# # Author: Cunren Liang # Copyright 2015-present, NASA-JPL/Caltech # import os import glob import logging import datetime import numpy as np import isceobj import isceobj.Sensor.MultiMode as MultiMode from isceobj.Planet.Planet import Planet from isceobj.Alos2Proc.Alos2ProcPublic import runCmd from isceobj.Alos2Proc.Alos2ProcPublic import getBboxRdr from isceobj.Alos2Proc.Alos2ProcPublic import getBboxGeo logger = logging.getLogger('isce.alos2insar.runPreprocessor') def runPreprocessor(self): '''Extract images. ''' catalog = isceobj.Catalog.createCatalog(self._insar.procDoc.name) #find files #actually no need to use absolute path any longer, since we are able to find file from vrt now. 27-JAN-2020, CRL. #denseoffset may still need absolute path when making links self.masterDir = os.path.abspath(self.masterDir) self.slaveDir = os.path.abspath(self.slaveDir) ledFilesMaster = sorted(glob.glob(os.path.join(self.masterDir, 'LED-ALOS2*-*-*'))) imgFilesMaster = sorted(glob.glob(os.path.join(self.masterDir, 'IMG-{}-ALOS2*-*-*'.format(self.masterPolarization.upper())))) ledFilesSlave = sorted(glob.glob(os.path.join(self.slaveDir, 'LED-ALOS2*-*-*'))) imgFilesSlave = sorted(glob.glob(os.path.join(self.slaveDir, 'IMG-{}-ALOS2*-*-*'.format(self.slavePolarization.upper())))) firstFrameMaster = ledFilesMaster[0].split('-')[-3][-4:] firstFrameSlave = ledFilesSlave[0].split('-')[-3][-4:] firstFrameImagesMaster = sorted(glob.glob(os.path.join(self.masterDir, 'IMG-{}-ALOS2*{}-*-*'.format(self.masterPolarization.upper(), firstFrameMaster)))) firstFrameImagesSlave = sorted(glob.glob(os.path.join(self.slaveDir, 'IMG-{}-ALOS2*{}-*-*'.format(self.slavePolarization.upper(), firstFrameSlave)))) #determin operation mode masterMode = os.path.basename(ledFilesMaster[0]).split('-')[-1][0:3] slaveMode = os.path.basename(ledFilesSlave[0]).split('-')[-1][0:3] spotlightModes = ['SBS'] stripmapModes = ['UBS', 'UBD', 'HBS', 'HBD', 'HBQ', 'FBS', 'FBD', 'FBQ'] scansarNominalModes = ['WBS', 'WBD', 'WWS', 'WWD'] scansarWideModes = ['VBS', 'VBD'] scansarModes = ['WBS', 'WBD', 'WWS', 'WWD', 'VBS', 'VBD'] #usable combinations if (masterMode in spotlightModes) and (slaveMode in spotlightModes): self._insar.modeCombination = 0 elif (masterMode in stripmapModes) and (slaveMode in stripmapModes): self._insar.modeCombination = 1 elif (masterMode in scansarNominalModes) and (slaveMode in scansarNominalModes): self._insar.modeCombination = 21 elif (masterMode in scansarWideModes) and (slaveMode in scansarWideModes): self._insar.modeCombination = 22 elif (masterMode in scansarNominalModes) and (slaveMode in stripmapModes): self._insar.modeCombination = 31 elif (masterMode in scansarWideModes) and (slaveMode in stripmapModes): self._insar.modeCombination = 32 else: print('\n\nthis mode combination is not possible') print('note that for ScanSAR-stripmap, ScanSAR must be master\n\n') raise Exception('mode combination not supported') # pixel size from real data processing. azimuth pixel size may change a bit as # the antenna points to a different swath and therefore uses a different PRF. # MODE RANGE PIXEL SIZE (LOOKS) AZIMUTH PIXEL SIZE (LOOKS) # ------------------------------------------------------------------- # SPT [SBS] # 1.4304222392897463 (2) 0.9351804642158579 (4) # SM1 [UBS,UBD] # 1.4304222392897463 (2) 1.8291988125114438 (2) # SM2 [HBS,HBD,HBQ] # 2.8608444785794984 (2) 3.0672373839847196 (2) # SM3 [FBS,FBD,FBQ] # 4.291266717869248 (2) 3.2462615913656667 (4) # WD1 [WBS,WBD] [WWS,WWD] # 8.582533435738496 (1) 2.6053935830031887 (14) # 8.582533435738496 (1) 2.092362043327227 (14) # 8.582533435738496 (1) 2.8817632034495717 (14) # 8.582533435738496 (1) 3.054362492601842 (14) # 8.582533435738496 (1) 2.4582084463356977 (14) # WD2 [VBS,VBD] # 8.582533435738496 (1) 2.9215796012950728 (14) # 8.582533435738496 (1) 3.088859074497863 (14) # 8.582533435738496 (1) 2.8792293071133073 (14) # 8.582533435738496 (1) 3.0592146044234854 (14) # 8.582533435738496 (1) 2.8818767752199137 (14) # 8.582533435738496 (1) 3.047038521027477 (14) # 8.582533435738496 (1) 2.898816222039108 (14) #determine default number of looks: self._insar.numberRangeLooks1 = self.numberRangeLooks1 self._insar.numberAzimuthLooks1 = self.numberAzimuthLooks1 self._insar.numberRangeLooks2 = self.numberRangeLooks2 self._insar.numberAzimuthLooks2 = self.numberAzimuthLooks2 #the following two will be automatically determined by runRdrDemOffset.py self._insar.numberRangeLooksSim = self.numberRangeLooksSim self._insar.numberAzimuthLooksSim = self.numberAzimuthLooksSim self._insar.numberRangeLooksIon = self.numberRangeLooksIon self._insar.numberAzimuthLooksIon = self.numberAzimuthLooksIon if self._insar.numberRangeLooks1 == None: if masterMode in ['SBS']: self._insar.numberRangeLooks1 = 2 elif masterMode in ['UBS', 'UBD']: self._insar.numberRangeLooks1 = 2 elif masterMode in ['HBS', 'HBD', 'HBQ']: self._insar.numberRangeLooks1 = 2 elif masterMode in ['FBS', 'FBD', 'FBQ']: self._insar.numberRangeLooks1 = 2 elif masterMode in ['WBS', 'WBD']: self._insar.numberRangeLooks1 = 1 elif masterMode in ['WWS', 'WWD']: self._insar.numberRangeLooks1 = 2 elif masterMode in ['VBS', 'VBD']: self._insar.numberRangeLooks1 = 1 else: raise Exception('unknow acquisition mode') if self._insar.numberAzimuthLooks1 == None: if masterMode in ['SBS']: self._insar.numberAzimuthLooks1 = 4 elif masterMode in ['UBS', 'UBD']: self._insar.numberAzimuthLooks1 = 2 elif masterMode in ['HBS', 'HBD', 'HBQ']: self._insar.numberAzimuthLooks1 = 2 elif masterMode in ['FBS', 'FBD', 'FBQ']: self._insar.numberAzimuthLooks1 = 4 elif masterMode in ['WBS', 'WBD']: self._insar.numberAzimuthLooks1 = 14 elif masterMode in ['WWS', 'WWD']: self._insar.numberAzimuthLooks1 = 14 elif masterMode in ['VBS', 'VBD']: self._insar.numberAzimuthLooks1 = 14 else: raise Exception('unknow acquisition mode') if self._insar.numberRangeLooks2 == None: if masterMode in spotlightModes: self._insar.numberRangeLooks2 = 4 elif masterMode in stripmapModes: self._insar.numberRangeLooks2 = 4 elif masterMode in scansarModes: self._insar.numberRangeLooks2 = 5 else: raise Exception('unknow acquisition mode') if self._insar.numberAzimuthLooks2 == None: if masterMode in spotlightModes: self._insar.numberAzimuthLooks2 = 4 elif masterMode in stripmapModes: self._insar.numberAzimuthLooks2 = 4 elif masterMode in scansarModes: self._insar.numberAzimuthLooks2 = 2 else: raise Exception('unknow acquisition mode') if self._insar.numberRangeLooksIon == None: if masterMode in spotlightModes: self._insar.numberRangeLooksIon = 16 elif masterMode in stripmapModes: self._insar.numberRangeLooksIon = 16 elif masterMode in scansarModes: self._insar.numberRangeLooksIon = 40 else: raise Exception('unknow acquisition mode') if self._insar.numberAzimuthLooksIon == None: if masterMode in spotlightModes: self._insar.numberAzimuthLooksIon = 16 elif masterMode in stripmapModes: self._insar.numberAzimuthLooksIon = 16 elif masterMode in scansarModes: self._insar.numberAzimuthLooksIon = 16 else: raise Exception('unknow acquisition mode') #define processing file names self._insar.masterDate = os.path.basename(ledFilesMaster[0]).split('-')[2] self._insar.slaveDate = os.path.basename(ledFilesSlave[0]).split('-')[2] self._insar.setFilename(masterDate=self._insar.masterDate, slaveDate=self._insar.slaveDate, nrlks1=self._insar.numberRangeLooks1, nalks1=self._insar.numberAzimuthLooks1, nrlks2=self._insar.numberRangeLooks2, nalks2=self._insar.numberAzimuthLooks2) #find frame numbers if (self._insar.modeCombination == 31) or (self._insar.modeCombination == 32): if (self.masterFrames == None) or (self.slaveFrames == None): raise Exception('for ScanSAR-stripmap inteferometry, you must set master and slave frame numbers') #if not set, find frames automatically if self.masterFrames == None: self.masterFrames = [] for led in ledFilesMaster: frameNumber = os.path.basename(led).split('-')[1][-4:] if frameNumber not in self.masterFrames: self.masterFrames.append(frameNumber) if self.slaveFrames == None: self.slaveFrames = [] for led in ledFilesSlave: frameNumber = os.path.basename(led).split('-')[1][-4:] if frameNumber not in self.slaveFrames: self.slaveFrames.append(frameNumber) #sort frames self.masterFrames = sorted(self.masterFrames) self.slaveFrames = sorted(self.slaveFrames) #check number of frames if len(self.masterFrames) != len(self.slaveFrames): raise Exception('number of frames in master dir is not equal to number of frames \ in slave dir. please set frame number manually') #find swath numbers (if not ScanSAR-ScanSAR, compute valid swaths) if (self._insar.modeCombination == 0) or (self._insar.modeCombination == 1): self.startingSwath = 1 self.endingSwath = 1 if self._insar.modeCombination == 21: if self.startingSwath == None: self.startingSwath = 1 if self.endingSwath == None: self.endingSwath = 5 if self._insar.modeCombination == 22: if self.startingSwath == None: self.startingSwath = 1 if self.endingSwath == None: self.endingSwath = 7 #determine starting and ending swaths for ScanSAR-stripmap, user's settings are overwritten #use first frame to check overlap if (self._insar.modeCombination == 31) or (self._insar.modeCombination == 32): if self._insar.modeCombination == 31: numberOfSwaths = 5 else: numberOfSwaths = 7 overlapSubswaths = [] for i in range(numberOfSwaths): overlapRatio = check_overlap(ledFilesMaster[0], firstFrameImagesMaster[i], ledFilesSlave[0], firstFrameImagesSlave[0]) if overlapRatio > 1.0 / 4.0: overlapSubswaths.append(i+1) if overlapSubswaths == []: raise Exception('There is no overlap area between the ScanSAR-stripmap pair') self.startingSwath = int(overlapSubswaths[0]) self.endingSwath = int(overlapSubswaths[-1]) #save the valid frames and swaths for future processing self._insar.masterFrames = self.masterFrames self._insar.slaveFrames = self.slaveFrames self._insar.startingSwath = self.startingSwath self._insar.endingSwath = self.endingSwath ################################################## #1. create directories and read data ################################################## self.master.configure() self.slave.configure() self.master.track.configure() self.slave.track.configure() for i, (masterFrame, slaveFrame) in enumerate(zip(self._insar.masterFrames, self._insar.slaveFrames)): #frame number starts with 1 frameDir = 'f{}_{}'.format(i+1, masterFrame) os.makedirs(frameDir, exist_ok=True) os.chdir(frameDir) #attach a frame to master and slave frameObjMaster = MultiMode.createFrame() frameObjSlave = MultiMode.createFrame() frameObjMaster.configure() frameObjSlave.configure() self.master.track.frames.append(frameObjMaster) self.slave.track.frames.append(frameObjSlave) #swath number starts with 1 for j in range(self._insar.startingSwath, self._insar.endingSwath+1): print('processing frame {} swath {}'.format(masterFrame, j)) swathDir = 's{}'.format(j) os.makedirs(swathDir, exist_ok=True) os.chdir(swathDir) #attach a swath to master and slave swathObjMaster = MultiMode.createSwath() swathObjSlave = MultiMode.createSwath() swathObjMaster.configure() swathObjSlave.configure() self.master.track.frames[-1].swaths.append(swathObjMaster) self.slave.track.frames[-1].swaths.append(swathObjSlave) #setup master self.master.leaderFile = sorted(glob.glob(os.path.join(self.masterDir, 'LED-ALOS2*{}-*-*'.format(masterFrame))))[0] if masterMode in scansarModes: self.master.imageFile = sorted(glob.glob(os.path.join(self.masterDir, 'IMG-{}-ALOS2*{}-*-*-F{}'.format(self.masterPolarization.upper(), masterFrame, j))))[0] else: self.master.imageFile = sorted(glob.glob(os.path.join(self.masterDir, 'IMG-{}-ALOS2*{}-*-*'.format(self.masterPolarization.upper(), masterFrame))))[0] self.master.outputFile = self._insar.masterSlc self.master.useVirtualFile = self.useVirtualFile #read master (imageFDR, imageData)=self.master.readImage() (leaderFDR, sceneHeaderRecord, platformPositionRecord, facilityRecord)=self.master.readLeader() self.master.setSwath(leaderFDR, sceneHeaderRecord, platformPositionRecord, facilityRecord, imageFDR, imageData) self.master.setFrame(leaderFDR, sceneHeaderRecord, platformPositionRecord, facilityRecord, imageFDR, imageData) self.master.setTrack(leaderFDR, sceneHeaderRecord, platformPositionRecord, facilityRecord, imageFDR, imageData) #setup slave self.slave.leaderFile = sorted(glob.glob(os.path.join(self.slaveDir, 'LED-ALOS2*{}-*-*'.format(slaveFrame))))[0] if slaveMode in scansarModes: self.slave.imageFile = sorted(glob.glob(os.path.join(self.slaveDir, 'IMG-{}-ALOS2*{}-*-*-F{}'.format(self.slavePolarization.upper(), slaveFrame, j))))[0] else: self.slave.imageFile = sorted(glob.glob(os.path.join(self.slaveDir, 'IMG-{}-ALOS2*{}-*-*'.format(self.slavePolarization.upper(), slaveFrame))))[0] self.slave.outputFile = self._insar.slaveSlc self.slave.useVirtualFile = self.useVirtualFile #read slave (imageFDR, imageData)=self.slave.readImage() (leaderFDR, sceneHeaderRecord, platformPositionRecord, facilityRecord)=self.slave.readLeader() self.slave.setSwath(leaderFDR, sceneHeaderRecord, platformPositionRecord, facilityRecord, imageFDR, imageData) self.slave.setFrame(leaderFDR, sceneHeaderRecord, platformPositionRecord, facilityRecord, imageFDR, imageData) self.slave.setTrack(leaderFDR, sceneHeaderRecord, platformPositionRecord, facilityRecord, imageFDR, imageData) os.chdir('../') self._insar.saveProduct(self.master.track.frames[-1], self._insar.masterFrameParameter) self._insar.saveProduct(self.slave.track.frames[-1], self._insar.slaveFrameParameter) os.chdir('../') self._insar.saveProduct(self.master.track, self._insar.masterTrackParameter) self._insar.saveProduct(self.slave.track, self._insar.slaveTrackParameter) ################################################## #2. compute burst synchronization ################################################## #burst synchronization may slowly change along a track as a result of the changing relative speed of the two flights #in one frame, real unsynchronized time is the same for all swaths unsynTime = 0 #real synchronized time/percentage depends on the swath burst length (synTime = burstlength - abs(unsynTime)) #synTime = 0 synPercentage = 0 numberOfFrames = len(self._insar.masterFrames) numberOfSwaths = self._insar.endingSwath - self._insar.startingSwath + 1 for i, frameNumber in enumerate(self._insar.masterFrames): for j, swathNumber in enumerate(range(self._insar.startingSwath, self._insar.endingSwath + 1)): masterSwath = self.master.track.frames[i].swaths[j] slaveSwath = self.slave.track.frames[i].swaths[j] #using Piyush's code for computing range and azimuth offsets midRange = masterSwath.startingRange + masterSwath.rangePixelSize * masterSwath.numberOfSamples * 0.5 midSensingStart = masterSwath.sensingStart + datetime.timedelta(seconds = masterSwath.numberOfLines * 0.5 / masterSwath.prf) llh = self.master.track.orbit.rdr2geo(midSensingStart, midRange) slvaz, slvrng = self.slave.track.orbit.geo2rdr(llh) ###Translate to offsets #note that slave range pixel size and prf might be different from master, here we assume there is a virtual slave with same #range pixel size and prf rgoff = ((slvrng - slaveSwath.startingRange) / masterSwath.rangePixelSize) - masterSwath.numberOfSamples * 0.5 azoff = ((slvaz - slaveSwath.sensingStart).total_seconds() * masterSwath.prf) - masterSwath.numberOfLines * 0.5 #compute burst synchronization #burst parameters for ScanSAR wide mode not estimed yet if self._insar.modeCombination == 21: scburstStartLine = (masterSwath.burstStartTime - masterSwath.sensingStart).total_seconds() * masterSwath.prf + azoff #slave burst start times corresponding to master burst start times (100% synchronization) scburstStartLines = np.arange(scburstStartLine - 100000*masterSwath.burstCycleLength, \ scburstStartLine + 100000*masterSwath.burstCycleLength, \ masterSwath.burstCycleLength) dscburstStartLines = -((slaveSwath.burstStartTime - slaveSwath.sensingStart).total_seconds() * slaveSwath.prf - scburstStartLines) #find the difference with minimum absolute value unsynLines = dscburstStartLines[np.argmin(np.absolute(dscburstStartLines))] if np.absolute(unsynLines) >= slaveSwath.burstLength: synLines = 0 if unsynLines > 0: unsynLines = slaveSwath.burstLength else: unsynLines = -slaveSwath.burstLength else: synLines = slaveSwath.burstLength - np.absolute(unsynLines) unsynTime += unsynLines / masterSwath.prf synPercentage += synLines / masterSwath.burstLength * 100.0 catalog.addItem('burst synchronization of frame {} swath {}'.format(frameNumber, swathNumber), '%.1f%%'%(synLines / masterSwath.burstLength * 100.0), 'runPreprocessor') ############################################################################################ #illustration of the sign of the number of unsynchronized lines (unsynLines) #The convention is the same as ampcor offset, that is, # slaveLineNumber = masterLineNumber + unsynLines # # |-----------------------| ------------ # | | ^ # | | | # | | | unsynLines < 0 # | | | # | | \ / # | | |-----------------------| # | | | | # | | | | # |-----------------------| | | # Master Burst | | # | | # | | # | | # | | # |-----------------------| # Slave Burst # # ############################################################################################ ##burst parameters for ScanSAR wide mode not estimed yet elif self._insar.modeCombination == 31: #scansar is master scburstStartLine = (masterSwath.burstStartTime - masterSwath.sensingStart).total_seconds() * masterSwath.prf + azoff #slave burst start times corresponding to master burst start times (100% synchronization) for k in range(-100000, 100000): saz_burstx = scburstStartLine + masterSwath.burstCycleLength * k st_burstx = slaveSwath.sensingStart + datetime.timedelta(seconds=saz_burstx / masterSwath.prf) if saz_burstx >= 0.0 and saz_burstx <= slaveSwath.numberOfLines -1: slaveSwath.burstStartTime = st_burstx slaveSwath.burstLength = masterSwath.burstLength slaveSwath.burstCycleLength = masterSwath.burstCycleLength slaveSwath.swathNumber = masterSwath.swathNumber break #unsynLines = 0 #synLines = masterSwath.burstLength #unsynTime += unsynLines / masterSwath.prf #synPercentage += synLines / masterSwath.burstLength * 100.0 catalog.addItem('burst synchronization of frame {} swath {}'.format(frameNumber, swathNumber), '%.1f%%'%(100.0), 'runPreprocessor') else: pass #overwrite original frame parameter file if self._insar.modeCombination == 31: frameDir = 'f{}_{}'.format(i+1, frameNumber) self._insar.saveProduct(self.slave.track.frames[i], os.path.join(frameDir, self._insar.slaveFrameParameter)) #getting average if self._insar.modeCombination == 21: unsynTime /= numberOfFrames*numberOfSwaths synPercentage /= numberOfFrames*numberOfSwaths elif self._insar.modeCombination == 31: unsynTime = 0. synPercentage = 100. else: pass #record results if (self._insar.modeCombination == 21) or (self._insar.modeCombination == 31): self._insar.burstUnsynchronizedTime = unsynTime self._insar.burstSynchronization = synPercentage catalog.addItem('burst synchronization averaged', '%.1f%%'%(synPercentage), 'runPreprocessor') ################################################## #3. compute baseline ################################################## #only compute baseline at four corners and center of the master track bboxRdr = getBboxRdr(self.master.track) rangeMin = bboxRdr[0] rangeMax = bboxRdr[1] azimuthTimeMin = bboxRdr[2] azimuthTimeMax = bboxRdr[3] azimuthTimeMid = azimuthTimeMin+datetime.timedelta(seconds=(azimuthTimeMax-azimuthTimeMin).total_seconds()/2.0) rangeMid = (rangeMin + rangeMax) / 2.0 points = [[azimuthTimeMin, rangeMin], [azimuthTimeMin, rangeMax], [azimuthTimeMax, rangeMin], [azimuthTimeMax, rangeMax], [azimuthTimeMid, rangeMid]] Bpar = [] Bperp = [] #modify Piyush's code for computing baslines refElp = Planet(pname='Earth').ellipsoid for x in points: masterSV = self.master.track.orbit.interpolate(x[0], method='hermite') target = self.master.track.orbit.rdr2geo(x[0], x[1]) slvTime, slvrng = self.slave.track.orbit.geo2rdr(target) slaveSV = self.slave.track.orbit.interpolateOrbit(slvTime, method='hermite') targxyz = np.array(refElp.LLH(target[0], target[1], target[2]).ecef().tolist()) mxyz = np.array(masterSV.getPosition()) mvel = np.array(masterSV.getVelocity()) sxyz = np.array(slaveSV.getPosition()) aa = np.linalg.norm(sxyz-mxyz) costheta = (x[1]*x[1] + aa*aa - slvrng*slvrng)/(2.*x[1]*aa) Bpar.append(aa*costheta) perp = aa * np.sqrt(1 - costheta*costheta) direction = np.sign(np.dot( np.cross(targxyz-mxyz, sxyz-mxyz), mvel)) Bperp.append(direction*perp) catalog.addItem('parallel baseline at upperleft of master track', Bpar[0], 'runPreprocessor') catalog.addItem('parallel baseline at upperright of master track', Bpar[1], 'runPreprocessor') catalog.addItem('parallel baseline at lowerleft of master track', Bpar[2], 'runPreprocessor') catalog.addItem('parallel baseline at lowerright of master track', Bpar[3], 'runPreprocessor') catalog.addItem('parallel baseline at center of master track', Bpar[4], 'runPreprocessor') catalog.addItem('perpendicular baseline at upperleft of master track', Bperp[0], 'runPreprocessor') catalog.addItem('perpendicular baseline at upperright of master track', Bperp[1], 'runPreprocessor') catalog.addItem('perpendicular baseline at lowerleft of master track', Bperp[2], 'runPreprocessor') catalog.addItem('perpendicular baseline at lowerright of master track', Bperp[3], 'runPreprocessor') catalog.addItem('perpendicular baseline at center of master track', Bperp[4], 'runPreprocessor') ################################################## #4. compute bounding box ################################################## masterBbox = getBboxGeo(self.master.track) slaveBbox = getBboxGeo(self.slave.track) catalog.addItem('master bounding box', masterBbox, 'runPreprocessor') catalog.addItem('slave bounding box', slaveBbox, 'runPreprocessor') catalog.printToLog(logger, "runPreprocessor") self._insar.procDoc.addAllFromCatalog(catalog) def check_overlap(ldr_m, img_m, ldr_s, img_s): from isceobj.Constants import SPEED_OF_LIGHT rangeSamplingRateMaster, widthMaster, nearRangeMaster = read_param_for_checking_overlap(ldr_m, img_m) rangeSamplingRateSlave, widthSlave, nearRangeSlave = read_param_for_checking_overlap(ldr_s, img_s) farRangeMaster = nearRangeMaster + (widthMaster-1) * 0.5 * SPEED_OF_LIGHT / rangeSamplingRateMaster farRangeSlave = nearRangeSlave + (widthSlave-1) * 0.5 * SPEED_OF_LIGHT / rangeSamplingRateSlave #This should be good enough, although precise image offsets are not used. if farRangeMaster <= nearRangeSlave: overlapRatio = 0.0 elif farRangeSlave <= nearRangeMaster: overlapRatio = 0.0 else: # 0 1 2 3 ranges = np.array([nearRangeMaster, farRangeMaster, nearRangeSlave, farRangeSlave]) rangesIndex = np.argsort(ranges) overlapRatio = ranges[rangesIndex[2]]-ranges[rangesIndex[1]] / (farRangeMaster-nearRangeMaster) return overlapRatio def read_param_for_checking_overlap(leader_file, image_file): from isceobj.Sensor import xmlPrefix import isceobj.Sensor.CEOS as CEOS #read from leader file fsampConst = { 104: 1.047915957140240E+08, 52: 5.239579785701190E+07, 34: 3.493053190467460E+07, 17: 1.746526595233730E+07 } fp = open(leader_file,'rb') leaderFDR = CEOS.CEOSDB(xml=os.path.join(xmlPrefix,'alos2_slc/leader_file.xml'),dataFile=fp) leaderFDR.parse() fp.seek(leaderFDR.getEndOfRecordPosition()) sceneHeaderRecord = CEOS.CEOSDB(xml=os.path.join(xmlPrefix,'alos2_slc/scene_record.xml'),dataFile=fp) sceneHeaderRecord.parse() fp.seek(sceneHeaderRecord.getEndOfRecordPosition()) fsamplookup = int(sceneHeaderRecord.metadata['Range sampling rate in MHz']) rangeSamplingRate = fsampConst[fsamplookup] fp.close() #print('{}'.format(rangeSamplingRate)) #read from image file fp = open(image_file, 'rb') imageFDR = CEOS.CEOSDB(xml=os.path.join(xmlPrefix,'alos2_slc/image_file.xml'), dataFile=fp) imageFDR.parse() fp.seek(imageFDR.getEndOfRecordPosition()) imageData = CEOS.CEOSDB(xml=os.path.join(xmlPrefix,'alos2_slc/image_record.xml'), dataFile=fp) imageData.parseFast() width = imageFDR.metadata['Number of pixels per line per SAR channel'] near_range = imageData.metadata['Slant range to 1st data sample'] fp.close() #print('{}'.format(width)) #print('{}'.format(near_range)) return (rangeSamplingRate, width, near_range)