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Full Version: LiveTV playback has wrong AR on all but TV1
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I've just installed 1.5.31.

In LiveTV, TV1 is the only channel (1-9) that fills the window. Pressing the numeric keys to browse to another channel results in a squished/stretched video image in the top-left of the window. Random colours or large grey blocks appear where the video isn't. See the attached image(s) for a screenshot.

If I go back to TV1, aspect ratio is correct and the video fills the screen - but still only for that channel.

I have no such issue with Media Portal on the same machine.

Decoder settings are: VRM9; MPC MPEG2 Video Decoder (Gabest); h264: ArcSoft Decoder.
Windows XPsp3 with nVidia 8600GT card with latest drivers.
This is a bug in the nvidia video driver. Try either switching to EVR, or disable hardware acceleration in the video decoder.
I changed my video card to a 9600GT and updated the drivers to the latest, and the behaviour remains.

Oddly though, if I right-click and choose Aspect Ratio > Fill, the video correctly fills the screen and stays that way on all channels, from then on, regardless of channel, and channel changes.

Also, there are no such issues on the same machine in MediaPortal.

Sub, is there any way you could force an "Aspect Ratio > Fill" when LiveTV is first started (or an an option to do so), so I don't have to manually do it every time?
peter_h Wrote:I changed my video card to a 9600GT and updated the drivers to the latest, and the behaviour remains.
Thats because you've still got an nvidia card, so you still have this nvidia driver problem. The only way to avoid it is disable hardware acceleration in the decoder, or switch to EVR, or leave it in fill mode (with 16:9 channels on 16:9 tv), or use an ATI or other manufacturer card.

Quote:Also, there are no such issues on the same machine in MediaPortal.
This is because they're not using the Window's video renderer to display frames, but are instead using Direct3D to display the frames (much like the VMR9 Custom renderer in old GBPVR).

Quote:Sub, is there any way you could force an "Aspect Ratio > Fill" when LiveTV is first started (or an an option to do so), so I don't have to manually do it every time?
Sorry, not currently. I can try add somthing if you bump the thread in a couple of days though (busy with work stuff at the moment).
I have similar AR problems with an ATI 4550 card on XP using VMR9, VMR7 or EVR.
bdshaffer Wrote:I have similar AR problems with an ATI 4550 card on XP using VMR9, VMR7 or EVR.
With an ATI device, I'm sure you didnt have the same problem. The problem I referring to is a well known nvidia problem, and affects other apps too (DVBViewer, GBPVR etc). A thread on the nvidia forums about this problem can be found here: http://forums.nvidia.com/index.php?showtopic=15184

The characteristic symptoms of this are VMR, correct aspect ratio image in top/left but too small, and the rest of the screen filled with garbage from video memory.
Sub, if you'll recall from the early days of NPVR, a lot of us (including me) had exactly the same problems with ATI cards. My screens looked EXACTLY the same as peter_h's screenshot in the first post, and the behavior was the same - FILL was the only aspect ratio that worked. That got me bugging you again about supporting negative aspect ratios with EVR, and you did come up with a solution which has worked 100% great since then... so I've not worried about the issue since.

All I can conclude is that ATI has somehow adopted the same driver bug as nvidia.
No, I dont remember.

I'm personally using an ATI card, and have never seen anything like it, but clearly remember it with Nvidia cards. The bug was never acknowledged by nvidia though, and it may have been more of a Microsoft renderer bug related to a particular DXVA mode which Nvidia used. Nvidia and ATI traditionally used different DXVA modes, but I havnt checked in recent years, and maybe they're both using the same mode now (the previously nvidia only mode).

Either way, VMR is the past. Personally I'd recommend people go with Win7 and EVR.