Loading multiple saved tensorflow/keras models for prediction - tensorflow

I am trying to use multiple saved TensorFlow/Keras models for prediction.
My understanding is that I can create multiple models by simply loading different saved models.
saved_models_with_weights=[]
for model_path in paths:
saved_models_with_weights.append(keras.models.load_model(model_path))
And for prediction, I can simply iterate through these and get the prediction.
However, I read that Keras has a shared global namespace, and these will result in the wrong prediction.
When I tried the suggested solutions, I get compilation issues like
AttributeError: module 'tensorflow' has no attribute 'get_default_graph'
The above error is because in TF 2.0+ it is not available.
My question is related to the way I am loading multiple models.
Is this still an issue with TF 2.0+?

Related

Can't manage to open TensorFlow SavedModel for usage in Keras

I'm kinda new to TensorFlow and Keras, so please excuse any accidental stupidity, but I have an issue. I've been trying to load in models from the TensorFlow Detection Zoo, but haven't had much success.
I can't figure out how to read these saved_model folders (they contain a saved_model.pb file, and an assets and variables folder), so that they're accepted by Keras. Nor can I figure out a way to convert these models so that they may be loaded in. I've tried converting the SavedModel to ONNX, and then convert the ONNX-model to Keras, but that didn't work. Trying to load the original model as a saved_model, and then trying to to save this loaded model in another format gave me no success either.
Since you are new to Tensorflow (and I guess deep learning) I would suggest you stick with the API because the detection zoo models best interface with the object detection API. If you have already downloaded the model, you just need to export it using the exporter_main_v2.py script. This article explains it very well link.

How to convert a tensorflow hub pretrained model as to be consumable by tensorflow serving

I am trying to use this for my object detection task. The problems I am facing are:
On running the saved_model_cli command, I am getting the following output. There is no signature defined with tag-set "serve" also the method name is empty
The variable folder in the model directory only contains a few bytes of data which means the weights are not actually written to disk.
The model format seems to be HubModule V1 which seems to be the issue, any tips on making the above model servable are highly appreciated.
TF2 SavedModels should not have this problem, only Hub.Modules from TF1 since Hub.Modules use the signatures for other purposes. You can take a hub.Module and build a servable SavedModel, but it's quite complex and involves building the signatures yourself.
Instead, I recommend checking out the list of TF2 object detection models on TFHub.dev for a model you can use instead of the model you are using: https://tfhub.dev/s?module-type=image-object-detection&tf-version=tf2
These models should be servable with TF Serving

How to load tf.keras models with keras

I've been using the keras module from tensorflow 1.12.0 for training and saving models. I recently came across a seemingly useful library for visualization of the weights/outputs, but they require the models be loaded as a Keras model. I'm running into an error trying to load my tf.keras models using keras, and was hoping someone could provide a solution. Python version 3.5.2, Keras version 2.2.4.
I've defined the custom object for the GlorotUniform since keras doesn't recognize that initializer. Afterwards, when I try to load the model, I get a TypeError.
# This works
model = tf.keras.models.load_model('./densenet_model.h5')
# This does not work
model = keras.models.load_model('./densenet_model.h5', custom_objects={"GlorotUniform": tf.keras.initializers.glorot_uniform})
# This is the error that happens
TypeError: tuple indices must be integers or slices, not list
In summary, I was wondering if there was a simple way to convert a model created with tf.keras to a keras model.
I figured out a workaround. I just load the model with tf.keras.load_model, then save_weights. Then I build the same model with Keras and just use load_weights. I verified that the weights were loaded appropriately by checking the output with my validation dataset.
Instead of from keras.models import load_model I used from tensorflow.python.keras.models import load_model. The problem is solved.

Using TensorFlow object detection API models at prediction

I have used the TensorFlow object detection API to train the SSD Inception model from scratch. The evaluation script shows that the model has learned something and now I want to use the model.
I have looked at the object detection ipynb that can feed single images to a trained model. However, this is for SSD with MobileNet. I have used the following line (after loading the meta graph) to print the tensor names of the TensorFlow model I trained.
print([str(op.name) for op in tf.get_default_graph().get_operations()] )
But it does not contain the same input or output tensor names as in the ipynb. I have also searched through the code, but many functions point toward each other and it is difficult to find what I am looking for.
How can I find the tensor names I need? Or is there another method I do not know about?
To use the graph, you need to freeze/export it, using this provided script. The resulting .pb file will contain the nodes you need. I don't know why it's organized like that, but it is.

Exporting graphdef protobuf during training of inception model

Has anyone incorporated the ability to save a graphdef protobuf along with each checkpoint in the inception-v3 model?
Lively discussions at https://github.com/tensorflow/tensorflow/issues/616 provided some solutions to export graph protobufs, but I cannot get any of them working using the inception training model (inception_train.py).
I am trying to implement graph.util.convery_variables_to_constants, but I am failing to capture trainable variables, as I always get assertion errors: [variable] is not in graph. I am using output names from tensorboard, which may be incorrect procedure.
Any solutions to this issue would definitely be of interest to the general community, not only for learning but deployment.
Thanks!