[Live-devel] Another question about audio PCMU

[Fu-Yuan Cheng]

Hello again,

I try to use openRTSP to grab MPEG4 frame from a IP-CAM 
and output as QuickTime MP4 format.
I use such command:
./openRTSP -4 -w 640 -h 480 -f 15 -e 30 rtsp://192.168.1.166/mpeg4 > skinner.mp4

And the messages after running is below:
Opened URL "rtsp://192.168.1.166/mpeg4"
Created receiver for "video/MP4V-ES" subsession (client ports 32782-32783)
Created receiver for "audio/PCMU" subsession (client ports 32784-32785)
Setup "video/MP4V-ES" subsession (client ports 32782-32783)
Setup "audio/PCMU" subsession (client ports 32784-32785)
width = 640, height = 480, fps = 15
width = 640, height = 480, fps = 15
Started playing session
Receiving streamed data (for up to 30.000000 seconds)...

I can use WMP on M$ to play this skinner.mp4 with 3ivx codec.
However, it just show video but no audio.
Yes, it has video show but soundless.

I am sure that openRTSP really recognize this audio format and grab it.
But why it is soundless if I play this mp4 file?
By the way, if I use realplayer or QuickTime on M$ 
and connect the rtsp stream from IP-CAM,
it really show both video and audio.

So, what is the problem?
Maybe anyone could give me some hints or other?
Thanks very much and big thank.

best regards,
skinner