Quicksync inappropriate default settings?

[Deleted User 11865]

For Trellis afaik API 1.6 is enough.

Nope, the mfxCodingOption2 Trellis field was added in API 1.7 - so you need that API to control it, at least. Therefore the option itself requires API 1.7.

Do you know if GopOptFlag (page 138 mediasdk) can be useful?

Well, I've wired a "scenecut" option that controls MFX_GOP_STRICT, but it's undocumented because it's not really useful except for testing sometimes.

Open-GOP support is on my TO-DO list, but not really a priority.

[gmb]

I thought Lookahead was the only new feature in 1.7 but release notes indeed mentioned Trellis as well. I don't understand why Trellis is only available in TU1 and not for TU4. It would be much more useful it we could use it in TU4.

[gmb]

Is it still on your TO-DO list?

[Deleted User 11865]

Yes, but so are many other things. I haven't had time to do much work on QSV lately.

[gmb]

Ok understand. I just wonder if open gop can help on some videos where Intel suffer from a bad gop behavior. This is Intels main issue imo.

[gmb]

Once again default settings are broken. Best quality gives fps=GopPicSize.

[Deleted User 11865]

That's what's been recommended to us recently. Here's the deal: while your input is very valuable, I'd like to run some more comprehensive tests myself (there are some bugs that take priority over this testing, which is why I till haven't gotten around to it). Until then, I'll stick with official recommendations when it comes to default settings.

That doesn't prevent you from sharing your own preferred settings, I'm sure some forum readers will find them useful

[gmb]

They recommended fps=GopPicSize? What is the reason behind this exactly? Do they think it gives better quality? Intel official GopPicSize is 256. For better understanding it would be important to know why one or some people from Intel doesn't follow Intels own Media SDK default GopPicSize. I mean this was one reason for anandtech's Quicksync image quality regression from Haswell 6 months ago.