def get_los_geometry(self, geom_obj, print_msg=False):
"""Get the Line-of-Sight geometry info in incidence and azimuth angle in degrees."""
lat, lon = self.get_stat_lat_lon(print_msg=print_msg)
# get LOS geometry
if isinstance(geom_obj, str):
# geometry file
atr = readfile.read_attribute(geom_obj)
coord = coordinate(atr, lookup_file=geom_obj)
y, x = coord.geo2radar(lat, lon, print_msg=print_msg)[0:2]
# check against image boundary
y = max(0, y); y = min(int(atr['LENGTH'])-1, y)
x = max(0, x); x = min(int(atr['WIDTH'])-1, x)
box = (x, y, x+1, y+1)
inc_angle = readfile.read(geom_obj, datasetName='incidenceAngle', box=box, print_msg=print_msg)[0][0,0]
az_angle = readfile.read(geom_obj, datasetName='azimuthAngle', box=box, print_msg=print_msg)[0][0,0]
elif isinstance(geom_obj, dict):
# use mean inc/az_angle from metadata
inc_angle = ut.incidence_angle(geom_obj, dimension=0, print_msg=print_msg)
az_angle = ut.heading2azimuth_angle(float(geom_obj['HEADING']))
else:
raise ValueError('input geom_obj is neight str nor dict: {}'.format(geom_obj))
return inc_angle, az_angle
def get_full_resolution(meta_file):
"""
Grab the full resolution in terms of pixel_size and ground spacing
"""
# check metadata file extension: only ISCE format is supported.
fext = os.path.splitext(meta_file)[1]
if fext not in ['.xml', '.dat']:
raise ValueError('input ISCE metadata file extension "{}" not in [.xml, .dat]'.format(fext))
# get middle sub-swath xml file for Sentinel-1 data
if meta_file.endswith('.xml'):
meta_files = glob.glob(meta_file)
mid_idx = int(len(meta_files) / 2)
meta_file = meta_files[mid_idx]
# extract metadata
meta, frame = extract_isce_metadata(meta_file, update_mode=False)
meta['WIDTH'] = frame.numberOfSamples
# calculate the full azimuth/range ground resolution
az_pixel_size = float(meta['AZIMUTH_PIXEL_SIZE']) #azimuth pixel size on the orbit
rg_pixel_size = float(meta['RANGE_PIXEL_SIZE']) #range pixel size in LOS direction
height = float(meta['HEIGHT'])
inc_angle = ut.incidence_angle(meta, dimension=0)
az_spacing = az_pixel_size * EARTH_RADIUS / (EARTH_RADIUS + height) #azimuth pixel size on the ground
rg_spacing = rg_pixel_size / np.sin(inc_angle / 180. * np.pi) #range pixel size on the ground
return az_pixel_size, az_spacing, rg_pixel_size, rg_spacing
def get_los_geometry(self, geom_obj, print_msg=False):
lat, lon = self.get_stat_lat_lon(print_msg=print_msg)
# get LOS geometry
if isinstance(geom_obj, str):
# geometry file
atr = readfile.read_attribute(geom_obj)
coord = coordinate(atr, lookup_file=geom_obj)
y, x = coord.geo2radar(lat, lon, print_msg=print_msg)[0:2]
box = (x, y, x + 1, y + 1)
inc_angle = readfile.read(geom_obj,
datasetName='incidenceAngle',
box=box,
print_msg=print_msg)[0][0, 0]
az_angle = readfile.read(geom_obj,
datasetName='azimuthAngle',
box=box,
print_msg=print_msg)[0][0, 0]
head_angle = ut.azimuth2heading_angle(az_angle)
elif isinstance(geom_obj, dict):
# use mean inc/head_angle from metadata
inc_angle = ut.incidence_angle(geom_obj,
dimension=0,
print_msg=print_msg)
head_angle = float(geom_obj['HEADING'])
# for old reading of los.rdr band2 data into headingAngle directly
if (head_angle + 180.) > 45.:
head_angle = ut.azimuth2heading_angle(head_angle)
else:
raise ValueError(
'input geom_obj is neight str nor dict: {}'.format(geom_obj))
return inc_angle, head_angle
