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Rajeev Rao aff45dd565 TensorRT OSS 8.0 release
Signed-off-by: Rajeev Rao <rajeevrao@nvidia.com>
2021-07-02 16:35:44 -07:00

159 lines
6.3 KiB
Python

#
# Copyright (c) 2021, NVIDIA CORPORATION. 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.
#
import os
import sys
import argparse
import numpy as np
import tensorrt as trt
import pycuda.driver as cuda
import pycuda.autoinit
from image_batcher import ImageBatcher
class TensorRTInfer:
"""
Implements inference for the EfficientNet TensorRT engine.
"""
def __init__(self, engine_path):
"""
:param engine_path: The path to the serialized engine to load from disk.
"""
# Load TRT engine
self.logger = trt.Logger(trt.Logger.ERROR)
with open(engine_path, "rb") as f, trt.Runtime(self.logger) as runtime:
self.engine = runtime.deserialize_cuda_engine(f.read())
self.context = self.engine.create_execution_context()
assert self.engine
assert self.context
# Setup I/O bindings
self.inputs = []
self.outputs = []
self.allocations = []
for i in range(self.engine.num_bindings):
is_input = False
if self.engine.binding_is_input(i):
is_input = True
name = self.engine.get_binding_name(i)
dtype = self.engine.get_binding_dtype(i)
shape = self.engine.get_binding_shape(i)
if is_input:
self.batch_size = shape[0]
size = np.dtype(trt.nptype(dtype)).itemsize
for s in shape:
size *= s
allocation = cuda.mem_alloc(size)
binding = {
'index': i,
'name': name,
'dtype': np.dtype(trt.nptype(dtype)),
'shape': list(shape),
'allocation': allocation,
}
self.allocations.append(allocation)
if self.engine.binding_is_input(i):
self.inputs.append(binding)
else:
self.outputs.append(binding)
assert self.batch_size > 0
assert len(self.inputs) > 0
assert len(self.outputs) > 0
assert len(self.allocations) > 0
def input_spec(self):
"""
Get the specs for the input tensor of the network. Useful to prepare memory allocations.
:return: Two items, the shape of the input tensor and its (numpy) datatype.
"""
return self.inputs[0]['shape'], self.inputs[0]['dtype']
def output_spec(self):
"""
Get the specs for the output tensor of the network. Useful to prepare memory allocations.
:return: Two items, the shape of the output tensor and its (numpy) datatype.
"""
return self.outputs[0]['shape'], self.outputs[0]['dtype']
def infer(self, batch, top=1):
"""
Execute inference on a batch of images. The images should already be batched and preprocessed, as prepared by
the ImageBatcher class. Memory copying to and from the GPU device will be performed here.
:param batch: A numpy array holding the image batch.
:param top: The number of classes to return as top_predicitons, in descending order by their score. By default,
setting to one will return the same as the maximum score class. Useful for Top-5 accuracy metrics in validation.
:return: Three items, as numpy arrays for each batch image: The maximum score class, the corresponding maximum
score, and a list of the top N classes and scores.
"""
# Prepare the output data
output = np.zeros(*self.output_spec())
# Process I/O and execute the network
cuda.memcpy_htod(self.inputs[0]['allocation'], np.ascontiguousarray(batch))
self.context.execute_v2(self.allocations)
cuda.memcpy_dtoh(output, self.outputs[0]['allocation'])
# Process the results
classes = np.argmax(output, axis=1)
scores = np.max(output, axis=1)
top = min(top, output.shape[1])
top_classes = np.flip(np.argsort(output, axis=1), axis=1)[:, 0:top]
top_scores = np.flip(np.sort(output, axis=1), axis=1)[:, 0:top]
return classes, scores, [top_classes, top_scores]
def main(args):
trt_infer = TensorRTInfer(args.engine)
batcher = ImageBatcher(args.input, *trt_infer.input_spec(), preprocessor=args.preprocessor)
for batch, images in batcher.get_batch():
classes, scores, top = trt_infer.infer(batch)
for i in range(len(images)):
if args.top == 1:
print(images[i], classes[i], scores[i], sep=args.separator)
else:
line = [images[i]]
assert args.top <= top[0].shape[1]
for t in range(args.top):
line.append(str(top[0][i][t]))
for t in range(args.top):
line.append(str(top[1][i][t]))
print(args.separator.join(line))
if __name__ == "__main__":
parser = argparse.ArgumentParser()
parser.add_argument("-e", "--engine", help="The TensorRT engine to infer with")
parser.add_argument("-i", "--input",
help="The input to infer, either a single image path, or a directory of images")
parser.add_argument("-t", "--top", default=1, type=int,
help="The amount of top classes and scores to output per image, default: 1")
parser.add_argument("-s", "--separator", default="\t",
help="Separator to use between columns when printing the results, default: \\t")
parser.add_argument("-p", "--preprocessor", default="V2", choices=["V1", "V1MS", "V2"],
help="Select the image preprocessor to use, either 'V2', 'V1' or 'V1MS', default: V2")
args = parser.parse_args()
if not all([args.engine, args.input]):
parser.print_help()
print("\nThese arguments are required: --engine and --input")
sys.exit(1)
main(args)