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matthias-web
03-25-2016, 01:10 AM
Dear all,

Most of NDI users will use the NDI tool "scan converter" as instant replacement for iVGA.

In the moment there is one option to enable "high framerate".
But for some content framerate is not so important, but the quality (especially when transmitting text with smaller fonts).

How about to offer these options in a future version:

Framerate: low, normal, high
Quality: low, normal, high

For example if I want to transmit a screen with smaller fonts which is refreshing only every second (e.g. scoreboard), i would choose "low framerate" and "high quality" to get the best results.

Second: an additional option for "whole screen capture" could be handy as well for some scenarios.

With these features NDI scan converter would meet all iVGA features and be of course being much superior with using NDI.
Many thanks for maybe taking into consideration!

Best regards,
Matthias

kanep
03-25-2016, 08:36 AM
Is your concern the performance of the system with NDI Scan Converter on it? Or network bandwidth?

NDI Scan Converter captures applications windows before they are composited together on the Window's desktop. Performance overhead is lower than iVGA in this regard while still providing higher frame rates.

As for network bandwidth, NDI is very efficient, I can't think of any reason I wouldn't choose high quality if there was a selection. Viewing in Task Manager, I did a test with three application windows being sent via NDI Scan Converter (YouTube full screen, PowerPoint and Adobe Reader, with NDI Scan Converter in High Frame Rate mode) and my Ethernet bandwidth was around 55 to 60 Mbits/sec. iVGA would probably be higher than that for just one video stream.

matthias-web
03-26-2016, 02:43 AM
The reason would be to get better quality when running NDI from older/weaker computers.

I made a comparison between different outputs from a screen with small fonts:

133119
(please see in full resolution 1920x800)

A: Older laptop HDMI out -> converted to HD SDI -> Tricaster SDI input
B: Older laptop iVGA Pro -> Tricaster AE v1 NET input
C: Older laptop NDI -> Tricaster AE v2 NDI input
D: Newer laptop NDI -> Tricaster AE v2 NDI input

Conclusions:

The NDI signal from the stronger laptop has perfect quality - not a bit worse than the HDMI signal.
However, from a weaker laptop the iVGA Pro signal is beating the NDI scan converter.

Especially in these kind of scenarios (when not video, but text is transmitted) the NDI scan converter option "higher framerate" does not help, I would gladly exchange to have only 2 fps but a higher picture quality. That's why I think these optional settings of framerate/quality would be useful to enable existing (older) equipment for NDI and send iVGA to legacy without worries...

Best regards,
Matthias

livepad
03-29-2016, 10:30 AM
The reason would be to get better quality when running NDI from older/weaker computers.

I made a comparison between different outputs from a screen with small fonts:

133119
(please see in full resolution 1920x800)

A: Older laptop HDMI out -> converted to HD SDI -> Tricaster SDI input
B: Older laptop iVGA Pro -> Tricaster AE v1 NET input
C: Older laptop NDI -> Tricaster AE v2 NDI input
D: Newer laptop NDI -> Tricaster AE v2 NDI input

Conclusions:

The NDI signal from the stronger laptop has perfect quality - not a bit worse than the HDMI signal.
However, from a weaker laptop the iVGA Pro signal is beating the NDI scan converter.

Especially in these kind of scenarios (when not video, but text is transmitted) the NDI scan converter option "higher framerate" does not help, I would gladly exchange to have only 2 fps but a higher picture quality. That's why I think these optional settings of framerate/quality would be useful to enable existing (older) equipment for NDI and send iVGA to legacy without worries...

Best regards,
Matthias

Hi Matthias.

There is no 'quality' setting in NDI, so the differences between your old and new laptops with NDI is curious. There are 2 possibilities that I can see.

1) The laptops are using different screen resolutions or window sizes and you are seeing a variation in scaling artifacts.
2) Is it possible the test with the older laptop had the 'Low Bandwidth' option checked in TriCaster ? That would certainly account for the different image you saw.

matthias-web
03-29-2016, 01:25 PM
1) The laptops are using different screen resolutions or window sizes and you are seeing a variation in scaling artifacts.
2) Is it possible the test with the older laptop had the 'Low Bandwidth' option checked in TriCaster ? That would certainly account for the different image you saw.

ad 1) Same screen resolution: Full HD 1920x1080
ad 2) No "low bandwith" option checked. The tests had been done right after each other with the same network.

As well the old laptop does not play NDI video properly, it seems to jump one or two times per second.
As said, if I could increase quality with decreasing framerate - as an option ina future version of scan converter - I would be happy for this scenario of transmitting text/information...

Best regards,
Matthias

livepad
03-30-2016, 05:44 AM
ad 1) Same screen resolution: Full HD 1920x1080
ad 2) No "low bandwith" option checked. The tests had been done right after each other with the same network.

As well the old laptop does not play NDI video properly, it seems to jump one or two times per second.
As said, if I could increase quality with decreasing framerate - as an option ina future version of scan converter - I would be happy for this scenario of transmitting text/information...

Best regards,
Matthias

So, we would expect dropped frames in NDI if the computer is too slow, but in theory the quality of individual frames should be the same on both systems.
Are they running different operating systems ?

matthias-web
04-02-2016, 01:47 AM
Are they running different operating systems ?
Same operating systems: Windows 10

Running the NDI test pattern tool by the way gives good results for both old and new laptop - even with the fine line test pattern.
So I think it is not a matter of NDI in general but specifically about the scan converter software.

See as well this message: http://forums.newtek.com/showthread.php?150378-Very-Blurry-NDI-Scan-Converter-Captures

Best regards,
Matthias

livepad
04-02-2016, 04:47 AM
Same operating systems: Windows 10

Running the NDI test pattern tool by the way gives good results for both old and new laptop - even with the fine line test pattern.
So I think it is not a matter of NDI in general but specifically about the scan converter software.

See as well this message: http://forums.newtek.com/showthread.php?150378-Very-Blurry-NDI-Scan-Converter-Captures

Best regards,
Matthias


Could you double check if your new laptop uses HiDPI ? This could be affecting things.

GeekNews
04-02-2016, 09:22 AM
I am running into the same issue very poor focusing / blurry images when for example a web page is displayed.

Todd

133216

kanep
04-02-2016, 04:45 PM
It might help to get more information. What kind of network connection? What graphics card?

Here are some sample from what I'm seeing, images grabbed from TC-Mini (4-0-160323) in a 1080p29.97 session. In all cases the Chrome window will full screen (minus the task bar).

Laptop 1 (high end)
i7 CPU, nVidia 950 CPU, built in GigE NIC, Windows 10 64-bit (Release build)
1920x1080
133228

1680x1050
133227


Laptop 2 (low end)
Celeron CPU, Intel HD GPU, USB3 to GigE NIC, Windows 10 64-bit (Insider Preview)
1366x768
133226

GeekNews
04-02-2016, 06:35 PM
Dell
Precision T3610
Intel Xeon E5-1620 @3.7ghz
Nvidia Quadro K4000
1680x1050
1GB Network
Windows 10

Firefox

Have been unable to get Chrome to be recognized yet.

matthias-web
04-03-2016, 12:00 AM
The laptop producing low, blurry quality with NDI Scan converter:

Sony Vaio Duo 11,
Intel i3-3217U CPU @ 1.80 GHZ
RAM 4.00 GB
Windows 10 home, 64 bit
Intel HD Graphics 4000
1920x1080 resolution

Gigabit Network

As written before, iVGA is delivering good quality from same laptop...

ACross
04-07-2016, 07:57 AM
There are a number of different threads here that actually have different probably causes, so I will try to cover a few things as best I can with the information that I have.

- "Have been unable to get Chrome to be recognized yet."
It is not quite clear to me what recognized means. If you mean that the application itself is not seen by Scan Converter, make Chrome active (i.e. click on it) then wait a few seconds and Scan Converter will have it on it's list. Scan Converter only lists applications that you have actually used so that the list of applications does not get all sorts of Windows utilities and hidden applications that windows tends to have always running these days. If the problem is that Chrome does not get captured correctly, the cause of this is almost certainly that you have two discrete GPUs in the system (e.g. an nVidia one and an Intel one) that are both enabled, there is a bug in Chrome/Windows that causes this which is why there is a warning when you launch the Scan Converter.

- "Low quality video"
My strong suspicion here is that the problem is not the sending of the video, but the viewing of it. In most cases I would expect NDI to have much higher quality video than iVGA ever did. If you are using AE2, I'd recommend clicking the grab icon by the on screen ISO window and looking at how that looks since this will capture the stream exactly 1:1 as it is sent. Please send me an email if it that looks blurred.

Koinonia
04-08-2016, 09:07 AM
I just updated the scan converter to 1.5 version and now when I try to open it I get the error message "Application.Network.ScanConverter.x64.exe has stopped working". One laptop has Windows Vista and the other one has Windows 7. All others NDI apps are working well.
133340

SBowie
04-08-2016, 09:46 AM
I've asked QA to try to replicate this issue. I take it it's failing on both systems, not just the Vista one?

Koinonia
04-08-2016, 10:07 AM
Hi Steve,

Windows 7 is working well, sorry if it wasn't clear. The issue is only with Windows Vista Ultimate 64bits. Scan Converter version 1 was working well.


I've asked QA to try to replicate this issue. I take it it's failing on both systems, not just the Vista one?

matthias-web
04-08-2016, 03:55 PM
- "Low quality video"
My strong suspicion here is that the problem is not the sending of the video, but the viewing of it. In most cases I would expect NDI to have much higher quality video than iVGA ever did. If you are using AE2, I'd recommend clicking the grab icon by the on screen ISO window and looking at how that looks since this will capture the stream exactly 1:1 as it is sent. Please send me an email if it that looks blurred.

The file I uploaded in my first answer was a compilation from these Tricaster grabs: http://forums.newtek.com/attachment.php?attachmentid=133119&d=1458980907

Here an other example, same network, just two laptops connected:

Laptop A:
Sony Vaio Duo 11, Intel i3-3217U CPU @ 1.80 GHZ, RAM 4.00 GB, Windows 10 home, 64 bit
Intel HD Graphics 4000, 1920x1080 resolution

Laptop B:
Samsung ATIV 880Z5E-X019, Intel i73635QM CPU @ 2.40 GHZ, RAM 16.00 GB, Windows 10 Pro, 64 bit
Intel HD Graphics 4000 and AMD Radeon HD 8800M, 1920x1080 resolution

NDI Scan converter 1.5 and NDI video monitor used on both laptops

Please see the difference:
Chrome window transmitted via NDI scan converter on laptop B, viewed via NDI video monitor on laptop A:
133342

Chrome window transmitted via NDI scan converter on laptop A, viewed via NDI video monitor on laptop B:
133344

If you have any idea what I can do/change to track the reason for this different quality, please let me know...
Many thanks for help!

matthias-web
04-08-2016, 04:35 PM
Ok, here is the solution.

First: Apologies to NDI scan converter!
You work fine even from older and weaker laptops!

I have fallen into a typical "cum hoc, ergo propter hoc" fallacy:
Yes, above mentioned Vaio is older, it is weaker... and it has only a 11" display with Full HD resolution. Therefore the windows display settings had been set to 125% - and exactly this created the blurry NDI transmission.
With 100% all is fine.

So if you have the same problem simply change the text and app size in the "windows display settings" to 100% on your sending computer:
133345
Right mouse click on desktop -> Display settings
Important: After changing, sign off or restart your laptop - otherwise change will not be taken for NDI scan...

All is fine. I am happy now and don't need to buy a bunch of new laptops for NDI. Bye, bye iVGA! :-)

VideoEng QA
04-08-2016, 05:00 PM
Hi Steve,

Windows 7 is working well, sorry if it wasn't clear. The issue is only with Windows Vista Ultimate 64bits. Scan Converter version 1 was working well.

We discovered an AVX dependency which is most likely causing this problem on your Windows Vista system. We should have a new build of NDI Tools uploaded later tonight that will correct the dependency. I apologize for any complications this issue has created.

Koinonia
04-11-2016, 07:25 AM
We discovered an AVX dependency which is most likely causing this problem on your Windows Vista system. We should have a new build of NDI Tools uploaded later tonight that will correct the dependency. I apologize for any complications this issue has created.

ThankYou for your prompt response and support! it's now working very well.

chippy
07-18-2017, 07:41 AM
Ok, here is the solution.

...

So if you have the same problem simply change the text and app size in the "windows display settings" to 100% on your sending computer:
133345
Right mouse click on desktop -> Display settings
Important: After changing, sign off or restart your laptop - otherwise change will not be taken for NDI scan...

All is fine. I am happy now and don't need to buy a bunch of new laptops for NDI. Bye, bye iVGA! :-)

Just registered to say thanks for the tip. All working now after an hour of frustration!

@Chippy