running_locally.md

Running Locally

This page walks through the steps required to train an object detection model on a local machine. It assumes the reader has completed the following prerequisites:

1. The Tensorflow Object Detection API has been installed as documented in the installation instructions. This includes installing library dependencies, compiling the configuration protobufs and setting up the Python environment.
2. A valid data set has been created. See this page for instructions on how to generate a dataset for the PASCAL VOC challenge or the Oxford-IIIT Pet dataset.
3. A Object Detection pipeline configuration has been written. See this page for details on how to write a pipeline configuration.

Recommended Directory Structure for Training and Evaluation

+data
  -label_map file
  -train TFRecord file
  -eval TFRecord file
+models
  + model
    -pipeline config file
    +train
    +eval

Running the Training Job

A local training job can be run with the following command:

# From the tensorflow/models/ directory
python object_detection/train.py \
    --logtostderr \
    --pipeline_config_path=${PATH_TO_YOUR_PIPELINE_CONFIG} \
    --train_dir=${PATH_TO_TRAIN_DIR}

where ${PATH_TO_YOUR_PIPELINE_CONFIG} points to the pipeline config and ${PATH_TO_TRAIN_DIR} points to the directory in which training checkpoints and events will be written to. By default, the training job will run indefinitely until the user kills it.

Running the Evaluation Job

Evaluation is run as a separate job. The eval job will periodically poll the train directory for new checkpoints and evaluate them on a test dataset. The job can be run using the following command:

# From the tensorflow/models/ directory
python object_detection/eval.py \
    --logtostderr \
    --pipeline_config_path=${PATH_TO_YOUR_PIPELINE_CONFIG} \
    --checkpoint_dir=${PATH_TO_TRAIN_DIR} \
    --eval_dir=${PATH_TO_EVAL_DIR}

where ${PATH_TO_YOUR_PIPELINE_CONFIG} points to the pipeline config, ${PATH_TO_TRAIN_DIR} points to the directory in which training checkpoints were saved (same as the training job) and ${PATH_TO_EVAL_DIR} points to the directory in which evaluation events will be saved. As with the training job, the eval job run until terminated by default.

Running Tensorboard

Progress for training and eval jobs can be inspected using Tensorboard. If using the recommended directory structure, Tensorboard can be run using the following command:

tensorboard --logdir=${PATH_TO_MODEL_DIRECTORY}

where ${PATH_TO_MODEL_DIRECTORY} points to the directory that contains the train and eval directories. Please note it make take Tensorboard a couple minutes to populate with data.