, oluhlaza, oluhlaza okwesibhakabhaka) yimodeli yombala esetyenziswa kakhulu kwimveliso yevidiyo yedijithali kunye noyilo xa udibanisa imibala ephambili yomfanekiso okanye ividiyo. I-RGB yenza ukukhanya okumhlophe kwimithombo yokukhanya emithathu enemibala edityanisiweyo ukwenza umqadi omnye. Le nkqubo yemibala idala imibala efana neyobomi ngokubonisa ubuninzi bemibala kunye ukuze ilinganise ngokusondeleyo kangangoko kunokwenzeka oko kunokubonwa ngeliso lomntu.

Umthombo umiselwe usebenzisa i-encoder yamajelo amathathu yokulinganisa phakathi kokugcwala kunye nokuqaqamba, ivumela umbala ngamnye ophambili (obomvu, oluhlaza okwesibhakabhaka kunye nohlaza) ukulawulwa ngokuzimeleyo kwabanye. Inzuzo ephambili yalo mzekelo kukusebenza kwayo okugqwesileyo ngokwemiqathango ukukhanya kunye nokuchaneka xa kuziwa ekuveliseni imibala edlamkileyo.

I-YUV

I-YUV, ekwaziwa njenge YCbCr, sisikhanyiso (Y) kunye nezinto ezimbini zechrominance (U kwaye V). Amalungu e-chrominance esithuba sombala wedijithali abonisa ukuba umbala unjani na umqondiso. I-YUV, esetyenziswa ngokuqhelekileyo kwiifoto zedijithali kunye nevidiyo, yindibaniselwano yokukhanya kunye namaxabiso amabini e-chrominance amele iimpawu ezahlukeneyo zobomvu kunye nohlaza okwesibhakabhaka. Le nkqubo ivumela ukuncitshiswa kweemfuno ze-bandwidth xa kuthelekiswa nokusetyenzwa komqondiso weRGB kwimveliso yevidiyo.

Kwimodeli ye-YUV, isignali ebomvu imelwe njenge "OKANYE" ngelixa uphawu oluluhlaza lumelwe njenge "V", kunye nokukhanya (Y). Iimpawu ze-U kunye ne-V zithatyathwa kwi-luminance iyonke ukubonisa iinkcukacha ezimibalabala kumfanekiso. Ukudibanisa la maxabiso mathathu kusinika isiqabu kwimfuno ye-bandwidth ngelixa sigcina umgangatho ulungile ngexesha lokufakwa kwekhowudi yevidiyo / inkqubo yokusasaza.

Ifomathi yombala we-YUV ixhaswa ngokwemveli ziikhamera zevidiyo zabathengi kunye neefayile zeJPG zemifanekiso ezithathwe ziifowuni eziphathwayo ezihlala zithatha imifanekiso zisebenzisa ifomathi yeYUV ngaphambi kokuyicinezela kwiiJPEGs. Ukuqhubela phambili ezantsi emgceni, xa usasaza okanye ufaka ikhowudi kule mifanekiso inceda kakhulu kuba idatha encinci idinga ukuhanjiswa ngenxa yokuba ngcono kwayo. umgangatho-kuya-umrhumo weempawu. Ngenxa yezi mpawu kukhethwa ngaphezu kwe-RGB ngeenjongo zokusasaza apho kunokulindeleka ilahleko ekumgangatho ophantsi ngenxa yayo imfuneko yobubanzi obuphantsi xa yamkelwa kwiinkqubo ze-encoding/streaming.

YIQ

YIQ luhlobo lwechrominance edla ngokusetyenziswa kunye neefomati zevidiyo ze-analog endala ye-NTSC. Icandelo le-Y libamba ukukhanya komfanekiso, ngelixa i-I kunye ne-Q ibamba umbala okanye i-chrominance. Isebenza ngokwahlula umbala onikiweyo kumacandelo awo kunye ne-xy axis, eyaziwa ngokuba yi-Hue (H) kunye noSaturation (S). Amaxabiso e-YIQ ke asetyenziselwa ukwenza i-matrix ye-RGB evumela ukuveliswa kombala ngokuchanekileyo kwiinkqubo ezahlukeneyo.

YIQ ngokusisiseko ithatha isiginali yeRGB kwaye iyahlulahlula ibe ngamacandelo amathathu:

• Y (Ukukhanya)
• I (kwinqanaba umbala)
• Q (umbala wequadrature)

Umahluko phakathi kwesigaba kunye ne quadrature components unobuqili, kodwa ngokusisiseko ndibamba iperi enye yemibala ephambili, ngelixa u-Q ebamba isibini sesibini. Ngokudibeneyo ezi tshaneli zintathu ziyakwazi ukwenza umahluko obonakala ungenasiphelo kwi-hue, saturation, kunye nokukhanya okuvumela ababukeli ukuba bazenzele amava abo okubukela.

YCbCr

I-YCbCr (ehlala ibizwa ngokuba yi-Y'CbCr) luhlobo lwechrominance eyenziwe ngamajelo amathathu. Ezi tshaneli zi Iluma (Y), Umahluko oluhlaza wechroma (Cb) kwaye Umahluko obomvu wechroma (Cr). I-YCbCr isekwe kuguqulelo lwe-analog ebizwa ngokuba yi-YPbPr, iyenza ifane ngeendlela ezithile kwisithuba sombala we-RGB. Nangona i-YCbCr isetyenziswa rhoqo kwimveliso yevidiyo, imifanekiso yedijithali inokufakwa ngekhowudi ngendlela efanayo.

Ingcamango emva kweYCbCr kukuba inciphisa inani ledatha efunekayo ukumela umfanekiso wombala. Ngokwahlula ulwazi olungakhanyisiyo kwezinye iziteshi ezimbini, inani elipheleleyo ledatha yomfanekiso wonke lingancitshiswa kakhulu. Oku kuvumela ividiyo ekumgangatho ophezulu okanye imifanekiso yedijithali enobungakanani beefayile ezincinci, okwenza kube lula ukugcina nokuhambisa.

Ukuze kuphunyezwe oku kuncitshiswa kobungakanani bedatha, amanqanaba ahlukeneyo okuchaneka asetyenziswa phakathi kweshaneli nganye. Iluma inokuba nesisombululo se-8 bits kunye ne-chrominance 4 okanye i-5 bits. Kuxhomekeka kuhlobo lwesixhobo osisebenzisayo kukho amanqanaba amaninzi akhoyo, kubandakanywa:

• 4:4:4 kwaye 4:2:2 (amasuntswana ama-4 kumjelo ngamnye),
• 4:2:0 (iibhithi ezi-4 zeluma, ezi-2 zebhlowu nezi-2 zobomvu).

Usetyenziso lweChrominance

I-chrominance, xa isetyenziswa kwimveliso yevidiyo, ibhekisa kusetyenziso lwe faka umbala kwividiyo. I-Chrominance sisixhobo esibalulekileyo sokudala izinto ezibonakalayo ezicacileyo nezicacileyo, ezivumela abalawuli ukuba baphucule imo kunye neemvakalelo zendawo.

Eli nqaku liza kuphonononga iindlela ezahlukeneyo enokuthi i-chrominance isetyenziswe ngayo kwimveliso yevidiyo, kubandakanya nokusetyenziswa kwe:

• Ukuhlelwa kombala
• Ukufaka umbala
• Imibala yemibala

Ukuhlela umbala

Enye yezona zicelo zibalulekileyo zechrominance kwimveliso yevidiyo umbala. Ukuhlelwa kombala yindlela yokuphucula umfanekiso wevidiyo. Njengoko igama lisitsho, isebenzisa iindlela ezahlukeneyo zokulungisa imibala, saturations kunye nezinye iimpawu zokwenza isitofu sigqame okanye sidibane kwindawo eyingqongileyo. Amanqanaba eChrominance zibaluleke kakhulu kule nkqubo, njengoko zingasetyenziselwa ukudala isimo sengqondo okanye ithoni ethile.

Umzekelo, ukuba umboniso usetwe elunxwemeni lolwandle ekuzeni kokusa kwaye kufuneka ube nemvakalelo ye-ethereal, amanqanaba e-chrominance anokulungelelaniswa ngokufanelekileyo ukuze kuphuculwe ukukhanya kwelanga okufudumeleyo kunye nokongeza i-shades eluhlaza okwesibhakabhaka ukuziva umoya. Ngokufanayo, ukuba umboniso ufuna imvakalelo engaphezulu okanye idrama, amanqanaba okugcwala anokunyuswa ngelixa ugcina ingqibelelo yomgangatho womfanekiso wokuqala ngokulungelelanisa ngokusebenzisa ulawulo lwechrominance.

Ukuhlelwa kombala kunceda ekuqinisekiseni ukuba zonke iifowuthi kwiprojekthi ethile zibonakala zingaguquguquki ngokweethowuni kunye nokuziva ukuze ukuhlela kunye nokuveliswa kwemveliso kuhamba kakuhle.

Ukunyaniseka kwevidiyo

Ukunyanzeliswa kwevidiyo yinkqubo yokususa ulwazi kwisignali yevidiyo ukwenzela ukunciphisa ubungakanani befayile okanye i-bandwidth yokuhambisa. Oku kubandakanya ukunciphisa iinkcukacha kunye/okanye isisombululo sayo nayiphi na ividiyo enikiweyo. I-chrominance ibaluleke kakhulu kule nkqubo njengoko imisela iimpawu zemibala ngaphakathi komqondiso wevidiyo.

Ngokunciphisa i-chrominance, ukunyanzeliswa kwevidiyo kunokwenza iinzuzo ezibalulekileyo malunga nokugcinwa kwedatha kunye nokuhambisa ukuhanjiswa, kunye nefuthe elincinci kumgangatho. I-Chrominance inokusetyenziswa kwiindidi ezininzi ezahlukeneyo zemidiya, ezifana nosasazo lukamabonakude, iividiyo zokusasaza kunye neediski ze-Blu-ray.

Njengoko i-chrominance ithwala ulwazi olubalulekileyo olubonakalayo esilubiza ngombala, ukuyifaka kwiikhowudi kancinci kodwa ngokusebenzayo kusivumela ukuba sicinezele iividiyo ngaphandle kokuncama ukuchaneka kombala okanye ukugcwala - izinto ezimbini ezibalulekileyo ekudaleni. imbonakalo eyinyani. I-Chrominance ichaphazela ukuba ingakanani idatha efunekayo ukugcina kunye/okanye ukuhambisa umxholo we-audio-visual; ngokuyisebenzisa ngokupheleleyo, sibonisa ukuhlala sincinci ngelixa sigcina a umgangatho ophezulu womgangatho kwimifanekiso yethu.

Ukulungiswa kombala

Uphawu lwechrominance sesinye esichaza ubungakanani bombala kumfanekiso, kunokukhanya. Kwimveliso yevidiyo kunye nokulungiswa kwangemva, ukumisela ibhalansi eyimpumelelo yechrominance kubandakanya ukusebenzisa isoftware ukulungisa ubushushu bombala womfanekiso okanye umfanekiso. Le yinkqubo eyaziwa ngokuba ukulungiswa kombala.

Ukulungiswa kombala kwividiyo emva kokuveliswa kuhlala kubhekisa kulo naluphi na utshintsho lwemifanekiso ekhoyo efana ne ukwanda okanye ukuncipha kokugcwala, ukulungisa ibhalansi emhlophe, kunye nokutshintsha imiba ethile yokuchasana. Olu lungiso lunokuyitshintsha inkangeleko yemifanekiso ngokubonakalayo ngokutshintsha indlela ukukhanya kunye nobumnyama okwenziwa ngayo, indlela imibala exutywa ngayo enye kwenye, ubunzulu bemibala eyahlukeneyo kwimbonakalo, kunye nokunye.

Ngamafutshane, uhlengahlengiso kwichrominance lusebenza njengesixhobo sokunika nawuphi na umboniso ithoni kunye nemo esele imiselwe kwangaphambili. Ukulungiswa kombala ngokuqhelekileyo kwenzeka xa kukho imibala engachanekanga okanye engangqinelaniyo kumfanekiso wonke nto leyo enokukhokelela ekubhidekeni xa uzama ukutolika intsingiselo okanye injongo yawo. Umzekelo, ukuba ukukhanya kwiseti akuhambisani ncam ukusuka kwindawo ukuya kwindawo, oku kunokukhokelela kumahluko ngemibala phakathi kweefoto ezimbini ezithathiweyo imizuzu enye kwenye. Ngohlengahlengiso lwe-chrominance oku kubhideka kunokuncitshiswa ngokubuyisela yonke into kwimvisiswano nayo ngokwayo - ngokukodwa ngokuphathelele imibala yayo - ke ibonakala ikhanyiswe ngokufanelekileyo kwaye ihambelana ngokwetoni noko bekujongwe njengenxalenye yethagethi yobuhle beqhekeza.

isiphelo

Ukushwankathela, chrominance ngumba wombala onokuthi utshintshwe kwaye usetyenziswe xa kusenziwa ividiyo. Chrominance, okanye ikroma ngokufutshane, kumiselwa ngokulinganisa i umbala kunye nokugcwala yombala ukuyinika inkangeleko yayo eyodwa. Ukulawula i-chrominance sisixhobo esinamandla sabenzi befilimu, njengoko banokusisebenzisa ukwenza imiboniso ye-surreal kunye nenhle ngeendlela zokukhanyisa ezinobuchule.

Ngokuqonda iziseko zechrominance, abenzi befilimu banokuba nolawulo olungakumbi lobuchule kumoya weeprojekthi zabo.

Molo, ndinguKim, umama kunye nomthandi we-stop-motion onemvelaphi kwindalo yemidiya kunye nophuhliso lwewebhu. Ndinothando olukhulu lokuzoba kunye noopopayi, kwaye ngoku ndintywila kuqala kwihlabathi le-stop-motion. Ngebhlog yam, ndabelana nawe ngokufunda kwam.