Tus txheej txheem ntawm cov ntaub ntawv compression txo nws volume

Niaj hnub no, muaj coob tus neeg xav txog yuav ua li cas rau cov ntaub ntawv compression txheej txheem nyob rau hauv thiaj li yuav cawm tau hard disk qhov chaw, nws yog ib qho ntawm feem kev siv ntawm cov nqi qhov chaw nyob rau hauv tej cia ntaus ntawv. Heev feem ntau, advanced cov neeg uas yog ntsib nrog tus tsis muaj qhov chaw dawb rau koj kev tsav, nws yog tsim nyog los tshem tawm tej ntaub ntawv nyob rau hauv ib qho kev sim dawb rau hauv qhov chaw, thaum ntau tshaj cov neeg siv feem ntau siv cov ntaub ntawv compression nyob rau hauv thiaj li yuav txo nws volume.

Txawm li cas los, muaj ntau yam tsis txawm paub lub npe ntawm tus txheej txheem ntawm compression ntawm cov ntaub ntawv, tsis txhob hais dab tsi algorithms siv, thiab hais tias muab daim ntawv thov ntawm txhua tus ntawm lawv.

Seb puas yuav hlob cov ntaub ntawv?

Cov ntaub ntawv compression yog ib qho tseem ceeb txaus rau hnub tim, thiab nws yog tsim nyog rau cov neeg siv. Ntawm cov hoob kawm, nta yuav luag txhua tus muaj peev xwm yuav tshaj cov ntaub ntawv cia, muab tau ntawm kev siv ib tug txaus loj npaum li cas ntawm qhov chaw dawb, thiab nruab nrog high-ceev cov ntaub ntawv broadcasting raws.

Txawm li cas los, nws yuav tsum tau kom to taub thiab hais tias lub ntim ntawm cov ntaub ntawv uas yuav tsum tau kis kuj yuav tsub kom lub sij hawm. Thiab yog hais tias cia li kaum xyoo dhau los, tus txheej txheem rau cov pa zaj duab xis mas suav hais tias yuav tsum tau lub ntim ntawm 700MB, lub hnub films, ua nyob rau hauv HD zoo, tej zaum yuav muaj ib tug ntim sib npaug zos rau ob peb kaum tawm ntawm gigabytes, tsis hais ntau npaum li cas qhov chaw yog nyob los ntawm cov high-zoo duab nyob rau hauv Blu-duab tshav hom ntawv.

Thaum cov ntaub ntawv compression yog tsim nyog?

Ntawm cov hoob kawm, ib tug yuav tsum tsis xav hais tias cov ntaub ntawv compression txheej txheem yuav coj koj ntau yam kev pab, tab sis muaj ib tug tej yam muaj pes tsawg tus ntawm lub sijhawm nyob rau hauv uas ib txhia cov ntaub ntawv compression hom kev kawm yog cov tsis tshua pab tau, thiab txawm tsim nyog:

• Hloov ntawm tej ntaub ntawv los ntawm e-mail. Qhov no yog tshwj xeeb tshaj yog muaj tseeb rau cov neeg lub sijhawm thaum koj xav tau kev ntaub ntawv rau ib tug loj scale, siv ib tug ntau yam ntawm mobile pab kiag li lawm.
• Feem ntau cov ntaub ntawv compression txheej txheem nyob rau hauv thiaj li yuav txo cov nyob qhov chaw nws yog siv nyob rau hauv daim ntawv ntawm tej yam ntaub ntawv nyob rau hauv ntau qhov chaw uas yuav tsum tau tseg bandwidth;
• Txuag qhov chaw rau koj nyuaj tsav nyob rau hauv cov kev tshwm sim hais tias nws tseem tsis tau mus hloov los yog ntxiv tshiab cia chaw. Nyob rau hauv kev, feem ntau teeb meem no yog hais tias thaum muaj tej yam kev txwv nyob rau hauv lub muaj pob nyiaj siv, tab sis nws tsis muaj txaus free disk qhov chaw.

Ntawm cov hoob kawm, nyob rau hauv tas li ntawd mus rau saum toj, muaj ib tug ntau ntawm tej yam uas tej zaum yuav tsum tau ib tug cov ntaub ntawv compression txheej txheem nyob rau hauv thiaj li yuav txo nws volume, tab sis cov no yog cov feem ntau niaj hnub no.

Yuav ua li cas yuav ua tau kuv hlob cov ntaub ntawv?

Niaj hnub no, muaj ntau yam ntawm txoj kev ntawm cov ntaub ntawv compression, tab sis lawv muab faib ua ob lub ntsiab pawg - qhov no compression uas muaj tej yam losses, raws li zoo raws li lossless compression.

Siv tus tom kawg pab pawg neeg ntawm txoj kev yog yam thaum cov ntaub ntawv yuav tsum rov qab nrog tsis tshua muaj neeg siab precision, mus txog ib me ntsis. Qhov no mus kom ze yog tsuas yam nyob rau hauv lub rooj plaub thaum lub compression yog ua los ntawm ib tug ntawv nyeem daim ntawv no.

Nws yog ib nqi sau cia hais tias nyob rau hauv tej lub sijhawm yuav tsis muaj nyob rau hauv lub tshaj plaws yog reconstruction ntawm compressed ntaub ntawv li muab rau cov kev siv ntawm tej algorithms, nyob rau hauv uas lub disk cov ntaub ntawv compression yog nqa tawm nrog rau tej kev piam sij. Qhov kom zoo dua ntawm lossy compression yog hais tias qhov no technology yog ntau npaum li cas yooj yim rau siv, thiab muab lub siab tshaj plaws tau degree ntawm archiving.

Lossy compression

Algorithms rau cov ntaub ntawv compression nrog losses muab ib qho kev txiav txim ntawm qhov ntau zoo dua compression thaum tswj txaus zoo ntxiv. Nyob rau hauv Feem ntau, cov kev siv ntawm tej algorithms yog nqa tawm mus hlob lub analog cov ntaub ntawv, xws li tag nrho cov hom ntawm cov dluab los yog suab. Nyob rau hauv tej lub sijhawm, cov ntaub ntawv extracted tej zaum yuav txawv heev los ntawm cov thawj ntaub ntawv, tab sis rau cov tib neeg qhov muag los yog lub pob ntseg yog zoo indistinguishable.

lossless

Compression algorithms ntaub ntawv lossless muab cov tshaj plaws yog cov ntaub ntawv rov qab, precluding tej tsis compressed ntaub ntawv. Txawm li cas los, nws yog tsim nyog los raug to taub qhov tseeb hais tias nyob rau hauv cov ntaub ntawv no yog muab tsis zoo li cov ntaub ntawv compression.

Universal txoj kev

Nyob rau hauv tas li ntawd, muaj ib tug tej yam muaj pes tsawg tus ntawm universal txoj kev, uas ua rau zoo cov ntaub ntawv compression txheej txheem los mus txo lub chaw nyob los ntawm nws. Nyob rau hauv Feem ntau, koj muaj peev xwm xaiv tag nrho cov peb lub ntsiab yees:

• Hloov kwj. Nyob rau hauv cov ntaub ntawv no, qhov kev piav qhia ntawm ib tug tshiab tuaj uncompressed ntaub ntawv los ntawm twb ua ntaub ntawv, lub xam yog tsis nqa tawm tej qhov muaj tseeb, thiab encodes rau cov cim ntawm lub hauv paus ntawm tsuas yog cov ntaub ntawv uas tau raug tej yam kev kho mob.
• Statistical compression. Qhov no cov ntaub ntawv compression txheej txheem los mus txo nws nyob disk qhov chaw yog faib mus ua ob pawg ncua - adaptive thiab modular txoj kev. Coj kev xaiv muab muab xam rau ntawm lub probabilities rau tej ntaub ntawv tshiab rau cov ntaub ntawv uas yog tau tiav nyob rau hauv lub encoding txheej txheem. Nyob rau hauv kev, xws txoj kev yuav tsum tau muaj xws li variants ntawm ntau yam coj algorithms Shannon-Fano thiab Huffman. Thaiv algorithm muab cais vyschityvanie txhua ntaub ntawv tsev raws li los ntawm kev ntxiv mus rau lub compressed block.
• Unit hloov dua siab tshiab. Khoom ntaub ntawv no yuav muab faib mus rau hauv ob peb blocks, thiab tom qab no tshwm sim ib transformation. Nyob rau hauv cov ntaub ntawv no, nws yuav tsum tau muab sau tseg tias tej txoj kev, tshwj xeeb tshaj yog cov neeg uas yog raws li nyob rau hauv lub transposition ntawm ob peb chav nyob, tej zaum yuav kawg ua rau ib tug tseem ceeb yuav txo tau nyob rau hauv lub ntim ntawm compressed ntaub ntawv. Txawm li cas los, koj yuav tsum kom zoo zoo to taub hais tias tom qab qhov kev kho no, nws thiaj li muaj ib tug tseem ceeb kev txhim kho nyob rau hauv cov ntaub ntawv cov qauv, uas tus cwj pwm ntawm tom ntej compression los ntawm lwm cov algorithms siv ntau npaum li cas sai sai thiab yooj yim.

Compression thaum luam

Ib tug ntawm cov tseem ceeb tshaj plaws Cheebtsam ntawm lub backup yog ib tug ntaus ntawv los ntawm cov uas yuav tawm mus rau yuav tsum tau siv cov ntaub ntawv. Qhov ntau ntaub ntawv uas koj yuav tsiv mus nyob, qhov ntau volume tus ntaus ntawv koj yuav tsum tau siv. Txawm li cas los, Yog hais tias koj muaj cov ntaub ntawv compression txheej txheem yuav tsum nqa tawm, ces qhov teeb meem uas tsis muaj ntawm qhov chaw yog tsis zoo li mus nyob twj ywm yam rau koj.

Yog vim li cas ua tau nws?

Cov tau ntawm cov ntaub ntawv compression thaum lub sij hawm backups yuav txo tau lub sij hawm nws yuav tsim nyog los luam cov tsim nyog cov ntaub ntawv, thiab nyob rau tib lub sij hawm kom ua tau hauj lwm zoo nyiaj ntawm qhov chaw dawb rau tus tsav. Nyob rau hauv lwm yam lus, thaum uas siv cov compression cov ntaub ntawv yuav tsum tau theej rau ib tug ntau npaum li cas compact thiab ceev ceev, thiab koj yuav txuag koj cov nyiaj thiab tej nyiaj txiag, uas tau yuav tsum tau mus yuav dua cia ntim. Ntawm lwm yam, nqa tawm cov ntaub ntawv compression, koj kuj txiav lub sij hawm yuav tsum tau rau kev thauj mus los ntawm tag nrho cov ntaub ntawv nyob rau hauv lub neeg rau zaub mov, los yog luam lawv lub network.

Cov ntaub ntawv compression rau backup yuav tsum tau nyob rau hauv ib los yog ntau tshaj cov ntaub ntawv - nyob rau hauv cov ntaub ntawv no, txhua yam yuav yog nyob ntawm seb dab tsi zoo ntawm qhov kev pab cuam ua koj siv li cas thiab cov lus qhia yog compressed.

Thaum xaiv ib lub cuab tam, nco ntsoov mus saib nyob rau raws li qhov uas qhov kev pab cuam muaj peev xwm hlob cov ntaub ntawv koj tau xaiv. Nws nyob rau ntawm lub hom ntawm cov ntaub ntawv, uas lub compression efficiency ntawm phau ntawv cov ntaub ntawv yuav ua tau ntau tshaj li 90%, thaum cov duab compression yuav zoo tsis tshaj 5%.