Quote:
Originally Posted by 6233638
From looking at those numbers, I think that it would probably be best to use Bicubic 75 Chroma, which can be a significant visual improvement over Bilinear in many cases (often a close visual match to Lanczos or Jinc) for a minimal performance hit compared to Bilinear.
While I know that some people prefer softer Chroma settings, Bicubic 75 still seems to be the best balance between ringing/aliasing and maintaining the correct brightness/saturation for Chroma with a minimal performance hit. I wouldn't use it for Luma, but I've found almost nothing where it has caused problems for Chroma.
It may not be my personal preference, but I would then probably suggest using either Lanczos 3 or Spline 3 (probably Spline due to the reduced ringing) without the AR filter as the default for Luma upscaling.
The rendering times I posted are for comparative purposes from upscaling Blu-ray beyond 1080p, which is not indicative of real-world use (typically DVD or 720p up to 1080p) so I haven't run into any performance issues with playback when testing those settings yet. (almost 50ms would imply dropping frames)
If you're really wanting to reduce rendering times for your default, I would probably go with some level of SoftCubic for the Luma upscaling, but I know that's too soft for a lot of people. It does manage to avoid aliasing and ringing very well at higher levels though. The other Bicubic variants probably have too much ringing or aliasing to be suitable for the default Luma algorithm.
And now that I've overclocked the card (1GHz GPU/720MHz RAM) I seem to be able to play Blu-ray downscaled in linear light using Catmull-Rom AR without any problems, though it is probably still too taxing on some systems.
I still need to do a good performance and image quality test for downscaling algorithms. It's really not a priority for me though, as I use a 1080p native display, and the only time I downsample is when I have something playing at the side of a web browser, which is never a film, and therefore not particularly important to me as far as image quality is concerned.
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Nice point. I have a Dimension E521 (AMD Athlon™ 64 X2, 1GB RAM, Nvidia GeForce 6150LE) and using Bicubic 50 for chroma upscaling does look better than Bilinear. However, any number above 50 will cause 720p video to stutter (using LAV filters). Using Bicubic for luma/image upscaling will cause video to stutter as well. Bilinear seems to be the only option for luma upscaling to me.