ISCE_INSAR/applications/focus.py

325 lines
13 KiB
Python

#!/usr/bin/env python3
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Copyright 2010 California Institute of Technology. ALL RIGHTS RESERVED.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
# United States Government Sponsorship acknowledged. This software is subject to
# U.S. export control laws and regulations and has been classified as 'EAR99 NLR'
# (No [Export] License Required except when exporting to an embargoed country,
# end user, or in support of a prohibited end use). By downloading this software,
# the user agrees to comply with all applicable U.S. export laws and regulations.
# The user has the responsibility to obtain export licenses, or other export
# authority as may be required before exporting this software to any 'EAR99'
# embargoed foreign country or citizen of those countries.
#
# Author: Walter Szeliga
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
import math
from isce import logging
import isceobj
from iscesys.Component.FactoryInit import FactoryInit
from iscesys.DateTimeUtil.DateTimeUtil import DateTimeUtil as DTU
class Focuser(object):
def __init__(self,rawObj=None):
self.rawObj = rawObj
self.logger = logging.getLogger('isce.focus')
def focuser(self):
"""
Create a make_raw object and then focus it!
"""
doppler = isceobj.Doppler.useDOPIQ()
hhRaw = self.make_raw(self.rawObj,doppler)
fd = hhRaw.getDopplerValues().getDopplerCoefficients(inHz=False)
# Hard-wire the doppler for point-target analysis
# C-band point target Doppler
fd = [0.0163810952106773,-0.0000382864254695,0.0000000012335234,0.0]
# L-band point target Doppler
#fd = [0.0700103587387314, 0.0000030023105646, -0.0000000000629754, 0.0]
self.focus(hhRaw,fd)
def make_raw(self,sensor,doppler):
"""
Extract the unfocused SAR image and associated data
@param sensor (\a isceobj.Sensor) the sensor object
@param doppler (\a isceobj.Doppler) the doppler object
@return (\a make_raw) a make_raw instance
"""
from make_raw import make_raw
import stdproc
import isceobj
# Extract raw image
self.logger.info("Creating Raw Image")
mr = make_raw()
mr.wireInputPort(name='sensor',object=sensor)
mr.wireInputPort(name='doppler',object=doppler)
mr.make_raw()
return mr
def focus(self,mr,fd):
"""
Focus SAR data
@param mr (\a make_raw) a make_raw instance
@param fd (\a float) Doppler centroid for focusing
"""
import stdproc
import isceobj
#from isceobj.Sensor.Generic import Generic
# Extract some useful variables
frame = mr.getFrame()
orbit = frame.getOrbit()
planet = frame.getInstrument().getPlatform().getPlanet()
# Calculate Peg Point
self.logger.info("Calculating Peg Point")
peg = self.calculatePegPoint(frame,orbit,planet)
V,H = self.calculateProcessingVelocity(frame,peg)
# Interpolate orbit
self.logger.info("Interpolating Orbit")
pt = stdproc.createPulsetiming()
pt.wireInputPort(name='frame',object=frame)
pt.pulsetiming()
orbit = pt.getOrbit()
# Convert orbit to SCH coordinates
self.logger.info("Converting orbit reference frame")
o2s = stdproc.createOrbit2sch()
o2s.wireInputPort(name='planet',object=planet)
o2s.wireInputPort(name='orbit',object=orbit)
o2s.wireInputPort(name='peg',object=peg)
o2s.setAverageHeight(H)
o2s.orbit2sch()
# Create Raw Image
rawImage = isceobj.createRawImage()
filename = frame.getImage().getFilename()
bytesPerLine = frame.getImage().getXmax()
goodBytes = bytesPerLine - frame.getImage().getXmin()
rawImage.setAccessMode('read')
rawImage.setByteOrder(frame.getImage().byteOrder)
rawImage.setFilename(filename)
rawImage.setNumberGoodBytes(goodBytes)
rawImage.setWidth(bytesPerLine)
rawImage.setXmin(frame.getImage().getXmin())
rawImage.setXmax(bytesPerLine)
rawImage.createImage()
# Create SLC Image
slcImage = isceobj.createSlcImage()
rangeSamplingRate = frame.getInstrument().getRangeSamplingRate()
rangePulseDuration = frame.getInstrument().getPulseLength()
chirpSize = int(rangeSamplingRate*rangePulseDuration)
chirpExtension = 0 #0.5*chirpSize
numberRangeBins = int(goodBytes/2) - chirpSize + chirpExtension
slcImage.setFilename(filename.replace('.raw','.slc'))
slcImage.setByteOrder(frame.getImage().byteOrder)
slcImage.setAccessMode('write')
slcImage.setDataType('CFLOAT')
slcImage.setWidth(numberRangeBins)
slcImage.createImage()
# Calculate motion compenstation correction for Doppler centroid
self.logger.info("Correcting Doppler centroid for motion compensation")
fdmocomp = stdproc.createFdMocomp()
fdmocomp.wireInputPort(name='frame',object=frame)
fdmocomp.wireInputPort(name='peg',object=peg)
fdmocomp.wireInputPort(name='orbit',object=o2s.getOrbit())
fdmocomp.setWidth(numberRangeBins)
fdmocomp.setSatelliteHeight(H)
fdmocomp.setDopplerCoefficients([fd[0],0.0,0.0,0.0])
fdmocomp.fdmocomp()
fd[0] = fdmocomp.getDopplerCentroid()
self.logger.info("Updated Doppler centroid: %s" % (fd))
# Calculate the motion compensation Doppler centroid correction plus rate
#self.logger.info("Testing new Doppler code")
#frate = stdproc.createFRate()
#frate.wireInputPort(name='frame',object=frame)
#frate.wireInputPort(name='peg', object=peg)
#frate.wireInputPort(name='orbit',object=o2s.getOrbit())
#frate.wireInputPort(name='planet',object=planet)
#frate.setWidth(numberRangeBins)
#frate.frate()
#fd = frate.getDopplerCentroid()
#fdrate = frate.getDopplerRate()
#self.logger.info("Updated Doppler centroid and rate: %s %s" % (fd,fdrate))
synthetic_aperature_length = self._calculateSyntheticAperatureLength(frame,V)
patchSize = self.nextpow2(2*synthetic_aperature_length)
valid_az_samples = patchSize - synthetic_aperature_length
rawFileSize = rawImage.getLength()*rawImage.getWidth()
linelength = rawImage.getXmax()
overhead = patchSize - valid_az_samples
numPatches = (1+int((rawFileSize/float(linelength)-overhead)/valid_az_samples))
# Focus image
self.logger.info("Focusing image")
focus = stdproc.createFormSLC()
focus.wireInputPort(name='rawImage',object=rawImage)
focus.wireInputPort(name='slcImage',object=slcImage)
focus.wireInputPort(name='orbit',object=o2s.getOrbit())
focus.wireInputPort(name='frame',object=frame)
focus.wireInputPort(name='peg',object=peg)
focus.wireInputPort(name='planet',object=planet)
focus.setDebugFlag(96)
focus.setBodyFixedVelocity(V)
focus.setSpacecraftHeight(H)
focus.setAzimuthPatchSize(patchSize)
focus.setNumberValidPulses(valid_az_samples)
focus.setSecondaryRangeMigrationFlag('n')
focus.setNumberAzimuthLooks(1)
focus.setNumberPatches(numPatches)
focus.setDopplerCentroidCoefficients(fd)
#focus.setDopplerCentroidCoefficients([fd[0], 0.0, 0.0])
focus.formslc()
mocompPos = focus.getMocompPosition()
fp = open('position.sch','w')
for i in range(len(mocompPos[0])):
fp.write("%f %f\n" % (mocompPos[0][i],mocompPos[1][i]))
fp.close()
slcImage.finalizeImage()
rawImage.finalizeImage()
# Recreate the SLC image
slcImage = isceobj.createSlcImage()
slcImage.setFilename(filename.replace('.raw','.slc'))
slcImage.setAccessMode('read')
slcImage.setDataType('CFLOAT')
slcImage.setWidth(numberRangeBins)
slcImage.createImage()
width = int(slcImage.getWidth())
length = int(slcImage.getLength())
# Create a frame object and write it out using the Generic driver
frame.setImage(slcImage)
frame.setOrbit(o2s.getOrbit())
#writer = Generic()
#writer.frame = frame
#writer.write('test.h5',compression='gzip')
slcImage.finalizeImage()
self.width = width
self.length = length
def calculateProcessingVelocity(self,frame,peg):
"""
Calculate the optimal processing velocity and height from the orbit.
@param frame (\a isceobj.Scene.Frame) the Frame object describing the unfocused SAR data
@param peg (\a isceobj.Location.Peg) a Peg point object defining the origin of the SCH coordinate system
@return (\a tuple) the processing velocity and satellite height
"""
from isceobj.Location.SCH import SCH
orbit = frame.getOrbit()
ellipsoid = frame.getInstrument().getPlatform().getPlanet().get_elp()
# Get the mid point of the orbit
midxyz = orbit.interpolateOrbit(frame.getSensingMid())
midllh = ellipsoid.xyz_to_llh(midxyz.getPosition())
# Calculate the SCH S-velocity
sch = SCH(peg=peg)
midsch = sch.xyz_to_sch(midxyz.getPosition())
midvsch = sch.vxyz_to_vsch(midsch,midxyz.getVelocity())
self.logger.debug("XYZ Velocity: %s" % (midxyz.getVelocity()))
self.logger.debug("SCH Velocity: %s" % (midvsch))
H = midllh[2] # The height at midswath
V = midvsch[0] # SCH S-velocity at midswath
self.logger.debug("Satellite Height: %s" % (H))
return V,H
def calculatePegPoint(self,frame,orbit,planet):
"""
Calculate the peg point used as the origin of the SCH coordinate system during focusing.
@param frame (\a isceobj.Scene.Frame) the Frame object describing the unfocused SAR data
@param orbit (\a isceobj.Orbit.Orbit) the orbit along which to calculate the peg point
@param planet (\a isceobj.Planet.Planet) the planet around which the satellite is orbiting
@return (\a isceobj.Location.Peg) the peg point
"""
from isceobj.Location.Peg import PegFactory
from isceobj.Location.Coordinate import Coordinate
# First, get the orbit nadir location at mid-swath and the end of the scene
midxyz = orbit.interpolateOrbit(frame.getSensingMid())
endxyz = orbit.interpolateOrbit(frame.getSensingStop())
# Next, calculate the satellite heading from the mid-point to the end of the scene
ellipsoid = planet.get_elp()
midllh = ellipsoid.xyz_to_llh(midxyz.getPosition())
endllh = ellipsoid.xyz_to_llh(endxyz.getPosition())
heading = math.degrees(ellipsoid.geo_hdg(midllh,endllh))
# Then create a peg point from this data
coord = Coordinate(latitude=midllh[0],longitude=midllh[1],height=0.0)
peg = PegFactory.fromEllipsoid(coordinate=coord,heading=heading,ellipsoid=ellipsoid)
self.logger.debug("Peg Point: %s" % (peg))
return peg
def _calculateSyntheticAperatureLength(self,frame,v):
"""
Calculate the length of the synthetic aperature in pixels.
@param frame (\a isceobj.Scene.Frame) the Frame object describing the unfocussed SAR data
"""
wavelength = frame.getInstrument().getRadarWavelength()
prf = frame.getInstrument().getPulseRepetitionFrequency()
L = frame.getInstrument().getPlatform().getAntennaLength()
farRange = frame.getFarRange()
syntheticAperatureLength = int(round((wavelength*farRange*prf)/(L*v),0))
return syntheticAperatureLength
def nextpow2(self,v):
v = v-1
v |= v >> 1;
v |= v >> 2;
v |= v >> 4;
v |= v >> 8;
v |= v >> 16;
v = v+1
return v
def main():
import sys
import isceobj
fi = FactoryInit()
fi.fileInit = sys.argv[1]
fi.defaultInitModule = 'InitFromXmlFile'
fi.initComponentFromFile()
reference = fi.getComponent('Reference')
focuser = Focuser(rawObj=reference)
focuser.focuser()
if __name__ == "__main__":
main()