Horizontal scaler
There are several horizontal scalers. A special case worth mentioning is
- the fast bilinear scaler that is made of runtime-generated MMX2 code
+ the fast bilinear scaler that is made of runtime-generated MMXEXT code
using specially tuned pshufw instructions.
The remaining scalers are specially-tuned for various filter lengths.
They scale 8-bit unsigned planar data to 16-bit signed planar data.