vMix Forums
»
General
»
NDI
»
NDI giving lots of compression artifacts, low quality, 140+Mbs.
Rank: Member
Groups: Registered
Joined: 4/22/2017(UTC)
Posts: 23
Location: WPG
Was thanked: 4 time(s) in 2 post(s)
|
I have attached two images to help explain the results I am seeing, on the NDI image, look in the top left corner for the most pronounced areas. Source and NDI should be the names, and in the source image you can see it is very clear and the divide between contrasting colors is smooth. On the NDI image, it has lots of compression artifacts and looks like the image is comprised of a bunch of small squares. I am using 3 computers, one connected over HDMI to another with a capture card and that shows perfect quality, and then it is connected to the third computer using NDI to do the final encoding out to the stream. It is a 1920x1080, 60 frames per second stream, and it shows around 140Mbs network usage. Also I have tested this going from all of the computers and they all show the same results. Even viewing the NDI source on the same computer with the NDI monitor shows this look. Is NDI just not suitable for this quality or am I doing something else wrong? File Attachment(s):  Source Capture (2).png (3,769kb) downloaded 57 time(s). NDI.png (2,940kb) downloaded 54 time(s).You cannot view/download attachments. Try to login or register.
|
|
|
|
|
|
Rank: Advanced Member
Groups: Registered
Joined: 8/2/2013(UTC) Posts: 1,072   Location: Fairhope, Alabama USA Thanks: 553 times
Was thanked: 200 time(s) in 166 post(s)
|
Have you tested other resolutions/frame rates? That will help you determine where the issue is.
- Tom
|
|
|
|
|
|
Rank: Member
Groups: Registered
Joined: 4/22/2017(UTC)
Posts: 23
Location: WPG
Was thanked: 4 time(s) in 2 post(s)
|
Hey Tom, yeah I have tried 1080/30 and 720/60 as well. Also both Intel and AMD systems and NVidia and AMD gpus. sinc747 wrote:Have you tested other resolutions/frame rates? That will help you determine where the issue is.
- Tom
|
|
|
|
|
|
Rank: Advanced Member
Groups: Registered
Joined: 8/2/2013(UTC) Posts: 1,072 Location: Fairhope, Alabama USA Thanks: 553 times
Was thanked: 200 time(s) in 166 post(s)
|
NDI is mostly CPU. In fact, possibly may make no use of the GPU at all.
Surprising that lower resolution/frame rate has no effect.
- Tom
|
|
|
|
|
|
Rank: Member
Groups: Registered
Joined: 4/22/2017(UTC)
Posts: 23
Location: WPG
Was thanked: 4 time(s) in 2 post(s)
|
Yeah, I'm using 6700k, 4930k and 1700x Ryzen, and ndi doesn't really put a load on them CPU wise. The NDI desktop capture has a GPU acceleration tab on it, so I just assumed there was some GPU usage too, but you are probably right. I've tried just the Intel CPUs too to. Ake sure it wasn't a Ryzen bug. sinc747 wrote:NDI is mostly CPU. In fact, possibly may make no use of the GPU at all.
Surprising that lower resolution/frame rate has no effect.
- Tom
|
|
|
|
|
|
Rank: Advanced Member
Groups: Registered
Joined: 2/27/2017(UTC)
Posts: 51
Location: NW Ohio
Thanks: 3 times
Was thanked: 13 time(s) in 4 post(s)
|
Have you tested with the free NDI monitor app from Newtek?
|
|
|
|
|
|
Rank: Member
Groups: Registered
Joined: 4/22/2017(UTC)
Posts: 23
Location: WPG
Was thanked: 4 time(s) in 2 post(s)
|
Yes, I've tried vMix, NDI Monitor, ISO recorder and Xsplit. I've used them in different ways too like using xsplit to send the NDI feed and such. kricher1964 wrote:Have you tested with the free NDI monitor app from Newtek?
|
|
|
|
|
|
Rank: Advanced Member
Groups: Registered
Joined: 5/20/2015(UTC) Posts: 493  Location: Copenhagen, Denmark Thanks: 389 times
Was thanked: 100 time(s) in 79 post(s)
|
Are you sure that both PCs have Gigabit ethernet interfaces, and the switcher is also Gigabit? :-)
|
|
|
|
|
|
Rank: Member
Groups: Registered
Joined: 4/22/2017(UTC)
Posts: 23
Location: WPG
Was thanked: 4 time(s) in 2 post(s)
|
Yep, and speeds seem good on both ends, also sending a RTMP stream results in perfect quality footage but it is much harder on the CPU and I might as well just be sending out to twitch from there. Maybe it just isn't meant to transfer perfectly? stigaard wrote:Are you sure that both PCs have Gigabit ethernet interfaces, and the switcher is also Gigabit? :-)
|
|
|
|
|
|
Rank: Advanced Member
Groups: Registered
Joined: 3/24/2016(UTC)
Posts: 331
Location: Chicago, IL
Was thanked: 143 time(s) in 94 post(s)
|
Are you using XSplit v2.9?
There is a bug in their software which is causing the compression issues when using NDI. I worked with the XSplit developers on this issue and they fixed it in a beta of 3.0. I've not tried the public release version, but try it see if it improves things.
Kane Peterson
NewTek
|
|
|
|
|
|
Rank: Member
Groups: Registered
Joined: 4/22/2017(UTC)
Posts: 23
Location: WPG
Was thanked: 4 time(s) in 2 post(s)
|
The xSplit is the newest version, 3.0 and I have used vMix to vMix, vMix to NDI Monitor, vMix to xSplit and more. I have tried 4 different computers as well, I think I might just be expecting too much from NDI as far as quality is concerned. There are a lot of contrasting colors. kane wrote:Are you using XSplit v2.9?
There is a bug in their software which is causing the compression issues when using NDI. I worked with the XSplit developers on this issue and they fixed it in a beta of 3.0. I've not tried the public release version, but try it see if it improves things.
Kane Peterson
NewTek
|
|
|
|
|
|
Rank: Advanced Member
Groups: Registered
Joined: 3/24/2016(UTC)
Posts: 331
Location: Chicago, IL
Was thanked: 143 time(s) in 94 post(s)
|
element wrote:The xSplit is the newest version, 3.0 and I have used vMix to vMix, vMix to NDI Monitor, vMix to xSplit and more. I have tried 4 different computers as well, I think I might just be expecting too much from NDI as far as quality is concerned. There are a lot of contrasting colors. kane wrote:Are you using XSplit v2.9?
There is a bug in their software which is causing the compression issues when using NDI. I worked with the XSplit developers on this issue and they fixed it in a beta of 3.0. I've not tried the public release version, but try it see if it improves things.
Kane Peterson
NewTek I'd also give the vMix Desktop Capture tool a try or there is now a NDI plug-in for OBS. https://obsproject.com/f...ugin-for-obs-studio.528/NDI is able to handle this, but it all starts with the source capture application. Kane Peterson NewTek
|
|
|
|
|
|
Rank: Advanced Member
Groups: Registered
Joined: 3/28/2016(UTC) Posts: 159 Location: SACRAMENTO Thanks: 5 times
Was thanked: 19 time(s) in 18 post(s)
|
element wrote:I have attached two images to help explain the results I am seeing, on the NDI image, look in the top left corner for the most pronounced areas.
Source and NDI should be the names, and in the source image you can see it is very clear and the divide between contrasting colors is smooth. On the NDI image, it has lots of compression artifacts and looks like the image is comprised of a bunch of small squares.
I am using 3 computers, one connected over HDMI to another with a capture card and that shows perfect quality, and then it is connected to the third computer using NDI to do the final encoding out to the stream.
It is a 1920x1080, 60 frames per second stream, and it shows around 140Mbs network usage. Also I have tested this going from all of the computers and they all show the same results. Even viewing the NDI source on the same computer with the NDI monitor shows this look.
Is NDI just not suitable for this quality or am I doing something else wrong? I have found that NDI isn't always the best option when doing eSport high fps type of games. In my lab i was able to use a 10Gbp pure network on two 4proc machines which was good but in no ways realistic and production worthy (in regards to cost for doing an acual event) so i have left NDI to less busy shots such as player cams and crowd cams unless i'm doing slower action games. NDI seems to be a great a solution for most but not all. I've been sticking with SDI for actual game captures. I've had issues with sound over NDI as well. Then again I've only used vMix so it could have nothing to do with NDI. Whats funny is how its said NDI is so cpu intensive yet i don't see it using much of CPU but bandwidth yes. I will soon be really pushing the specs of NDI seeing if it's a configuration issue with the network but i was using DELL PC 7048's and the 10Gb optical modules that were originally configured for an old iSCSI SAN so by no means an optimized solution but figured good enough being I've pushed 1.2GB a sec over that network for almost 1 years continuously with no dropped frames
|
|
|
|
|
|
Rank: Advanced Member
Groups: Registered
Joined: 5/13/2014(UTC) Posts: 518  Location: Manchester, UK Thanks: 2 times
Was thanked: 183 time(s) in 130 post(s)
|
NDI at 1920x1080 60fps can consume a lot of bandwidth, much more than 140Mb/s for a highly complex moving image, and the codec, whilst good, is not "unbreakable" in terms of image quality & artefacts. I've just done a few tests at 1080p60 with my NDI Signal Generator, which was originally created to generate high bitrate NDI streams in order to test LAN+NDI application configurations and detect frame drops across a complex signal path. I've attached three image segments from the NDI Monitor & Task Manager, showing network usage and part of the test signal. 1) This is a moderately complex but mainly static image (apart from a barcode strip across the bottom of frame), but it's using ~250Mb/s and there is some visible degradation to the ZEN image. 2) This is a more complex moving pattern + barcode, apart from the ZEN image which remains static, and uses ~330Mb/s, producing visible degradation. 3) This is a much simpler static image, largely black plus the "Indian Head" test pattern and moving barcode, but even this uses ~150Mb/s, although the ZEN image is clean compared to the previous two images. zenvideo attached the following image(s): 1080p60-1.PNG (245kb) downloaded 24 time(s). 1080p60-2.PNG (289kb) downloaded 26 time(s). 1080p60-3.PNG (364kb) downloaded 29 time(s).You cannot view/download attachments. Try to login or register.
|
|
|
|
|
|
vMix Forums
»
General
»
NDI
»
NDI giving lots of compression artifacts, low quality, 140+Mbs.
Forum Jump
You cannot post new topics in this forum.
You cannot reply to topics in this forum.
You cannot delete your posts in this forum.
You cannot edit your posts in this forum.
You cannot create polls in this forum.
You cannot vote in polls in this forum.
Important Information:
The vMix Forums uses cookies. By continuing to browse this site, you are agreeing to our use of cookies.
More Details
Close
