adding orbit direction attribute (#30)

* adding orbit direction attribute
* apply rename

Author: LiangJYu

src/s1reader/s1_burst_slc.py

@@ -35,7 +35,7 @@ def compute_az_carrier(burst, orbit, offset, position):
     fmt = "%Y-%m-%dT%H:%M:%S.%f"
     orbit_ref_epoch = datetime.datetime.strptime(orbit.reference_epoch.__str__()[:-3], fmt)
 
-    t_mid = burst.get_sensing_mid() - orbit_ref_epoch
+    t_mid = burst.sensing_mid - orbit_ref_epoch
     _, v = orbit.interpolate(t_mid.total_seconds())
     vs = np.linalg.norm(v)
     ks = 2 * vs * burst.azimuth_steer_rate / burst.wavelength
@@ -184,6 +184,7 @@ class Sentinel1BurstSlc:
     center: tuple # {center lon, center lat} in degrees
     border: list # list of lon, lat coordinate tuples (in degrees) representing burst border
     orbit: isce3.core.Orbit
+    orbit_direction: str
     # VRT params
     tiff_path: str  # path to measurement tiff in SAFE/zip
     i_burst: int

src/s1reader/s1_reader.py

@@ -287,6 +287,7 @@ def burst_from_xml(annotation_path: str, orbit_path: str, tiff_path: str,
         azimuth_steer_rate = np.radians(float(product_info_element.find('azimuthSteeringRate').text))
         radar_freq = float(product_info_element.find('radarFrequency').text)
         range_sampling_rate = float(product_info_element.find('rangeSamplingRate').text)
+        orbit_direction = product_info_element.find('pass').text
 
         image_info_element = tree.find('imageAnnotation/imageInformation')
         azimuth_time_interval = float(image_info_element.find('azimuthTimeInterval').text)
@@ -379,8 +380,9 @@ def burst_from_xml(annotation_path: str, orbit_path: str, tiff_path: str,
                                       range_sampling_rate, range_pxl_spacing,
                                       (n_lines, n_samples), az_fm_rate, doppler,
                                       rng_processing_bandwidth, pol, burst_id,
-                                      platform_id, center_pts[i], boundary_pts[i],
-                                      orbit, tiff_path, i, first_valid_sample,
+                                      platform_id, center_pts[i],
+                                      boundary_pts[i], orbit, orbit_direction,
+                                      tiff_path, i, first_valid_sample,
                                       last_sample, first_valid_line, last_line,
                                       range_window_type, range_window_coeff)