Thread: multiple DVB-S Cards PC resources usage

Hi all
this is my first post (yeih!)

We are setting a streaming center in Tennessee and will be streaming some 6
FTA channels. For these we are thinking of getting some 6 PCI DVB-S cards.
We are non-profit, so we try to keep our costs to the minimum.

I have a couple of questions and I am sure some of you have answers (you've been there before, done that before...)

The questions:

1) We have several 2.4 Ghz PCs with 512 Mb RAM (Windows based). The PC(s) will be receiving the signal via PCI DVB-S cards and encode it with locally installed software (adobe flash media live encoder). I wonder how PCU and memory intensive is the simultaneous use of say 2-4 PCI DBV-S cards (on one PC). Has anyone any idea?

2) Any other potential problems you see with this approach (as opposed to using, for example, USB DVB-S Receivers)? The PCs will work 24hx7.

3) Also I was thinking of purchasing generic (no namers) cards from Hong Kong, any opinion on making 2-4 PCI GENERIC cards work simultaneously? I have seen that there are issues with PCI cards of different brands: with drivers, combination of different brands, using different TV viewing software, etc.

But most of the threads I've read have to do with watching simultaneously or watching and recording different channels simultaneously. We are just encoding different channels simultaneously.

I thank you in advance for your answers.

So, you are going to receive multiple FTA channels, and then do what?
Stream them over the internet?


I have some old 2.4ghz P4's and wouldn't expect much from them on 512k of ram.
The good new is, memory is cheap.
Don't think I can offer much seat-of-the-pants advice, though.


If you don't get any better answers soon, take a look at these two threads:

- short thread, might give some insight

- kinda long, but skip to Pendragon's comments and see if they are helpful.

This isn't an easy question to answer because what you're describing isn't a common setup for FTA use. I have been working on a related project to deploy a bunch of PCI/USB receivers under central control for the distribution of programming to multiple viewing locations around the house. That should be easier than it is.

At the moment I have four DVB World 2104 USB receivers and a TechnoTrend 3200 PCI card. In terms of Windows, there are driver issues with the USB receivers that prevent using more than one per system. Each can be independently tuned, but I can only get one to stream data. I can get the TechnoTrend to work with one USB receiver. This is really a peeve of mine. Does anyone know of a DVB-S2 USB or PCI receiver that can be used in multiples on the same machine?

The Windows machine has an AMD X2 5600 processor and 4 GB of memory. It serves many other purposes, and the two FTA tuners have a minimal impact. When I run DVB Dream as the tuner app, it uses about 100 MB for each DVB World tuner instance, but only 30 MB for the TechnoTrend. When idle, each DVB Dream uses around 2% of the CPU and this increases to say 5% when streaming.

I'll probably continue to work to find better ways of getting more tuners to work on Windows. But as I'm currently blocked, I have one USB box on another Windows machine and the other two USB boxes are on two Linux servers for experimental use. I haven't had the time to do this right, but I have written a little code to get the Linux units to function at a minimal level so I can use them in my system. It's not particularly general and if I ever find the time, one possibility is to move all the USB/PCI units under Linux control. At least that way I'm not dependent on someone else to write decent drivers/apps.

Thank you guys for your answers.

To Anole: yes we will be receiving the signal, encode it in flash and send it to a stream server. We'll do this for 6 signals (5 TVs / 1 radio), and as it looks like, I'll probably use 6 PCs to do this...

To Pendragon: I'd say, we are definitely not planning anything near the complexity you have at home! (I've read the threads Anole kindly provided).

From your answer I gather that PCI cards might be better performing than USB receivers. This is good to know. We may have to go with one PC per receiver, to keep things simple and straight forward. Especially since we are working with legacy PCs.

We will be using Windows because the Flash Media Live Encoder 3 works on Windows, but I have not seen anything written to make it work for Linux (to my knowledge). Also, for support (there will be several supporting), it is easier that way.

I guess at this stage we just have to try with this set up and see how it goes...

Thanks again for your time and answers.

I currently already stream channel over the net not using dvb-s but think can help a little.

With Flash Media Encoder most important is cpu processing power if cpu cannot keep up you will have degradation in quality or drop frames.
You will have to dedicate one pc per stream and use H.264 option for enconding more cpu intensive but lower bandwith consumption.

Upgrade your ram to at least 1GB & i would recommended 2GB best option.
2.4ghz will be okay just do not try go over 21fps or you will run into issues.

Thank you RtpiFan for your input,
that adds a couple more important bits of information.

We are currently testing with the PCs, and yes we plan to stream H.264 at 20 Fps. In the past I have had problems with the Flash Media Live Encoder 3, I am not sure how it manages memory, but I guess sometimes is a little buggy.

However, I gather you would agree with Pendragon's statements that the sat PCI receiver cards are not severely tasking CPU or memory, right?

This was one of the initial questions in starting this thread, and the answers I am receiving seem to lean in this direction: the PCI receiver card is not heavy on resources. The software handling the card (be it a viewer application) or in my case an flash encoder application, can be the big users of CPU / memory resources. Thanks for your input.

My twinhan use very little cpu ressource unless it's an hd feed but 3ghz based system.
But Pendragon's statements is 100% correct at least in my experience with twinhan and i am rather new to it.

FME(Adobe) is buggy as hell but it works set auto adjust features and set buffer 5 sec's found that it helps alot with disconnect's.
Set option degrade quality not drop frames seem easier for recover and ramp quality back up for it.
Remember fast action scenes will be at disadvantage but it will still perform well.
It will reconnect matter of second's at worst a few minutes with that buffer setting.

Also make sure audio and video are synced as FME as problems with this if encounter this issue let me know and i will point you in the right direction to resolved the issue.

Now make sure your routers can handle traffic 24/7 mine require a reboot every couple weeks.

Thanks RtpiFan for the confirmation on the dvb cards. And we will not be receiving HD anyways.

Thank you for the other points as well. We are in a testing phase, so any input will save money and time in the future.

I was aware of the router's issue (with 24/7 continued streaming problems), but not aware of any sync problems with FME Video/Audio. But I will take note of your points and get back if needed.

So, in conclusion, the thread has pretty much settled my choice of going with PCI dvb-s cards (not USB receivers) and using one PCI receiver card per PC.

Whether we will have to upgrade/expand the legacy PC hardware is something that is being tested right now. I'll post further developments of notice, on this thread. Thanks to all, again.

Look at Adobe Flash Media Live Encoder 3 Min. System Requirements
here

. Just keep in mind,
Flash Media Live Encoder supports only raw data from video and audio devices. The supported raw video formats include I420, YV12, YUY2, UYVY, RGB24, and RGB32.


This means, you need to decode MPEG2 signal first, and it takes extra processing power. You can unload MPEG decoding & encoding tasks to your Graphics Card Processor, if you use suitable Card and DVB soft. That can make your current setup sufficient for 1 card per PC. You can try even 2 Cards per PC, as TeVii DVB-S/S2 card drivers support multiple cards per a PC.