Hello,I am using ippiColorTwist (more precisely ippiColorTwist32f_16_C3IR) for a 1024x1024 image with 3 samples per pixel, 2 bytes per sample. The average measured time is about 12ms, almost the same as running my C implementation for the same processing. The C implementation performs the operations described herehttp://software.intel.com/sites/products/documentation/hpc/composerxe/en-us/ippxe/ipp_manual_lnx/index.htmplus a simple rounding to 0 for negative numbers.Why is ippiColorTwist so slow? Am I missing something?Here are the details about my configurations:- Intel Core2 email@example.com GHz- Windows 7 Ultimate, 64-bit-using static linkage with dispatching for the IPP library- ippInit() is called before any other ipp function- ippiGetLibVersion() returns: major = 7 minor = 0 majorBuild = 205 build = 1020 targetCpu = "u8" Name = "ippiu8_l.lib" Version = "7.0 build 205.23" BuildDate = "Sep 1 2010"- using Visual Studio 2008- C implementation is compiled for Release, X64 with Full Optimization (/0x)Thank you.
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