add time_shift for delay stream

ffplayout.conf

@@ -63,6 +63,9 @@ ffmpeg_copy_settings = ["-c", "copy", "-bsf:v", "h264_mp4toannexb", "-threads",
 # filler_path are for the GUI only at the moment
 # filler_clip get handle different, when a new length needs to calculate
 # blackclip is for stream copy mode
+# time_shift adds or subtract seconds to the clip start,
+#   this is usefull for example for hls, because it have a big delay
+#   the value will be added to the clip begin
 [PLAYLIST]
 playlist_path = /playlists
 clips_root = /ADtvMedia
@@ -70,6 +73,7 @@ filler_path = /ADtvMedia/ADtv/03 - Musikalische Lückenfüller
 filler_clip = /ADtvMedia/ADtv/01 - Intro/seperator.clock.5-00.mp4
 blackclip = /opt/dummy20.mkv
 day_start = 6
+time_shift = -35
 
 
 # buffer settings

ffplayout.py

@@ -80,7 +80,8 @@ _playlist = SimpleNamespace(
     path=cfg.get('PLAYLIST', 'playlist_path'),
     start=cfg.getint('PLAYLIST', 'day_start'),
     filler=cfg.get('PLAYLIST', 'filler_clip'),
-    blackclip=cfg.get('PLAYLIST', 'blackclip')
+    blackclip=cfg.get('PLAYLIST', 'blackclip'),
+    shift=cfg.get('PLAYLIST', 'time_shift')
 )
 
 _buffer = SimpleNamespace(
@@ -509,7 +510,8 @@ def iter_src_commands():
             # loop through all clips in playlist
             for clip_node in clip_nodes:
                 src = clip_node.get('src')
-                begin = is_float(clip_node.get('begin'), last_time, True)
+                begin = is_float(
+                    clip_node.get('begin'), last_time, True) + _playlist.shift
                 duration = is_float(clip_node.get('dur'), dummy_len, True)
                 seek = is_float(clip_node.get('in'), 0, True)
                 out = is_float(clip_node.get('out'), dummy_len, True)