FP16 to FP32 precision utilities

Overview

Set of functions to convert from FP32 to FP16 and vice versa. More…

// namespaces

namespace InferenceEngine::PrecisionUtils;
    namespace InferenceEngine::PrecisionUtils::details;

// typedefs

typedef short InferenceEngine::ie_fp16;

// global functions

ie_fp16 InferenceEngine::PrecisionUtils::f32tof16(float x);
float InferenceEngine::PrecisionUtils::f16tof32(ie_fp16 x);

void InferenceEngine::PrecisionUtils::f16tof32Arrays(
    float \* dst,
    const ie_fp16 \* src,
    size_t nelem,
    float scale = 1.f,
    float bias = 0.f
    );

void InferenceEngine::PrecisionUtils::f32tof16Arrays(
    ie_fp16 \* dst,
    const float \* src,
    size_t nelem,
    float scale = 1.f,
    float bias = 0.f
    );

template <
    class OutT,
    class InT,
    typename std::enable_if<std::is_integral<OutT>::value&&std::is_integral<InT>::value&&std::is_signed<InT>::value&&!std::is_same<OutT, InT>::value>::type \* = nullptr
    >
OutT InferenceEngine::PrecisionUtils::saturate_cast(const InT& value);

template <class InT>
InT InferenceEngine::PrecisionUtils::saturate_cast(const InT& value);

Detailed Documentation

Set of functions to convert from FP32 to FP16 and vice versa.

Typedefs

typedef short InferenceEngine::ie_fp16

A type difinition for FP16 data type. Defined as a singed short.

Global Functions

ie_fp16 InferenceEngine::PrecisionUtils::f32tof16(float x)

Converts a single-precision floating point value to a half-precision floating poit value.

Parameters:

x	A single-precision floating point value

Returns:

A half-precision floating point value

float InferenceEngine::PrecisionUtils::f16tof32(ie_fp16 x)

Convers a half-precision floating point value to a single-precision floating point value.

Parameters:

x	A half-precision floating point value

Returns:

A single-precision floating point value

void InferenceEngine::PrecisionUtils::f16tof32Arrays(
    float \* dst,
    const ie_fp16 \* src,
    size_t nelem,
    float scale = 1.f,
    float bias = 0.f
    )

Converts a half-precision floating point array to single-precision floating point array and applies scale and bias is needed.

Parameters:

dst	A destination array of single-precision floating point values
src	A source array of half-precision floating point values
nelem	A number of elements in arrays
scale	An optional scale parameter
bias	An optional bias parameter

void InferenceEngine::PrecisionUtils::f32tof16Arrays(
    ie_fp16 \* dst,
    const float \* src,
    size_t nelem,
    float scale = 1.f,
    float bias = 0.f
    )

Converts a single-precision floating point array to a half-precision floating point array and applies scale and bias if needed.

Parameters:

dst	A destination array of half-precision floating point values
src	A sources array of single-precision floating point values
nelem	A number of elements in arrays
scale	An optional scale parameter
bias	An optional bias parameter

template <
    class OutT,
    class InT,
    typename std::enable_if<std::is_integral<OutT>::value&&std::is_integral<InT>::value&&std::is_signed<InT>::value&&!std::is_same<OutT, InT>::value>::type \* = nullptr
    >
OutT InferenceEngine::PrecisionUtils::saturate_cast(const InT& value)

Converts one integral type to another saturating the result if the source value doesn’t fit into destination type range.

Parameters:

value

Value to be converted

Returns:

A saturated value

template <class InT>
InT InferenceEngine::PrecisionUtils::saturate_cast(const InT& value)

Converts one integral type to another saturating the result if the source value doesn’t fit into destination type range.

Parameters:

value

Value to be converted

Returns:

A saturated value