import gobject
gobject.threads_init()
import pygst
pygst.require('0.10')
import gst
import sys
import time

last_time = None        # time of last inputted buffer
diff_sum = 0            # sum of time diff
nbbuffers = 0           # outputted buffers

ml = gobject.MainLoop()

def bus_cb(bus, message):
    if message.type in [gst.MESSAGE_ERROR, gst.MESSAGE_EOS]:
        ml.quit()

def inprobe(pad, buffer):
    global last_time
    last_time = time.time()
    return True

def outprobe(pad, buffer):
    now = time.time()
    global last_time, nbbuffers, diff_sum
    if last_time:
        diff_sum += now - last_time
        nbbuffers += 1
        last_time = 0
    return True

def padadded(demuxer, pad, decoder):
    if pad.get_caps().to_string().startswith("video"):
        pad.link(decoder.get_pad("sink"))

if len(sys.argv) < 4:
    print "Usage: %s <demuxername> <decodername> <filename>" % sys.argv[0]
    sys.exit()

p = gst.Pipeline()
src = gst.element_factory_make("filesrc")
src.props.location = sys.argv[3]
demuxer = gst.parse_launch(sys.argv[1])
decoder = gst.parse_launch(sys.argv[2])
sink = gst.element_factory_make("fakesink")

p.add(src, demuxer, decoder, sink)
src.link(demuxer)
decoder.link(sink)

demuxer.connect("pad-added", padadded, decoder)

decoder.get_pad("src").add_data_probe(inprobe)
decoder.get_pad("sink").add_data_probe(outprobe)

bus = p.get_bus()
bus.add_signal_watch()
bus.connect("message", bus_cb)

p.set_state(gst.STATE_PLAYING)

print "running"

ml.run()

print "Number of buffers:", nbbuffers
print "Average time : %0.10f seconds" % (diff_sum / nbbuffers)