GB-PVR interface with DirectShow; need Live TV filter info

[Braklet]

I'm trying to sort through some DirectShow filter and graph oddities on my system, using a combination of GSpot and GraphEdit.

Live TV, recorded dvr-ms (ATSC receiver) files and mpg (PVR-500) files play fine. GraphEdit renders appropriate graphs from recorded files using the nVidia video/audio decoders as they should. GSpot, however can't render a graph from DirectShow defaults.

I'd like to know what filters get included for Live TV play, but GraphEdit always pukes on GB-PVRs lastgraph.grf. I get a popup complaining about "unrecognized filter" or something similar.

Note that I've configured GB-PVR playback parameters for "System Default," though I've gotten the same problem configuring GB-PVR to specifically use the PureVideo decoders.

I suspect a problem with nVidia PureVideo filter registration, _not_ GB-PVR. But I need to get more visibility into GB-PVRs interface with DirectShow to narrow the problem down.

The reason I'm digging into this is because I'd like to add ffdshow filters to my system in order to play e.g. MPEG4 media, but I don't want them to take precedence over PureVideo for MPEG2. Whenever ffdshow filters are enabled they always interfere with nVidia PureVideo filters and mess up my video quality. Live TV won't play from within GB-PVR at all while ffdshow filters are enabled.

Anybody have tips for extracting a usable filter graph from GB-PVR?

Thanks!

[sub]

I'd like to know what filters get included for Live TV play, but GraphEdit always pukes on GB-PVRs lastgraph.grf. I get a popup complaining about "unrecognized filter" or something similar.

Note that I've configured GB-PVR playback parameters for "System Default," though I've gotten the same problem configuring GB-PVR to specifically use the PureVideo decoders.

If you view live tv, then look in the gbpvr.exe-native.log, you'll see a list of all the filters that were used for live tv.

[Braklet]

If you view live tv, then look in the gbpvr.exe-native.log, you'll see a list of all the filters that were used for live tv.

Very cool. I'll check that out tonight.

Thanks for the tip, sub!

Has anyone else tried digging into the DirectShow filters? I wish there was a way for me to design a good working graph with GraphEdit, then somehow "burn" those settings into the registry.

[sub]

I wish there was a way for me to design a good working graph with GraphEdit, then somehow "burn" those settings into the registry.

sorry, it aint that straight forward...

[Braklet]

sorry, it aint that straight forward...

Oh, I'm unfortunately aware of that.

I gather the only way to define a graph is programmatically or depend on the well wishes and good thinking of DirectShow?

Here is the best reference information I've found thus far on how DirectShow goes about building a graph for a particular piece of media.

In my case I believe DirectShow is always falling through to #3 check byte determination. I am trying to figure out how the rest of the registry is structured so that I can hopefully repair or enhance PureVideo's registration.

I've already spent so much time manually editing filter Merit values that I wonder if ffdshow hacked something else to insert itself into every graph. I have no other explanation for how a 0x200001 merit filter would take precedence over a 0x800005 filter.

I have to leave ffdshow audio/video decoders effectively disabled at 0x200000 just to keep my system happy. Can't play MPEG4 that way. How ridiculous.

[sub]

I gather the only way to define a graph is programmatically or depend on the well wishes and good thinking of DirectShow?

When it comes to MPEG2 files, and you've specified the decoders and renderers you want to use, then GB-PVR pretty much tells directshow exactly how it wants to use and how they're connected - and this is usually obeyed unless some decoder cant be created or wont connect for some reason.

When it comes to other file types like MPEG4, divx/xvid etc, then GB-PVR just lets Windows decide what filters to use.

[sub]

Did you configure your ffdshow settings to have MPEG2 support disabled?

[Braklet]

Did you configure your ffdshow settings to have MPEG2 support disabled?

I thought so, but quite possibly not. I haven't been inclined to dig into ffdshow guts yet. My fear is that if I get ffdshow to stop inserting its video decoder into everything, then I'll have to worry about its audio decoder (I still want to use nVidia for audio, too). Every time I've seen that little "FF" icon down on the Taskbar, I've dropped a lot of frames so I just want to eliminate it for everything remotely MPEG2 related.

[Braklet]

When it comes to MPEG2 files, and you've specified the decoders and renderers you want to use, then GB-PVR pretty much tells directshow exactly how it wants to use and how they're connected - and this is usually obeyed unless some decoder cant be created or wont connect for some reason.

Hmm, that's part of my problem. Once I added HD playback I got a large # of dropped frames with GB-PVR configured to use nVidia audio & video decoders. When I changed GB-PVR to System Default, things got a LOT better. I have no idea why.

So I'm a little curious about the graph GB-PVR tells DirectShow to use. Thus far I've just gotten away with DirectShow defaults so I'm trying to learn about the filter registration just to make sense of all that stuff GSpot talks about.

[sub]

As I mentioned above, you can look in gbpvr.exe-native.log, then compare the list of filters when you using system default vs explicitly specifying the decoders to see what the difference is. If the list is the same, then the performance should be the same.