Questions about buffer's timestamp in RTP application

[cee1]

Hi, all

I'm doing some experiment with gstreamer 0.10 in RTP application:
* Sender:
gst-launch-0.10 filesrc location=sample.ogg ! decodebin2 ! \
                x264enc tune=zerolatency byte-stream=true bitrate=1024
vbv-buf-capacity=300 \
                bframes=0 b-pyramid=true weightb=true me=dia key-int-max=48 ! \
                rtph264pay ! udpsink

* Receiver:
gst-launch-0.10 udpsrc
caps="application/x-rtp,media=(string)video,clock-rate=(int)90000" !
rtph264depay ! ffdec_h264 ! autovideosink

Went through the source, I found rtph264depay doesn't use RTP
timestamp and -- It seems the gstbuffer's timestamp is packet's
received time, so
1. What  does RTP timestamp do ?
2. How does the receiver play properly? I mean without new segment
event and gstbuffer's timestamp, how can the receiver play it at a
proper rate(e.g. 24FPS) ?



-- 
Regards,

- cee1