ATEM Television Studio- H.264 streaming...

Hello!

Firstly, I must confess I am a newbie in distress!

I am working on a project which we want to stream H.264 down a 2MB LAN connection but using as much HD video as possible....with sound...

We are looking at purchasing the ATEM Television Studio for it's encoding function. Pretty simple setup so far- 2x HD cams, BM encoder, 2 mac computers and a 2MB LAN network linking the encoder and macs together. All on a clean corporate network.

First question- is a clean 2MB connection good enough for a steady HD live stream?

Second question- which software is best for the decoding on mac computers? I have only looked at VLC so far...

Many thanks in advance!

Davidrth

So if i understand you correctly, you are looking to stream an H.264 broadcast internally?

Also, im assuming by MB you are referring to megaBYTES (MB) and not megaBITS (Mb)? People often get confused with the difference, even the reps at cable companies (in my experience) often dont know the difference, which is significant.

a full 2 clean mega bytes......

thanks

Well, in that case, the only streaming server that I know you can use for free is QuickTime Broadcaster, if you want to just stream to your LAN. Honestly, this would only be a good solution if you are just targeting one destination.

FMLE or others require that you connect to a streaming server. Which means you would have to purchase streaming server encoders like wowza or adobe's encoder, etc.

Download:
http://support.apple.com/kb/DL764?viewlocale=en_US&locale=en_US

Heres how to set it up:
http://www.interrupt19.com/2009/06/08/broadcast-streaming-video-quicktime-broadcaster/

Thanks for that link Jeff,

Not sure if you got the right end of the stick. I am looking to find out if its possible for the ATEM unit to send a H.264 signal down a 2 mega byte LAN cable and still decode full HD at the other end?

So you want a direct from ATEM over cat5 solution? If its not going through a switch and is less than a 300' run then I would look at something like these:
http://www.markertek.com/CATV-Headend-Interface/CAT-5-Transmission-Systems/HDMI-Over-CAT5-Systems/Gefen-Inc/HDMI-13-CAT5-ELR.xhtml

You would come out of the hdmi program output into the conversion. Its not h.264, it would be the full resolution of the switcher, just transmitted over cat5. On the ATEM TVS the h.264 is only available via the USB port when connected to a computer, I think thats where you may have confused me.

In a round about way.. yes. I have access to a network link between 2 building 1 mile apart. The link is actually fibre but is limited to 2MB in the building which can't be changed.

Ah, details.

So does this fiber connection host anything else? If its just an empty fiber, then take the HD/SDI from the ATEM and convert it to fiber, send it over the link, and then convert it to whatever you need on the other end.

Or are you trying to send your video feed through your internal network, to your switch, over the fiber to the other building, through another switch, to a remote computer/display? If this is the case you are better off just streaming it to the internet via service like livestream or ustream. You would have to have a computer host on each end, one to stream and one to consume/output. This method will not allow you to 'upconvert' the h.264 into some full resolution, although if you streamed at a high resolution it wouldn't be bad, like watching hulu or the like in 'HD'.

The fibre is already converted at each end to cat5 in building 1(encode) and building 2 (decode). I don't have direct access to the fibre. Just using 2MB worth of it.

cams - Encoder to cat5- network-fibre( under the road)-network- cat5 to laptop doing the decoding- HD connector - cinema projector. All of that is limited at 2MB.

Will HD come out of the laptop on the decoding part?

Am very new to all this rather smart but over my head equipment. Sharp learning curve...

Will HD come out of the laptop on the decoding part?

In terms of lines of resolution, yes. Barring that you encode it at 720p or 1080i (based on your output from the ATEM)

In terms of video bit rate, not technically. I would tinker with figuring out how high you can get it without dropping or buffering.

If you use a streaming service the quality is dependent on your upload speed provided by your internet provider. If you go with the quicktime broadcaster point-to-point solution, then the cap is only your 2MB connection.

Now you cant use a cat5 extender to do a direct feed through a switch, let alone 1 mile. You will have to stream it in some manner.

Think the next step is to get things setup with a HD video on loop and test it. Play about settings etc.

Thanks for help Jeff. Watch this space!

are U sure , that its 2MB ? lan speed is everytime in mb (megabits) per second (mbps) ..

if its 2MB/s = 16mbps , than its really good for HD stream ..

the 2MB info came from the head of networks after doing tests... I guessing this info is correct.

Streaming VPN is all about providing ultra fast VPN network services, which are optimized the best for streaming multimedia. I enjoy loads of their services with unbeatable price tags and high end customer services.

So you need to be encoding and decoding over a network, no hardware convertors. If you only need to decode from a single machine you have a few options, quicktime broadcaster or VLC can do this. You can also go a little more in depth and make a program using either FFMPEG or Gstreamer libraries. I recently created a lan based multi client video chat software that used the Gstreamer library. I chose UDP encoding which has less latency.

You will have a visible decrease in quality as the stream is encoded and decoded. You will also have some tinkering to get AV sync right with a high bandwidth application. I ended up using apples audioNetSend and NetReceive plugins to stream high quality audio as I could not find a good working balance with in sync audio and video along with high quality transmission.

You may wish to go with a hardware solution instead, something like this

http://www.qvidium.com/products.html
or

http://www.antrica.com/products/full-hd ... nt-32000a/

Or there are several axis products. As yet many of the more affordable solutions are not designed for high quality, just for viewing. However if you have the cash you can get things that look great.

A good hardware solution will be much less of a pain than using software as they should just go.

the 2MB info came from the head of networks after doing tests... I guessing this info is correct.

I think there may be a terminology problem here. For streaming video we measure it in the amount of X data per second. So your acronym should be 2MBps. But the capitalization of the bitrate is important too. 2MB is very, very different than 2MBps which is very different than 2Mbps. Tricky since they all look the same.

If it helps at all, here is how each would break down for you:

If you're allowed only 2MB (2 Mega Bytes) of data then at a 1.5Mbps encode you'll only get 10 seconds of video before you're out of bandwidth. At 256Kbps you can get up to 1 minute. Neither of these numbers are really high enough for great HD quality. 2MB indicates the size of a file and not the amount of data down a line. This is not the norm, but it is possible for them to rate limit you based on how much data you have used. Very unlikely scenario though.

If you're allowed 2Mbps (2 Mega Bits Per Second) of data then you can stream low motion clips in high definition. High motion clips you'll probably want to dumb down to 640x360. To determine this you'll want to run a few tests and see how it looks. I also suggest overhead room, so I would run the stream at no higher than 1.5Mbps.

If you're allowed 2MBps (2 Mega Bytes Per Second) which is 16Mbps (16 Mega Bits Per Second) then you'll have enough for a good HD encode with full motion. Your encoders will all be set in Mbps (bits per second) so you'll want to target something like 10Mbps to give yourself overhead room.