Kodi 16.1 - Nvidia GPU used with DXVA; uncertain which deinterlace mode is being used
#1
Hey guys, I'm using Kodi 16.1 because it seems that DVD standard PCM audio in VOB files is broken in 17 and 18 from my testing. At any rate, I'm noticing a *bit* of jitter on my H.264 1080i videos that would imply bob deinterlacing is being used instead of Adaptive, but I can't seem to figure out where to tell what method is being used. Note that I've set the render method to DXVA and deinterlace is set to Auto, but the deinterlace *method* is greyed out as Auto. I would historically always set this to DXVA Best in past versions.

I can also see from the logs that the supported methods for this Nvidia GPU are Blend, Bob, and Adaptive. Nowhere in the log shows which method is actually used. Anyone know where to get this info?
Reply
#2
Anyone have any idea? I realize that the internet seemingly has moved on from interlaced content, but almost the entire history of broadcast TV is interlaced, so it's pretty important to me Smile
Reply
#3
Developer support for Kodi 16.1 is water under under the bridge, although the mods in the forum will help with what tools are available.

I'm quite aware of the history of interlace displays coming from an Amiga background that had to deal with flicker fixers and scan doublers to tolerate high res on a monitor. de-intelacing can come from the software in Kodi or software in your graphic card (if you have hardware acceleration set on in the gfx card, then it's done in chip. The primary source of this information is going to be with your graphic card manufacturer and you would have to get terribly lucky to talk to someone knowledgeable enough to discus 'a *bit* of jitter' and might just be  a bit of a reach. One reader on the Nvidia site suggest to keep interlacing off, and instead use post processing whihc reduces pixellation/macroblocking on low-res/low-bitrate videos making them look slightly better.

Video playback (wiki) Deinterlace method = The methods available here are hardware dependant and the wiki outlines the video methods. Some suggestion is that bob will introduce fine lines and tend to judder/shimmer.

There was some Kodi discussion a long while ago (the forum is huge, Google is your friend).

Suggestion: Install the current Kodi in portable mode, it will function completely independent from your present set-up and you'll have a new daily driver (crossing your fingers for the fix) then when you make a bug track, developers are going to be all ears.
Reply
#4
(2020-07-02, 01:41)PatK Wrote: Developer support for Kodi 16.1 is water under under the bridge, although the mods in the forum will help with what tools are available.

I'm quite aware of the history of interlace displays coming from an Amiga background that had to deal with flicker fixers and scan doublers to tolerate high res on a monitor. de-intelacing can come from the software in Kodi or software in your graphic card (if you have hardware acceleration set on in the gfx card, then it's done in chip. The primary source of this information is going to be with your graphic card manufacturer and you would have to get terribly lucky to talk to someone knowledgeable enough to discus 'a *bit* of jitter' and might just be  a bit of a reach. One reader on the Nvidia site suggest to keep interlacing off, and instead use post processing whihc reduces pixellation/macroblocking on low-res/low-bitrate videos making them look slightly better.

Video playback (wiki) Deinterlace method = The methods available here are hardware dependant and the wiki outlines the video methods. Some suggestion is that bob will introduce fine lines and tend to judder/shimmer.

There was some Kodi discussion a long while ago (the forum is huge, Google is your friend).

Suggestion: Install the current Kodi in portable mode, it will function completely independent from your present set-up and you'll have a new daily driver (crossing your fingers for the fix) then when you make a bug track, developers are going to be all ears.

I do appreciate your help and these are reasonable suggestions. Having said that, I do know quite a bit about interlacing, as I worked in the software world designing DVD and Blu-ray compliant output streams via FFMPEG (and for our particular software 1080i was always preferable to 1080p24 or 720p60). My question is really just how do I tell what interlacing mode is being used in this particular scenario (Nvidia 860m, DXVA, Win 7). Once I find that out, I can troubleshoot further.

As for the bug I mentioned, I do plan on reporting this, but I first plan on creating a video from scratch from FFMPEG using SMPTE bars and generated sound. This will help me (and more importantly the developers) figure out the scope, whether it is actually the PCM audio itself, the VOB container, or perhaps the way the VOB data is written. Essentially, I need time to do my end of the testing so that it is isolated to the point where I know it doesn't require a lot of searching and head scratching on the part of developers.
Reply
#5
(2020-07-02, 02:53)alexpigment Wrote: My question is really just how do I tell what interlacing mode is being used in this particular scenario (Nvidia 860m, DXVA, Win 7). Once I find that out, I can troubleshoot further.

Use Player Process Info which is displayed using O key, see https://kodi.wiki/view/Video_playback#Pl...ocess_Info
Reply
#6
I can definitely bring up the process info via the O key, but it doesn't show anything about deinterlacing from what I can tell. It says "dc:ff-mpeg2video-dxva2", but I don't think that implies anything about deinterlacing - just that it's using DXVA2 for decoding. What I'm seeing looks like the first screenshot on this page (although the particulars are different obviously):

https://kodi.wiki/view/Codecinfo

Any other suggestions are welcome. Thanks!
Reply
#7
Just wanted to update this thread. I was able to 'fix' this by installing Kodi 15. Now I can select "DXVA - Best" and there's no more jitter on interlaced material. Not sure what all features I'm missing between 15 and 18, but I can at least say that all my videos are working properly Smile
Reply
#8
(2020-07-25, 22:04)alexpigment Wrote: by installing Kodi 15
Forget what I said about water under the bridge... 15 is down river, mired in a sandbank! Glad it worked out for you, there is always the option to run an external video player should the latest features attract, and you find a player that responds to your needs.
Reply
#9
(2020-07-25, 22:04)alexpigment Wrote: Just wanted to update this thread. I was able to 'fix' this by installing Kodi 15. Now I can select "DXVA - Best" and there's no more jitter on interlaced material. Not sure what all features I'm missing between 15 and 18, but I can at least say that all my videos are working properly

Although I can perfectly understand why you would do this, it isn't a 'fix' that helps anyone but you.  As a team, we'd rather that we could fix the issue going forwards (not backwards) and roll that out to everyone by understanding what has changed.  If you're happy to stick with an old version because "this bit works" then that's fine but be aware that the team won't help support any issues with that.  It also doesn't help us progress. Things are changed for a reason.  Usually, the reason is clear and lots of testing is done but sometimes things get accidentally broken.

I'm not saying that this is the case here because I honestly don't know,  but I do know that as a team, we would prefer to fix things going forward rather than have users revert to older versions.  debug log (wiki)'s from a working and a not-working version would be a good start.  However, devs work on stuff that interests them.  We all do this for free and in our spare time so some fixes come quicker than others and some don't come at all! 

From your comments you seem pretty clued-up about the video aspect so maybe you could help debug this and find a better solution than using v15 Huh
Learning Linux the hard way !!
Reply
#10
(2020-07-27, 00:15)black_eagle Wrote:
(2020-07-25, 22:04)alexpigment Wrote: Just wanted to update this thread. I was able to 'fix' this by installing Kodi 15. Now I can select "DXVA - Best" and there's no more jitter on interlaced material. Not sure what all features I'm missing between 15 and 18, but I can at least say that all my videos are working properly

Although I can perfectly understand why you would do this, it isn't a 'fix' that helps anyone but you.  As a team, we'd rather that we could fix the issue going forwards (not backwards) and roll that out to everyone by understanding what has changed.  If you're happy to stick with an old version because "this bit works" then that's fine but be aware that the team won't help support any issues with that.  It also doesn't help us progress. Things are changed for a reason.  Usually, the reason is clear and lots of testing is done but sometimes things get accidentally broken.

I'm not saying that this is the case here because I honestly don't know,  but I do know that as a team, we would prefer to fix things going forward rather than have users revert to older versions.  debug log (wiki)'s from a working and a not-working version would be a good start.  However, devs work on stuff that interests them.  We all do this for free and in our spare time so some fixes come quicker than others and some don't come at all! 

From your comments you seem pretty clued-up about the video aspect so maybe you could help debug this and find a better solution than using v15 Huh

Sure, I completely understand it. I worked at a software company for almost 10 years, and it was always hard to support older versions for people who could not adequately describe why they went back to an earlier version. It also doesn't help the software progress. Totally get it.

I do plan on submitting a bug report for the issue where my VOB files with PCM audio don't have sound in the current version. I just need a little bit of time to figure out the details, like:
1) Is this specific to certain video files, or does it occur for any file with conditions A, B, & C present. To be clear, so many DVDs have PCM audio that I would assume it's a bit more specific than that, otherwise people would have been reporting it left and right.
2) Does this occur on one system or multiple.
3) Does the sound setup (e.g. HDMI audio to the TV, then optical audio to a receiver in my case) play a part.

I'm a bit short on time at the moment, but I do promise to get this done sometime soon. However, I do believe there is still value in knowing an old bug exists in one version and not another; you are almost certainly going to have people that can't use the newest version because of some reason, and you can't reasonably expect them to wait until a potentially niche bug gets fixed by a developer who works for free and cherrypicks the ones they want to tackle Wink
Reply
#11
@black_eagle Not to get too off topic here, but the original issue I was running into regarding VOB files with PCM audio not having sound in Kodi 17 and onward is almost certainly an issue with FFMPEG. I can see that in FFMPEG 3.0.1, the audio channel is seen as pcm_dvd, but in FFMPEG 3.1.4, the audio is seen as "mlp, 0 channels" and is effectively thrown away. This issue was fixed between FFMPEG 4.2.3 and 4.3. So ultimately, I think this issue will be fixed once Kodi integrates something newer than FFMPEG 4.2.3. If you have a timeline for when this might happen, please let me know. Thanks!
Reply
#12
Update to my last update: I figured if it's now fixed in FFMPEG, it might be fixed in the Kodi nightlies for Matrix. I just checked the July 29th nightly and it is indeed fixed there. I guess I should look forward to the Matrix release for a version of Kodi that works for my purposes.
Reply
#13
Its already done in V19 Alpha 1, and v19 nightlies since 23rd June https://github.com/xbmc/xbmc/pull/18071 and the 4.3.1 update https://github.com/xbmc/xbmc/pull/18166
Reply

Logout Mark Read Team Forum Stats Members Help
Kodi 16.1 - Nvidia GPU used with DXVA; uncertain which deinterlace mode is being used0