grab sample_rate and center_freq from filename if missing

apps/iridium-extractor

@@ -3,6 +3,7 @@
 import time
 import getopt
 import sys
+import re
 import threading
 import os.path
 import argparse
@@ -291,6 +292,13 @@ if __name__ == "__main__":
         else:
             args.file_info = ''
 
+    # grab things from filename as fallback
+    if sample_rate is None and (g := re.search(r"-s(\d+(\.\d+)?(e[+-]\d+)?)-", filename)):
+        sample_rate = int(float(g.group(1)))
+
+    if center is None and (g := re.search(r"-f(\d+(\.\d+)?(e[+-]\d+)?)-", filename)):
+        center = int(float(g.group(1)))
+
     if sample_rate == None:
         print("Sample rate missing!", file=sys.stderr)
         exit(1)