Aspect Ratio

[sflamm]

I'm having some difficulty with the aspect ratio of the picture I get. Here is the scenario. There are 2 channels: channel A is an SD channel broadcast at 4:3, channel B is an HD channel broadcast in HD at 16:9

When I set the GB-PVR aspect ratio control to Widescren (16x9) then channel A looks terrible (the picture only occupys about 3/4 of the screen horizontally and 7/8 vertically and has garbage where the picture is not) and channel B looks great.

When I set the GB-PVR aspect ratio control to Standard (4x3) then channel A looks great and channel B looks terrible (very narrow band occupying only the top 1/2 of the window).

How can I configure GB-PVR such that it will look good independent of the source?


My desktop monitor is 1440x 900. I am running GB-PVR windowed (though the same issue occurs when I maximize it to full-screen). I have also set my monitor to other standard dimensions (i.e. 1024x768 etc) and this does not change anything.

This is GB-PVR 99.12

[sub]

I can see from your screenshot that something other than GB-PVR is trying to manage the aspect ratio on your setup, and its conflicting with GB-PVR's aspect ratio control. I can tell that because the OSD does not go to the edges of the screen, like it normally would when GB-PVR is only thing managing this.

If you're using the nvidia decoder, you need to go into the settings and set the aspect ratio mode to 'anamorphic' otherwise you'll see exactly this behaviour shown in your screenshots.

[sflamm]

You were right, that the nvidia decoder was not set to "anamorphic raw".

With that said, it didnt fix the issue. Below is the same HD content in 4:3 aspect with nvidia decoder set to "anamorphic/raw"

Attachments of new screen shot and nvidia settings dialog...

[sub]

You forgot the attachment.

Also, make sure you've got your tv shape set correctly, and you've explicitly selected your video decoder in the config app (rather than relying on system default - which means GB-PVR will not be able to detect the current video info).

[sflamm]

Sorry I updated the attachments, and here is the GB-PVR config dialog:

[sflamm]

I ran the MuxChecker -just out of curiosity, and it has issues too...

I am running Windows XP SP2 / MCE and I also have Cyberlink PowerDVD 7.1 installed (both MCE and PowerDVD work perfectly)

[sflamm]

I've noticed that when the program 1st starts it is correct for about 1/2 second. Then it resizes to what you see in the picture above (I think this is driven by the program information overlay). Perhaps it is simply never returning to the correct size.

Not sure if that helps you in any way...

[sub]

If you disable the hardware acceleration tick in the nvidia decoder settings, does it show correctly? or alternatively switch to the VMR9 Custom renderer.

[sflamm]

I turned off hardware acceleration and now it seems to work. I tried both configuration successfully.

The downside is of course that the video is a bit slower, a bit jerky and the audio seems like it occasionally gets a little out of sink.

Not sure how much of that is due to the hardware acceleration vs other programs running on my computer...

Do you know why the hardware acceleration has that effect?

[sub]

What you're seeing is the nvidia aspect ratio driver bug. http://forums.nvidia.com/index.php?showtopic=15184&st=0

Normally people see garbage on the rest of the screen, but I guess in your case you were just lucky enough to have the rest of the video memory in a nice clean state, which resulted in black garbage.

The work arounds are to disable hardware acceleration, or use VMR9 Custom, or use old nvidia videocard drivers.