topic Resizing with subpixel precision - Ipp32f? in Intel® Integrated Performance Primitives

Resizing with subpixel precision - Ipp32f?

John_M_1 — Mon, 30 Jun 2014 19:40:54 GMT

If I want to work with Subpixel precision, I read on another post that someone is using Ipp32f types for that purpose.

But I fail to understand how that can help me.

If I have a Grayscale 16 image, where 1 pixel == 2 bytes, how would I represent the byte array in Ipp32f? And the function ippiResizeLinear_32f_C1R, for example, still takes IppiPoint and IppiSize which contain height and width in integers...

What am I missing here?

Hi John,If you need subpixel

Valentin_K_Intel — Tue, 01 Jul 2014 13:31:49 GMT

Hi John,

If you need subpixel precision, you can use the function ippiResizeSqrPixel_16u_C1R. It works with real scale factors and shifts, but this function is deprecated and can be removed in next releases. Alternatively, ippiWarpAffine_16u_C1R can be used for resize processing, because resize operation is the special case of an affine transformation. ippiWarpAffine is slow compared with ippiResizeSqrPixel, we are working on warp functions to reach better performance.

Regards, Valentin

Thank you Valentin,

John_M_1 — Wed, 02 Jul 2014 13:23:57 GMT

Thank you Valentin,

So, eventually when ippiResizeSqlPixel is dropped, ippiWarpAffine will be the ideal substitute for it?

Thanks

I consider that warp affine

Valentin_K_Intel — Mon, 07 Jul 2014 10:36:58 GMT

I consider that warp affine functions will be the most suitable for a resize transformation with subpixel precision, if ippiResizeSqlPixel is dropped.

Regards,
Valentin