Added script to update timestamps.

scripts/update-subs.py

@@ -0,0 +1,50 @@
+
+import re
+import sys
+import argparse
+
+def offset_timestamp(timestamp, offset):
+    hours, minutes, seconds, microseconds = map(float, re.split('[:.]', timestamp))
+    total_seconds = hours * 3600 \
+        + minutes * 60 \
+        + seconds  \
+        + (microseconds * 0.001) \
+        + offset
+    new_hours = int(total_seconds // 3600)
+    new_minutes = int((total_seconds % 3600) // 60)
+    new_seconds = total_seconds % 60
+    return f"{new_hours:02}:{new_minutes:02}:{new_seconds:.3f}"
+
+def update_webvtt(file_path, offset):
+    with open(file_path, 'r', encoding='utf-8') as file:
+        lines = file.readlines()
+
+    updated_lines = []
+    for line in lines:
+        ts = line[:line.find("align")]
+        if '-->' in ts:
+            start, end = ts.split(' --> ')
+            updated_start = offset_timestamp(start.strip(), offset)
+            updated_end = offset_timestamp(end.strip(), offset)
+            updated_lines.append(f"{updated_start} --> {updated_end}\n")
+        else:
+            updated_lines.append(line)
+
+    with open('updated_' + file_path, 'w', encoding='utf-8') as file:
+        file.writelines(updated_lines)
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser()
+    parser.add_argument('input_file', type=str, help='The input file name')
+    parser.add_argument('time_offset', type=str, help='The output file name')
+    args = parser.parse_args()
+
+    vtt = args.input_file
+    t   = args.time_offset
+    
+    minutes, seconds = map(float, re.split('[:.]', t))
+    offset = minutes * 60 + seconds
+
+    print("bumping timestamps in file %s by %f seconds" % (vtt,  offset))
+    update_webvtt(vtt, -offset)  # Use -40 to offset back by 40 seconds
+