Data Compression vs Data Encryption
Cov ntaub ntawv compression yog cov txheej txheem ntawm kev txo qhov loj ntawm cov ntaub ntawv. Nws siv cov txheej txheem encoding, uas encodes cov ntaub ntawv siv tsawg tus lej ntawm cov ntaub ntawv qub. Encryption kuj yog txheej txheem ntawm kev hloov cov ntaub ntawv uas siv hauv cryptography. Nws hloov cov ntaub ntawv qub rau hauv hom ntawv uas tuaj yeem nkag siab los ntawm ib tog neeg uas muaj cov ntaub ntawv tshwj xeeb (hu ua tus yuam sij). Lub hom phiaj ntawm encryption yog khaws cov ntaub ntawv zais ntawm ob tog uas tsis muaj kev tso cai los saib cov ntaub ntawv.
Data Compression yog dab tsi?
Cov ntaub ntawv compression yog ib txoj hauv kev hloov cov ntaub ntawv nrog kev mob siab ntawm kev txo nws qhov loj. Qhov no muaj txiaj ntsig zoo vim tias nws tso cai txuag cov peev txheej xws li chaw cia khoom thiab bandwidth (thaum hloov cov ntaub ntawv). Nws siv txoj kev encoding uas yuav txo cov nqi ntawm cov khoom siv los khaws cov ntaub ntawv ntau dua li tus sawv cev qub. Thaum siv cov ntaub ntawv compressed, lawv yuav tsum tau decompressed ua ntej. Thaum tsim cov ntaub ntawv compression tswvyim, ib tug yuav tsum xav txog tej yam tseem ceeb xws li theem ntawm compression yuav tsum tau, tus nqi ntawm distortion qhia los ntawm compression scheme thiab cov kev siv computer thiab hardware yuav tsum tau compression thiab decompress cov ntaub ntawv. Tshwj xeeb tshaj yog, thaum nws los txog video decompression, tshwj xeeb kho vajtse yuav tsum tau decompress tus kwj ceev txaus kom qhov saib tsis cuam tshuam. Nrog kev yees duab, decompressing ua ntej tes yuav tsis yog ib qho kev xaiv vim nws yuav xav tau qhov chaw cia loj.
Data Encryption yog dab tsi?
Kev nkag mus yog ib txoj hauv kev hloov cov ntaub ntawv nrog kev mob siab rau khaws cia tsis pub leejtwg paub. Encryption siv lub algorithm hu ua cipher los encrypt cov ntaub ntawv thiab nws tuaj yeem decrypted tsuas yog siv tus yuam sij tshwj xeeb. Cov ntaub ntawv encrypted yog hu ua ciphertext thiab cov txheej txheem ntawm kev tau txais cov ntaub ntawv qub (plaintext) los ntawm ciphertext hu ua decryption. Kev encryption yog tshwj xeeb yuav tsum tau thaum sib txuas lus nyob rau hauv ib tug tsis ntseeg nruab nrab xws li internet, qhov twg cov ntaub ntawv yuav tsum tau kev tiv thaiv los ntawm lwm tus neeg sab nrauv. Niaj hnub nimno encryption txoj kev tsom mus rau kev tsim encryption algorithms (ciphers) uas nyuaj rau tawg los ntawm tus yeeb ncuab vim yog kev suav hardness (yog li ntawd tsis tuaj yeem tawg los ntawm cov tswv yim txhais tau tias). Ob txoj hauv kev siv encryption yog Symmetric key encryption thiab Public-key encryption. Hauv Symmetric key encryption, ob tus xa thiab tus txais tau sib koom tib tus yuam sij siv los encrypt cov ntaub ntawv. Hauv Public-key encryption, siv ob qhov sib txawv tab sis muaj feem xyuam nrog lej.
Dab tsi yog qhov sib txawv ntawm Cov Ntaub Ntawv Compression thiab Data Encryption?
Txawm hais tias ob qho tib si cov ntaub ntawv compression thiab encryption yog txoj hauv kev uas hloov cov ntaub ntawv mus rau lwm hom, cov golas sim ua kom tiav los ntawm lawv txawv. Cov ntaub ntawv compression yog ua tiav nrog kev mob siab ntawm kev txo qhov loj ntawm cov ntaub ntawv, thaum encryption yog ua kom cov ntaub ntawv zais cia los ntawm peb tog. Cov ntaub ntawv encrypted tsis tuaj yeem decrypted yooj yim. Nws yuav tsum muaj cov ntaub ntawv tshwj xeeb hu ua tus yuam sij. Uncompressing compressed cov ntaub ntawv tsis xav tau cov kev paub tshwj xeeb (xws li tus yuam sij), tab sis nws yuav xav tau qee qhov tshwj xeeb kho vajtse nyob ntawm hom ntaub ntawv.
