Hi, 2014-06-17 9:13 GMT+02:00 Jean-Yves Avenard <[email protected]>: > [was replied privately by mistake. Resending it to the list] > > Hi > > On Tuesday, June 17, 2014, Gwenole Beauchesne <[email protected]> wrote: >> Yes, I know, I only answered to Rainer and wanted to experiment >> something on your case before commenting. > > > And what did your experimentation returns? :)
I mentioned below that I see a possible optimization in the driver, not that I have definitely tested it either. :) > Right now; what I've done (currently only in use in mythtv) is a > USWCCopy class that the first time it is called to perform either a > frame copy or a nv12->yv12 conversion, is timed the two different > routines and select the fastest one for future use. > It's certainly not pretty, nor elegant; but it works reliably seeing > that the USWC copy methods is clearly faster in one case, and clearly > slower in the other. > > > >> > Any recommendations? >>An optimization is indeed possible on the driver, in case you create a VA >>image. >>BTW, for VLC, the issue with using vaGetImage() is that the driver >>currently does not provide bitexact conversion from NV12 to I420/YV12. >>This is an issue that needs to be fixed at lest for same size >>conversions. Otherwise, the the "Advanced Video Scaler" (AVS) engine >>is always used, which tries to enhance the image along the way. > > > I can't say I've been able to visualise the difference with moving > images. But I haven't looked in that much details anyway. > VaGetImage returned frame certainly good enough. > > > With vaDeriveImage, 30% of the time spent in processing a frame from > file to display is actually the NV12->YV12 conversion. Even with fenrir's optimization to split the UV planes? Could be worth checking if you observe the same behaviour in Windows. Thanks. Regards, -- Gwenole Beauchesne Intel Corporation SAS / 2 rue de Paris, 92196 Meudon Cedex, France Registration Number (RCS): Nanterre B 302 456 199 _______________________________________________ Libva mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/libva
