Amasu e-Photogrammetry ku-Archaeological Documentation
Ukubhala imibhalo kungenye yezigaba ezibaluleke kakhulu ocwaningweni lwezinto zakudala. Konke ukutholwa—kusukela ezintweni ezincane kanye nezici ze-stratigraphic kuya ezakhiweni zasendulo—kuhlukile futhi ngokuvamile akunakuphindwa ngemva kokumba. Ngakho-ke, abavubukuli badinga izindlela zokuqopha ezinembile, ezinemininingwane, nezinomthwalo wemfanelo. Emashumini eminyaka amuva nje, i-photogrammetry ivele njengendlela ehamba phambili yokubhala phansi izindawo nezinto zezinto zakudala. Ngokusebenzisa izithombe ezithathwe ngezindlela ezahlukene, i-photogrammetry ingakhiqiza amamodeli aqondile anezinhlangothi ezintathu (3D), aphelele ngokuthungwa okubonakalayo. Lesi sihloko sixoxa ngemibono eyisisekelo, izigaba zomsebenzi, izinzuzo, kanye nezinselele ze-photogrammetry emibhalweni yezinto zakudala.
Ukuqonda i-Photogrammetry nokuthi isebenza kanjani
I-Photogrammetry iyindlela yokulinganisa nokwenza imodeli yezinto ngokusekelwe ezithombeni. Isimiso sayo esiyinhloko ukwakha kabusha izimo ze-3D kusukela ochungechungeni lwezithombe ze-2D ezihambisanayo. Isofthiwe isesha amaphuzu avamile ezithombeni eziningi (ukufanisa izici), bese ibala izikhundla zekhamera kanye ne-geometry yezinto isebenzisa unxantathu. Imiphumela ingaba amafu aqinile (iqoqo lamaphuzu aqinile), ama-meshe (ubuso obune-polygonal), kanye namamephu okuthungwa (izingqimba zokuthungwa).
Esimweni sezinto zakudala, i-photogrammetry iyindlela engonakalisi futhi ingasetshenziswa kokubili ensimini (izindawo ezivulekile, izakhiwo, ukumba) kanye naselabhorethri (izinto zobuciko, amathambo, izitsha zobumba, imibhalo eqoshiwe). Ukuhlanganiswa kwedatha ebonakalayo neyejiyometri kwenza kube usizo kakhulu ekuhlaziyeni nasekushicileleni.
Kungani i-Photogrammetry ibalulekile ku-Archaeology?
I-Photogrammetry isithandwa kakhulu ngoba ingahlangabezana nezidingo zemibhalo yemivubukulo, edinga kokubili ukunemba nokusebenza kahle. Izindlela zokurekhoda zendabuko ezifana nemidwebo yesandla, ukulinganisa ngesandla, kanye nezithombe ezivamile zisabalulekile, kodwa zinemikhawulo: zidla isikhathi, kunzima ukuthwebula izimo eziyinkimbinkimbi, futhi ngokuvamile azinele ekuhlaziyweni okuningiliziwe kwendawo.
Ngokusebenzisa i-photogrammetry, abavubukuli bangenza okulandelayo:
1. Qopha ngokushesha izimo zendawo ngaphambi kokuba izingqimba zimbiwe zijule.
2. Ikhiqiza imodeli ye-3D engalinganiswa, ukuze amabanga, izindawo kanye nomthamo kungabalwa kabusha nganoma yisiphi isikhathi.
3. Dala izingobo zomlando zedijithali ezihlala njalo, eziwusizo ekulondolozweni nasekucwaningweni kabusha.
4. Khulisa ukucaca kwesayensi, ngoba idatha ingabiwa ukuze kuqinisekiswe.
Izigaba Zokusetshenziswa Kwe-Photogrammetry Ensimini
I-Photogrammetry ezindaweni zemivubukulo ngokuvamile ilandela izigaba ezilandelayo.
1. Ukuhlela Nokulungiselela
Ngaphambi kokudubula, ithimba lidinga ukunquma izinhloso: ukuthi lifuna yini ukubhala phansi indawo yokumba, izici ezithile (isib., phansi, izindonga, amathuna), noma indawo yendawo. Ukuhlela kuhlanganisa ukunquma ubukhulu, ukulungiswa okudingekayo, kanye nezimo zokukhanya.
Kubalulekile futhi ukulungiselela izindawo zokulawula, njengezindawo zokulawula umhlaba (Ground Control Points - GCPs) noma izikali zokulinganisa. Ama-GCP alinganiswa nge-GPS ehlukile noma isiteshi esiphelele azothuthukisa ukunemba kwe-georeferencing kwemodeli ye-3D.
2. Ukuthwebula Izithombe (Ukutholwa Kwedatha)
Ikhwalithi yemodeli incike kakhulu kwikhwalithi yesithombe. Ezinye zezimiso eziyinhloko ze-photogrammetry yilezi:
– Ukweqana okuphezulu: cishe u-70–80% phakathi kwezithombe.
– Ama-engeli ahlukahlukene okudubula: izithombe ezivela phezulu nasohlangothini ukuze imininingwane yesimo ithathwe.
– Ukugxila kanye nokuvezwa okuhlala njalo: gwema izithombe ezifiphele noma ezimnyama kakhulu/ezikhanyayo.
– Ukukhanya okuzinzile: izithunzi ezibukhali zingenza ukwakha kabusha kube nzima; ukudubula ekukhanyeni okulinganayo kuvame ukuba ngcono kakhulu.
Ensimini, amakhamera angaphathwa ngesandla, afakwe ku-tripod, noma asetshenziswe nama-drones ezindaweni ezinkulu. Ukuze kubhalwe phansi ukumba komhlaba, izithombe ze-nadir (eziqondile ezivela phezulu) zivame kakhulu.
3. Ukucubungula ku-Software
Uma izithombe seziqoqiwe, idatha icutshungulwa kusetshenziswa isofthiwe ye-photogrammetry (isb., i-Agisoft Metashape, i-RealityCapture, noma isofthiwe yomthombo ovulekile njenge-Meshroom). Izinyathelo zokucubungula zivame ukufaka:
– Qondanisa Izithombe: inquma indawo yekhamera futhi idale ifu eliyiphuzu elincane.
– Yakha Ifu Eliminyene: yakha iqoqo lamaphuzu aminyene.
– Yakha i-Mesh: yakha ubuso bemodeli.
– Ukwakheka Kwakhe: kunamathisela ukuthungwa kwesithombe ebusweni.
– Ukulinganisa/Ukulinganisa i-Georeferencing: faka isikali noma izixhumanisi ze-GCP ukuze imodeli ifane nosayizi wangempela.
Imiphumela yokugcina ingathunyelwa kumafomethi ahlukahlukene (i-OBJ, i-FBX, i-LAS/PLY, i-GeoTIFF orthomosaic) ukuze ihlaziywe kabanzi.
4. Imikhiqizo Yemibhalo: Ama-Orthophotos, Amamodeli e-3D, kanye Namamephu
I-Photogrammetry ikhiqiza umkhiqizo owusizo kakhulu, okuhlanganisa:
– I-Orthophoto/i-orthomosaic: isithombe esibukwa phezulu esilungisiwe ngenxa yokuphambuka kombono futhi singasetshenziswa njengemephu.
– Amamodeli e-3D anesimo: afanelekela ukubonakala kanye nokuhlaziywa kwesimo.
– Imodeli Yokuphakama Kwedijithali (i-DEM): imodeli yokuphakama esiza ezifundweni ze-micro-topographic endaweni.
Lo mkhiqizo ungahlanganiswa ne-GIS ukuze kuhlaziywe indawo, isibonelo ukumaka ukusatshalaliswa kokutholakele noma ukuqonda ubudlelwano phakathi kwezici.
I-Photogrammetry yezinto zobuciko kanye nezinto ezincane ezitholakele
Ngaphandle kwezindawo, i-photogrammetry isebenza kahle kakhulu ezintweni ezincane ezifana nobumba, amathuluzi amatshe, izithombe eziqoshiwe, noma imibhalo eqoshiwe. Izithombe zivame ukuthathwa endaweni elawulwayo enesizinda esingathathi hlangothi, ukukhanya okusabalalayo, kanye netafula elijikelezayo ukuqinisekisa ukuthi ama-engeli alinganayo.
Inzuzo yayo eyinhloko ikhono lokuthwebula imininingwane emincane, njengezimpawu zokuguga, imihlobiso, noma imifantu. Amamodeli ezinto zobuciko ze-3D angasetshenziswa futhi uku:
- Ukwakhiwa kabusha kwedijithali kwezingcezu,
- Ukwenza amakhophi ngokuphrinta kwe-3D,
– Imibukiso ebonakalayo eminyuziyamu.
Izinzuzo ze-Photogrammetry Uma Ziqhathaniswa Nezinye Izindlela
I-Photogrammetry ivame ukuqhathaniswa nokuskena nge-laser (i-LiDAR/terrestrial laser scanning). Zombili zingakhiqiza amamodeli e-3D, kodwa i-photogrammetry inezinzuzo eziningana:
– Izindleko eziphansi kakhulu, ngoba kudinga ikhamera nesofthiwe kuphela.
– Ukuthungwa okubonakalayo kungokoqobo kakhulu, ngoba kusebenzisa izithombe.
- Iyakwazi ukushintshashintsha ngezikali ezahlukahlukene, kusukela ezintweni zobuciko kuya ezindaweni ezinama-drones.
Kodwa-ke, ukuskena nge-laser kuyaphumelela ezimweni eziphansi futhi kungaqina kakhulu ezindaweni ezingathungwanga kahle. Empeleni, amaphrojekthi amaningi ezinto zakudala ahlanganisa lokhu kokubili.
Izinselele kanye nokulinganiselwa
Nakuba kuwusizo kakhulu, i-photogrammetry inezinselele okudingeka zilindelwe:
1. Izindawo ezifanayo noma ezikhanyayo (isib. itshe elicwebezelayo, insimbi ecwebezelayo) kunzima ukuzivuselela ngenxa yokuntuleka kwamaphuzu avelele.
2. Izitshalo nezinto ezihambayo (abantu abadlulayo, abaphehla amaqabunga) zingangenisa umsindo kumodeli.
3. Umthamo wekhompyutha: ukucubungula izithombe ezinekhwalithi ephezulu kudinga ikhompyutha ene-RAM ne-GPU eyanele.
4. Ukuphathwa kwedatha: amafayela ezithombe kanye nemiphumela yokucubungula ingaba mikhulu kakhulu, kudinga uhlelo lokugcina kanye nemethadatha ecocekile.
5. Ukunemba kuncike ekulawulweni kwesikali: ngaphandle kwama-GCP noma izilinganiso zesikali, imodeli ye-3D ingaba "yinhle" ngokubonakalayo kodwa ingasebenzi ezilinganisweni zesayensi.
Ngakho-ke, izindinganiso zokusebenza kwensimu, ukuqoshwa kwamapharamitha ekhamera, kanye nezinqubo zokulinganisa ukulawula kunconywa kakhulu.
Imiphumela Yokulondolozwa Nokusatshalaliswa Komphakathi
I-Photogrammetry ayizuzisi abacwaningi kuphela kodwa futhi nabalondolozi kanye nomphakathi. Amamodeli e-3D avumela ukuqapha umonakalo ngokuhamba kwesikhathi, isibonelo, emifanekisweni yethempeli egugile. Ngaphezu kwalokho, imiphumela ye-photogrammetry ingasetshenziswa ngezinjongo zemfundo, izinkambo zesayithi eziku-inthanethi, kanye nezinto zokubonisa ezisebenzisanayo. Ngakho-ke, i-photogrammetry isiza ukuhlanganisa ucwaningo lwezemfundo nezidingo zokulondolozwa kanye nokuxhumana nomphakathi.
Isiphetho
Amasu e-photogrammetry abe yithuluzi elibalulekile emibhalweni yesimanje yemivubukulo. Njengoba inekhono lokukhiqiza amamodeli e-3D anembile acebile ngemininingwane ebonakalayo, i-photogrammetry ithuthukisa ukuqoshwa, ukuhlaziywa, kanye nokugcinwa kwedatha yemivubukulo. Ngenkathi inemikhawulo—njengesidingo sokuhlanganisana okuphezulu, ukulawula isikali, kanye nokucutshungulwa kwedatha okudingakalayo—lezi zinselele zinganqotshwa ngokuhlela ngokucophelela kanye nezinqubo ezijwayelekile. Phakathi kwesidingo esikhulayo sokulondolozwa kanye nokufinyelela okukhulu kolwazi, i-photogrammetry inikeza abavubukuli indlela entsha yokurekhoda isikhathi esidlule ngokunemba okukhulu, ukucaca, kanye nefa lezingobo zomlando zedijithali zesikhathi eside.
Uma ufisa, ngingaguqula lesi sihloko sibe ngesezemfundo kakhulu (ngezingcaphuno kanye nohlu lwezincwadi), noma ngishintshe ukugxila kwaso kube yi-drone photogrammetry, imibhalo yokumba ye-stratigraphic, noma i-photogrammetry yezinto ezenziwe nge-museum.
