利用影像生产dsm的流程.pdf

利用影像生产dsm的流程

英文回答：

ToproduceaDigitalSurfaceModel(DSM)fromimagery,

severalstepsneedtobefollowed.Theprocessinvolves

extractingelevationinformationfromtheimagesand

creatinga3DrepresentationoftheEarthssurface.Letme

walkyouthroughthestepsinvolvedinthisprocess.

1.Imageacquisition:Thefirststepistoacquire

high-resolutionaerialorsatelliteimageryofthedesired

area.Theseimagesshouldhavesufficientoverlaptoensure

accuratereconstructionoftheterrain.

2.Imagepreprocessing:Beforeextractingelevation

information,theimagesneedtoundergopreprocessingsteps

suchasradiometricandgeometriccorrections.These

correctionsensurethattheimagesareproperlycalibrated

andaligned.

3.Imagematching:Inthisstep,thesoftwareanalyzes

theoverlappingareasoftheimagesandidentifiescommon

features.Thesefeaturescouldbepoints,lines,orareas

thatcanbematchedbetweenimages.Thesoftwarethen

calculatesthepositionandorientationofeachimage

relativetotheothers.

4.Denseimagematching:Oncetheinitialmatchingis

done,thesoftwareperformsdenseimagematchingto

generateapointcloud.Thispointcloudrepresentsthe3D

coordinatesofthematchedfeaturesintheimages.

5.Pointcloudfiltering:Thegeneratedpointcloudmay

containnoiseoroutliers.Toimprovetheaccuracyofthe

DSM,afilteringprocessisappliedtoremovethese

unwantedpoints.Thisfilteringcanbedonebasedon

variouscriteriasuchaselevation,density,orstatistical

analysis.

6.Surfacereconstruction:Afterfilteringthepoint

cloud,thenextstepistoreconstructthesurface.This

canbedoneusingvariousalgorithmssuchastriangulation

orgridinterpolation.Theresultisacontinuoussurface

representationoftheterrain.

7.DSMgeneration:Finally,theDSMisgeneratedby

extractingtheelevationvaluesfromthereconst