Intel VAAPI howto with Leia v18 nightly based on Ubuntu 18.04 server
(2015-07-24, 08:58)wwessel Wrote:
(2015-07-23, 22:58)Hufvudet Wrote: Neither of these routes below should give you crushed blacks. But it's important, at least on my Pana st60, that you don't trust auto settings for rgb, at least not when going limited:

- Full range with xrandr, tv and kodi + dithering enabled: Best option if I watch my own photos + movies. Super small compromise with movies but dithering takes care of artifacts from expansion.

- Full range xrandr, limited kodi + tv: best option if I only watch movies - purest color handling with no expansion. I enable dithering here also.

I tested these settings, too. On my TV the second one seems to be the best, since I'm watching movies only. But I can't see a difference between limited range with/without dithering.

@fritsch: Does dithering affect the output in limited range? The discription says: Enable dithering when using full range...

You shouldn't need to enable dithering when outputting limited range, in theory. But from what understand you might need it if you don't have a perfectly mastered source, which you very seldom have. From madshi on this (same thinking should apply to kodi):

It is true that with a prefect color neutral grayscale, letting madVR render to 16-235 means that madVR doesn't have to dither. However, even black & white movies are usually not 100% color neutral. They often have a slight color tint. And as soon as chroma is anything but exactly color neutral, madVR instantly has to dither. Which is the case for 99.99% of all movies out there. And once madVR dithers, it shouldn't matter too much whether you configure madVR to output PC or TV levels.

Yeah, sure, in theory having madVR output 16-235 should be slightly better. But in real life I don't think there's much of a difference between 16-235 and 0-255 output. Of course 16-235 allows the preservation of BTB/WTW, which might be a plus because some displays might be calibrated to show a tiny tiny bit of BTB/WTW or something.

With that said, you can definately see a difference with dithering on/off in full range. In limited range I've only found short passages in a few films where color transitioning appears smoother with dithering enabled. That's why I leave it on. It shouldn't hurt picture quality either way.

Messages In This Thread
RE: New Era: VAAPI with EGL interoperation - by Hufvudet - 2015-07-24, 09:31
Live TV broken again? - by schamane - 2016-02-29, 19:56
Random crashes - by hal2100 - 2016-03-08, 22:03