| # Copyright © 2020 Arm Ltd and Contributors. All rights reserved. |
| # SPDX-License-Identifier: MIT |
| |
| import os |
| from typing import List, Tuple |
| |
| import pyarmnn as ann |
| import numpy as np |
| |
| |
| def create_network(model_file: str, backends: list, input_names: Tuple[str] = (), output_names: Tuple[str] = ()): |
| """ |
| Creates a network based on the model file and a list of backends. |
| |
| Args: |
| model_file: User-specified model file. |
| backends: List of backends to optimize network. |
| input_names: |
| output_names: |
| |
| Returns: |
| net_id: Unique ID of the network to run. |
| runtime: Runtime context for executing inference. |
| input_binding_info: Contains essential information about the model input. |
| output_binding_info: Used to map output tensor and its memory. |
| """ |
| if not os.path.exists(model_file): |
| raise FileNotFoundError(f'Model file not found for: {model_file}') |
| |
| _, ext = os.path.splitext(model_file) |
| if ext == '.tflite': |
| parser = ann.ITfLiteParser() |
| else: |
| raise ValueError("Supplied model file type is not supported. Supported types are [ tflite ]") |
| |
| network = parser.CreateNetworkFromBinaryFile(model_file) |
| |
| # Specify backends to optimize network |
| preferred_backends = [] |
| for b in backends: |
| preferred_backends.append(ann.BackendId(b)) |
| |
| # Select appropriate device context and optimize the network for that device |
| options = ann.CreationOptions() |
| runtime = ann.IRuntime(options) |
| opt_network, messages = ann.Optimize(network, preferred_backends, runtime.GetDeviceSpec(), |
| ann.OptimizerOptions()) |
| print(f'Preferred backends: {backends}\n{runtime.GetDeviceSpec()}\n' |
| f'Optimization warnings: {messages}') |
| |
| # Load the optimized network onto the Runtime device |
| net_id, _ = runtime.LoadNetwork(opt_network) |
| |
| # Get input and output binding information |
| graph_id = parser.GetSubgraphCount() - 1 |
| input_names = parser.GetSubgraphInputTensorNames(graph_id) |
| input_binding_info = parser.GetNetworkInputBindingInfo(graph_id, input_names[0]) |
| output_names = parser.GetSubgraphOutputTensorNames(graph_id) |
| output_binding_info = [] |
| for output_name in output_names: |
| out_bind_info = parser.GetNetworkOutputBindingInfo(graph_id, output_name) |
| output_binding_info.append(out_bind_info) |
| return net_id, runtime, input_binding_info, output_binding_info |
| |
| |
| def execute_network(input_tensors: list, output_tensors: list, runtime, net_id: int) -> List[np.ndarray]: |
| """ |
| Executes inference for the loaded network. |
| |
| Args: |
| input_tensors: The input frame tensor. |
| output_tensors: The output tensor from output node. |
| runtime: Runtime context for executing inference. |
| net_id: Unique ID of the network to run. |
| |
| Returns: |
| list: Inference results as a list of ndarrays. |
| """ |
| runtime.EnqueueWorkload(net_id, input_tensors, output_tensors) |
| output = ann.workload_tensors_to_ndarray(output_tensors) |
| return output |
| |
| |
| class ArmnnNetworkExecutor: |
| |
| def __init__(self, model_file: str, backends: list): |
| """ |
| Creates an inference executor for a given network and a list of backends. |
| |
| Args: |
| model_file: User-specified model file. |
| backends: List of backends to optimize network. |
| """ |
| self.network_id, self.runtime, self.input_binding_info, self.output_binding_info = create_network(model_file, |
| backends) |
| self.output_tensors = ann.make_output_tensors(self.output_binding_info) |
| |
| def run(self, input_tensors: list) -> List[np.ndarray]: |
| """ |
| Executes inference for the loaded network. |
| |
| Args: |
| input_tensors: The input frame tensor. |
| |
| Returns: |
| list: Inference results as a list of ndarrays. |
| """ |
| return execute_network(input_tensors, self.output_tensors, self.runtime, self.network_id) |