A very strange problem Video - gets delayed while streaming.

[digish_gabhawala]

Hello,

I am stuck to a strange problem since long.

Actually I am writing a video streamer application on mobile. I am recording mpeg4 data using profile level 4.
I am sending this stream to Darwin Streaming Server located in LAN and I am using RTSP for signaling and RTP for data transfer.

DSS(Darwin Streaming Server) is relaying the stream.

Now using VLC client, I am trying to play that stream. VLC successfully starts playing the stream but it is delaying the stream very much.

This is not the one time delay caused by relay.

When I am recording the video, and for e.g. there is 20 sec delay due to relay, then

my starting picture comes at vlc at 20th seconds. This is fine for me but then my source's 10th seconds' picture should come on VLC at 30th second. This is not happpening. video at VLC looks like slow - motion and it shows video of 10th second at 60-70th seconds.

If I record video for 1 minite, It will be played on VLC for 5-6 minites.

I have tried what all I can but I am not able to get it.

Please help! ! !


Following is the sdp that I used:

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v=0 o=- 1277851954 1277851954 IN IP4 127.0.0.0 s=Wirecast c=IN IP4 0.0.0.0 t=0 0 a=range:npt=now- a=control:* m=video 0 RTP/AVP 96 a=rtpmap:96 MP4V-ES/90000 a=fmtp:96 profile-level-id=1;config=000001B004000001B50ECF000001000000012000C488803250B04241463F a=cliprect:0,0,288,352 a=framesize:96 352-288 a=control:trackID=1

I have also verified that packet from my sender reaches to DSS on time and packets from DSS to VLC also reaches on time. But VLC bufferes the packets and then it plays video slowly.

I also tried to play the video streamed from wirecast but in that case it was played fine with VLC. so there is no doubt that VLC or DSS is doing something wrong.

Can anyone tell me how to verify that why my packets are being played slowly?

Here are some video packets's starting data bytes which I have captured using wireshark...

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000001b653780c86 000001b655181086 000001b655fc1486 000001b656b81886 000001b658781886

Thanks in advance,
-Digish

[digish_gabhawala]

Hello,

Here is the information of the case that is working via virecast.

SDP:

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v=0 o=- 927002389 927002389 IN IP4 127.0.0.0 s=Wirecast c=IN IP4 0.0.0.0 t=0 0 a=range:npt=now- a=control:* m=video 0 RTP/AVP 96 a=rtpmap:96 MP4V-ES/90000 a=fmtp:96 profile-level-id=1;config=000001B0F3000001B50EE040C0CF0000010000000120008440FA28582120A31F a=cliprect:0,0,288,352 a=framesize:96 352-288 a=control:trackID=1

Few packet's Starting data:

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000001b650038098 000001b65003009B 000001b650038098 000001b650030098 000001b65003809b 000001b65003009b

As per mp4v,
Those initial bits should contain, vop coding type, modulo time base, vop time increment.

But in this success case, it seems to me tht its always 0. How can this be?

Is my understanding wrong?
Plzz help!
-Digish

[digish_gabhawala]

Can anyone please help?

Thanks,
Digish