Antialiasing option in ResizeLanczos

[Ferran_Valldosera]

Hello,

Using ResizeSqrPixel one could use Lanczos with Antialiasing option (IPPI_ANTIALIASING). As ResizeSqrPixel is marked deprecated in IPP 7.1 I would like to know if one can still obtain same or similar results using ResizeLanczos (in IPP 7.1). Is there any way to specify antialiasing option for Lanczos in IPP 7.1? If not, should I expect more aliasing using Lanczos in IPP7.1 compared to IPP7.0?

Thanks,
Ferran

[Jeffrey_M_Intel1]

Hi Ferran, Antialiasing isn't available yet for the new resize functions. This functionality may be available in a future release. In the meantime, you can add your own antialiasing by "pre-blurring" the input image. The basic idea is to blur away features below the destination resolution. This can be accomplished with a box filter, using a mask of roughly the same size as the ratio of src/dst resolution. For example, when downsizing 1408x1152 to 352x288 you could use a 4x4 box filter mask. Please let me know if this is a realistic workaround for your case. Best regards, Jeff

[Ferran_Valldosera]

Thanks for your comments Jeff. After some initial tests I am unable though to get comparable quality (e.g. reducing aliasing) adding a box filter compared to what I used in IPP 7.0 (either Lanczos + Antialiasing with ippiResizeSqrPixel or using ippiResizeFilter with Lanzos interpolation). On the other hand, IPP 7.1 provides this new great capability of multithreaded tiled-based resizing using ResizeLanczos. I would then look forward to being able to either use the ResizeLanczos + antialiasing option or have a similar tiled-based resizing capability available when using ippiResizeFilter. Regards, Ferran