Developer Guide and Reference

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Example 5

Example 5 converts a 2D image from the RGB format to the YUV format. It demonstrates how storing both images in 2D SoA
n_container
s can improve performance.
#include <iostream> #include <sdlt/sdlt.h> using namespace sdlt; #define WIDTH 1024 #define HEIGHT 1024 struct RGBs { float r; float g; float b; }; struct YUVs { float y; float u; float v; YUVs(){ }; YUVs& operator=(const RGBs &tmp){ y = 0.229f * tmp.r + 0.587f * tmp.g + 0.114f * tmp.b; u = -0.147f * tmp.r - 0.289f * tmp.g + 0.436f * tmp.b; v = 0.615 * tmp.r - 0.515f * tmp.g - 0.100 * tmp.b; return *this; } YUVs(const RGBs &tmp){ y = 0.229f * tmp.r + 0.587f * tmp.g + 0.114f * tmp.b; u = -0.147f * tmp.r - 0.289f * tmp.g + 0.436f * tmp.b; v = 0.615 * tmp.r - 0.515f * tmp.g - 0.100 * tmp.b; } }; SDLT_PRIMITIVE(RGBs, r, g, b) SDLT_PRIMITIVE(YUVs, y, u, v) int main(){ typedef layout::soa<> LayoutT; n_extent_t<int, int> extents(HEIGHT, WIDTH); /* Creating a typedef for SoA N-dimensional container. RGBTy and YUVTy are user defined structures whose collection needs to be stored in SoA format in memory. Layout in memory specified as layout::soa. In the below case N-dimensional SoA container is used in 2-D context */ typedef sdlt::n_container< RGBs, LayoutT, decltype(extents) > ContainerRGB; typedef sdlt::n_container< YUVs, LayoutT, decltype(extents) > ContainerYUV; //Instantiate Input and Output Containers ContainerRGB inputRGB(extents); ContainerYUV outputYUV(extents); auto input = inputRGB.const_access(); //Get Constant Accessor object for inputRGB auto output = outputYUV.access(); //Get Accessor object for outputYUV //Select the iteration range in each dimension const auto iRGB1 = bounds_d<1>(input); //bound_d<1>(input); const auto iRGB0 = bounds_d<0>(input); //bound_d<0>(input); for(int y = iRGB0.lower(); y < iRGB0.upper(); y++) { #pragma simd for (int x = iRGB1.lower(); x < iRGB1.upper(); x++){ const RGBs temp1 = input[y][x]; YUVs temp2 = temp1; output[y][x] = temp2; } } return 0; }

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.