ClassesClasses | | Operators

optimize_rft_speedoptimize_rft_speedOptimizeRftSpeedOptimizeRftSpeed (Operator)


optimize_rft_speedoptimize_rft_speedOptimizeRftSpeedOptimizeRftSpeed — Optimize the runtime of the real-valued FFT.


optimize_rft_speed( : : Width, Height, Mode : )

Herror optimize_rft_speed(const Hlong Width, const Hlong Height, const char* Mode)

Herror T_optimize_rft_speed(const Htuple Width, const Htuple Height, const Htuple Mode)

void OptimizeRftSpeed(const HTuple& Width, const HTuple& Height, const HTuple& Mode)

static void HMisc::OptimizeRftSpeed(Hlong Width, Hlong Height, const HString& Mode)

static void HMisc::OptimizeRftSpeed(Hlong Width, Hlong Height, const char* Mode)

static void HOperatorSet.OptimizeRftSpeed(HTuple width, HTuple height, HTuple mode)

static void HMisc.OptimizeRftSpeed(int width, int height, string mode)


optimize_rft_speedoptimize_rft_speedOptimizeRftSpeedOptimizeRftSpeedOptimizeRftSpeed determines a method that achieves an optimum runtime of the real-valued FFT for an image of size WidthWidthWidthWidthwidth x HeightHeightHeightHeightheight. The data that are determined for one image size do not influence the methods used for other image sizes. Consequently, optimize_rft_speedoptimize_rft_speedOptimizeRftSpeedOptimizeRftSpeedOptimizeRftSpeed can be called multiple times with different values for WidthWidthWidthWidthwidth and HeightHeightHeightHeightheight to achieve an optimum runtime for all image sizes that are used in an application. The parameter ModeModeModeModemode determines the thoroughness of the search for the fastest method. For ModeModeModeModemode = 'standard'"standard""standard""standard""standard" a fast search is used, which typically takes a few seconds. The method thus determined results in very good runtimes, which are not always optimal. For ModeModeModeModemode = 'patient'"patient""patient""patient""patient" a more thorough search is performed, which typically takes several seconds and in most cases leads to optimum runtimes. For ModeModeModeModemode = 'exhaustive'"exhaustive""exhaustive""exhaustive""exhaustive" an exhaustive search is performed, which typically takes several minutes and always results in the optimum runtime. In most applications, ModeModeModeModemode = 'standard'"standard""standard""standard""standard" results in the best compromise between the runtime of the real-valued FFT and the time required for the search of the optimum runtime. The data determined with optimize_rft_speedoptimize_rft_speedOptimizeRftSpeedOptimizeRftSpeedOptimizeRftSpeed can be saved with write_fft_optimization_datawrite_fft_optimization_dataWriteFftOptimizationDataWriteFftOptimizationDataWriteFftOptimizationData and can be loaded with read_fft_optimization_dataread_fft_optimization_dataReadFftOptimizationDataReadFftOptimizationDataReadFftOptimizationData.

Please note that this optimization is performed for the particular computer on which the operator is called. The results are not suited to be transferred and used on other computers unless they have the same hardware and software configuration including the driver versions.

optimize_rft_speedoptimize_rft_speedOptimizeRftSpeedOptimizeRftSpeedOptimizeRftSpeed influences the runtime of rft_genericrft_genericRftGenericRftGenericRftGeneric.

Execution Information


WidthWidthWidthWidthwidth (input_control)  integer HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Width of the image for which the runtime should be optimized.

Default value: 512

Suggested values: 128, 160, 192, 256, 320, 384, 512, 640, 768, 1024, 2048

HeightHeightHeightHeightheight (input_control)  integer HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Height of the image for which the runtime should be optimized.

Default value: 512

Suggested values: 120, 128, 144, 240, 256, 288, 480, 512, 576, 1024, 2048

ModeModeModeModemode (input_control)  string HTupleHTupleHtuple (string) (string) (HString) (char*)

Thoroughness of the search for the optimum runtime.

Default value: 'standard' "standard" "standard" "standard" "standard"

List of values: 'exhaustive'"exhaustive""exhaustive""exhaustive""exhaustive", 'patient'"patient""patient""patient""patient", 'standard'"standard""standard""standard""standard"


optimize_rft_speedoptimize_rft_speedOptimizeRftSpeedOptimizeRftSpeedOptimizeRftSpeed returns 2 (H_MSG_TRUE) if all parameters are correct. If necessary, an exception is raised.

Possible Successors

rft_genericrft_genericRftGenericRftGenericRftGeneric, write_fft_optimization_datawrite_fft_optimization_dataWriteFftOptimizationDataWriteFftOptimizationDataWriteFftOptimizationData



See also




ClassesClasses | | Operators