TensorFlow Object Detection Starter

TensorFlow Object Detection Starter is a sample project also a guide of how you can train your own data for object detection.

Now we're working on the easiest one, which is called "Image Retraining".

Preparation

• Install Python 3.6.x (At this moment the Tensorflow does not support Python 3.7.x)
• Install TensorFlow & TensorFlow Hub

pip install tensorflow
pip install tensorflow_hub

Note: if you have seen this kind of error: could not find a version that satisfies the requirement tensorflow, please Use Python 3.6.x.

• Prepare the images to be trained & verified (tested), please check them here for example, tag the pictures by naming the folders

Retraining

There is an official tutorial of How to Retrain an Image Classifier for New Categories

python retrain.py --image_dir=samples/retrain/ \
--saved_model_dir=result/saved_model/ \
--output_graph=result/foo.pb \
--output_labels=result/foo.txt \
-—bottleneck_dir=result/bottleneck/ \
--summaries_dir=result/retrain_logs/ \
-—intermediate_output_graphs_dir=result/intermediate_graph/ \
--tfhub_module=https://tfhub.dev/google/imagenet/mobilenet_v2_100_224/feature_vector/1 \
--how_many_training_steps=4000

After running through the training process, you'll get the trained model (foo.pb), label (foo.txt) and saved_model files from the result folder.

Verify the trained model

Verify the model with label_image.py, which comes from the official tensorflow repository, and we only changed the default settings so we don't have to type too many parameters. Check out the original folder here for label_image.py

Execute the label_image.py:

python label_image.py

And you should see the output something like:

r2d2 0.99754924
bb8 0.0024507595

Convert trained model to TFLite format

• There is an official link of Tensorflow TFLite: Introduction to TensorFlow Lite

For the trained data, we can easily use tflite_convert command like this:

tflite_convert --output_file=result/foo.tflite --input_format=TENSORFLOW_GRAPHDEF --output_format=TFLITE --input_array=Placeholder --output_array=final_result --inference_type=FLOAT --input_data_type=FLOAT --graph_def_file=result/foo.pb