[MPlayer-users] Comparison of different software scaler types

[Matthias Wieser]

Hi,

I have done a small webpage, showing the effects of different software 
scaler types (-sws x).

First I used mplayer to scale video frames down to 50%. Those frames were 
saved as PNGs. Then I used imagemagic to scale them back to original 
size, so you don't need a magnifying glass to see small details.

At http://www.wieser-web.de/MPlayer/ you can see the differences.

Results:
- sws 0    produces acceptable results
- sws 1    produces blurred images
- sws 2    produces very good images
- sws 7    is even worse than -sws 1
- sws 8    produces shadows near strong edges and increases contrast
- sws 9/10 produce the fewest artifacts and gives even a bit better
           results than -sws 2

If software scaling filters are repeated
(-vf scale=600:500,scale=550:427,scale=440:344,scale=340:264 -sws 10)
colors change heavily. Bug?

     Matthias