WARNING: erroneous pipeline: could not link rtpl16pay0 to udpsink0

[Tim Müller]

On Tue, 2017-09-19 at 23:03 -0700, amsts wrote:

Hi,

> I want to play a wave file as following 
> 
>  gst-launch-1.0 -v filesrc location=./mysong.wav ! wavparse !
> audioconvert !
> rtpL16pay ! application/x-rtp, payload=11, encoding-name=L16,
> clock-rate=16000, channels=1 ! udpsink host=localhost port=6000
> 
> I am getting a warning :
> 
> WARNING: erroneous pipeline: could not link rtpl16pay0 to udpsink0

Look at the source pad template caps in gst-inspect-1.0 rtpL16pay.

If you use payload type 10 or 11 that means you must use a sample rate
of 44100, which will result in clock-rate=44100 on the rtp output caps.

Your problem is that you specify both payload=11 and a non-44100 clock-
rate.

https://www.iana.org/assignments/rtp-parameters/rtp-parameters.xhtml#rt
p-parameters-1

One solution is to use an audioresample before rtpL16pay as well to
convert the input sample rate to 44100.

(It seems the only solution unless you wanat to use/re-encode to a
different format, since the restriction/requirement for non-dynamic pt
is on the VLC side according to the error message you post, if I
understood it correctly).

Cheers
 -Tim

-- 
Tim Müller, Centricular Ltd - http://www.centricular.com

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