streaming soundcard in wav/raw/pcm

[majidaldo]

I want to stream my sound card output over my lan using minimum cpu and latency. so, ideally, no transcoding (except for raw->wav "transcoding")

i tried dozens of configurations but wasn't successful.
I need to know what:
- network protocol
- encapsulation
- transcoding (if any)
to use

[Rémi Denis-Courmont]

With VLC 1.0, the RTP output can stream L8 (8-bits linear PCM) and L16 (16-bits linear PCM as on Audio CDs).

[majidaldo]

i know that but the error is: stream_out_rtp error: unsupported muxer type for RTP (only TS/PS) when i mux raw or wav.

[Rémi Denis-Courmont]

You should not be setting a mux in the first place...

[majidaldo]

ah i see. windows vlc has a bug where the streaming point-and-click interface is not updating the string output. i had to remove mux= manually.

nonetheless, :sout=#rtp{dst=htpc,port=1234,port-audio=0,port-video=-1}

give errors
main error: Invalid PCR value in ES_OUT_SET_(GROUP_)PCR !
stream_out_rtp error: cannot add this stream (unsupported codec: s16l)
main error: cannot create packetizer output (s16l)


thanks for the reply.

[Rémi Denis-Courmont]

Transcode to s16b

[majidaldo]

thanks that worked. but i had to basically ignore the interface and manually edit the command; ie. removing mux and changing to s16b in addition to specifying rtp port-audio equal to port (not sure if the developer team intended this) like so
:sout=#transcode{vcodec=none,acodec=s16b,ab=128,channels=2,samplerate=44100}:rtp{dst=htpc,port=1234,port-audio=1234,port-video=-1}

now, what to do about the audio skipping? :S the audio breaks very briefly a bit more than once a second. i'm on a wlan but i doubt that's a factor since i'm right next to the wireless router with plenty of bandwidth. i tried changing caching values but that didn't work.

on the server there is still.. main error: Invalid PCR value in ES_OUT_SET_(GROUP_)PCR ! (not sure if it's significant)
on the client, there are cycles cycles of this...
main warning: mixer start isn't output start (-12849)
main warning: output date isn't PTS date, requesting resampling (-46608)
main warning: buffer is 60133 in advance, triggering downsampling
main debug: End of audio preroll
main warning: mixer start isn't output start (-33944)
main warning: resampling stopped after 472000 usec (drift: -16711)
main debug: audio output is starving (191215), playing silence
main warning: output date isn't PTS date, requesting resampling (-41215)
main warning: buffer is 53611 in advance, triggering downsampling
main warning: resampling stopped after 428000 usec (drift: 53168)
main warning: buffer is 68724 in advance, triggering downsampling
main warning: resampling stopped after 376000 usec (drift: 16854)
main warning: buffer is 73566 in advance, triggering downsampling
main debug: End of audio preroll
main warning: mixer start isn't output start (-14578)
main warning: resampling stopped after 677000 usec (drift: 1)
main warning: buffer is 56713 in advance, triggering downsampling
main debug: audio output is starving (91322), playing silence
main warning: output date isn't PTS date, requesting resampling (-41322)
main warning: resampling stopped after 474000 usec (drift: 97702)
main warning: buffer is 113258 in advance, triggering downsampling
main debug: End of audio preroll
main warning: mixer start isn't output start (-47455)
main debug: audio output is starving (184510), playing silence
main warning: resampling stopped after 821000 usec (drift: -3961)
main debug: End of audio preroll
main warning: mixer start isn't output start (-16259)
main debug: audio output is starving (130596), playing silence
main debug: End of audio preroll
main warning: PTS is out of range (26663), dropping buffer
main warning: output PTS is out of range (30130), clearing out
main warning: PTS is out of range (26663), dropping buffer
main warning: PTS is out of range (-30457), dropping buffer
main warning: PTS is out of range (-30457), dropping buffer
main warning: PTS is out of range (-30457), dropping buffer
main warning: buffer is 43242 late, triggering upsampling
main warning: timing screwed, stopping resampling
main warning: buffer is 55464 late, triggering upsampling
main warning: resampling stopped after 219000 usec (drift: -22854)
main warning: buffer is 40031 late, triggering upsampling
main warning: resampling stopped after 458000 usec (drift: -33251)
main warning: buffer is 42888 late, triggering upsampling
main debug: End of audio preroll