[CentOS] recommended methods/software for videocasting

Thu Oct 8 17:16:38 UTC 2015
John R Pierce <pierce at hogranch.com>

On 10/8/2015 3:09 AM, ken wrote:
> An acquaintance is considering videocasting speakers at a conference 
> and using a Twitter product called Periscope.  I'd like to recommend 
> an open source solution.  While I've never offered videos over the 
> web, I have made audios available, and all it entailed was placing the 
> file on the website and putting its url on a visible webpage.  I 
> wouldn't think any more than that is required for video.  True?

video files are too big for that model.  an hour long video of medium 
good quality is often 1GB.   you want a 'player' that runs within 
browsers, probably using HTML5 as Flash is awful.   to feed this, you 
need a streaming protocol that knows how to throttle the video to a 
suitable data rate for the clients actual connection, and lets the 
viewer random hop to arbitrary points in the video stream without having 
to download the whole file before playing.     FOSS html5 video 
streaming servers exist but aren't easy to setup. nginx has a plugin for 

anyone streaming video for a significant number of viewers ends up 
having to get involved with a content delivery network, or they get 
killed with uplink speed requirements.    even 10 concurrent viewers of 
medium quality video can peg a 100baseT uplink, and most hosting 
providers will start charging transit fees per gigabyte if this happens 
too often.

> "Live" videocasting is likely a different animal.  How is this 
> accomplished?

painfully, and usually via proprietary transports.

> Also, which video formats are recommended-- FOSS of course preferred, 
> but a FOSS format for which there are readily available client apps on 
> the major platforms (MS, Android, OSX, Linux). 

with video files/streams you have 3 elements.   the container format, 
the video codec, and the audio codec.   while some container formats, 
like MKV, are open source, the codecs they contain rarely are, all the 
MPEG formats use patents, and its a  tangled mess.  MP4 h.264/x.264 aka 
AVC is probably the best compromise format for video quality and size.   
h.265/HEVC is even better but fewer clients can play it.   audio is 
usually AAC, AC3, or MP3, all of which are patent encumbered.   There 
are what I personally consider 'screwball' open source codecs like the 
Ogg family, and then there's the WebM streaming format used by html5, of 
which I know very little.

I finally came to the conclusion that the best way to host videos on a 
website was to load them onto vimeo or youtube, and embed their player 
html in your webpage, let THEM deal with the streaming aspects and 

john r pierce, recycling bits in santa cruz