| /* Copyright 2019 The TensorFlow Authors. All Rights Reserved. |
| |
| Licensed under the Apache License, Version 2.0 (the "License"); |
| you may not use this file except in compliance with the License. |
| You may obtain a copy of the License at |
| |
| http://www.apache.org/licenses/LICENSE-2.0 |
| |
| Unless required by applicable law or agreed to in writing, software |
| distributed under the License is distributed on an "AS IS" BASIS, |
| WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| See the License for the specific language governing permissions and |
| limitations under the License. |
| ==============================================================================*/ |
| #include "tensorflow/lite/kernels/internal/reference/quantize.h" |
| |
| #include "tensorflow/lite/c/common.h" |
| #include "tensorflow/lite/kernels/internal/quantization_util.h" |
| #include "tensorflow/lite/kernels/internal/reference/requantize.h" |
| #include "tensorflow/lite/kernels/internal/tensor_ctypes.h" |
| #include "tensorflow/lite/kernels/kernel_util.h" |
| #include "tensorflow/lite/micro/micro_utils.h" |
| |
| namespace tflite { |
| namespace ops { |
| namespace micro { |
| namespace quantize { |
| |
| struct OpData { |
| // The scaling factor from input to output (aka the 'real multiplier') can |
| // be represented as a fixed point multiplier plus a left shift. |
| int32_t output_multiplier; |
| int output_shift; |
| }; |
| |
| void* Init(TfLiteContext* context, const char* buffer, size_t length) { |
| TFLITE_DCHECK(context->AllocatePersistentBuffer != nullptr); |
| void* data = nullptr; |
| if (context->AllocatePersistentBuffer(context, sizeof(OpData), &data) == |
| kTfLiteError) { |
| return nullptr; |
| } |
| return data; |
| } |
| |
| TfLiteStatus Prepare(TfLiteContext* context, TfLiteNode* node) { |
| TFLITE_DCHECK(node->user_data != nullptr); |
| OpData* data = static_cast<OpData*>(node->user_data); |
| |
| TF_LITE_ENSURE_EQ(context, NumInputs(node), 1); |
| TF_LITE_ENSURE_EQ(context, NumOutputs(node), 1); |
| |
| const TfLiteTensor* input = GetInput(context, node, 0); |
| TfLiteTensor* output = GetOutput(context, node, 0); |
| |
| // TODO(b/128934713): Add support for fixed-point per-channel quantization. |
| // Currently this only support affine per-layer quantization. |
| TF_LITE_ENSURE_EQ(context, output->quantization.type, |
| kTfLiteAffineQuantization); |
| const auto* affine_quantization = |
| reinterpret_cast<TfLiteAffineQuantization*>(output->quantization.params); |
| TF_LITE_ENSURE(context, affine_quantization); |
| TF_LITE_ENSURE(context, affine_quantization->scale); |
| TF_LITE_ENSURE(context, affine_quantization->scale->size == 1); |
| |
| TF_LITE_ENSURE(context, input->type == kTfLiteFloat32 || |
| input->type == kTfLiteInt16 || |
| input->type == kTfLiteInt8); |
| TF_LITE_ENSURE(context, |
| output->type == kTfLiteUInt8 || output->type == kTfLiteInt8); |
| |
| if ((input->type == kTfLiteInt16 || input->type == kTfLiteInt8) && |
| output->type == kTfLiteInt8) { |
| double effective_scale = |
| static_cast<double>(input->params.scale / output->params.scale); |
| |
| QuantizeMultiplier(effective_scale, &data->output_multiplier, |
| &data->output_shift); |
| } |
| return kTfLiteOk; |
| } |
| |
| TfLiteStatus Eval(TfLiteContext* context, TfLiteNode* node) { |
| TFLITE_DCHECK(node->user_data != nullptr); |
| OpData* data = static_cast<OpData*>(node->user_data); |
| |
| const TfLiteTensor* input = GetInput(context, node, 0); |
| TfLiteTensor* output = GetOutput(context, node, 0); |
| |
| tflite::QuantizationParams op_params; |
| op_params.zero_point = output->params.zero_point; |
| op_params.scale = static_cast<double>(output->params.scale); |
| |
| if (input->type == kTfLiteFloat32) { |
| switch (output->type) { |
| case kTfLiteInt8: |
| reference_ops::AffineQuantize( |
| op_params, GetTensorShape(input), GetTensorData<float>(input), |
| GetTensorShape(output), GetTensorData<int8_t>(output)); |
| break; |
| case kTfLiteUInt8: |
| reference_ops::AffineQuantize( |
| op_params, GetTensorShape(input), GetTensorData<float>(input), |
| GetTensorShape(output), GetTensorData<uint8_t>(output)); |
| break; |
| default: |
| TF_LITE_KERNEL_LOG(context, "Input %s, output %s not supported.", |
| TfLiteTypeGetName(input->type), |
| TfLiteTypeGetName(output->type)); |
| return kTfLiteError; |
| } |
| } else if (input->type == kTfLiteInt16) { |
| size_t size = ElementCount(*input->dims); |
| switch (output->type) { |
| case kTfLiteInt8: |
| reference_ops::Requantize( |
| GetTensorData<int16_t>(input), size, data->output_multiplier, |
| data->output_shift, input->params.zero_point, |
| output->params.zero_point, GetTensorData<int8_t>(output)); |
| break; |
| default: |
| TF_LITE_KERNEL_LOG(context, "Input %s, output %s not supported.", |
| TfLiteTypeGetName(input->type), |
| TfLiteTypeGetName(output->type)); |
| return kTfLiteError; |
| } |
| } else if (input->type == kTfLiteInt8) { |
| // Int8 to Int8 requantization, required if the input and output tensors |
| // have different scales and/or zero points. |
| size_t size = ElementCount(*input->dims); |
| switch (output->type) { |
| case kTfLiteInt8: |
| reference_ops::Requantize( |
| GetTensorData<int8_t>(input), size, data->output_multiplier, |
| data->output_shift, input->params.zero_point, |
| output->params.zero_point, GetTensorData<int8_t>(output)); |
| break; |
| default: |
| TF_LITE_KERNEL_LOG(context, "Input %s, output %s not supported.", |
| TfLiteTypeGetName(input->type), |
| TfLiteTypeGetName(output->type)); |
| return kTfLiteError; |
| } |
| } else { |
| TF_LITE_KERNEL_LOG(context, "Input %s, output %s not supported.", |
| TfLiteTypeGetName(input->type), |
| TfLiteTypeGetName(output->type)); |
| return kTfLiteError; |
| } |
| |
| return kTfLiteOk; |
| } |
| |
| } // namespace quantize |
| |
| // This Op (QUANTIZE) quantizes the input and produces quantized output. |
| // AffineQuantize takes scale and zero point and quantizes the float value to |
| // quantized output, in int8 or uint8 format. |
| TfLiteRegistration* Register_QUANTIZE() { |
| static TfLiteRegistration r = {/*init=*/quantize::Init, |
| /*free=*/nullptr, |
| /*prepare=*/quantize::Prepare, |
| /*invoke=*/quantize::Eval, |
| /*profiling_string=*/nullptr, |
| /*builtin_code=*/0, |
| /*custom_name=*/nullptr, |
| /*version=*/0}; |
| return &r; |
| } |
| |
| } // namespace micro |
| } // namespace ops |
| } // namespace tflite |