Developer Reference

  • 2020
  • 07/15/2020
  • Public Content
Contents

Edge Smoothing

The
Smooth Edge
feature is an artificial method to reduce aliasing artifacts at the transformed source image edges. Aliasing artifacts may appear because the transformation algorithms skip a destination pixel if its source origin is out of the source image ROI. Thus, borders of the transformed source image can look stepped:
If the
smoothEdge
flag is set, destination pixels that are closest to the transformed source image edges are mixed with sampled source pixels by the following formula:
dstRes
=
srcSampled
*(1-
a
)+
dstExist
*
a
where
  • srcSampled
    is the intensity of the source pixel after transformation.
  • dstExist
    is the intensity of the destination pixel before transformation.
  • a
    is the weight of the outer pixel; set by the function.
  • dstRes
    is the intensity of the resulting destination pixel.
The edge smoothing method is not universal: in some cases it can improve the image, but in other cases it can be inefficient. For example, edge smoothing does not increase the quality of images with high contrast borders, and it is not recommended to apply edge smoothing to such images.
Edge smoothing is a post-processing operation: it is performed after transformation. When warping a tiled image, artifacts may appear on tile borders. In this case, edges are not smoothed.

Product and Performance Information

1

Intel's compilers may or may not optimize to the same degree for non-Intel microprocessors for optimizations that are not unique to Intel microprocessors. These optimizations include SSE2, SSE3, and SSSE3 instruction sets and other optimizations. Intel does not guarantee the availability, functionality, or effectiveness of any optimization on microprocessors not manufactured by Intel. Microprocessor-dependent optimizations in this product are intended for use with Intel microprocessors. Certain optimizations not specific to Intel microarchitecture are reserved for Intel microprocessors. Please refer to the applicable product User and Reference Guides for more information regarding the specific instruction sets covered by this notice.

Notice revision #20110804