I am training a stacked LSTM to classify text into a collection of different labels using Tensorflow Keras, but I am running into an odd issue regarding training. output after trying to train
I am not sure why the code runs without error, yet the model has not been trained. Furthermore, when I try to evaluate the model, test_loss, test_acc = model.evaluate(val_ds), I get name 'model' is not defined .
Not sure why this is happening. Any suggestions? The link to the file is https://github.com/tkowalski9938/Maureen-Crops.-Message-Predictor/blob/master/model.ipynb . Thanks for the help
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im quite new to object detection but i managed to train my first Tensorflow custom model yesterday. I think it worked fine besides some warnings, at least i got my exported_model folder with checkpoint, saved model and pipeline.config. I built it with exporter_main_v2.py from Tensorflow. I just loaded some images of deers and want to try to detect some on different pictures.
That's what i would like to test now, but i dont know how. I already did an object detection tutorial with pre trained models and it worked fine. I tried to just replace config_file_path, saved_model_path and image_path with the paths linking to my exported model but it didnt work:
error: OpenCV(4.6.0) D:\a\opencv-python\opencv-python\opencv\modules\dnn\src\tensorflow\tf_io.cpp:42: error: (-2:Unspecified error) FAILED: ReadProtoFromBinaryFile(param_file, param). Failed to parse GraphDef file: D:\VSCode\Machine_Learning_Tests\Tensorflow\workspace\exported_models\first_model\saved_model\saved_model.pb in function 'cv::dnn::ReadTFNetParamsFromBinaryFileOrDie'
There are endless tutorials on how to train custom detection but i cant find a good explanation how to manually test my exported model.
Thanks in advance!
EDIT: I need to know how to build a script where i can import a model i saved with Tensorflow exporter_main_v2.py and an image i want to test this model on and get a result, either in text or with rectangels in picture. Seeing many tutorials but none works for me with a model i saved with Tensorflow exporter_main_v2.py
From the error it looks like you have a model saved as .pb. If you want to do inference you can write something like this:
# load the model
model = tf.keras.models.load_model(my_model_dir)
prediction = model.predict(x=x_test, ...)
You'll have to set x which is the only mandatory argument. It is your test dataset (the images you want to obtain predictions from). Also, predict is useful when you have a great amount of images to predict. It handles the prediction in a batched way, avoiding filling up the memory. If you have just a few you can use directly the __call__() method of your model, like this:
prediction = model(x_test, training=False)
More about prediction can be found at the Tensorflow documentation.
I am using a custom keras model in Databricks environment.
For a custom keras model, model.save(model.h5) does not work, because custom model is not serializable. Instead it is recommended to use model.save_weights(path) as an alternate.
model.save_weights(pathDirectory) works. This yields 3 files checkpoint,.data-00000-of-00001,.index in the pathDirectory
For loading weights, Following mechanism is working fine.
model = Model()
model.load_weights(path)
But I want to train my model on pretrained weights I just saved. Like I saved model weights, and continue training on these saved weights afterwards.
So, when I load model weights and apply training loop, I get this error, TypeError: 'CheckpointLoadStatus' object is not callable
After much research, I have found a workaround,
we can also save model using
model.save("model.hpy5") and read it the saved model in databricks.
model.h5 not work for customized models, but it works for standard models.
There are many examples about how to do fine-tuning with tensorflow. Almost all these examples are try to resize our images to the specified size that the existing model needs. Like for example, 224×224 is the input size that vgg19 needs. However, in keras, we can change the input size by setting the include_top to false:
base_model = VGG19(include_top=False, weights="imagenet", input_shape=(input_size, input_size, input_channels))
Then we do not have to fix the image size to be 224×224 anymore. Can we do such kind of fine-tuning by using official pre-trained models in tensorflow? I cannot find the solutions up till now, anyone help me?
Yes, it is possible to do this kind of fine-tuning. You would just have to ensure that you also fine-tune some of the first few layers (to account for changed input) of the original network in addition to the last few layers (to account for changed output).
I work with TensorFlow using Keras. If you are open to that, then there is a code snippet that shows the general fine-tuning flow here:
https://keras.io/applications/
Specifically, I had to write the following code to make it work for my case:
#img_width,img_height is the size of your new input, 3 is the number of channels
input_tensor = Input(shape=(img_width, img_height, 3))
base_model =
keras.applications.vgg19.VGG19(include_top=False,weights='imagenet', input_tensor=input_tensor)
#instantiate whatever other layers you need
model = Model(inputs=base_model.inputs, outputs=predictions)
#predictions is the new logistic layer added to account for new classes
Hope this helps.
I am new to TensorFlow and I am just trying to see if my idea is even possible.
I have trained a model with multi class classifier. Now I can classify a sentence in input, but I would like to change the result of CNN, for example, to improve the score of classification or change the classification.
I want to try to train just a single sentence with its class on a trained model, is this possible?
If I understand your question correctly, you are trying to reload a previously trained model either to run it through further iterations, test it on a new sentence, or fine tune the model a bit. If this is the case, yes you can do this. Look into saving and restoring models (https://www.tensorflow.org/api_guides/python/state_ops#Saving_and_Restoring_Variables).
To give you a rough outline, when you initially train your model, after setting up the network architecture, set up a saver:
trainable_var = tf.trainable_variables()
sess = tf.Session()
saver = tf.train.Saver()
sess.run(tf.global_variables_initializer
# Run/train your model until some completion criteria is reached
#....
#....
saver.save(sess, 'model.ckpt')
Now, to reload your model:
saver = tf.train.import_meta_graph('model.ckpt.meta')
saver.restore('model.ckpt')
#Note: if you have already defined all variables before restoring the model, import_meta_graph is not necessary
This will give you access to all the trained variables and you can now feed in whatever new sentence you have. Hope this helps.
In classify_image.py, the input image is fed with a loaded image in
predictions = sess.run(softmax_tensor,{'DecodeJpeg/contents:0': image_data})
What if I want to add new layers to the inception model and train the whole model again? Are the variables loaded from classify_image_graph_def.pb trainable? I saw that freeze_graph.py used convert_variables_to_constants to produce freezed graph. So can those loaded weights be trained again, are they constants? And how can I connect the input('shuffle_batch:0') to the inception model to the output of tf.train.shuffle_batch?
The model used in classify_image.py has its variables frozen into constants, and doesn't have any gradient ops, so it's not easy to turn it back into something trainable. You can see how we remove one layer and replace it with something trainable here:
https://github.com/tensorflow/tensorflow/blob/master/tensorflow/examples/image_retraining/retrain.py
It's hard to generalize though. You'd be better off looking at some examples of fine-tuning here:
https://github.com/tensorflow/models/tree/master/inception#how-to-fine-tune-a-pre-trained-model-on-a-new-task