CLAUDE: fopen_turn_finder.py — add lat/lon from *-ims.corr-xml

*-ims.corr-xml in the scene root dir always has an INS-fused GPS fix
(did_ins_2-lla, fallback did_gps1_pos-lla) giving the representative
position of the sequence for map location.

Changes:
- find_xml_files: also yields ims_path (*-ims.corr-xml from scene root)
- parse_lla(): reads lat/lon from INS or GPS1 LLA entry
- lat/lon added to metrics, console tables, and TSV output
Co-authored-by: Claude <claude@elphel.com>

scripts/fopen_turn_finder.py

@@ -197,12 +197,13 @@ def sequence_metrics(pose_arr, dt_arr):
 
 def find_xml_files(root):
     """
-    Yield (scene_ts_str, xml_path, hist_path_or_None) for every scene dir
-    under root.  Picks the latest version subdirectory by name (e.g. v88 > v80).
+    Yield (scene_ts_str, xml_path, hist_path_or_None, ims_path_or_None)
+    for every scene dir under root.
+    Picks the latest version subdirectory by name (e.g. v88 > v80).
     Skips directories whose name ends with '-index'.
 
-    hist_path is the *-elevations_histogram.csv inside the version subdir,
-    or None if not present.
+    hist_path  — *-elevations_histogram.csv inside the version subdir (AGL)
+    ims_path   — *-ims.corr-xml in the scene root dir (GPS lat/lon/alt)
     """
     try:
         scene_dirs = sorted(os.listdir(root))
@@ -231,8 +232,11 @@ def find_xml_files(root):
         ver_path  = os.path.join(scene_path, ver)
         xml_path  = os.path.join(ver_path,   f"{scene}-INTERFRAME.corr-xml")
         hist_path = os.path.join(ver_path,   f"{scene}-elevations_histogram.csv")
+        ims_path  = os.path.join(scene_path, f"{scene}-ims.corr-xml")
         if os.path.isfile(xml_path):
-            yield scene, xml_path, (hist_path if os.path.isfile(hist_path) else None)
+            yield (scene, xml_path,
+                   hist_path if os.path.isfile(hist_path) else None,
+                   ims_path  if os.path.isfile(ims_path)  else None)
 
 
 def parse_agl(hist_path):
@@ -256,6 +260,41 @@ def parse_agl(hist_path):
         return float('nan')
 
 
+def parse_lla(ims_path):
+    """
+    Read latitude, longitude, altitude from *-ims.corr-xml.
+
+    The file lives in the scene root directory (not the version subdir)
+    and always contains a single representative GPS fix for the sequence.
+
+    Key priority (most to least accurate):
+      did_ins_2-lla   — INS fused GPS+IMU position  (preferred)
+      did_gps1_pos-lla — raw GPS1 position           (fallback)
+
+    Format of each entry value: "lat, lon, alt_m"
+
+    Returns (lat, lon) as floats, or (nan, nan) on failure.
+    """
+    nan = float('nan')
+    try:
+        tree    = ET.parse(ims_path)
+        entries = {e.get("key"): e.text
+                   for e in tree.getroot().findall("entry")}
+    except Exception:
+        return nan, nan
+
+    for key in ("did_ins_2-lla", "did_gps1_pos-lla"):
+        val = entries.get(key, "")
+        if val:
+            try:
+                parts = [float(v) for v in val.split(",")]
+                if len(parts) >= 2:
+                    return parts[0], parts[1]
+            except ValueError:
+                continue
+    return nan, nan
+
+
 # ─────────────────────────────── main ────────────────────────────────────── #
 
 def main():
@@ -280,7 +319,7 @@ def main():
 
     print(f"Scanning {args.root} …", flush=True)
     rows = []
-    for scene_ts, xml_path, hist_path in find_xml_files(args.root):
+    for scene_ts, xml_path, hist_path, ims_path in find_xml_files(args.root):
         pose_arr, dt_arr = parse_xml(xml_path)
         if pose_arr is None:
             continue
@@ -288,6 +327,9 @@ def main():
         m['scene_ts'] = scene_ts
         m['xml_path'] = xml_path
         m['agl_m']    = parse_agl(hist_path) if hist_path else float('nan')
+        lat, lon      = parse_lla(ims_path)  if ims_path  else (float('nan'), float('nan'))
+        m['lat']      = lat
+        m['lon']      = lon
         rows.append(m)
 
     print(f"Parsed {len(rows)} sequences.", flush=True)
@@ -321,8 +363,8 @@ def main():
     display.sort(key=lambda r: r.get(sort_key) or 0, reverse=True)
 
     # ── console report ────────────────────────────────────────────────────
-    hdr = (f"  {'Scene':>22}  {'fr':>4}  {'AGL(m)':>7}  {'range(°)':>8}  "
-           f"{'dt_max(°/s)':>11}  {'at timestamp':>20}  "
+    hdr = (f"  {'Scene':>22}  {'fr':>4}  {'AGL(m)':>7}  {'lat':>11}  {'lon':>12}  "
+           f"{'range(°)':>8}  {'dt_max(°/s)':>11}  {'at timestamp':>20}  "
            f"{'glitch':>7}  {'fd_max(°/s)':>11}")
 
     for axis, label in (('r', 'R (heading/course)'),
@@ -338,8 +380,13 @@ def main():
         print(hdr)
         for r in ranked[:args.top]:
             agl  = r.get('agl_m', float('nan'))
+            lat  = r.get('lat',   float('nan'))
+            lon  = r.get('lon',   float('nan'))
             agl_s = f"{agl:7.1f}" if np.isfinite(agl) else "    n/a"
+            lat_s = f"{lat:11.6f}" if np.isfinite(lat) else "        n/a"
+            lon_s = f"{lon:12.6f}" if np.isfinite(lon) else "         n/a"
             print(f"  {r['scene_ts']:>22}  {r['n_frames']:>4}  {agl_s}  "
+                  f"{lat_s}  {lon_s}  "
                   f"{r[f'{axis}_range(deg)']:>8.2f}  "
                   f"{r[f'{axis}_dt_max(deg/s)']:>11.3f}  "
                   f"{r[f'{axis}_dt_ts']:>20.3f}  "
@@ -349,7 +396,7 @@ def main():
     # ── TSV output ────────────────────────────────────────────────────────
     if args.out:
         fieldnames = [
-            'scene_ts', 'n_frames', 'duration_s', 'agl_m',
+            'scene_ts', 'n_frames', 'duration_s', 'agl_m', 'lat', 'lon',
             'r_dt_max(deg/s)', 'r_dt_ts', 'r_range(deg)', 'r_glitch', 'r_fd_max(deg/s)',
             't_dt_max(deg/s)', 't_dt_ts', 't_range(deg)', 't_glitch', 't_fd_max(deg/s)',
             'a_dt_max(deg/s)', 'a_dt_ts', 'a_range(deg)', 'a_glitch', 'a_fd_max(deg/s)',