Intel VAAPI howto with Leia v18 nightly based on Ubuntu 18.04 server
Quote:As noted above, In my recent quest for proper levels pass-through, I found I had to disable "Prefer VAAPI render method" not knowing what it does... Is it only necessary for interlaced content or does it also benefit progressive content? What is it exactly?

With the old intel vaapi implementation we had to use a method called vaPutSurface to transfer decoded data to our render. This Method would have scaled the colors to RGB Full Range. This introduced banding and bad quality. By disabling this feature, a CPU copy path would have been used. (All this is documented in the first thread).

Second problem here is, that intel's driver is doing limited range by default (no matter which kodi setting you tick). So also with your "Prefer VAAPI Render Method" disabled, you will get a double scaled picture ... and most likely only can correct it by upping the contrast (multiplicative operator):-(


With this code here in the thread. You can savely keep prefer vaapi method _enabled. This is even suggested. Make sure though, that your GPU runs at full range (see second post of this thread) to not do additional downscaling ...

What noggin meant with LiveTV: It's a heavy operation to copy things. After that it's a heavy operation to deinterlace things on the CPU -> so this approach is not practical on low power / low performance devices.

So: In order to enjoy perfect colors, just follow the howto.
First decide what functions / features you expect from a system. Then decide for the hardware. Don't waste your money on crap.
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Messages In This Thread
RE: New Era: VAAPI with EGL interoperation - by fritsch - 2015-09-18, 11:27
Live TV broken again? - by schamane - 2016-02-29, 19:56
Random crashes - by hal2100 - 2016-03-08, 22:03