Running Inference with DeepStream, but with unknown model architecture

Accelerated Computing Intelligent Video Analytics DeepStream SDK
1

Hello there.

I have a trained single-class object detection model, in TensorFlow SavedModel format, which runs at a nominal 10 FPS on an Nvidia Jetson TX2.

At first, I attempted to convert the model to use TensorRT inference, but that simply produced a significantly less accurate model that ran about .3 FPS faster in most situations.

I then began looking into using DeepStream to accelerate the inference, but there’s one crucial problem: I don’t know what model architecture the model is using. I can’t identify whether the model is using Faster R-CNN, SSD, or YOLO, and as such cannot use the current object detection plugins.

The model was generated for me by Google Cloud AutoML Vision Edge. It has an input named encoded_image_string_tensor:0 that takes a (in Python terms) byte-encoded JPEG, PNG or GIF file, and outputs the usual detection_scores:0, detection_boxes:0, etc.

What should I do? I need at least a little bit higher performance to make this a viable usage. Thanks!

2

Hi,

The detector used in deepstream is pruned ResNet model and you can find more information here:
https://devtalk.nvidia.com/default/topic/1069706/transfer-learning-toolkit/transfer-learning-toolkit-detectnet_v2-example-walk-through/post/5418813/#5418813

May I know how do you convert the model into TensorRT? Are you using TF-TRT or pure TensorRT?
Here is a tutorial for the popular object detection TensorFlow model into TensorRT:
https://github.com/AastaNV/TRT_object_detection

It’s recommended to check it first.

Thanks.

3

Hi AastaLLL,

Here’s my code that I’ve been using to convert the model with TF-TRT. I’ve been using TensorFlow 2.1.0 with TensorRT 6 on CUDA 10.2.

import tensorflow as tf
import numpy as np
import cv2
import sys
from tensorflow.python.compiler.tensorrt import trt_convert as trt

conversion_params = trt.DEFAULT_TRT_CONVERSION_PARAMS
conversion_params = conversion_params._replace(max_workspace_size_bytes=(1<<32))
conversion_params = conversion_params._replace(precision_mode="FP16")
conversion_params = conversion_params._replace(maximum_cached_engines=100)

converter = trt.TrtGraphConverterV2(
    input_saved_model_dir=sys.argv[1],
    conversion_params=conversion_params
)
converter.convert()
def input_fn():
    for _ in range(128):
        inp = np.random.normal(size=(512, 512, 3)).astype(np.float32)
        result, output = cv2.imencode(".jpg", inp)
        yield output.tobytes()

converter.build(input=input_fn)

converter.save(sys.argv[2])

Unfortunately, it always gets me an error on my development system of:

2020-02-10 08:00:20.388739: E tensorflow/core/grappler/grappler_item_builder.cc:656] Init node index_to_string/table_init/LookupTableImportV2 doesn't exist in graph
Traceback (most recent call last):
  File "run.py", line 15, in <module>
    converter.convert()
  File "/usr/local/lib/python3.6/dist-packages/tensorflow_core/python/compiler/tensorrt/trt_convert.py", line 980, in convert
    frozen_func = convert_to_constants.convert_variables_to_constants_v2(func)
  File "/usr/local/lib/python3.6/dist-packages/tensorflow_core/python/framework/convert_to_constants.py", line 428, in convert_variables_to_constants_v2
    graph_def = _run_inline_graph_optimization(func, lower_control_flow)
  File "/usr/local/lib/python3.6/dist-packages/tensorflow_core/python/framework/convert_to_constants.py", line 127, in _run_inline_graph_optimization
    return tf_optimizer.OptimizeGraph(config, meta_graph)
  File "/usr/local/lib/python3.6/dist-packages/tensorflow_core/python/grappler/tf_optimizer.py", line 59, in OptimizeGraph
    strip_default_attributes)
tensorflow.python.framework.errors_impl.InvalidArgumentError: Failed to import metagraph, check error log for more info.

On my Jetson, it does work; however, it becomes less precise and has significantly lower recall.

Unfortunately, this means for me that using TF-TRT (at least, with default settings) will not work
for my application.

I turned to DeepStream, and while it will work for getting video input and sending the output, I don’t know how to write an nvinfer plugin for a DeepStream inference implementation.

I can provide the model if you wish to take a closer look; it isn’t anything proprietary to me.

4

Here’s the link to the model: https://drive.google.com/file/d/1adT6cB7uGxcQbTYzZK5ErcQ9t4Tri3xf/view?usp=sharing

5

Hi,

Please noticed that TensorRT start to support TensorFlow 2.0 from TRT7.0.
For Jetson, you will need a TensorFlow 1.x model for compatibility.

Thanks.

6

I’ll try upgrading my version of TensorFlow to 2.0 on the Jetson and report back. Thanks.