Kawm Txog Cov Khoom Siv Uas Siv Tau Licas Hauv Digital
Cov khoom siv hauv cov koos pij tawj kom muab cov ntaub ntawv me me ua ib hom lus uas tus neeg siv tau nyeem. Raws li cov khoom me me yog cov siv los siv hauv koj lub computer, lawv siv cov duab digital los yees duab.
Dab tsi yog ib lub ntsis?
Ib "ntsis" yog ib lub sij hawm pib siv hauv computer lub tswv yim, qhov twg nws sawv rau "binary device", thiab yog hais txog qhov tsawg tshaj plaws daim ntawv xov xwm. Nws muaj nuj nqis ntawm 0 los sis 1.
Nyob hauv digital photography, 0 muab rau dub thiab 1 mus dawb.
Nyob rau hauv binary lus (puag-2), "10" yog sib npaug li 2 hauv puag-10, thiab "101" yog sib npaug li 5 hauv puag-10. (Yog xav paub ntxiv txog kev hloov cov leb-2 naj npawb los luj-10, mus saib hauv website ntawm unitconversion.org.)
Daim Ntawv Cov Ntaub Ntawv Li Cas
Cov neeg siv digital editing cov kev pab cuam, xws li Adobe Photoshop, yuav paub txog cov nqi sib txawv me ntsis. Ib qho ntawm ntau tshaj yog 8-ntsis duab, uas muaj 256 muaj tones, xws li "00000000" (tus nqi naj npawb 0 los yog dub) mus rau "11111111" (tus nqi naj npawb 255 los yog dawb).
Daim ntawv ceeb toom hais tias muaj 8 tus lej nyob rau txhua qhov ntawm cov kab ntawv. Qhov no yog vim 8 khoom sib npaug ib byte thiab ib byte tuaj yeem sawv cev 256 txawv xeev (los yog xim). Vim li no, los ntawm kev hloov ua ke ntawm cov 1 thiab 0 tus me ntsis sib lawv liag, lub computer muaj peev xwm tsim ib qho ntawm 256 variants ntawm cov xim (2 ^ 8th fais fab - '2' los ntawm binary code ntawm 1's thiab 0's).
To taub 8-ntsis, 24-ntsis, thiab 12- lossis 16-ntsis
JPEG dluab feem ntau hu ua cov duab 24-ntsis. Qhov no yog vim hais tias hom ntawv no tuaj yeem khaws txog li 8 khoom ntawm cov ntaub ntawv nyob rau hauv txhua ntawm lawv qhov xim peb (RGB los yog xim liab, ntsuab, thiab xiav).
Siab me ntsis nqi xws li 12- los sis 16-ntsis siv ntau DSLRs los tsim ntau ntau yam xim ntawm cov xim. Ib cov duab 16-ntsis yuav muaj 65,653 theem ntawm cov ntaub ntawv xim (2 ^ 16th zog) thiab 12-ntsis duab yuav muaj 4,096 qib (2 ^ 12th zog)
DSLRs siv feem ntau ntawm cov tones nyob rau ntawm qhov chaw nres tsheb, uas yoojyim heev ob peb tones rau qhov tsaus ntuj nres (qhov twg tib neeg lub qhov muag yog nyob rau hauv nws feem ntau rhiab). Txawm tias muaj 16-ntsis duab, piv txwv li, tsuas yog muaj 16 tones los piav txog qhov tsaus ntuj nti hauv kev yees duab. Lub teeb ci ntsa iab, nyob rau hauv kev sib piv, yuav muaj 32,768 tones!
Daim Ntawv Qhia Txog Luam Ntawv Dub thiab Dawb Duab
Qhov nruab nrab inkjet luam ntawv ua haujlwm rau lub 8-ntsis nplua thiab. Thaum luam tawm dub thiab dawb cov duab ntawm koj cov inkjet, nco ntsoov tsis muab nws los luam tawm tsuas yog siv cov xim dub (grayscale luam ntawv).
Qhov no yog ib txoj kev zoo los txuag cov cwj mem thaum luam tawm ntawv, tab sis nws yuav tsis tsim ib daim duab zoo. Ntawm no yog vim li cas ...
Qhov nruab nrab lub tshuab luam ntawv muaj ib qho, tej zaum 2, dub kua roj cartridges thiab 3 xim cartridges (hauv CMYK). Lub koos pis tawj muab cov ntaub ntawv ntawm ib daim duab luam tawm uas siv cov 256 cov kab txawv ntawm cov xim.
Yog tias peb cia siab rau cov dub cwj mem kua cartridges xwb los daws qhov ntawd, cov ntsiab lus ntawm daim duab yuav poob thiab gradients yuav tsis muab luam tawm kom raug. Nws tsuas tuaj yeem ua tsis tau 256 tus kabmob uas siv ib daim cartridge nkaus xwb.
Txawm hais tias dub thiab dawb duab yog qhov tsis muaj xim, nws tseem cia siab rau cov kev nplua-tuned 8-ntsis xim raws rau tag nrho cov tones sib txawv ntawm dub, grey, thiab dawb.
Qhov kev tso siab ntawm cov xim raws cai yog ib qho tseem ceeb rau cov kws yees duab kom to taub yog tias lawv xav tau ib daim duab nrog cov duab dub thiab dawb uas tau ua los ntawm cov duab thiab ntawv.