LAV CUVID Decoder - High Quality Hardware decoding for NVIDIA

[Tom Keller]

Using MPC-HC 1.5.2.3018 with a couple of 1080p H.264 clips @23.976fps (on WinXP SP3; C2D E6600 @2,4Ghz; 9600GT with driver version 267.24) i always experience some very high cpu consumption here (around 50-55%) with almost every video renderer... except madVR . I counter checked with GraphStudio - same there.

So using VMR9 or EVR with the LAV CUVID Decoder simply gives me a higher cpu load, than pure software decoding ... and therefore occasional stuttering. The only exception is madVR as video renderer - this lowers my cpu consumption to a total of 13-17% playing the same files.

Any suggestions on what may be the reason of this behavior?

[roozhou]

Originally Posted by Tom Keller

Using MPC-HC 1.5.2.3018 with a couple of 1080p H.264 clips @23.976fps (on WinXP SP3; C2D E6600 @2,4Ghz; 9600GT with driver version 267.24) i always experience some very high cpu consumption here (around 50-55%) with almost every video renderer... except madVR . I counter checked with GraphStudio - same there.

So using VMR9 or EVR with the LAV CUVID Decoder simply gives me a higher cpu load, than pure software decoding ... and therefore occasional stuttering. The only exception is madVR as video renderer - this lowers my cpu consumption to a total of 13-17% playing the same files.

Any suggestions on what may be the reason of this behavior?

Did you tried overlay mixer? This has the least cpu and GPU comsumption under WinXP.

[Tom Keller]

I did. Always the same: 50-55% cpu load, occasional stuttering and a bit of a laggy mouse cursor while playing. But no problem using madVR.


EDIT: I assume the problem is in some kind related to the NV12 colorspace, since CoreAVC behaves the same, when setting NV12 as only output format . CoreAVC doing fine though, using its internal colorspace conversion.
So when using LAV CUVID Decoder plus ffdshow for colorspace conversion there are no problems (with around 20-30% cpu load).

I guess i'll have to wait, till the LAV CUVID Decoder supports colorspace conversion itself and therefore different output formats. Or (maybe) a different graphics driver helps(?)...

EDIT 2: Tried GeForce driver versions 267.91 & 270.51 - no change at all .

[Carpo]

only thing stoping me from using this decoder is the fact that it using it and madvr means i dont get any subtitles, other than that, they are a winning team

[sneaker_ger]

Originally Posted by Carpo

only thing stoping me from using this decoder is the fact that it using it and madvr means i dont get any subtitles, other than that, they are a winning team

This is not the fault of LAV CUVID but most likely a misconfiguration on your side.

[SamuriHL]

Yea, I use it with madVR and the latest MPC-HC and I get subs. They work great for me.

[Carpo]

Yes, some how auto load subtitles was unticked, which is strange because i cant remember unticking it, and shouldn't be unticked on a fresh install of MPC-HC :/

[pankov]

nev,
I've just changed my video card from ATI 5750 to NVidia GTX 460 SE so I can use your decoder, cause I need hardware deinterlacing and often subtitles at the same time which is not possible with any other decoder out there but I'm sad to report that it's not working as I expected.
If you try the following sample
http://www.mediafire.com/?em2ouktaqfvd36f
(the same BBC-HD sample from the World Cup - Argentina vs. Nigeria that crashes VSFilter)
with MS DTV-DVD Video decoder and EVR you'll see perfect fluid motion.
With LAV CUVID decoder it's somewhat strange - if I pause the video I get the same picture, so it's not Bob-ed but it's not Vector Adaptive that I get with MS' decoder. .... or it could be that the frames are not sent to the deinterlacer in the correct order. I'm just guessing here but I hope you have some control over this and you can fix it.
Just to say that the problem is not only with this sample but with others that don't have subtitles or simply use a splitter (like Haali's) that doesn't expose the embedded DVB subtitles.

[nevcairiel]

Well one difference is that when decoding it normally and letting EVR do the deinterlacing, you will actually get 50fps to the renderer, while when the decoder does it, it gets reduced to 25fps (no frame doubling). I don't know if/how i can influence that behaviour though..

[pankov]

I see now that you are absolutely right but I hope you'll be able to find a solution to output all 50/60 deinterlaced frames.
Till then can you, please, add an option to output the interlaced frames/fields and set the appropriate interlaced flag so we can use the hardware deinterlacer in the renderer?

[madshi]

Originally Posted by nevcairiel

Well one difference is that when decoding it normally and letting EVR do the deinterlacing, you will actually get 50fps to the renderer, while when the decoder does it, it gets reduced to 25fps (no frame doubling). I don't know if/how i can influence that behaviour though..

Interesting. So what does that mean for IVTC? I guess LAV CUVID outputs 30p for NTSC/ATSC interlaced movie content?

[pankov]

Nev,
I think I've found a problem when using LAV CUVID and subtitles. To be precise LAV CUVID + DirectVobSub.
From my tests I noticed that these two don't work at all and sadly that's the only way to show subtitles in ZoomPlayer.
I think I've also found the reason but I'll be happy if you confirm and probably fix it in the future. From your posts I understand that currently LAV CUVID supports NV12 output while DirectVobSub doesn't support it at all. It still supports YV12 and from madshi's posts in the madVR thread I understood that these two formats are almost the same - there is a quick and lossless transformation between them.
So my question is "do you plan to add YV12 support to your decoder?" ... or NV12 support to VobSub if it's easier ... or I better ask the MPC developers for the last one?

[nevcairiel]

The hardware decoder always outputs NV12, and i currently have no plans to write code to convert it into anything else, sorry.

[italospain]

Originally Posted by pankov

nev,
I've just changed my video card from ATI 5750 to NVidia GTX 460 SE so I can use your decoder, cause I need hardware deinterlacing and often subtitles at the same time which is not possible with any other decoder out there but I'm sad to report that it's not working as I expected.
If you try the following sample
http://www.mediafire.com/?em2ouktaqfvd36f
(the same BBC-HD sample from the World Cup - Argentina vs. Nigeria that crashes VSFilter)
with MS DTV-DVD Video decoder and EVR you'll see perfect fluid motion.
With LAV CUVID decoder it's somewhat strange - if I pause the video I get the same picture, so it's not Bob-ed but it's not Vector Adaptive that I get with MS' decoder. .... or it could be that the frames are not sent to the deinterlacer in the correct order. I'm just guessing here but I hope you have some control over this and you can fix it.
Just to say that the problem is not only with this sample but with others that don't have subtitles or simply use a splitter (like Haali's) that doesn't expose the embedded DVB subtitles.

There is no problem to get Subtitles with Hardware Deinterlacing with Zoom Player at least with ATI Cards.

I use ffdshow raw filter after CoreAVC (output set to Y12) to aktivate NV12 BOB and subtitles. It fixes CoreAVC wrong field order too.
I do the same with DScaler IVTC Mod for mpeg2 (doesnt support NV12) but this way i get hardware deinterlacing and subtitles.

[pankov]

I guess I should read better next time before deciding on changing hardware just on hunches that it will solve all my problems.
At the moment both my dreams (VA deinterlacing with madVR and VA deinterlacing + subtitles) are unfulfilled
but nevertheless thanks for all your hard work

[pankov]

italospain,
are you saying that you get the great quality of the Vector Adaptive deinterlacing that we get with the MS decoder?
I simply can't imagine how it's possible for ffdshow to add subtitles to an interlaced video stream and still keep it unmolested and send it to the renderer. btw which renderer are you using?
can you, please, post (or if it's better to send them as PM - to not pollute this thread) some screenshots of your ffdshow settings?

[italospain]

Originally Posted by pankov

italospain,
are you saying that you get the great quality of the Vector Adaptive deinterlacing that we get with the MS decoder?
I simply can't imagine how it's possible for ffdshow to add subtitles to an interlaced video stream and still keep it unmolested and send it to the renderer. btw which renderer are you using?
can you, please, post (or if it's better to send them as PM - to not pollute this thread) some screenshots of your ffdshow settings?

yeah i get vector adaptive deinterlacing.

there are no special ffdshow settings only nv12 and bob and subtitles

I have made a ffdshow Profile for interlaced material (*.mkv-i in ffdshow Profiles) together with Smart play Profile of Zoom player (use EVR & ffdshow raw filter(NV12 BOB Subtitles) only for interlaced material otherwise madVR(YV12 Weave DirectVobSub))

if you dont want CoreAVC you can use ffdshow decoder the subtitles works fine with hardware deinterlacing.

oh and there is a bug in Zoom Player Version 6 the subtitles must be external to be shown by ffdshow (you can do it with MKVtoolnix)

sorry for the wrong thread

[italospain]

Originally Posted by madshi

Interesting. So what does that mean for IVTC? I guess LAV CUVID outputs 30p for NTSC/ATSC interlaced movie content?

for ATI Cards you can activate Hardware IVTC like Hardware Deinterlacing (NV12 & BOB & EVR)

[pankov]

yes,
but the question madshi aks is will the decoer (LAV CUVID) know that the framerate is change from 30 fps (29.940) to 24fps (23.976) and be able to tell it to renderer (madVR)

[roozhou]

Compared to deinterlace, IVTC is quite easier. IMO it is not very difficult to add an adaptive IVTC option to the renderer.