How to use the SageMaker Image Classification - TensorFlow algorithm - Amazon SageMaker

How to use the SageMaker Image Classification - TensorFlow algorithm

You can use Image Classification - TensorFlow as an Amazon SageMaker built-in algorithm. The following section describes how to use Image Classification - TensorFlow with the SageMaker Python SDK. For information on how to use Image Classification - TensorFlow from the Amazon SageMaker Studio Classic UI, see SageMaker JumpStart pretrained models.

The Image Classification - TensorFlow algorithm supports transfer learning using any of the compatible pretrained TensorFlow Hub models. For a list of all available pretrained models, see TensorFlow Hub Models. Every pretrained model has a unique model_id. The following example uses MobileNet V2 1.00 224 (model_id: tensorflow-ic-imagenet-mobilenet-v2-100-224-classification-4) to fine-tune on a custom dataset. The pretrained models are all pre-downloaded from the TensorFlow Hub and stored in Amazon S3 buckets so that training jobs can run in network isolation. Use these pre-generated model training artifacts to construct a SageMaker Estimator.

First, retrieve the Docker image URI, training script URI, and pretrained model URI. Then, change the hyperparameters as you see fit. You can see a Python dictionary of all available hyperparameters and their default values with hyperparameters.retrieve_default. For more information, see Image Classification - TensorFlow Hyperparameters. Use these values to construct a SageMaker Estimator.

Note

Default hyperparameter values are different for different models. For larger models, the default batch size is smaller and the train_only_top_layer hyperparameter is set to "True".

This example uses the tf_flowers dataset, which contains five classes of flower images. We pre-downloaded the dataset from TensorFlow under the Apache 2.0 license and made it available with Amazon S3. To fine-tune your model, call .fit using the Amazon S3 location of your training dataset.

from sagemaker import image_uris, model_uris, script_uris, hyperparameters from sagemaker.estimator import Estimator model_id, model_version = "tensorflow-ic-imagenet-mobilenet-v2-100-224-classification-4", "*" training_instance_type = "ml.p3.2xlarge" # Retrieve the Docker image train_image_uri = image_uris.retrieve(model_id=model_id,model_version=model_version,image_scope="training",instance_type=training_instance_type,region=None,framework=None) # Retrieve the training script train_source_uri = script_uris.retrieve(model_id=model_id, model_version=model_version, script_scope="training") # Retrieve the pretrained model tarball for transfer learning train_model_uri = model_uris.retrieve(model_id=model_id, model_version=model_version, model_scope="training") # Retrieve the default hyper-parameters for fine-tuning the model hyperparameters = hyperparameters.retrieve_default(model_id=model_id, model_version=model_version) # [Optional] Override default hyperparameters with custom values hyperparameters["epochs"] = "5" # The sample training data is available in the following S3 bucket training_data_bucket = f"jumpstart-cache-prod-{aws_region}" training_data_prefix = "training-datasets/tf_flowers/" training_dataset_s3_path = f"s3://{training_data_bucket}/{training_data_prefix}" output_bucket = sess.default_bucket() output_prefix = "jumpstart-example-ic-training" s3_output_location = f"s3://{output_bucket}/{output_prefix}/output" # Create SageMaker Estimator instance tf_ic_estimator = Estimator( role=aws_role, image_uri=train_image_uri, source_dir=train_source_uri, model_uri=train_model_uri, entry_point="transfer_learning.py", instance_count=1, instance_type=training_instance_type, max_run=360000, hyperparameters=hyperparameters, output_path=s3_output_location, ) # Use S3 path of the training data to launch SageMaker TrainingJob tf_ic_estimator.fit({"training": training_dataset_s3_path}, logs=True)