[maaim]

I'm sure that this may have been discussed elsewhere, but the current video quality in the Live TV/PVR application is lacking.

I run NeXTPVR as a backend on WIN 7 64. Currently running a Hauppage Colossus cap card.

With the Colossus you get a copy of the ArcSoft Showbiz application. The difference between the ArcSoft live TV capture and the XBMC version are night and day. ArcSoft is clear, clean with bright colors and great resolution, whereas the current XBMC implementation is soft, dull, and grainy.

I understand that the codec that ArcSoft uses is proprietary but it's such a glaring difference.

Any chance that the codec for LiveTV on XBMC is going to be updated in one of the future releases? Or is there a way to remedy this now? I've tried the pre-builds of Gotham (13) and they really aren't any better.

Anyone found a way to improve this?

Thanks in advance

[sub3]

Some times the Hauppauge Colossus device doesn't correctly report it's resolution, causing NextPVR to think it's standard def, which in turn causes it to use a lower bitrate. Try increasing the default bitrate settings in <ModeSD> section of NextPVR's config.xml to see if it helps.

[maaim]

That did seem to help. Thank you sub3!

Still seems a little off in action scenes. Is it possible to change the codec used by NextPVR for the streaming video?

[saitoh183]

in XBMC make sure you turn on deinterlacing in the video settings http://wiki.xbmc.org/index.php?title=Video_playback

This will help with the picture quality if your using 1080i on your set top box. I set mine to the max of the colossus :

Code:

<ModeSD>
      <Bitrate>20000000</Bitrate>
      <BitratePeak>24000000</BitratePeak>
      <BitrateMode>VBR</BitrateMode>
    </ModeSD>

[maaim]

Ok starting to make some progress.

I set the <ModeSD> in NextPVR to 20000000 and 24000000 respectively. I also changed the bit rates for 720, 1080 as well.

I then went and changed the codec for NextPVR from EVR to madVR. madVR is much better but also more GPU intensive so don't try it unless you're running a decent GPU.

I also registered the codecs from ArcSoft and added them as defaults for playback in NextPVR. This won't effect the live streaming play but helps with playback.

Next go to the video settings in XBMC and turn Deinterlace on, and change the DXVA type to DXVA Best. It's a little confusing finding these settings in XBMC 12.2 and 13. The easiest way is to start Live TV, then click on the "reel" icon. That will bring you to the video settings and allow you to set them as default for all videos.

So far the difference is immense.

I'm not sure there's an easier way to do this other than what I've done but hopefully it'll help someone.

Thanks again to sub3 and saitoh183 for the suggestions!

[sub3]

Still seems a little off in action scenes. Is it possible to change the codec used by NextPVR for the streaming video?

NextPVR always just supplies the original video stream produced by the Colossus.

---

Ok starting to make some progress.

I set the <ModeSD> in NextPVR to 20000000 and 24000000 respectively. I also changed the bit rates for 720, 1080 as well.

That's pretty high - you'd probably find you don't get much benefit over about 14Mbps. Have it too high will result in massive recordings, and make it more problematic for streaming since it's having to send a lot of data over the network to the XBMC client, for very little visual improvement.

I then went and changed the codec for NextPVR from EVR to madVR. madVR is much better but also more GPU intensive so don't try it unless you're running a decent GPU.

I also registered the codecs from ArcSoft and added them as defaults for playback in NextPVR. This won't effect the live streaming play but helps with playback.

It's worth noting these types of settings won't make any difference if you're using XBMC, since it'll be using XBMC playback components. These decoder/renderer changes will only help if you're using the NextPVR front end. (also not sure about the madVR renderer recommendation - I've never had much luck with it, and doesn't work that well with NextPVR).

[saitoh183]

Still seems a little off in action scenes. Is it possible to change the codec used by NextPVR for the streaming video?

NextPVR always just supplies the original video stream produced by the Colossus.

---

Ok starting to make some progress.

I set the <ModeSD> in NextPVR to 20000000 and 24000000 respectively. I also changed the bit rates for 720, 1080 as well.

That's pretty high - you'd probably find you don't get much benefit over about 14Mbps. Have it too high will result in massive recordings, and make it more problematic for streaming since it's having to send a lot of data over the network to the XBMC client, for very little visual improvement.

1h show (50min) = 4GB TS file
30min show (22-25min = 2GB TS file

Playing with the rates i always got the best and most constant results with my set top box using max. Might depend on the set top box being used. Since i only kep my recordings till i watch them, then delete them, file size doesnt matter and my network seems to handle it well.

[sub3]

Fair enough. Use whatever works well for you.

[maaim]

Thanks sub3 for the clarifications. I'll play around with it a bit to see what gives the best live performance without a huge file size.

So far I'm liking the madVR renderer, but I'll give it some time to see what the long term results are.

Thank you both for the help! I really appreciate it!