Update cue2vtt.py

examples/stream/cue2vtt.py

@@ -10,14 +10,22 @@
 """
 
 import sys
-from threefive import Stream
 import time
+from iframes import IFramer
+from threefive import Stream
+
+
+def first():
+    global start_pts
+    iframer = IFramer(shush=True)
+    start_pts = iframer.first(sys.argv[1])
 
 
 def ts_to_vtt(timestamp):
     """
     ts_to_vtt converts timestamp into webvtt times
     """
+    timestamp -= start_pts
     hours, seconds = divmod(timestamp, 3600)
     mins, seconds = divmod(seconds, 60)
     seconds = round(seconds, 3)
@@ -28,17 +36,19 @@ def scte35_to_vtt(cue):
     """
     scte35_to_vtt prints splice insert cue out and cue in via webvtt
     """
-    start = 0
-    end = 0
+    cue_start = 0
+    cue_end = 0
     duration = None
     pts_time = None
     upid = None
     seg_mesg = None
     now = cue.packet_data.pts
     if cue.command.has("pts_time"):
-        start = pts_time = cue.command.pts_time + cue.info_section.pts_adjustment
-        if pts_time > now:
-            time.sleep(pts_time - now)
+        cue_start = cue.command.pts_time + cue.info_section.pts_adjustment
+    else:
+        cue_start = now
+    if cue_start > now:
+        time.sleep(cue_start - now)
     if cue.command.has("break_duration"):
         duration = cue.command.break_duration
     for d in cue.descriptors:
@@ -48,16 +58,20 @@ def scte35_to_vtt(cue):
                 upid = d.segmentation_upid
             if d.has("segmentation_message"):
                 seg_mesg = d.segmentation_message
-    if start and duration:
-        end = start + duration
-    if end == 0:
-        end = start + 4
+    if cue_start:
+        cue_end = cue_start + 2
+    ##    if cue_end == 0:
+    ##        end = start + 4
 
-    print(f"{ts_to_vtt(start)} --> {ts_to_vtt(end)} ")
+    print(f"{ts_to_vtt(cue_start)} --> {ts_to_vtt(cue_end)} ")
 
     print(f"Cmd: {cue.command.name}    ")
-    if pts_time:
-        print(f"PTS:  {pts_time}  ")
+    pts_time = None
+    if cue.command.pts_time:
+        pts_time = cue.command.pts_time + cue.info_section.pts_adjustment
+    else:
+        pts_time = now
+    print(f"PTS:  {pts_time}  ")
     if duration:
         print(f"Duration:  {round(duration,3)} ")
     if seg_mesg:
@@ -69,6 +83,7 @@ def scte35_to_vtt(cue):
 
 if __name__ == "__main__":
     arg = sys.argv[1]
+    first()
     print("WEBVTT\n\n\n")
     strm = Stream(arg)
     strm.decode(func=scte35_to_vtt)