simple element wise with Keras over TF - tensorflow

i am trying to implement the following in TensorFlow:
Input * const
matrix multiplication of 640x800x6
Here is the code
ssValues = np.zeros(shape=(6,640,800),dtype=np.float16)
inputPlaceHolder = tf.compat.v1.placeholder(shape=(6,640,800), name='InputTensor', dtype=tf.dtypes.float16)
inputLayer = tf.keras.Input(shape=(6,640,800,),
batch_size=1,
name='inputLayer',
dtype=tf.dtypes.float16,
tensor=inputPlaceHolder)
ssConstant = tf.constant(ssValues, dtype=tf.dtypes.float16, shape=(6,640,800), name='ss')
ssm = tf.keras.layers.Multiply()([inputPlaceHolder,inputPlaceHolder])
model = tf.keras.models.Model(inputs=inputLayer, outputs=ssm)
input = np.zeros(shape=(6,640,800),dtype=np.float16)
output = model.predict(input)
i get the following error:
ValueError: ('Error when checking model input: expected no data, but got:', array([[[1., 1., 1., ..., 1., 1., 1.],
how to overcome this error and run the predict function ?
why tf.keras.layers.multiply doesn't return a Layer object ?

Your issue comes from the fact that you declared your operation on a v1 placeholder, when it should simply use the inputLayer (which already acts as a placeholder for inputs following the provided specification).
Additionnally, you wrote a multiplication that returns $x \times x$, when I think you wanted $x \times constant$ ; so here would be the code:
inputLayer = tf.keras.Input(shape=(6,640,800,),
batch_size=1,
name='inputLayer',
dtype=tf.dtypes.float16)
ssConstant = tf.constant( # also fixed a shape issue here
ssValues, dtype=tf.dtypes.float16, shape=(1, 6,640,800), name='ss'
)
ssm = tf.keras.layers.Multiply(dtype=tf.dtypes.float16)([inputLayer, ssConstant])
model = tf.keras.models.Model(inputs=inputLayer, outputs=ssm)
inputs = np.zeros(shape=(1,6,640,800), dtype=np.float16)
output = model.predict(inputs)
Furthermore, since this is not an actual model, in the sense that it uses a constant and not learnable weights, you might want to use tf.keras.backend.function instead of tf.keras.Model (but that is really up to you).
Note that the shapes are probably not suited to what you actually want, with the batch-size of 1... Please consider using a batch-size of 6 to remove the useless dimensions.

When you use Input(shape) you have a placeholder already. It doesn't make sense to create a placeholder to the pass it to Input(tensor=placeholder) because this is not how Keras works.
You must:
inputs = Input(shape=(6,640,800))
ssm_tensor = Multiply()([inputs, inputs])
model = Model(inputs, ssm)
Since you always have a batch size with Keras:
input = np.zeros(shape=(1,6,640,800))

Related

convert tf.dense Tensor to tf.one_hot Tensor on Graph execution Tensorflow

TF version: 2.11
I try to train a simple 2input classifier with TFRecords tf.data pipeline
I do not manage to convert the tf.dense Tensor with containing only a scalar to a tf.onehot vector
# get all recorddatasets abspath
training_names= [record_path+'/'+rec for rec in os.listdir(record_path) if rec.startswith('train')]
# load in tf dataset
train_dataset = tf.data.TFRecordDataset(training_names[1])
train_dataset = train_dataset.map(return_xy)
mapping function:
def return_xy(example_proto):
#parse example
sample= parse_function(example_proto)
#decode image 1
encoded_image1 = sample['image/encoded_1']
decoded_image1 = decode_image(encoded_image1)
#decode image 2
encoded_image2 = sample['image/encoded_2']
decoded_image2 = decode_image(encoded_image2)
#decode label
print(f'image/object/class/'+level: {sample['image/object/class/'+level]}')
class_label = tf.sparse.to_dense(sample['image/object/class/'+level])
print(f'type of class label :{type(class_label)}')
print(class_label)
# conversion to onehot with depth 26 :: -> how can i extract only the value or convert directly to tf.onehot??
label_onehot=tf.one_hot(class_label,26)
#resizing image
input_left=tf.image.resize(decoded_image1,[416, 416])
input_right=tf.image.resize(decoded_image2,[416, 416])
return {'input_3res1':input_left, 'input_5res2':input_right} , label_onehot
output:
image/object/class/'+level: SparseTensor(indices=Tensor("ParseSingleExample/ParseExample/ParseExampleV2:14", shape=(None, 1), dtype=int64), values=Tensor("ParseSingleExample/ParseExample/ParseExampleV2:31", shape=(None,), dtype=int64), dense_shape=Tensor("ParseSingleExample/ParseExample/ParseExampleV2:48", shape=(1,), dtype=int64))
type of class label :<class 'tensorflow.python.framework.ops.Tensor'>
Tensor("SparseToDense:0", shape=(None,), dtype=int64)
However I am sure that the label is in this Tensor because when run it eagerly
raw_dataset = tf.data.TFRecordDataset([rec_file])
parsed_dataset = raw_dataset.map(parse_function) # only parsing
for sample in parsed_dataset:
class_label=tf.sparse.to_dense(sample['image/object/class/label_level3'])[0]
print(f'type of class label :{type(class_label)}')
print(f'labels from labelmap :{class_label}')
I get output:
type of class label :<class 'tensorflow.python.framework.ops.EagerTensor'>
labels from labelmap :7
If I just chose a random number for the label and pass it to tf_one_hot(randint, 26) then the model begins to train (obviously nonsensical).
So the question is how can i convert the:
Tensor("SparseToDense:0", shape=(None,), dtype=int64)
to a
Tensor("one_hot:0", shape=(26,), dtype=float32)
What I tried so far
in the call data.map(parse_xy)
i tried to just call .numpy() on the tf tensors but didnt work , this only works for eager tensors.
In my understanding i cannot use eager execution because everthing in the parse_xy function gets excecuted on the whole graph:
ive already tried to enable eager execution -> failed
https://www.tensorflow.org/api_docs/python/tf/config/run_functions_eagerly
Note: This flag has no effect on functions passed into tf.data transformations as arguments.
tf.data functions are never executed eagerly and are always executed as a compiled Tensorflow Graph.
ive also tried to use the tf_pyfunc but this only returns another tf.Tensor with an unknown shape
def get_onehot(tensor):
class_label=tensor[0]
return tf.one_hot(class_label,26)
and add the line in parse_xy:
label_onehot=tf.py_function(func=get_onehot, inp=[class_label], Tout=tf.int64)
but there i always get an unknown shape which a cannot just alter with .set_shape()
I was able to solve the issue by only using TensorFlow functions.
tf.gather allows to index a TensorFlow tensor:
class_label_gather = tf.sparse.to_dense(sample['image/object/class/'+level])
class_indices = tf.gather(tf.cast(class_label_gather,dtype=tf.int32),0)
label_onehot=tf.one_hot(class_indices,26)

How to get vocabulary size in tensorflow_transform before apply_vocabulary?

Also posted the question at https://github.com/tensorflow/transform/issues/261
I am using tft in TFX and needs to transform string list class labels into multi-hot indicators inside preprocesing_fn. Essentially:
vocab = tft.vocabulary(inputs['label'])
outputs['label'] = tf.cast(
tf.sparse.to_indicator(
tft.apply_vocabulary(inputs['label'], vocab),
vocab_size=VOCAB_SIZE,
),
"int64",
)
I am trying to get VOCAB_SIZE from the result of vocab, but couldn't find a way to satisfy the deferred execution and known shapes. The closest I got below wouldn't pass the saved model export as the shape for label is unknown.
def _make_table_initializer(filename_tensor):
return tf.lookup.TextFileInitializer(
filename=filename_tensor,
key_dtype=tf.string,
key_index=tf.lookup.TextFileIndex.WHOLE_LINE,
value_dtype=tf.int64,
value_index=tf.lookup.TextFileIndex.LINE_NUMBER,
)
def _vocab_size(deferred_vocab_filename_tensor):
initializer = _make_table_initializer(deferred_vocab_filename_tensor)
table = tf.lookup.StaticHashTable(initializer, default_value=-1)
table_size = table.size()
return table_size
deferred_vocab_and_filename = tft.vocabulary(inputs['label'])
vocab_applied = tft.apply_vocabulary(inputs['label'], deferred_vocab_and_filename)
vocab_size = _vocab_size(deferred_vocab_and_filename)
outputs['label'] = tf.cast(
tf.sparse.to_indicator(vocab_applied, vocab_size=vocab_size),
"int64",
)
Got
ValueError: Feature label (Tensor("Identity_3:0", shape=(None, None), dtype=int64)) had invalid shape (None, None) for FixedLenFeature: apart from the batch dimension, all dimensions must have known size [while running 'Analyze/CreateSavedModel[tf_v2_only]/CreateSavedModel']
Any idea how to achieve this?
As per this comment in the github issue, You can use tft.experimental.get_vocabulary_size_by_name (link) to achieve the same.

Performing inference with a BERT (TF 1.x) saved model

I'm stuck on one line of code and have been stalled on a project all weekend as a result.
I am working on a project that uses BERT for sentence classification. I have successfully trained the model, and I can test the results using the example code from run_classifier.py.
I can export the model using this example code (which has been reposted repeatedly, so I believe that it's right for this model):
def export(self):
def serving_input_fn():
label_ids = tf.placeholder(tf.int32, [None], name='label_ids')
input_ids = tf.placeholder(tf.int32, [None, self.max_seq_length], name='input_ids')
input_mask = tf.placeholder(tf.int32, [None, self.max_seq_length], name='input_mask')
segment_ids = tf.placeholder(tf.int32, [None, self.max_seq_length], name='segment_ids')
input_fn = tf.estimator.export.build_raw_serving_input_receiver_fn({
'label_ids': label_ids, 'input_ids': input_ids,
'input_mask': input_mask, 'segment_ids': segment_ids})()
return input_fn
self.estimator._export_to_tpu = False
self.estimator.export_savedmodel(self.output_dir, serving_input_fn)
I can also load the exported estimator (where the export function saves the exported model into a subdirectory labeled with a timestamp):
predict_fn = predictor.from_saved_model(self.output_dir + timestamp_number)
However, for the life of me, I cannot figure out what to provide to predict_fn as input for inference. Here is my best code at the moment:
def predict(self):
input = 'Test input'
guid = 'predict-0'
text_a = tokenization.convert_to_unicode(input)
label = self.label_list[0]
examples = [InputExample(guid=guid, text_a=text_a, text_b=None, label=label)]
features = convert_examples_to_features(examples, self.label_list,
self.max_seq_length, self.tokenizer)
predict_input_fn = input_fn_builder(features, self.max_seq_length, False)
predict_fn = predictor.from_saved_model(self.output_dir + timestamp_number)
result = predict_fn(predict_input_fn) # this generates an error
print(result)
It doesn't seem to matter what I provide to predict_fn: the examples array, the features array, the predict_input_fn function. Clearly, predict_fn wants a dictionary of some type - but every single thing that I've tried generates an exception due to a tensor mismatch or other errors that generally mean: bad input.
I presumed that the from_saved_model function wants the same sort of input as the model test function - apparently, that's not the case.
It seems that lots of people have asked this very question - "how do I use an exported BERT TensorFlow model for inference?" - and have gotten no answers:
Thread #1
Thread #2
Thread #3
Thread #4
Any help? Thanks in advance.
Thank you for this post. Your serving_input_fn was the piece I was missing! Your predict function needs to be changed to feed the features dict directly, rather than use the predict_input_fn:
def predict(sentences):
labels = [0, 1]
input_examples = [
run_classifier.InputExample(
guid="",
text_a = x,
text_b = None,
label = 0
) for x in sentences] # here, "" is just a dummy label
input_features = run_classifier.convert_examples_to_features(
input_examples, labels, MAX_SEQ_LEN, tokenizer
)
# this is where pred_input_fn is replaced
all_input_ids = []
all_input_mask = []
all_segment_ids = []
all_label_ids = []
for feature in input_features:
all_input_ids.append(feature.input_ids)
all_input_mask.append(feature.input_mask)
all_segment_ids.append(feature.segment_ids)
all_label_ids.append(feature.label_id)
pred_dict = {
'input_ids': all_input_ids,
'input_mask': all_input_mask,
'segment_ids': all_segment_ids,
'label_ids': all_label_ids
}
predict_fn = predictor.from_saved_model('../testing/1589418540')
result = predict_fn(pred_dict)
print(result)
pred_sentences = [
"That movie was absolutely awful",
"The acting was a bit lacking",
"The film was creative and surprising",
"Absolutely fantastic!",
]
predict(pred_sentences)
{'probabilities': array([[-0.3579178 , -1.2010787 ],
[-0.36648935, -1.1814401 ],
[-0.30407643, -1.3386648 ],
[-0.45970002, -0.9982413 ],
[-0.36113673, -1.1936386 ],
[-0.36672896, -1.1808994 ]], dtype=float32), 'labels': array([0, 0, 0, 0, 0, 0])}
However, the probabilities returned for sentences in pred_sentences do not match the probabilities I get use estimator.predict(predict_input_fn) where estimator is the fine-tuned model being used within the same (python) session. For example, [-0.27276006, -1.4324446 ] using estimator vs [-0.26713806, -1.4505868 ] using predictor.

How to use an optimizer within a forward pass in PyTorch

I want to use an optimizer within the forward pass of a custom defined Function, but it doesn't work. My code is as follows:
class MyFct(Function):
#staticmethod
def forward(ctx, *args):
input, weight, bias = args[0], args[1], args[2]
y = torch.tensor([[0]], dtype=torch.float, requires_grad=True) #initial guess
loss_fn = lambda y_star: (input + weight - y_star)**2
learning_rate = 1e-4
optimizer = torch.optim.Adam([y], lr=learning_rate)
for t in range(5000):
y_star = y
print(y_star)
loss = loss_fn(y_star)
if t % 100 == 99:
print(t, loss.item())
optimizer.zero_grad()
loss.backward()
optimizer.step()
return y_star
And that's my test inputs:
x = torch.tensor([[2]], dtype=torch.float, requires_grad=True)
w = torch.tensor([[2]], dtype=torch.float, requires_grad=True)
y = torch.tensor([[6]], dtype=torch.float)
fct= MyFct.apply
y_hat = fct(x, w, None)
I always get the RuntimeError: element 0 of tensors does not require grad and does not have a grad_fn.
Also, I've tested the optimization outside of the forward and it works, so I guess it's something with the context? According to the documentation "Tensor arguments that track history (i.e., with requires_grad=True) will be converted to ones that don’t track history before the call, and their use will be registered in the graph", see https://pytorch.org/docs/stable/notes/extending.html. Is this the problem? Is there a way to work around it?
I am new to PyTorch and I wonder what I'm overlooking. Any help and explanation is appreciated.
I think I found an answer here: https://github.com/pytorch/pytorch/issues/8847 , i.e. I need to wrap the oprimization with with torch.enable_grad():.
However, I still don't understand why it's necessary to convert the original Tensors to ones that don’t track history in forward().

how to merge 'Conv-BN-Scale' into a single 'Conv' layer for tensorflow?

For faster inference one model, I want to merge 'Conv-BN-Scale' into a single 'Conv' layer for my tensorflow model, but I can not find some useful complete example about how to do it?
Anyone can give some advises or complete code example?
Thanks!
To merge two layers, you will need to pass a Tensor and get a tensor back that is after both the layers are applied, suppose your input tensor is X.
def MlConvBnScale(X ,kernel,strides , padding = 'SAME' , scale = False, beta_initializer = 0.1, gamma_initializer = 0.1, moving_mean_initializer = 0.1, moving_variance_initializer = 0.1):
convLout = tf.nn.conv2d(X,
filter = Kernel,
strides = strides,
padding = padding)
return tf.nn.batch_normalization(convLout,
scale = scale,
beta_initializer = beta_initializer,
gamma_initializer = gamma_initializer,
moving_mean_initializer = moving_mean_intializer,
moving_variance_initializer = moving_variance_initializer )
And that will return a tensor after performing both the operations, I have taken default values of variables but you can modify them in your function call, and in case your input is not already a tensor but a numpy array you can use tf.convert_to_tensor() from this link https://www.tensorflow.org/api_docs/python/tf/convert_to_tensor, and in case you are struggling with kernel/filter and its application, check out this thread. What does tf.nn.conv2d do in tensorflow?
If you have any queries or run into trouble implementing it, comment down below and we will see.