Better support for RTK info

opendm/config.py

@@ -707,6 +707,17 @@ def config(argv=None):
                     help=('Use images\' GPS exif data for reconstruction, even if there are GCPs present.'
                           'This flag is useful if you have high precision GPS measurements. '
                           'If there are no GCPs, this flag does nothing. Default: %(default)s'))
+    
+    parser.add_argument('--gps-accuracy',
+                        type=float,
+                        action=StoreValue,
+                        metavar='<positive float>',
+                        default=15,
+                        help='Set a value in meters for the GPS Dilution of Precision (DOP) '
+                        'information for all images. If your images are tagged '
+                        'with high precision GPS information (RTK), this value will be automatically '
+                        'set accordingly. You can use this option to manually set it in case the reconstruction '
+                        'fails. Lowering this option can sometimes help control bowling-effects over large areas. Default: %(default)s')
 
     parser.add_argument('--optimize-disk-space',
                 action=StoreTrue,

opendm/osfm.py

@@ -103,6 +103,35 @@ class OSFMContext:
                 log.ODM_INFO("Multi-camera setup, using BOW matching")
                 use_bow = True
 
+            # GPSDOP override if we have GPS accuracy information (such as RTK)
+            override_gps_dop = 'gps_accuracy_is_set' in args
+            for p in photos:
+                if p.get_gps_dop() is not None:
+                    override_gps_dop = True
+                    break
+            
+            if override_gps_dop:
+                if 'gps_accuracy_is_set' in args:
+                    log.ODM_INFO("Forcing GPS DOP to %s for all images" % args.gps_accuracy)
+                else:
+                    log.ODM_INFO("Looks like we have RTK accuracy info for some photos. Good! We'll use it.")
+
+                exif_overrides = {}
+                for p in photos:
+                    dop = args.gps_accuracy if 'gps_accuracy_is_set' in args else p.get_gps_dop()
+                    if dop is not None and p.latitude is not None and p.longitude is not None:
+                        exif_overrides[p.filename] = {
+                            'gps': {
+                                'latitude': p.latitude,
+                                'longitude': p.longitude,
+                                'altitude': p.altitude if p.altitude is not None else 0,
+                                'dop': dop,
+                            }
+                        }
+
+                with open(os.path.join(self.opensfm_project_path, "exif_overrides.json"), 'w') as f:
+                    f.write(json.dumps(exif_overrides))
+
             # create config file for OpenSfM
             config = [
                 "use_exif_size: no",

opendm/photo.py

@@ -60,6 +60,10 @@ class ODM_Photo:
         # self.center_wavelength = None
         # self.bandwidth = None
 
+        # RTK
+        self.gps_xy_stddev = None # Dilution of Precision X/Y
+        self.gps_z_stddev = None # Dilution of Precision Z
+
         # parse values from metadata
         self.parse_exif_values(path_file)
 
@@ -183,6 +187,22 @@ class ODM_Photo:
                         'Camera:Irradiance',                    
                     ], float)
 
+                    # Phantom 4 RTK
+                    if '@drone-dji:RtkStdLon' in tags:
+                        y = float(self.get_xmp_tag(tags, '@drone-dji:RtkStdLon'))
+                        x = float(self.get_xmp_tag(tags, '@drone-dji:RtkStdLat'))
+                        self.gps_xy_stddev = max(x, y)
+                    
+                        if '@drone-dji:RtkStdHgt' in tags:
+                            self.gps_z_stddev = float(self.get_xmp_tag(tags, '@drone-dji:RtkStdHgt'))
+                    else:
+                        self.set_attr_from_xmp_tag('gps_xy_stddev', tags, [
+                            '@Camera:GPSXYAccuracy'
+                        ], float)
+                        self.set_attr_from_xmp_tag('gps_z_stddev', tags, [
+                            '@Camera:GPSZAccuracy'
+                        ], float)
+
                     if 'DLS:Yaw' in tags:
                         self.set_attr_from_xmp_tag('dls_yaw', tags, ['DLS:Yaw'], float)
                         self.set_attr_from_xmp_tag('dls_pitch', tags, ['DLS:Pitch'], float)
@@ -239,6 +259,7 @@ class ODM_Photo:
 
         if xmp_start < xmp_end:
             xmp_str = img_str[xmp_start:xmp_end + 12]
+            xmp_str = xmp_str.replace("rdf:about=''xmlns", "rdf:about='' xmlns")
             xdict = x2d.parse(xmp_str)
             xdict = xdict.get('x:xmpmeta', {})
             xdict = xdict.get('rdf:RDF', {})
@@ -361,4 +382,15 @@ class ODM_Photo:
         if self.bits_per_sample:
             return float(2 ** self.bits_per_sample)
 
+        return None
+
+    def get_gps_dop(self):
+        val = -9999
+        if self.gps_xy_stddev is not None:
+            val = self.gps_xy_stddev
+        if self.gps_z_stddev is not None:
+            val = max(val, self.gps_z_stddev)
+        if val > 0:
+            return val
+
         return None