The VideoLAN Forums

Hi,

I have a file that VLC Codec details tell me is H264, and the Playlist says the duration is 2:32. The file is 96395895 bytes, so the encoded avg bitrate is just over 5 Mbps.

I want to send this file over an RTP stream across a narrow-band network.

Q1. It seems to me that VLC opens the file, reads the bytes, and always decompresses it. Is this correct?

When used to stream this way the resulting network stream is ~ 100 Mbps. One could recode (if one transcodes from H264 to H264 is that really transcoding?) to H264, but the sending computer is not fast enough to do this.

Q2. Is there a vlc command line that can be used that will transport the H264 video from the file, over RTP with a "small" bit rate, that does not require decoding/recoding the video?

By small bit rate, I mean the network data rate approximately equals filesize/file duration + RTP+UDP+IP overhead per packet. (lets guess +10%)
Is there also some mux overhead required? [ I cannot see this being 90 Mbps. ]

If not VLC, is there other software that might do what I'm wanting?

Thanks for any insight you can provide,
Don

Q1. It seems to me that VLC opens the file, reads the bytes, and always decompresses it. Is this correct?

No. Only decompresses for display.

Q2. Is there a vlc command line that can be used that will transport the H264 video from the file, over RTP with a "small" bit rate, that does not require decoding/recoding the video?

Same as, without transcode{}, only std{}
Documentation:Streaming_HowTo_New/

Thanks, That sounds exactly like what I need.

But I think I need help with the exact command line.

I just tried the following using vlc 2.2.6 on Windows:


1) vlc -vvv Desktop\video720q10.mp4 :sout="#standard{access=rtp,mux=ts,port=5004,dst=192.168.20.47}"

vlc did not report any errors, but no data was streamed to the network. ???

2) FYI, video720q10.mp4 was made using the mpeg4 codec at video quality 10.

3) If I use the following, data is streamed to the network, and the bitrate is <= 4Mbps (as required) and the video is displayed correctly at the receiving end.

vlc -vvv Desktop\video720q10.mp4 :sout="#rtp{mux=ts,port=5004,dst=192.168.20.47}"

4) We would like to use H264 for improved video quality for the same filesize (which I thought should result in the same bitrate on the network) . But if I use command 3) and change the video file to one that uses the H264 codec the network bitrate is almost 100 Mbps, and the video will not play on the receiving end.

Any suggestions on how to proceed?

Thanks again,
Don