Sekundarni jezik: |
Angleški jezik |
Sekundarni naslov: |
Stability test of digital camera inner orienation parameters |
Sekundarni povzetek: |
Consumer grade digital cameras can be fully suitable for some of the photogrammetric tasks. To use this kind of cameras in photogrammetry, you need to know their inner orientation parameters. Procedure that gives us this information, is called calibration. There is a lot of different camera calibration methods. Regarding to their inner orientation being unstable, the calibratrion method using 2D test field, is very appropriate to calibrate consumer grade digital cameras. This method enables us to calibrate camera almost every time and everywhere. I used 2D test field calibration method developed by Zhang (1998) that is basic for calibration computation in Modifoto software (Grigillo, 2003). This method needs at least three photos of test field that must not be perspectively the same. Test field is made of flat plate (A2 size) with grid of dots with known coordinates. I tested digital SLR camera Nikon D70 with zoom lenses. I tried to find out the minimal number of images, including their proper orientation, that is needed to reliably compute inner orientation parameters. I compared results computed from different image combinations. Considering right images orientation, four images are enough to get reliable results. In second analysis i tried to simulate conditions that can afect camera during fieldwork. I find out that changes of inner orientation parameters through time are minimal. I also made an analysis about influence of inner orientation parameters changes on photogrammetric restitution results. With careful use of properly calibrated camera, changes of parameters that can appear (talking for used camera and method) don't have significant influence on the results. |
Sekundarne ključne besede: |
geodesy;graduation thesis;inner orientation;digital camera;camera calibration;inner orientation stability; |
Vrsta datoteke: |
application/pdf |
Vrsta dela (COBISS): |
Diplomsko delo |
Komentar na gradivo: |
Univ. v Ljubljani, Fak. za gradbeništvo in geodezijo |
Strani: |
XI, 58 str., pril. |
Vrsta dela (ePrints): |
thesis |
Naslov (ePrints): |
Stability test of digital camera inner orienation parameters |
Ključne besede (ePrints): |
notranja orientacija;digitalni fotoaparat;kalibracija fotoaparata;stabilnost notranje orientacije |
Ključne besede (ePrints, sekundarni jezik): |
inner orientation;digital camera;camera calibration;inner orientation stability |
Povzetek (ePrints): |
Amaterski digitalni fotoaparati lahko predstavljajo povsem uporabno orodje za določene fotogrametrične namene. Za takšno uporabo je treba poznati elemente notranje orientacije fotoaparata. Postopek, s katerim jih pridobimo, imenujemo kalibracija. Obstaja veliko različnih metod kalibracije. Zaradi nestabilnosti notranje orientacije amaterskih fotoaparatov, je za njihovo kalibracijo zelo primerna metoda z uporabo ravninskega testnega polja. Metoda nam omogoča kalibracijo praktično kjerkoli in kadarkoli na terenu. V nalogi sem uporabljal metodo ravninskega testnega polja, ki jo je razvil Zhang (1998) in je osnova za kalibracijo v programskem paketu Modifoto (Grigillo, 2003). Metoda omogoča izračun parametrov notranje orientacije na podlagi perspektivno različnih posnetkov testnega polja, katerega predstavlja na ploščo (velikost A2) nanešena mreža točk z znanimi koordinatami. Testiral sem digitalni zrcalno refleksni fotoaparat Nikon D70 z objektivom s spremenljivo goriščnico. Želel sem ugotoviti minimalno število ter ustrezno orientacijo posnetkov za zanesljivo določitev parametrov notranje orientacije. Ob primerjavi rezultatov kalibracije dobljenih z različnimi kombinacijami posnetkov testnega polja ugotovimo, da ob strogem upoštevanju orientacije posnetkov, za zanesljivo kalibracijo zadostujejo štirje posnetki. V drugem delu sem ob simulaciji terenskih pogojev (vplivov) prišel do ugotovitve, da so časovne spremembe elementov notranje orientacije minimalne. V tretjem delu pa sem ugotavljal vpliv sprememb notranje orientacije na rezultate fotogrametričnega izvrednotenja. Rezultati so pokazali, da ob pazljivem ravnanju s fotoaparatom in ustrezni izvedbi kalibracije, morebitne spremembe notranje orientacije, pri uporabljeni metodi in fotoaparatu, bistveno ne vplivajo na rezultat . |
Povzetek (ePrints, sekundarni jezik): |
Consumer grade digital cameras can be fully suitable for some of the photogrammetric tasks. To use this kind of cameras in photogrammetry, you need to know their inner orientation parameters. Procedure that gives us this information, is called calibration. There is a lot of different camera calibration methods. Regarding to their inner orientation being unstable, the calibratrion method using 2D test field, is very appropriate to calibrate consumer grade digital cameras. This method enables us to calibrate camera almost every time and everywhere. I used 2D test field calibration method developed by Zhang (1998) that is basic for calibration computation in Modifoto software (Grigillo, 2003). This method needs at least three photos of test field that must not be perspectively the same. Test field is made of flat plate (A2 size) with grid of dots with known coordinates. I tested digital SLR camera Nikon D70 with zoom lenses. I tried to find out the minimal number of images, including their proper orientation, that is needed to reliably compute inner orientation parameters. I compared results computed from different image combinations. Considering right images orientation, four images are enough to get reliable results. In second analysis i tried to simulate conditions that can afect camera during fieldwork. I find out that changes of inner orientation parameters through time are minimal. I also made an analysis about influence of inner orientation parameters changes on photogrammetric restitution results. With careful use of properly calibrated camera, changes of parameters that can appear (talking for used camera and method) don't have significant influence on the results. |
Ključne besede (ePrints, sekundarni jezik): |
inner orientation;digital camera;camera calibration;inner orientation stability |
ID: |
8309675 |