Cum sa folosesti segment-ul pentru cautare in GStreamer

# Abordare incorecta - recrearea pipeline-ului la fiecare cautare
def seek_wrong(pipeline, position):
    pipeline.set_state(Gst.State.NULL)
    # Se pierde tot contextul si bufferele
    pipeline.set_state(Gst.State.PLAYING)

# Cautare fara segment
gst-launch-1.0 filesrc location=video.mp4 ! qtdemux ! h264parse ! avdec_h264 ! videoconvert ! autovideosink
# Nu exista mecanism de cautare

import gi
gi.require_version('Gst', '1.0')
from gi.repository import Gst, GLib

Gst.init(None)
loop = GLib.MainLoop()

pipeline = Gst.parse_launch("filesrc location=video.mp4 ! qtdemux ! h264parse ! avdec_h264 ! videoconvert ! autovideosink")

# Cautare la pozitia 30 de secunde (in nanosecunde)
def seek_to(pipeline, seconds):
    event = Gst.Event.new_seek(
        1.0,                      # rata
        Gst.Format.TIME,
        Gst.SeekFlags.FLUSH | Gst.SeekFlags.ACCURATE,
        Gst.SeekType.SET,        # tipul de cautare: SET = absolut
        seconds * Gst.SECOND,
        Gst.SeekType.NONE,       # pozitia de stop
        -1
    )
    pipeline.send_event(event)

# Programeaza cautarea dupa 2 secunde de redare
GLib.timeout_add_seconds(2, seek_to, pipeline, 30)

bus = pipeline.get_bus()
bus.add_signal_watch()

def on_message(bus, message):
    if message.type == Gst.MessageType.ERROR:
        err, debug = message.parse_error()
        print(f"Eroare: {err}")
        loop.quit()
    elif message.type == Gst.MessageType.EOS:
        print("Redare incheiata")
        loop.quit()
    return True

bus.connect("message", on_message)
pipeline.set_state(Gst.State.PLAYING)
loop.run()