Capturing nd outputting video simultaneously

Using media express, how can I capture live video that is being imported into my intensity pro capture card AND at the same time export the same live video to another pc or projector without lag? I have good windows PCs

Why bother? Put a distribution amplifier before the intensity pro.

You don't need to do anything, really. Just plug your projector into the output of the Intensity Pro. There should not be any lag.

[Chris Pearse]

This is correct. Any signal you are inputting into the Intensity Pro loops back out of the outputs. For example, if you are inputting HDMI, the same signal will output via HDMI and analog. You shouldn't see any latency with this either.

I can't plug into the projectors directly Because there are no left inputs. However, I can plug into the pc that controls output to projector via hdmi through another blackmagic intensity pro card. So my problem is that I need some software that recognizes the capture card and can stream it full screen thus ultimately on a projector. I tried using vlc streaming but just get a black screen.

vicgli05,

On Windows the fastest and simplest way to view video ingest into a Decklink/Intensity card is by using Direct Show.

There is a free tool called Graph Studio which will let you build "graphs" to do whatever you like with the video. It's also open-source, so if you are a developer (or know one), you can change anything you don't like.

http://blog.monogram.sk/janos/tools/monogram-graphstudio/

So to get input from a Card and send it to a Video Mixing Renderer which you can display in a window, full screen or not. you would build a graph which looks like:



However, there is one problem you should be aware of, that I simply cannot believe I am still talking about. BMD don't seem to understand how to handle interlaced video on Windows. They continue, even in their latest WDM components to report interlaced video with the wrong data structures, and thus many 3rd party filters will see 1920x1080@59.94/50Hz as a progressive picture, and "most" hardware de-interlace engines will not process the video, and thus you'll need to get a 3rd party filter to change the frame buffer headers, if you need to de-interlace between ingest and render. It's madness I know, but this is BMD.... it's all part of the fun!!!



Good Luck.

John

John,

Thanks for the help. I found the rendered and the avi filter. How do I build the blackmagic capture on the graph?

THanks

You could try something like this, it'll capture and display at the same time.

You could try something like this, it'll capture and display at the same time.

Thanks I can make all the items on the graph except the first (Blackmagic WDM Capture (orange box)). How do I import a blackmagic capture item?

From the Insert Filter Menu:

Select "WDM Streaming Capture Devices"



It'll be on this short list



But, as always, the BMD code/software is very slightly buggy, so please ensure you set the properties of the filter (right-mouse-click on filter/Select Properties -to set the video mode, audio settings etc..) BEFORE you connect the output pins of the BMD Capture to the SmartTee and AVIMuxer.

Looks like I don't have WDM Capture on my filter list. I have Decklink Video Capture. Would that work?

Have you installed the latest Blackmagic Desktop Video software? I believe WMD was added for some devices not long ago.

Right so I installed v9.5 and I can now find the WDM filter. OK GUYS, IT WORKED! It streams the video to the rendered. The only problem is that I need to make it full, full screen. The top menu bar is still visible and the start icons below are visible. Any shortcuts for the video renderer for fullscreen?

Thanks

How are you streaming (which software)? Sounds like you are not streaming the actual source video but you are doing it from a screen capture of the video?

Here is my setup that streams currently video but not completely full screen.

Graph Setup

ss.png (98.57 KiB) Viewed 9947 times

Here is a SS of the video stream in VMR 9. Of course the lower bar can disappear if I stream to another monitor but, the top bar will still be there.

ss2.jpg (222.03 KiB) Viewed 9947 times

Not familiar with that tool and how it streams. Is there any reason why you can't use a "proper" streaming encoder - such as Flash Media Live Encoder? You would not then need that GraphEdit tool.

I think I may be missing something with your workflow here.

Not familiar with that tool and how it streams. Is there any reason why you can't use a "proper" streaming encoder - such as Flash Media Live Encoder? You would not then need that GraphEdit tool.

I think I may be missing something with your workflow here.

Isn't FMLE for streaming online, or to hard drive? I am trying to stream back to a monitor full screen. Also FMLE crashes like nuts with BM.

vicgli05,

This isn't going to be much help, but you need to call this function

http://msdn.microsoft.com/en-gb/library/windows/desktop/ms633545(v=vs.85).aspx

to resize and position the window, such that the client area of the window is exactly the size of your screen, and the top and left are offset by the height and width of the window borders (i.e. negative top left cordinates).

In order to do this you must enumerate the active windows to pick-up the window handle. It's not complicated or particularly difficult to do, but unless you can write a script to do this, you are going to struggle with this information alone.

I did originally think you were trying to do a recording at the same time as displaying the screen, and hence why I suggested this tool to you. If all you want to do is preview the incoming video full screen then VLC is probably your best approach.

Now you have the latest drivers installed, and since you aren't recording, why not try that tool again. If not, I'll write you the script you need next week, but I am too tied up this week to do this.

Best Wishes

John

Ahh.. not heard of the term "streaming" to mean displaying on a monitor. So... yeah... I'm thinking of something completely different.

EDIT: typo

Thanks John.

I would use vlc. It's sort of my last resort and I did get it to work, however, there is quite noticeable lag in vlc streaming. My pc is pretty good hardware wise and Idk if its the 15' hdmi cable from camera to capture card that's causing the lag.

There is no lag with the graph software. So a script at your convenience would be helpful. Thanks

I may have lost the thread of the conversation here a little... but why do you need to use VLC to "stream" to your monitor?

Didn't this http://forum.blackmagicdesign.com/viewtopic.php?f=4&t=3666#p23819 answer your question already on how to capture and output to another monitor simultaneously without any lag?

You mentioned later that you don't have any "inputs" left...and then mentioned you need to "Stream" the output to another computer - and that computer is then connected to the projector.

So are you actually capturing on PC #1... then you are trying to stream (using something like VLC) over to PC #2 and you are viewing that full screen and that is being displayed on your projector?

I think a diagram might be in order to get exactly what you are doing.

But... if you really are "streaming" from one PC to another - you will never ever be able to do that without a sizeable delay. It simply is not possible to do that without any lag.

I may have lost the thread of the conversation here a little... but why do you need to use VLC to "stream" to your monitor?

Didn't this http://forum.blackmagicdesign.com/viewtopic.php?f=4&t=3666#p23819 answer your question already on how to capture and output to another monitor simultaneously without any lag?

You mentioned later that you don't have any "inputs" left...and then mentioned you need to "Stream" the output to another computer - and that computer is then connected to the projector.

So are you actually capturing on PC #1... then you are trying to stream (using something like VLC) over to PC #2 and you are viewing that full screen and that is being displayed on your projector?

I think a diagram might be in order to get exactly what you are doing.

But... if you really are "streaming" from one PC to another - you will never ever be able to do that without a sizeable delay. It simply is not possible to do that without any lag.

Liam you are correct about capturing and streaming to different PC's. I can't directly plug into the projector (which would cause no lag apparently). I am using an HDMI distribution amp to send the camera signal to pc #2 which is connected to projectors and will stream video to them. PC #1 is just for capturing purpose. I have 2 BM IP cards conected to both pcs, one for capture, one for streaming. I know it's not the most efficient way of doing this, which is giving me problems. It would have been MUCH easier to directly connect to the projector from PC #1, but its just not possible (details I wont bore you with). PC #2 displays text, songs to the projectors and video as well. Which is another thing I will have to figure out; is how to work with the projector software(text) and coming up with a way to display video.

Just an update on VLC. I fixed the "lag" issue while streaming. I went to Tools, Preferences, Show All, Input/codecs, and changed the Live Capture Caching to 50 ms instead of 300ms and bam, no lag. Idk if that will cause me any problems in quality but I will see.

I am using an HDMI distribution amp to send the camera signal to pc #2 which is connected to projectors and will stream video to them. PC #1 is just for capturing purpose. I have 2 BM IP cards conected to both pcs, one for capture, one for streaming. I know it's not the most efficient way of doing this, which is giving me problems. It would have been MUCH easier to directly connect to the projector from PC #1, but its just not possible (details I wont bore you with). PC #2 displays text, songs to the projectors and video as well. Which is another thing I will have to figure out; is how to work with the projector software(text) and coming up with a way to display video.

You say that both of your PC's have 2 x IP cards one used for capture and the other used for "streaming".

Forgive me again. When you say "streaming" do you actually mean what is the accepted definition of "streaming"... that is when you are running some kind of encoding software that takes a video signal - encodes it - and then streams that out to some other computer. What you seem to variously be referencing is when you simply take the output of the IP and "display" that on a projector.

I've got a sneaky suspicion that if you shared your entire signal path and what you are trying to achieve another solution might be available.

For instance when you mention things like this:

PC #2 displays text, songs to the projectors and video as well. Which is another thing I will have to figure out; is how to work with the projector software(text) and coming up with a way to display video.

What it sounds like is you really need to be using a switcher - something like the ATEM TVS - and using the Luma Key function to overlay the text on top of the video.

I could be wrong... but I really do feel I am missing an essential part of the picture.

vicgli05,

Great news VLC is working the way you want.

I agree with Liam, if you could perhaps share as much detail as you can, about exactly what you are trying to achieve, someone here will be able to recommend the right solution first time.

If not, I think I have an idea that could help you, but I need a little time to work on it next week.

For example if you just want to combine Text with ingested video and are happy to send that to your projector on the PC graphics card output, you can hook up your text data to one of the other input pins on the video mixing renderer, and I think there is probably a way to send subtitles into VLC (although never done it myself).

Liam, "Streaming" as a technical term, or just as an adjective, even in the broadcast industry, let alone all the others, tends to get used to describe any kind of data making it's way from A to B. So you've always gotta take that word to cover a wide range of possibilities! There isn't really "an accepted definition" of what a stream should contain.

I know of cases where an HD-SDI signal has been "streamed" uncompressed over two trunked networked connections, bit stupid I thought at the time, but there are always reasons. The latency in these cases can be reduced to virtually nothing if you are using switches with high enough backplane speeds (Cisco Catalysts 6500s for example are pretty good), or just have one or two streams running. It not unsual to stream individual frames of JPEGs over local area networks, which again can be streamed with minimal latency, multicast video streaming can be implemented differently again. You can even get pretty good latency with H.264/AVC if you reduce the GOP length dramatically (bit rates / quality suffers though).

It seems like the TVS might be a pretty expensive way of combining one video stream with some text, especially when this user already has access to, or owns, Intensity cards.

Cheers

John

John and Liam,

I apologize for not being more clearer. When I say streaming, I mean very simply DISPLAYING the video full screen to a monitor or project. That's it. Not to another pc or online (at least not yet). Also again apologize for not being more clear but this is for a church. I didn't mean I wanted to combine text with video. I meant that the pc #2 is connected to a projector display and it displays Bible's verses(text) and songs. We are now trying to get it to display the video source coming from the hdmi distribution amp to the blackmagic intensity pro card on pc #2. We can forget pc#1 as its sole purpose is for capturing which I have no problems technically doing.

Hope that didn't leave you guys even more confused