roipac.py
# This Python module is part of the PyRate software package.
#
# Copyright 2017 Geoscience Australia
#
# 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.
"""
This Python module contains tools for reading ROI_PAC format input data.
"""
#import os
import re
import datetime
import pyrate.ifgconstants as ifc
# ROIPAC RSC header file constants
WIDTH = "WIDTH"
FILE_LENGTH = "FILE_LENGTH"
XMIN = "XMIN"
XMAX = "XMAX"
YMIN = "YMIN"
YMAX = "YMAX"
X_FIRST = "X_FIRST"
X_STEP = "X_STEP"
X_UNIT = "X_UNIT"
Y_FIRST = "Y_FIRST"
Y_STEP = "Y_STEP"
Y_UNIT = "Y_UNIT"
TIME_SPAN_YEAR = "TIME_SPAN_YEAR"
# Old ROIPAC headers (may not be needed)
ORBIT_NUMBER = "ORBIT_NUMBER"
VELOCITY = "VELOCITY"
HEIGHT = "HEIGHT"
EARTH_RADIUS = "EARTH_RADIUS"
WAVELENGTH = "WAVELENGTH"
DATE = "DATE"
DATE12 = "DATE12"
HEADING_DEG = "HEADING_DEG"
# DEM specific
Z_OFFSET = "Z_OFFSET"
Z_SCALE = "Z_SCALE"
PROJECTION = "PROJECTION"
DATUM = "DATUM"
# custom header aliases
MASTER = "MASTER"
SLAVE = "SLAVE"
X_LAST = "X_LAST"
Y_LAST = "Y_LAST"
RADIANS = "RADIANS"
ROIPAC = "ROIPAC"
# store type for each of the header items
INT_HEADERS = [WIDTH, FILE_LENGTH, XMIN, XMAX, YMIN, YMAX, Z_OFFSET, Z_SCALE]
STR_HEADERS = [X_UNIT, Y_UNIT, ORBIT_NUMBER, DATUM, PROJECTION]
FLOAT_HEADERS = [X_FIRST, X_STEP, Y_FIRST, Y_STEP, TIME_SPAN_YEAR,
VELOCITY, HEIGHT, EARTH_RADIUS, WAVELENGTH, HEADING_DEG]
DATE_HEADERS = [DATE, DATE12]
ROIPAC_HEADER_LEFT_JUSTIFY = 18
ROI_PAC_HEADER_FILE_EXT = "rsc"
def parse_date(dstr):
"""
Parses ROI_PAC 'yymmdd' or 'yymmdd-yymmdd' format string to datetime.
:param str dstr: 'date' or 'date1-date2' string
:return: dstr: datetime string or tuple
:rtype: str or tuple
"""
def to_date(date_str):
"""convert string to datetime"""
year, month, day = [int(date_str[i:i+2]) for i in range(0, 6, 2)]
year += 1900 if ((year <= 99) and (year >= 50)) else 2000
return datetime.date(year, month, day)
if "-" in dstr: # ranged date
return tuple([to_date(d) for d in dstr.split("-")])
else:
return to_date(dstr)
def parse_header(hdr_file):
"""
Parses ROI_PAC header file metadata to a dictionary.
:param str hdr_file: `path to ROI_PAC *.rsc file`
:return: subset: subset of metadata
:rtype: dict
"""
with open(hdr_file) as f:
text = f.read()
try:
lines = [e.split() for e in text.split("\n") if e != ""]
headers = dict(lines)
is_dem = True if DATUM in headers or Z_SCALE in headers \
or PROJECTION in headers else False
if is_dem and DATUM not in headers:
msg = 'No "DATUM" parameter in DEM header/resource file'
raise RoipacException(msg)
except ValueError:
msg = "Unable to parse content of %s. Is it a ROIPAC header file?"
raise RoipacException(msg % hdr_file)
for k in headers.keys():
if k in INT_HEADERS:
headers[k] = int(headers[k])
elif k in STR_HEADERS:
headers[k] = str(headers[k])
elif k in FLOAT_HEADERS:
headers[k] = float(headers[k])
elif k in DATE_HEADERS:
headers[k] = parse_date(headers[k])
else: # pragma: no cover
pass # ignore other headers
# grab a subset for GeoTIFF conversion
subset = {ifc.PYRATE_NCOLS: headers[WIDTH],
ifc.PYRATE_NROWS: headers[FILE_LENGTH],
ifc.PYRATE_LAT: headers[Y_FIRST],
ifc.PYRATE_LONG: headers[X_FIRST],
ifc.PYRATE_X_STEP: headers[X_STEP],
ifc.PYRATE_Y_STEP: headers[Y_STEP]}
if is_dem:
subset[ifc.PYRATE_DATUM] = headers[DATUM]
else:
subset[ifc.PYRATE_WAVELENGTH_METRES] = headers[WAVELENGTH]
# grab master/slave dates from header, or the filename
has_dates = True if DATE in headers and DATE12 in headers else False
dates = headers[DATE12] if has_dates else _parse_dates_from(hdr_file)
subset[ifc.MASTER_DATE], subset[ifc.SLAVE_DATE] = dates
# replace time span as ROIPAC is ~4 hours different to (slave - master)
timespan = (subset[ifc.SLAVE_DATE] - subset[ifc.MASTER_DATE]).days / ifc.DAYS_PER_YEAR
subset[ifc.PYRATE_TIME_SPAN] = timespan
# Add data units of interferogram
subset[ifc.DATA_UNITS] = RADIANS
# Add InSAR processor flag
subset[ifc.PYRATE_INSAR_PROCESSOR] = ROIPAC
# add custom X|Y_LAST for convenience
subset[X_LAST] = headers[X_FIRST] + (headers[X_STEP] * (headers[WIDTH]))
subset[Y_LAST] = headers[Y_FIRST] + (headers[Y_STEP] * (headers[FILE_LENGTH]))
return subset
def _parse_dates_from(filename):
"""Determine dates from file name"""
# pylint: disable=invalid-name
# process dates from filename if rsc file doesn't have them (skip for DEMs)
p = re.compile(r'\d{6}-\d{6}') # match 2 sets of 6 digits separated by '-'
m = p.search(filename)
if m:
s = m.group()
min_date_len = 13 # assumes "nnnnnn-nnnnnn" format
if len(s) == min_date_len:
return parse_date(s)
else: # pragma: no cover
msg = "Filename does not include master/slave dates: %s"
raise RoipacException(msg % filename)
def manage_header(header_file, projection):
"""
Manage header files for ROI_PAC interferograms and DEM files.
NB: projection = roipac.parse_header(dem_file)[ifc.PYRATE_DATUM]
:param str header_file: `ROI_PAC *.rsc header file path`
:param projection: Projection obtained from dem header.
:return: combined_header: Combined metadata dictionary
:rtype: dict
"""
header = parse_header(header_file)
if ifc.PYRATE_DATUM not in header: # DEM already has DATUM
header[ifc.PYRATE_DATUM] = projection
header[ifc.DATA_TYPE] = ifc.ORIG # non-cropped, non-multilooked geotiff
return header
class RoipacException(Exception):
"""
Convenience class for throwing exception
"""
