HOW TO: Purevideo Decoder Registry Patch

[csy]

This Purevideo decoder registry patch is a shortcut method for configuring the Purevideo video and audio decoders. This overcomes difficulties accessing the Purevideo configuration properties (particularily audio) and confusion arising from the Purevideo configuration properties not showing the currently configured settings and not necessarily showing all the available options. The Purevideo decoder will use these configuration settings on ALL applications, and can be manually edited from the Purevideo configuration or direct registry changes. If you are happy with configuring the Purevideo decoder via its own configuration properties, then there is no need for this patch.

Summary:
The principle aim of the registry settings below is to enable hardware de-interlacing to provide the best picture quality available on your system (quality is video card dependant), and enable DD/DTS 5.1 software decoding (if supported by your Purevideo decoder product type). In more detail, the registry patch enables hardware acceleration, enables VMR7/9 capability, enables hardware de-interlacing capability (video card dependant), no decoder aspect ratio correction (anamorphic/raw), and enables DD/DTS 5.1 software decoding with large speakers at front and small centre and rear speakers plus subwoofer, and full audio dynamic range.
Copy and paste the below code into notepad and save with a given filename, then change filename extension to .reg and double-click on file and you should be prompted to add the patch to the registry.

Caution: this should only be applied if your video card supports DXVA and VMR

Code:

REGEDIT4

[HKEY_LOCAL_MACHINE\SOFTWARE\NVIDIA Corporation\Filters\Video]
"DisplayType"=dword:00000003
"DeinterlaceControl"=dword:00000000
"EnableVMR"=dword:00000002
"VMRDeinterlace"=dword:00000040
"EnableDXVA"=dword:00000001
"DeinterlaceMode"=dword:00000000

[HKEY_LOCAL_MACHINE\SOFTWARE\NVIDIA Corporation\Filters\Audio]
"FrontSpeakerSize"=dword:00000000
"CenterSpeakerSize"=dword:00000001
"RearSpeakerSize"=dword:00000001
"SubwooferPresent"=dword:00000001
"ConnectedDevicePropControl"=dword:00000002
"EnableBassManagement"=dword:00000001
"MaxOutChannels"=dword:00000006
"AC3OutputMode"=dword:00000007
"AC3LfeOn"=dword:00000001
"SpdifPropControl"=dword:00000000
"EnableSPDIFPassThru"=dword:00000000
"AC3DynamicRangeLow"=dword:00000000
"AC3DynamicRangeHigh"=dword:00000000
"AC3CompressionMode"=dword:00000002

Options:
Display Type – Content Default (keep original aspect ratio): "DisplayType"=dword:00000000
Display Type – Letterbox (apply correct aspect ratio suitable for 16x9 display): "DisplayType"=dword:00000001
Display Type – Pan & Scan (apply correct aspect ratio suitable for 4x3 display): "DisplayType"=dword:00000002
Display Type – Anamorphic/raw (no aspect ratio): "DisplayType"=dword:00000003
Prefer Overlay (enable overlay, disable VMR): "EnableVMR"=dword:00000000
Prefer VMR7 (enable VMR7, disable overlay): "EnableVMR"=dword:00000001
Prefer VMR9 (enable VMR9, disable overlay): "EnableVMR"=dword:00000002
Hardware acceleration enabled: "EnableDXVA"=dword:00000001
Hardware acceleration disabled: "EnableDXVA"=dword:00000000
Automatic de-interlacing control: "DeinterlaceControl"=dword:00000000
Film (de-interlacing forced off) de-interlacing control: "DeinterlaceControl"=dword:00000001
Video (de-interlacing forced on) de-interlacing control: "DeinterlaceControl"=dword:00000002
Smart de-interlacing control (not used on 1.02-223): "DeinterlaceControl"=dword:00000003
Software Best Available (bob or weave) de-interlacing: "DeinterlaceMode"=dword:00000000
Software Display Fields Separately (bob) de-interlacing: "DeinterlaceMode"=dword:00000001
Software Combine Fields (no) de-interlacing: "DeinterlaceMode"=dword:00000002
Hardware VMR default (auto) de-interlacing: "DeinterlaceControl"=dword:00000000 "VMRDeinterlace"=dword:00000040
Hardware VMR Pixel Adaptive (can mean anything) de-interlacing: "DeinterlaceControl"=dword:00000005 "VMRDeinterlace"=dword:00000040
Hardware VMR Vertical Stretch (bob) de-interlacing: "DeinterlaceControl"=dword:00000005 "VMRDeinterlace"=dword:00000002
Analogue stereo (default): "MaxOutChannels"=dword:00000002
Analogue 6 (5.1) channel output: "MaxOutChannels"=dword:00000006
LFE output on its own (subwoofer) channel: "SubwooferPresent"=dword:00000001 "AC3LfeOn"=dword:00000001
LFE output redirected to large speakers ??? (no subwoofer): "SubwooferPresent"=dword:00000000 "AC3LfeOn"=dword:00000001
Large speakers (full freq range): "……SpeakerSize"=dword:00000000
Small speakers (120Hz low freq cutoff): "……SpeakerSize"=dword:00000001
SPDIF pass-through: "MaxOutChannels"=dword:00000002 "AC3OutputMode"=dword:00000002 "AC3LfeOn"=dword:00000000 "SpdifPropControl"=dword:00000001 "EnableSPDIFPassThru"=dword:00000001
Audio ‘Theatre’ Dynamic Range (full): "AC3DynamicRangeLow"=dword:00000000 "AC3DynamicRangeHigh"=dword:00000000 "AC3CompressionMode"=dword:00000002
Audio ‘Normal’ Dynamic Range (mild compression): "AC3DynamicRangeLow"=dword:00002710 "AC3DynamicRangeHigh"=dword:00002710 "AC3CompressionMode"=dword:00000002
Audio ‘Late Night’ Dynamic Range (high compression): "AC3DynamicRangeLow"=dword:00000000 "AC3DynamicRangeHigh"=dword:00000000 "AC3CompressionMode"=dword:00000003
Expose the hidden video configuration property tabs: "EnablePropPage"=dword:00000001 "PureVideoPropPage"=dword:00000001
Expose the hidden audio configuration property tabs: "EnablePropPage"=dword:00000001

Notes:
1. The video and audio sub-keys are separate and you can apply each sub-key independantly.
2. Hardware de-interlacing provides the best picture quality available on your system (quality is video card dependant), but is dependant on DXVA and VMR-rendering to achieve this, therefore GBPVR needs to be configured to use a VMR renderer (VMR9, VMR9-custom, VMR7) for this to work.
3. VMR is CPU intensive, therefore recommend 2GHz CPU or faster to ensure smooth playback on VMR
4. Due to a limitation in the way the Purevideo video decoder works, because the registry patch has enabled "Prefer VMR", it has disabled decoder support for overlay mode, meaning this decoder will not be used if GBPVR is configued to Overlay renderer (unless you change the patch to "Prefer Overlay", but that will disable hardware de-interlacing)
5. If video decoder aspect ratio correction is configured, GBPVR (v0.97.13) VMR9 and VMR7 renderers applies this decoder aspect ratio correction inside the GBPVR "F7" aspect ratio rectangle (VMR9-custom does not). This can accidentally cause double aspect ratio correction to VMR9 and VMR7 renderer if GBPVR is also applying an “F7” aspect ratio (particularly if using GBPVR ‘auto’ aspect ratio during LiveTV-timeshift or video playback)
6. DD/DTS software decode and SPDIF pass-though capability is limited to the product type capability. DD decode and SPDIF pass-through only works on the Gold and Platinum Purevideo products. DTS decode and SPDIF pass-through only works on the Platinum Purevideo product. In particular note the Bronze Purevideo product does not allow DD/DTS SPDIF pass-through.
7. SPDIF pass-through will transparently forward the AC3 signal within Directshow to the soundcard for processing. If the soundcard has inbuilt hardware DD/DTS decoder, then you can configure the soundcard driver to decode the DD/DTS or alternatively also transparently forward the AC3 signal to an external SPDIF interface on the soundcard. Note you should not have the DVD player external SPDIF cable connected otherwise you will end-up with dual AC3 signals presented to the soundcard when playing DVD’s in the drive. Note also that the Purevideo audio decoder is intelligent enough to know to automatically fall-back to software decoding when an AC3 signal is not present, eg MPEG2 video playback.
8. The Purevideo taskbar icon only appears if the Purevideo decoder is the default Directshow decoder (has the highest Directshow 'merit' value), and GBPVR config is set to use the default video and audio decoders, and the Purevideo decoder is currently in use (GBPVR actively doing video/DVD playback).
9. It is important to note the Purevideo decoder is an indepentant MPEG2 decoder with no dependancy on Nvidia video cards or Forceware drivers, and will work equally well on non-Nvidia video cards.
10. Nvidia video cards have a video post-processing (VPP) engine which provides edge sharpening and etc (same as ATI cards), however early Forceware drivers required the Purevideo decoder to enable the VPP engine and certain Purevideo hardware features on the video card. Nvidia has been removing the dependancy over recent Forceware driver releases, and IMO (but maybe wrong) the latest Forceware drivers have the VPP engine and all Purevideo hardware features fully enabled all the time without any dependancy on the Purevideo decoder.
11. The Purevideo trial activation key can only be used once. If you try re-using the key (even within the trial period), the application will install and configure ok, however the decoder Directshow output pin is disabled therefore Directshow will fall-back to using the default decoder.
12. If using the trial decoder and the trial period expires, the decoder Directshow output pin is disabled therefore Directshow will fall-back to using the default decoder.
13. If you are unhappy with what the registry patch has done, then you can overwrite the settings by simply going into the Purevideo decoder configuration properties and configure the decoder as desired. Alternatively you can default the configuration by launching Regedit (at command prompt type regedit), navigate to the decoder video and audio sub-keys and remove all the dwords within those sub-keys.

[gkar]

I'm confused. Is this only relevant if you are playing back DVD media files via speakers plugged into the motherboard? S/PDif has always worked for me perfectly, 5.1 & DTS.

The only extra requirement was to install AC3XForm.exe. I use Zoomplayer as my preferred player because of its configurability.

If so, it's just another reason to playback to a HT receiver.

I remember reading somewhere something about Dolby Inc. forcing Nvidia to cripple their audio decoder to third party players. But GB-PVR uses WMP as its default player so I don't why it should be affected.

[csy]

It all depends on your configuration.

If the AC3/DTS compressed audio stream is going via Directshow to your sound chipset (onboard motherboard or plugin soundcard) and the Directshow software decoder used is the Purevideo audio decoder, and you have configured it to SPDIF pass-through, then the Purevideo decoder will simply pass the AC3/DTS signal directly to the sound chipset without decoding it. The sound chipset can then decode the signal to separate analogue channels (if supported and configured) or can simply output the signal to an external SPDIF connector to be connected to an external audio decoder. Note the Purevideo audio decoder has inbult AC3XForm, so if the Purevideo audio decoder is being used in the Directshow graph, then the AC3XForm filter will not be used.

The problem I noticed is the Purevideo audio decoder Directshow output pin is not negotiating the AC3 tag with the Default Directshow audio renderer, and instead negotiating normal PCM channels. This seems to work for DD because I think the Purevideo decoder is still software decoding the DD signal, however whenever I try to play a DVD containing DTS, then there is no audio output. However if I configure GBPVR to use a different audio decoder (also with SPDIF pass-through configured), then all works. I have therefore come to the conclusion that SPDIF pass-through is not working correctly on the Purevideo audio decoder.

I note you are using Zoomplayer, so your AC3/DTS signal path will depend on how you have configured that application and what filters it is using in the directshow graph (it may not be using the Purevideo audio decoder at all). The fact that you had to install an AC3XForm filter implies you are not using the Purevideo audio decoder in Zoomplayer.

[gkar]

csy,

I note you are using Zoomplayer, so your AC3/DTS signal path will depend on how you have configured that application and what filters it is using in the directshow graph (it may not be using the Purevideo audio decoder at all). The fact that you had to install an AC3XForm filter implies you are not using the Purevideo audio decoder in Zoomplayer.

I rendered a .vob file into graphedit to check your supposition. I got the following filterchain:

Video: myvideo.vob>MPEG-2 Splitter>MPEGVideo Decoder>Video Renderer
Audio: myvideo.vob>MPEG-2 Splitter>Nvidia Audio Decoder>Default DirectSound Device
Playback with intermittent sound & no video
Replace MPEGVideo Decoder with Nvidia one: same scenario

With a Matroska media file with DTS only audio:

Video: mymovie.mkv>XVid Video Decoder>Video Renderer
Audio: mymovie.mkv>AVI<->AC3/DTS>Nvidia Audio Decoder>Default DirectSound Device
Playback in Graphedit OK.

If I uninstall the AC3XForm & reload DTS .mkv file into Graphedit, there is no audio chain?

Finally, after AC3XForm reinstall, when file playback in Zoomplayer. 'Rightclick>filers properties' shows video is playing with Nvidia video & audio decoders in DVD: Nvidia audio & XVid in Matroska file.

What else could I do to check it is really the Nvidia decoders operating?

I don't have the DVD specified in the Matroska test to check at present as a friend has it.

The problem I noticed is the Purevideo audio decoder Directshow output pin is not negotiating the AC3 tag with the Default Directshow audio renderer, and instead negotiating normal PCM channels. This seems to work for DD because I think the Purevideo decoder is still software decoding the DD signal, however whenever I try to play a DVD containing DTS, then there is no audio output. However if I configure GBPVR to use a different audio decoder (also with SPDIF pass-through configured), then all works. I have therefore come to the conclusion that SPDIF pass-through is not working correctly on the Purevideo audio decoder.

Would this not then indicate a blatant misrepresentation of the product's capabilities? What is the point of their decoders if they are not viable even with Window's own player?

I remember reading somewhere something about Dolby Inc. forcing Nvidia to cripple their audio decoder to third party players. But GB-PVR uses WMP as its default player so I don't why it should be affected.

Here is the thread.
http://forum.inmatrix.com/index.php?showtopic=3726

[csy]

Interesting, DTS obviously works for you, and as you pointed out, the AC3XForm filter is obviously required to extract the digital audio stream out of the Matroska container and link to the Purevideo audio decoder.

The linked thread says you can still use SPDIF pass-through even if there is a licencing restriction, and this is what I'm doing to my Audigy ZS soundcard and using the Audigy onboard DD/DTS decoder. I get a complete audio chain in graphedit but no DTS audio from DVD. If I replace the Directshow audio decoder filter with Cyberlink or Intervideo (also configured for SPDIF pass-through) then it works.

Anyway, I'm using an alternative audio decoder which works for me, so I'm not concerned with resolving my Purevideo audio DTS issue, but rather making other people aware of potential problems with Purevideo and DTS.

Thanks for your feedback gkar.

[gkar]

Thanks for your feedback gkar.

I, also enjoyed the discussion.

The linked thread says you can still use SPDIF pass-through even if there is a licencing restriction, and this is what I'm doing to my Audigy ZS soundcard and using the Audigy onboard DD/DTS decoder.

Is there any possibility the issue is with the soundcard drivers? Can you bypass the card for your mobo sound?

[gkar]

csy,

Which Purevideo decoder option did you purchase. Here's a snip from a site I use:

What level of decoder do I need? Bronze? Gold? or Platinum?

The NVIDIA Decoders come in 3 tiers. Which one you choose depends on your connection method:

Analog
If you are using analog surround sound speakers connected directly to your HTPC or a direct 6-channel analog connection to your home theater you'll probably want the Platinum edition because it decodes all Dolby formats and DTS.

The Gold decodes all the various Dolby formats but not DTS.

And the Bronze only decodes Dolby downsampled to stereo.


NOTE: The analog audio decoding features of the NVIDIA deocder only work in certified applications, which currently is limited to Windows Media Player or MCE 2005. However S/PDIF passthrough works in any application.

Digital
If you are using S/PDIF to connect to your home theater system or to a speaker system like the Logitech Z-680 the decoding abilities the decoder supports is moot. You can use the Bronze level since all you'll be doing is having it pass the audio onto a receiver via S/PDIF where the home theater receiver processes the digital signal itself.

Notice the one about the gold option.

Here's the link. http://www.htpcnews.com/forums/index.php...20763&st=0

[jksmurf]

1. The Purevideo audio decoder is buggy and I do not recommend using it.

Well, I installed the reg patch and I started getting a GREAT picture, but slightly staticky (is that a word ) audio. Hmm. What should I disable or should I just choose a different audio decoder?

It works fine with the Cyberlink A/V decoders, the (subjective view) picture doesn't seem to be quite as good as the Nvidia though.

k.

[nitrogen_widget]

Does pure video actually utilize a gforce 6200 or higher card for video rendering more than the cyberlink or winDVD decoder's?

I havn't had a chance to download a demo yet & compare them.

[csy]

You can mix'n'match video and audio decoders but can cause timing problems (FF/RW loss of audio etc). I use the Purevideo video decoder and Cyberlink audio decoder combination for DVD playback (only).

Nvidia and ATI mid/high-end video cards have inbuilt post-processing engine for sharpening and other similiar features. ATI have this always enabled, however early Nvidia drivers split the task between the Purevideo decoder and the post-processing engine. Nvidia is progressively migrating all the post-processing functionality to the video card so any video decoder can utilise it. As an example, the latest Nvidia drivers (91.31) has migrated the 3:2 pull-down function to the video card, and the latest Purevideo decoder (1.02-223) has removed the 'smart' de-interlacing function that used to provide it (although I acknowledge the 'smart' option is still seen as a config option).

IMO (but maybe wrong), providing you are using the latest Nvidia drivers, then the Nvidia video card post-processing engine functionality is enabled with all brands of Directshow video decoders.

I personally find the Purevideo, Cyberlink, and Intervideo video decoders all look very similiar when hardware de-interlacing is used, but Purevideo has the best timing synchronisation (smoothest horizontal ticker tape motion).