| /* |
| * Copyright (c) 2019-2022 Arm Limited. |
| * |
| * SPDX-License-Identifier: MIT |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to |
| * deal in the Software without restriction, including without limitation the |
| * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or |
| * sell copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in all |
| * copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| * SOFTWARE. |
| */ |
| #ifndef ARM_COMPUTE_QUANTIZATION_INFO_H |
| #define ARM_COMPUTE_QUANTIZATION_INFO_H |
| |
| #include "arm_compute/core/Error.h" |
| #include "arm_compute/core/Rounding.h" |
| #include "support/ToolchainSupport.h" |
| #include "utils/misc/Utility.h" |
| |
| #include <cstddef> |
| #include <type_traits> |
| #include <vector> |
| |
| namespace arm_compute |
| { |
| using qasymm8_signed_t = int8_t; /**< 8 bit signed quantized asymmetric scalar value */ |
| using qasymm8_t = uint8_t; /**< 8 bit quantized asymmetric scalar value */ |
| using qsymm16_t = int16_t; /**< 16 bit quantized symmetric scalar value */ |
| using qasymm16_t = uint16_t; /**< 16 bit quantized asymmetric scalar value */ |
| |
| /** Quantization info when assuming per layer quantization */ |
| struct UniformQuantizationInfo |
| { |
| /** Default constructor */ |
| UniformQuantizationInfo() |
| : scale(0.f), offset(0) |
| { |
| } |
| /** Constructor |
| * |
| * @param[in] scale Quantization scale |
| * @param[in] offset Quantization offset |
| */ |
| UniformQuantizationInfo(float scale, int32_t offset) |
| : scale(scale), offset(offset) |
| { |
| } |
| /** Checks if the scale and offset are both zero */ |
| bool empty() const |
| { |
| return (scale == 0) && (offset == 0); |
| } |
| |
| float scale; |
| int32_t offset; |
| }; |
| |
| /** Quantization information */ |
| class QuantizationInfo |
| { |
| public: |
| /** Default constructor */ |
| QuantizationInfo() noexcept |
| : _scale(), |
| _offset() |
| { |
| } |
| /** Construct quantization info. |
| * |
| * @note Used for symmetric quantization |
| * |
| * @param[in] scale Scale. |
| */ |
| QuantizationInfo(float scale) |
| : _scale(1, scale), _offset() |
| { |
| } |
| /** Construct quantization info. |
| * |
| * @note Used for asymmetric quantization |
| * |
| * @param[in] scale Scale. |
| * @param[in] offset Offset. |
| */ |
| QuantizationInfo(float scale, int offset) |
| : _scale(1, scale), _offset(1, offset) |
| { |
| } |
| /** Construct quantization info. |
| * |
| * @note Used for symmetric per channel quantization |
| * |
| * @param[in] scale Scale. |
| */ |
| QuantizationInfo(std::vector<float> scale) |
| : _scale(scale), _offset() |
| { |
| } |
| /** Construct quantization info. |
| * |
| * @note Used for asymmetric per channel quantization |
| * |
| * @param[in] scale Scale. |
| * @param[in] offset Offset. |
| */ |
| QuantizationInfo(std::vector<float> scale, std::vector<int32_t> offset) |
| : _scale(scale), _offset(offset) |
| { |
| } |
| /** Scale vector accessor |
| * |
| * @return A reference to quantization scale metadata |
| */ |
| const std::vector<float> &scale() const |
| { |
| return _scale; |
| } |
| /** Offset vector accessor |
| * |
| * @return A reference to quantization offset metadata |
| */ |
| const std::vector<int32_t> &offset() const |
| { |
| return _offset; |
| } |
| /** Indicates whether this QuantizationInfo has valid settings or not |
| * |
| * @return True if the this has invalid settings. |
| */ |
| bool empty() const |
| { |
| return _scale.empty() && _offset.empty(); |
| } |
| /** Return per layer quantization info |
| * |
| * @return Uniform quantization information in case of empty information zero is returned in the respective fields |
| */ |
| UniformQuantizationInfo uniform() const |
| { |
| UniformQuantizationInfo uqinfo; |
| uqinfo.scale = _scale.empty() ? 0 : _scale[0]; |
| uqinfo.offset = _offset.empty() ? 0 : _offset[0]; |
| |
| return uqinfo; |
| } |
| |
| private: |
| std::vector<float> _scale; /**< Vector containing scaling factors */ |
| std::vector<int32_t> _offset; /**< Vector containing zero offsets */ |
| }; |
| |
| /** Check whether two quantization info are equal. |
| * |
| * @param[in] lhs RHS quantization info. |
| * @param[in] rhs LHS quantization info. |
| * |
| * @return True if the given quantization info is the same. |
| */ |
| inline bool operator==(const QuantizationInfo &lhs, const QuantizationInfo &rhs) |
| { |
| return (lhs.scale() == rhs.scale()) && (lhs.offset() == rhs.offset()); |
| } |
| |
| /** Check whether two quantization info are not equal. |
| * |
| * @param[in] lhs RHS quantization info. |
| * @param[in] rhs LHS quantization info. |
| * |
| * @return True if the given quantization info is the same. |
| */ |
| inline bool operator!=(const QuantizationInfo &lhs, const QuantizationInfo &rhs) |
| { |
| return !(operator==(lhs, rhs)); |
| } |
| |
| /** Check whether two quantization info are equal. |
| * |
| * @param[in] lhs RHS quantization info. |
| * @param[in] rhs LHS quantization info. |
| * |
| * @return True if the given quantization info is the same. |
| */ |
| inline bool operator==(const UniformQuantizationInfo &lhs, const UniformQuantizationInfo &rhs) |
| { |
| return (lhs.scale == rhs.scale) && (lhs.offset == rhs.offset); |
| } |
| |
| /** Check whether two quantization info are not equal. |
| * |
| * @param[in] lhs RHS quantization info. |
| * @param[in] rhs LHS quantization info. |
| * |
| * @return True if the given quantization info is the same. |
| */ |
| inline bool operator!=(const UniformQuantizationInfo &lhs, const UniformQuantizationInfo &rhs) |
| { |
| return !(operator==(lhs, rhs)); |
| } |
| template <typename QUANTIZED_TYPE = uint8_t> |
| struct Qasymm8QuantizationHelper |
| { |
| static_assert(std::is_same<QUANTIZED_TYPE, uint8_t>::value |
| || std::is_same<QUANTIZED_TYPE, int8_t>::value, |
| "quantized type should be either uint8_t or int8_t."); |
| |
| /** Quantize a value given a 8-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to quantize |
| * @param[in] qinfo Quantization information to use for quantizing |
| * |
| * @return Quantized value |
| */ |
| static inline QUANTIZED_TYPE quantize(float value, const UniformQuantizationInfo &qinfo) |
| { |
| ARM_COMPUTE_ERROR_ON(qinfo.scale == 0); |
| const int quantized = support::cpp11::lround(value / qinfo.scale) + qinfo.offset; |
| return static_cast<QUANTIZED_TYPE>(arm_compute::utility::clamp<decltype(quantized), QUANTIZED_TYPE>(quantized)); |
| } |
| |
| /** Quantize a value given a 8-bit asymmetric quantization scheme using a specific rounding policy |
| * |
| * @param[in] value Value to quantize |
| * @param[in] qinfo Quantization information to use for quantizing |
| * @param[in] rounding_policy Rounding policy to use |
| * |
| * @return Quantized value |
| */ |
| static inline QUANTIZED_TYPE quantize(float value, const UniformQuantizationInfo &qinfo, RoundingPolicy rounding_policy) |
| { |
| if(rounding_policy == RoundingPolicy::TO_NEAREST_UP) |
| { |
| return quantize(value, qinfo); |
| } |
| |
| ARM_COMPUTE_ERROR_ON(qinfo.scale == 0); |
| const int quantized = arm_compute::round(value / qinfo.scale, rounding_policy) + qinfo.offset; |
| return static_cast<QUANTIZED_TYPE>(arm_compute::utility::clamp<decltype(quantized), QUANTIZED_TYPE>(quantized)); |
| } |
| |
| /** Quantize a value given a 8-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to quantize |
| * @param[in] qinfo Quantization information to use for quantizing |
| * @param[in] rounding_policy (Optional) Rounding policy to use. Default: nearest up |
| * |
| * @return Quantized value |
| */ |
| static inline QUANTIZED_TYPE quantize(float value, const QuantizationInfo &qinfo, RoundingPolicy rounding_policy = RoundingPolicy::TO_NEAREST_UP) |
| { |
| const UniformQuantizationInfo uqinfo = qinfo.uniform(); |
| ARM_COMPUTE_ERROR_ON(uqinfo.scale == 0); |
| const int quantized = arm_compute::round(value / uqinfo.scale, rounding_policy) + uqinfo.offset; |
| return static_cast<QUANTIZED_TYPE>(arm_compute::utility::clamp<decltype(quantized), QUANTIZED_TYPE>(quantized)); |
| } |
| |
| /** Dequantize a value given a 8-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] qinfo Quantization information to use for dequantizing |
| * |
| * @return Dequantized value |
| */ |
| static inline float dequantize(QUANTIZED_TYPE value, const UniformQuantizationInfo &qinfo) |
| { |
| return (static_cast<int>(value) - qinfo.offset) * qinfo.scale; |
| } |
| |
| /** Dequantize a value given a 8-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] qinfo Quantization information to use for dequantizing |
| * |
| * @return Dequantized value |
| */ |
| static inline float dequantize(QUANTIZED_TYPE value, const QuantizationInfo &qinfo) |
| { |
| const UniformQuantizationInfo uqinfo = qinfo.uniform(); |
| return (static_cast<int>(value) - uqinfo.offset) * uqinfo.scale; |
| } |
| }; |
| |
| /** Quantize a value given an unsigned 8-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to quantize |
| * @param[in] qinfo Quantization information to use for quantizing |
| * @param[in] rounding_policy (Optional) Rounding policy to use. Default: nearest up |
| * |
| * @return Quantized value |
| */ |
| template <typename INFO_TYPE> |
| inline uint8_t quantize_qasymm8(float value, const INFO_TYPE &qinfo, RoundingPolicy rounding_policy = RoundingPolicy::TO_NEAREST_UP) |
| { |
| return Qasymm8QuantizationHelper<uint8_t>::quantize(value, qinfo, rounding_policy); |
| } |
| |
| /** Quantize a value given a signed 8-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to quantize |
| * @param[in] qinfo Quantization information to use for quantizing |
| * @param[in] rounding_policy (Optional) Rounding policy to use. Default: nearest up |
| * |
| * @return Quantized value |
| */ |
| template <typename INFO_TYPE> |
| inline int8_t quantize_qasymm8_signed(float value, const INFO_TYPE &qinfo, RoundingPolicy rounding_policy = RoundingPolicy::TO_NEAREST_UP) |
| { |
| return Qasymm8QuantizationHelper<int8_t>::quantize(value, qinfo, rounding_policy); |
| } |
| |
| /** Quantize a value given a 8-bit symmetric quantization scheme |
| * |
| * @param[in] value Value to quantize |
| * @param[in] qinfo Quantization information to use for quantizing |
| * |
| * @return Quantized value |
| */ |
| inline int8_t quantize_qsymm8(float value, const QuantizationInfo &qinfo) |
| { |
| int quantized = arm_compute::round(value / qinfo.uniform().scale, RoundingPolicy::TO_NEAREST_UP); |
| quantized = std::max(-128, std::min(quantized, 127)); |
| return quantized; |
| } |
| |
| /** Quantize a value given a 8-bit symmetric per channel quantization scheme |
| * |
| * @param[in] value Value to quantize |
| * @param[in] qinfo Quantization information to use for quantizing |
| * @param[in] channel_id channel index into the scale vector of quantization info |
| * |
| * @return Quantized value |
| */ |
| inline int8_t quantize_qsymm8_per_channel(float value, const QuantizationInfo &qinfo, size_t channel_id = 0) |
| { |
| int quantized = arm_compute::round(value / qinfo.scale()[channel_id], RoundingPolicy::TO_NEAREST_UP); |
| quantized = std::max(-128, std::min(quantized, 127)); |
| return quantized; |
| } |
| |
| /** Dequantize a value given an unsigned 8-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] qinfo Quantization information to use for dequantizing |
| * |
| * @return Dequantized value |
| */ |
| template <typename INFO_TYPE> |
| inline float dequantize_qasymm8(uint8_t value, const INFO_TYPE &qinfo) |
| { |
| return Qasymm8QuantizationHelper<uint8_t>::dequantize(value, qinfo); |
| } |
| |
| /** Dequantize a value given a signed 8-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] qinfo Quantization information to use for dequantizing |
| * |
| * @return Dequantized value |
| */ |
| template <typename INFO_TYPE> |
| inline float dequantize_qasymm8_signed(int8_t value, const INFO_TYPE &qinfo) |
| { |
| return Qasymm8QuantizationHelper<int8_t>::dequantize(value, qinfo); |
| } |
| |
| /** Dequantize a value given an 8-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] scale Scale to use for dequantization |
| * @param[in] offset Zero-offset to use for dequantization |
| * |
| * @return Dequantized value |
| */ |
| inline float dequantize(uint8_t value, float scale, int32_t offset) |
| { |
| return (static_cast<int>(value) - offset) * scale; |
| } |
| |
| /** Dequantize a value given a 8-bit symmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] qinfo Quantization information to use for dequantizing |
| * |
| * @return Dequantized value |
| */ |
| inline float dequantize_qsymm8(int8_t value, const UniformQuantizationInfo &qinfo) |
| { |
| return value * qinfo.scale; |
| } |
| |
| inline qasymm8_t qasymm8_hard_swish(qasymm8_t in, |
| const UniformQuantizationInfo &qi_in, |
| const UniformQuantizationInfo &qi_out) |
| { |
| float tmp_f = dequantize_qasymm8(in, qi_in); |
| tmp_f = tmp_f * ((std::min(std::max((tmp_f + 3), 0.0f), 6.0f)) * 0.166666667f); |
| const qasymm8_t tmp = quantize_qasymm8(tmp_f, qi_out); |
| return tmp; |
| } |
| |
| inline qasymm8_signed_t qasymm8_signed_hard_swish(qasymm8_signed_t in, |
| const UniformQuantizationInfo &qi_in, |
| const UniformQuantizationInfo &qi_out) |
| { |
| float tmp_f = dequantize_qasymm8_signed(in, qi_in); |
| tmp_f = tmp_f * ((std::min(std::max((tmp_f + 3), 0.0f), 6.0f)) * 0.166666667f); |
| const qasymm8_t tmp = quantize_qasymm8_signed(tmp_f, qi_out); |
| return tmp; |
| } |
| |
| inline qasymm8_t qasymm8_leaky_relu(qasymm8_t in, |
| const UniformQuantizationInfo &qi_in, |
| const UniformQuantizationInfo &qi_out, |
| float alpha) |
| { |
| float tmp_f = dequantize_qasymm8(in, qi_in); |
| tmp_f = tmp_f > 0 ? tmp_f : tmp_f * alpha; |
| const qasymm8_t tmp = quantize_qasymm8(tmp_f, qi_out); |
| return tmp; |
| } |
| |
| inline qasymm8_t qasymm8_logistic(qasymm8_t in, |
| const UniformQuantizationInfo &qi_in, |
| const UniformQuantizationInfo &qi_out) |
| { |
| float tmp_f = dequantize_qasymm8(in, qi_in); |
| tmp_f = 1.f / (1.f + std::exp(-tmp_f)); |
| const qasymm8_t tmp = quantize_qasymm8(tmp_f, qi_out); |
| return tmp; |
| } |
| |
| inline qasymm8_signed_t qasymm8_signed_logistic(qasymm8_signed_t in, |
| const UniformQuantizationInfo &qi_in, |
| const UniformQuantizationInfo &qi_out) |
| { |
| float tmp_f = dequantize_qasymm8_signed(in, qi_in); |
| tmp_f = 1.f / (1.f + std::exp(-tmp_f)); |
| const qasymm8_signed_t tmp = quantize_qasymm8_signed(tmp_f, qi_out); |
| return tmp; |
| } |
| |
| /** Dequantize a value given a 8-bit symmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] scale Scale to use for dequantization |
| * |
| * @return Dequantized value |
| */ |
| inline float dequantize(int8_t value, float scale) |
| { |
| return value * scale; |
| } |
| |
| /** Dequantize a value given a 16-bit symmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] scale Scale to use for dequantization |
| * |
| * @return Dequantized value |
| */ |
| inline float dequantize(int16_t value, float scale) |
| { |
| return value * scale; |
| } |
| |
| /** Dequantize a value given a 16-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] scale Scale to use for dequantization |
| * @param[in] offset Zero-offset to use for dequantization |
| * |
| * @return Dequantized value |
| */ |
| inline float dequantize(uint16_t value, float scale, int32_t offset) |
| { |
| return (static_cast<int>(value) - offset) * scale; |
| } |
| |
| /** Quantize a value given a 16-bit symmetric quantization scheme |
| * |
| * @param[in] value Value to quantize |
| * @param[in] qinfo Quantization information to use for quantizing |
| * @param[in] rounding_policy (Optional) Rounding policy to use. Default: nearest up |
| * |
| * @return Quantized value |
| */ |
| inline int16_t quantize_qsymm16(float value, const UniformQuantizationInfo &qinfo, RoundingPolicy rounding_policy = RoundingPolicy::TO_NEAREST_UP) |
| { |
| int quantized = arm_compute::round(value / qinfo.scale, rounding_policy); |
| quantized = arm_compute::utility::clamp<int, int16_t>(quantized); |
| return quantized; |
| } |
| |
| /** Dequantize a value given a 16-bit symmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] qinfo Quantization information to use for dequantizing |
| * |
| * @return Dequantized value |
| */ |
| inline float dequantize_qsymm16(int16_t value, const UniformQuantizationInfo &qinfo) |
| { |
| return value * qinfo.scale; |
| } |
| |
| /** Quantize a value given a 16-bit symmetric quantization scheme |
| * |
| * @param[in] value Value to quantize |
| * @param[in] qinfo Quantization information to use for quantizing |
| * |
| * @return Quantized value |
| */ |
| inline int16_t quantize_qsymm16(float value, const QuantizationInfo &qinfo) |
| { |
| return quantize_qsymm16(value, qinfo.uniform()); |
| } |
| |
| /** Dequantize a value given a 16-bit symmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] qinfo Quantization information to use for dequantizing |
| * |
| * @return Dequantized value |
| */ |
| inline float dequantize_qsymm16(int16_t value, const QuantizationInfo &qinfo) |
| { |
| return dequantize_qsymm16(value, qinfo.uniform()); |
| } |
| |
| /** Quantize a value given a 16-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to quantize |
| * @param[in] qinfo Quantization information to use for quantizing |
| * @param[in] rounding_policy (Optional) Rounding policy to use. Default: nearest up |
| * |
| * @return Quantized value |
| */ |
| inline uint16_t quantize_qasymm16(float value, const UniformQuantizationInfo &qinfo, RoundingPolicy rounding_policy = RoundingPolicy::TO_NEAREST_UP) |
| { |
| int quantized = arm_compute::round(value / qinfo.scale, rounding_policy) + qinfo.offset; |
| quantized = arm_compute::utility::clamp<int, uint16_t>(quantized); |
| return quantized; |
| } |
| |
| /** Dequantize a value given a 16-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] qinfo Quantization information to use for dequantizing |
| * |
| * @return Dequantized value |
| */ |
| inline float dequantize_qasymm16(uint16_t value, const UniformQuantizationInfo &qinfo) |
| { |
| return (static_cast<int>(value) - qinfo.offset) * qinfo.scale; |
| } |
| |
| /** Quantize a value given a 16-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to quantize |
| * @param[in] qinfo Quantization information to use for quantizing |
| * |
| * @return Quantized value |
| */ |
| inline uint16_t quantize_qasymm16(float value, const QuantizationInfo &qinfo) |
| { |
| return quantize_qasymm16(value, qinfo.uniform()); |
| } |
| |
| /** Dequantize a value given a 16-bit asymmetric quantization scheme |
| * |
| * @param[in] value Value to dequantize |
| * @param[in] qinfo Quantization information to use for dequantizing |
| * |
| * @return Dequantized value |
| */ |
| inline float dequantize_qasymm16(uint16_t value, const QuantizationInfo &qinfo) |
| { |
| return dequantize_qasymm16(value, qinfo.uniform()); |
| } |
| |
| /* |
| * In case of requantization of a quantized input tensor to an output tensor with another quantization |
| * instead of applying dequantization and then a quantization functions, we just compute new scale and |
| * offset. |
| * |
| * Assuming: |
| * - q_i as input quantized value |
| * - q_o as output quantized value |
| * - z_i as input quantization offset value |
| * - z_o as output quantization offset value |
| * - s_i as input quantization scale value |
| * - s_o as output quantization scale value |
| * - z_n as new quantization offset value |
| * - s_n as new quantization scale value |
| * |
| * q_o = ( q_i - z_i ) * s_i / s_o + z_o |
| * |
| * We can rewrite the formula as: |
| * |
| * q_o = ( q_i * s_i / s_o ) - z_i * s_i / s_o + z_o |
| * |
| * q_o = q_i / s_n + z_n |
| * |
| * Where: |
| * |
| * s_n = s_o / s_i |
| * |
| * z_n = - z_i * s_i / s_o + z_o |
| * |
| */ |
| inline UniformQuantizationInfo compute_requantization_scale_offset(const UniformQuantizationInfo &uqinfo_in, const UniformQuantizationInfo &uqinfo_out) |
| { |
| float scale_to_apply = uqinfo_out.scale; |
| int32_t offset_to_apply = uqinfo_out.offset; |
| |
| scale_to_apply /= uqinfo_in.scale; |
| // In order to minimize flooring we convert the offset to a float, |
| // then compute the new offset in the float domain, |
| // finally we convert it back as int32_t |
| offset_to_apply -= static_cast<int32_t>(static_cast<float>(uqinfo_in.offset) * uqinfo_in.scale / uqinfo_out.scale); |
| return UniformQuantizationInfo(scale_to_apply, offset_to_apply); |
| } |
| |
| } // namespace arm_compute |
| #endif /* ARM_COMPUTE_QUANTIZATION_INFO_H */ |