[mythtv] Feasability of using software scalers in mythtv videoout
lists at wildgooses.com
Thu May 11 19:56:31 UTC 2006
>Ignore the jpeg artifacts, the pngs were a meg each, but note how much
>better picture quality you can get with the software scaler.
I only have a standard def TV, but I did similar experiments using
mplayer's software video output and came to the same conclusion as you.
Lanczos and bicubic splines are a pretty decent step up in quality
giving a sharper image (which doesn't look artificially sharpened).
Theoretically Lanczos is a mathematically more correct scaler (ie nearer
optimal), but in the literature it's often considered to be slightly
bettered by bicubic splines apparently because the artifacts (such that
there are) are more pleasing to the eye. However, to my eye both were
excellent and Lanczos was slightly sharper.
A good while back I hacked the software scaler in Myth to work for live
tv and although I didn't persue it to the point that it would play tv
smoothly it was clearly far better quality than the XV resize on my
NVidia 5200 card.
MPlayer would be a good point to start to examine the software playback
scalers since nothing is allowed into the mplayer code which has the
slightest bit of fat on it, so I should think their implementation is
More information about the mythtv-dev