Hello.

There is a new task called vMixNDIHelper.exe which first does not consume any CPU power but then start to use 23-30% of the CPU power even I have not NDI enabled.

Tested with vMix 17.0.0.67

Chap

NDI external output seems to be always active (if it is checked in the external output options, of course), even when the "External" button is not activated/red.

Is it meant to be that way or should it be possible to turn NDI off with the external button?

This may happen if you are using "vMix Video" in some other program outside of vMix and the streaming quality settings in vMix were changed, is this the case for you?
If so close all programs and restart and the stream should show the video signal again.

What is the GPU setup like on the laptop? Does it use hybrid graphics of some kind? Maybe running vMix Desktop Capture on the GPU in the Nvidia control in this case may fix the problem.

By now I have had time to experiment wildly (meaning rather randomly, not scientifically) with NDI on different desktops and laptops, Win 7, 8.1 and 10.

Generally the NDI part works, although I find it quite taxing on CPU and Graphics card. Typically tried with 1280x720 @ 50p. For example four NDI sources on a moderately equipped laptop, recording and streaming is too much.
Have not tested on our powerful PC's yet, as these are for production. Will do later on.

Not so successful over WiFi (Asus router). But that's not so surprising, given how packed our WiFi band is here ;)

I guess getting a few frame drops here and there is what one might expect. More frame drops when using NDI desktop capture.

I get a feeling that the thumbnails for the NDI sources shown when adding an Input is not properly updated. For example, quite frequently I get a thumbnail from what was in the NDI source's vMix Output long before.

If the network cable is disconnected, the receiver PC's NDI Input video freezes. Upon reconnect audio takes about 15 seconds to get back in sync. But to get video back I have to left-click in the Input's preview to select another NDI source, then select back the proper NDI source.

If an NDI video Input is changed to an NDI audio source, a still video frame remains in the Input's preview.

Regarding latency. I tested listening with a headset, left channel the source PC and right channel the receiver PC. A noticeable, but not unbearable delay. On the border to sound like an echo. But using a second NDI sourced PC for IMAG might not work, due to the added latency. I also did a camera recording of the sender's (playing BBC's sync test at 25 fps) and receiver's screens. Measured the latency to 2 frames (@ 25p).

Small note regarding the NDI desktop capture app. If Window's display is set to show apps etc at less than 100% size, then the text "Ready...fps" in the capture app is not properly resized. Also wonder why max 50 fps is not an option?

Hope this is useful info for debugging/improvements. I am not complaining, rather happy with all the new possibilities :)

I'm trying to send my 8 inputs over NDI to another vmix, but it maxes out at 5 inputs. When I add another input, the inputs start blinking random and the network traffic drops until I close at least 2 inputs. Then it recovers and I can add one NDI source again and it keeps working.

I did iperf between both systems, they can easily get twice the bandwith trough using iperf.

Cpu usage is below critical levels when this happens. Sending machine 35%, receiving machine 60%, rendertimes under 10 msec. Cpu usage values taken from windows task manager so nothing else using cpu.

I did try with windows firewall off and another gigabit switch.

Do you have any idea where this bottleneck might be? I know if the receiving machine has 60% cpu usage with 5 NDI camera's coming in, there is not much resources left if I would get to 8, but why do I hit a limit before getting there?

thanks martin will give it a try. Laptop has Intel HD 3000 graphics with Nvidia 2.5gb Geforce GT 540m as the secondary graphics card which pretty standard combo on laptops other then higher new Nvidia and Intel GPU's and recent laptops.


---updated---

Same error after selecting the Desktop Capture to use the Nvidia GPU.

System.OverflowException: Arithmetic operation resulted in an overflow.
at vMixDesktopCaptureLibrary.ImageUtils.CopyRGBA(IntPtr src, Int32 srcStride, Int32 srcX, Int32 srcY, IntPtr dst, Int32 dstStride, Size sz)
at vMixDesktopCaptureLibrary.DXGICapture.Capture(DesktopCaptureData& d, Rectangle r)
at vMixDesktopCaptureLibrary.DesktopCaptureServer._CaptureThread()

It works for about 5 secs and then freezes then the error above. NDI video works great over wifi the for laptops webcam.

CPU on send and receive are the same, both Xeon E5-1620 running static at 4ghz.
I did turn HT off for the receiving system and that shows indeed the processor maxes out at four ndi inputs. (did have to activate again because of it)

So this is clear but I have to be honest that I expected more from it. The sending machine is at 30% with 5-6 ndi outputs, while the receiving machine needs a 4Ghz core per incoming NDI stream. Why is decoding so much more intensive compared to the encoding?

Hi Martin. Yes can confirm this one works (have a youtube video playing the laptop and no lag. Happy Easter.
Do I replace the one in the vmix directory with this one? or wait until further builds of Vmix 17?

Thanks.

You can use the Nvidia control panel to specify the following application to use the dedicated GPU:
"C:\Program Files (x86)\vMix\browser\CefBrowserInstance.exe"

This program is what is used in the background for web pages.