The VideoLAN Forums

Posted: **02 May 2004 22:22**

Hello,
I'm trying to transcode an HTTP stream I have coming out of my VDR system. I'm trying to view this over the internet [in windows media player], after having been transcoded. I need to squeeze the stream down to about 100kbps. I tried setting all the bitrates lower and lower, until I started noticing it wasn't affecting the bitrate that WINDOWS MEDIA was reporting [which was 493KBPS]. So as you can imagine, I get 1 second of video, and 20 seconds of BUFFERING. Also, I cannot hear any audio. Anyone have any experience with this? Here is my command:

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vlc -vvv http://127.0.0.1:23/229 --sout '#transcode{vcodec=DIV3,vb=64,scale=0.5,acodec=mpa,ab=16,channels=1}:std{access=mmsh,mux=asfh,url=:1234}'

Posted: **02 May 2004 23:04**

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vlc -vvv http://127.0.0.1:23/229 --sout '#transcode{vcodec=DIV3,vb=64,scale=0.5,acodec=mpa,ab=16,channels=1}:std{access=mmsh,mux=asfh,url=:1234}'

I believe it should be acodec=mpga. That should help on the sound issue.
If the bitrate is still too high for streaming over the internet, try scaling the stream. At some point the Codec cannot lower the bitrate anymore if the resolution is not decreased.

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vlc -vvv http://127.0.0.1:23/229 --sout '#transcode{vcodec=DIV3,vb=64,acodec=mpga,ab=16,channels=1,width=320,height=240}:std{access=mmsh,mux=asfh,url=:1234}'

Posted: **02 May 2004 23:39**

Thanks very much for your advice!

I still get no sound [when I go to FILE->PROPORTIES in WMP, under AUDIO it shows nothing [as if it's not receiving it].

The video has gotten much better...and now WMP reports 30kbps...but the funny thing is it still seems to buffer every 10 seconds or so...and I know it's not my network because I can connect to my DVB HTTP stream natively and get smooth video and audio [which are at WAY HIGHER bitrates].

I'm curious...is there any way to set the FRAMES PER SECOND? I'm encoding NTSC, so I'd love to set the bitrate at 15FPS if possible.

As far as the audio, it looks like ffmpeg is having a problem:

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[00000194] main packetizer debug: probing 20 candidates
[00000070] main module debug: using packetizer module "mpeg_audio"
[00000194] main packetizer debug: thread 114696 (decoder) created at priority 0 (src/input/input_dec.c:153)
[00000194] mpeg_audio packetizer: MPGA channels:2 samplerate:48000 bitrate:192
[00000182] main stream output debug: adding a new input
[00000183] stream_out_transcode private debug: creating audio transcoding from fcc=`mpga' to fcc=`mpga'
[00000195] main encoder debug: looking for encoder module
[00000195] main encoder debug: probing 4 candidates
[00000195] ffmpeg encoder debug: libavcodec initialized (interface 4703 )
[00000195] ffmpeg encoder error: cannot open encoder
[00000195] ffmpeg encoder debug: libavcodec already initialized
[00000195] ffmpeg encoder error: cannot open encoder
[00000183] stream_out_transcode private error: cannot open encoder
[00000183] stream_out_transcode private error: cannot create audio chain
[00000194] main packetizer error: cannot create packetizer output
[00000193] packetizer_mpegvideo packetizer debug: need a starting pts/dts
[00000182] main stream output debug: adding a new input
[00000183] stream_out_transcode private debug: creating video transcoding from fcc=`mpgv' to fcc=`DIV3'
[00000196] main encoder debug: looking for encoder module
[00000196] main encoder debug: probing 4 candidates
[00000196] ffmpeg encoder debug: libavcodec already initialized
[00000196] ffmpeg encoder debug: found encoder MS MPEG-4 Video v3
[00000015] main module debug: using encoder module "ffmpeg"
[00000015] main module debug: unlocking module "ffmpeg"
[00000182] main stream output warning: trying to send non-dated packet to stream output!
[00000196] main encoder debug: looking for encoder module
[00000196] main encoder debug: probing 4 candidates
[00000196] ffmpeg encoder debug: libavcodec already initialized
[00000196] ffmpeg encoder debug: found encoder MS MPEG-4 Video v3
[00000015] main module debug: using encoder module "ffmpeg"

Posted: **02 May 2004 23:59**

As far as I know, there is no way to use vlc to change the frames per second. Mencoder (part of MPlayer http://www.mplayerhq.hu) can change the frames per seconds but it cannot work during streaming I suppose.

Instead you need to transcode a file with Mencoder and then stream this transcoded file with vlc.

Concerning sound encoding: use a higher bitrate for audio. ab=32 should work.

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Streaming to WINDOWS MEDIA will not go below 493kbps

Streaming to WINDOWS MEDIA will not go below 493kbps

Re: Streaming to WINDOWS MEDIA will not go below 493kbps