[gst-devel] Problem of transporting the ts stream over WLAN802.11

[Zhiqiang Liu]

Hi ScreenName01,
 
Thanks for your help:-) 
 
The "ideal environment" refer to transport the udp packets in the wire communication. In this case, The possiblity of losing the packets is very small.

There seems to be no encryption problem since we can send the raw mpeg streams over the air to the target and play on it. 

It's really an unusual problem since we know that the the underlying medium is hidden to the protocol. The only possibly problem can occur in the MAC layer. The WLAN may lose some packets (About 10% packets are lost). But in the wire communication almost very packets are delivered normally. The problem may be related to the ts stream format. That's because it may be hard to play an ts stream when some packets are lost.

Thanks for your suggestion. I will try to analyse the traffic using wireshark.

I would like to keep in touch with you. When we get any progress, I will contact you.

 

Best regards,

Zhiqiang Liu

ScreenName01 wrote:
>Hi Zhiqiang,
>
>  I'm unclear of what the problem is.  What is an "ideal environment" for
>instance?
>
>  The underlying medium -- be it ethernet or wifi -- is transparent.  The
>medium is hidden to the protocol and is handled by the OS in most cases.
>
>  Make sure your router is routing the packets properly and in addition any
>firewalls allow the sending/receiving of udp packets between the host and
>the target.  A simple way to find out is just to hook up wireshark to see
>the wired traffic.  If you want to see the traffic over the air you will
>need airpcap and set your encryption to none to make it easier/possible to
>decode the packets.
>
>SN01
>
>
>Zhiqiang Liu wrote:
>> 
>> Hi all,
>> 
>> I tried to mux the h264 video and acc audio using the flutsmux element.
>> 
>> the following is my pipeline :
>> gst-launch -v flutsmux name=mux ! queue ! udpsink host=127.0.0.1 port=5002 
>> filesrc location=dvb2.ts ! flutsdemux name=demuxer demuxer. ! queue !
>> mpeg2dec ! ffmpegcolorspace ! videorate ! video/x-raw-yuv,framerate=15/1 !
>> videoscale ! video/x-raw-yuv,height=144,width=176 ! x264enc ! queue ! mux.
>> demuxer. ! queue ! flump3dec ! audioconvert ! audioresample ! faac ! queue
>> ! mux.
>> 
>> Then I used the mplayer to play the ts stream
>> mplayer udp://127.0.0.1:5002
>> 
>> It can play the ts stream normally in an ideal environment ( without
>> packet lossy)
>> But when I tried to send the stream over WLAN802.11 (With packet lossy),
>> the mplayer can not play the stream.
>> 
>> Are there somebody can give some solutions to the problem ?
>> Can the MPEG TS stream be transported over 802.11 ? 
>> 
>> Best regards,
>> Alex Liu
>> 
>> 
>> 
>> 
>> 
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