pytorch model -> onnx -> tensorflow - tensorflow

I made pytorch model for machine learning and I want to convert this to tensorflow model. I think I converted pytorch model to onnx.
so now I want to convert onnx to tensorflow(pb) model.
Here is my code.
import onnx
from onnx_tf.backend import prepare
onnx_model = onnx.load("./sales_predict_model.onnx") # load onnx model
tf_rep = prepare(onnx_model) # prepare tf representation
tf_rep.export_graph("sales_predict_model.pb") # export the model
And I got error here.
AssertionError: Tried to export a function which references untracked object Tensor("1076:0", shape=(), dtype=resource)`.
TensorFlow objects (e.g. `tf.Variable`) captured by functions must be tracked by assigning them to an attribute of a tracked object or assigned to an attribute of the main object directly.
I am using TensorFlow version 1.14.0.
Maybe Onnx version 1.7.0 (I checked this pip show onnx)
onnx-tf version 1.6.0 (pip show onnx-tf)
Here is the code below when I converted pytorch model to ONNX.
class LSTM(nn.Module):
def __init__(self, input_dim, hidden_dim, num_layers, output_dim):
super(LSTM, self).__init__()
self.hidden_dim = hidden_dim
self.num_layers = num_layers
self.lstm = nn.LSTM(input_dim, hidden_dim, num_layers, batch_first=True)
self.fc = nn.Linear(hidden_dim, output_dim)
def forward(self, x):
h0 = torch.zeros(self.num_layers, x.size(0), self.hidden_dim).requires_grad_()
c0 = torch.zeros(self.num_layers, x.size(0), self.hidden_dim).requires_grad_()
x = torch.tensor(x, dtype = torch.float32)
out, (hn, cn) = self.lstm(x, (h0.detach(), c0.detach()))
out, (hn, cn) = self.lstm(x, (h0.detach(), c0.detach()))
out = out[:, -1, :]
out = self.fc(out)
return out
PATH = './model/file300input5lb1ep100drop0W_V7'
model = torch.load(PATH + 'model.pt')
model.eval()
x = torch.randn(1, 1, 5, requires_grad=True)
torch_out = model(x)
torch.onnx.export(model,
x,
"sales_predict_model.onnx",
export_params=True,
opset_version=10,
do_constant_folding=True,
input_names = ['input'],
output_names = ['x'],
dynamic_axes={'input' : {0 : 'batch_size'},
'output' : {0 : 'batch_size'}})

Related

Unexpected input data type. Actual: (tensor(double)) , expected: (tensor(float))

I am learning this new ONNX framework that allows us to deploy the deep learning (and others) model into production.
However, there is one thing I am missing. I thought that the main reason for having such a framework is so that for inference purposes e.g. when we have a trained model and want to use it in a different venv (where for example we cannot have PyTorch) the model still can be used.
I have preped a "from scratch" example here:
# Modules
import torch
import torch.nn as nn
import torch.optim as optim
import torch.nn.functional as F
from torch.utils.data import DataLoader, TensorDataset
import torchvision
import onnx
import onnxruntime
import matplotlib.pyplot as plt
import numpy as np
# %config Completer.use_jedi = False
# MNIST Example dataset
train_loader = torch.utils.data.DataLoader(
torchvision.datasets.MNIST(
'data', train=True, download=True,
transform=torchvision.transforms.Compose([
torchvision.transforms.ToTensor(),
])),
batch_size=800)
# Take data and labels "by hand"
inputs_batch, labels_batch = next(iter(train_loader))
# Simple Model
class CNN(nn.Module):
def __init__(self, in_channels, num_classes):
super(CNN, self).__init__()
self.conv1 = nn.Conv2d(in_channels=in_channels,
out_channels = 10, kernel_size = (3, 3), stride = (1, 1), padding=(1, 1))
self.pool = nn.MaxPool2d(kernel_size=(2, 2), stride = (2, 2))
self.conv2 = nn.Conv2d(in_channels = 10, out_channels=16, kernel_size = (3, 3), stride = (1, 1), padding=(1, 1))
self.fc1 = nn.Linear(16*7*7, num_classes)
def forward(self, x):
x = F.relu(self.conv1(x))
x = self.pool(x)
x = F.relu(self.conv2(x))
x = self.pool(x)
x = x.reshape(x.shape[0], -1)
x = self.fc1(x)
return x
# Training setting
device = 'cpu'
batch_size = 64
learning_rate = 0.001
n_epochs = 10
# Dataset prep
dataset = TensorDataset(inputs_batch, labels_batch)
TRAIN_DF = DataLoader(dataset = dataset, batch_size = batch_size, shuffle = True)
# Model Init
model = CNN(in_channels=1, num_classes=10)
optimizer = optim.Adam(model.parameters(), lr = learning_rate)
# Training Loop
for epoch in range(n_epochs):
for data, labels in TRAIN_DF:
model.train()
# Send Data to GPU
data = data.to(device)
# Send Data to GPU
labels = labels.to(device)
# data = data.reshape(data.shape[0], -1)
# Forward
pred = model(data)
loss = F.cross_entropy(pred, labels)
# Backward
optimizer.zero_grad()
loss.backward()
optimizer.step()
# Check Accuracy
def check_accuracy(loader, model):
num_correct = 0
num_total = 0
model.eval()
with torch.no_grad():
for x, y in loader:
x = x.to(device)
y = y.to(device)
# x = x.reshape(x.shape[0], -1)
scores = model(x)
_, pred = scores.max(1)
num_correct += (pred == y).sum()
num_total += pred.size(0)
print(F"Got {num_correct} / {num_total} with accuracy {float(num_correct)/float(num_total)*100: .2f}")
check_accuracy(TRAIN_DF, model)
# Inference with ONNX
# Create Artifical data of the same size
img_size = 28
dummy_data = torch.randn(1, img_size, img_size)
dummy_input = torch.autograd.Variable(dummy_data).unsqueeze(0)
input_name = "input"
output_name = "output"
model_eval = model.eval()
torch.onnx.export(
model_eval,
dummy_input,
"model_CNN.onnx",
input_names=["input"],
output_names=["output"],
)
# Take Random Image from Training Data
X_pred = data[4].unsqueeze(0)
# Convert the Tensor image to PURE numpy and pretend we are working in venv where we only have numpy - NO PYTORCH
X_pred_np = X_pred.numpy()
X_pred_np = np.array(X_pred_np)
IMG_Rando = np.random.rand(1, 1, 28, 28)
np.shape(X_pred_np) == np.shape(IMG_Rando)
ort_session = onnxruntime.InferenceSession(
"model_CNN.onnx"
)
def to_numpy(tensor):
return (
tensor.detach().gpu().numpy()
if tensor.requires_grad
else tensor.cpu().numpy()
)
# compute ONNX Runtime output prediction
# WORKS
# ort_inputs = {ort_session.get_inputs()[0].name: X_pred_np}
# DOES NOT WORK
ort_inputs = {ort_session.get_inputs()[0].name: IMG_Rando}
# WORKS
# ort_inputs = {ort_session.get_inputs()[0].name: to_numpy(X_pred)}
ort_outs = ort_session.run(None, ort_inputs)
ort_outs
Firstly, we create a simple model and train it on the MNIST dataset.
Then we export the trained model using the ONNX framework.
Now, when I want to classify an image using the X_pred_np It works even though it is a "pure" NumPy, which is what I want.
However, I suspect that this particular case works only because it has been derived from the PyTorch tensor object, and thus "under the hood" it still has PyTorch attributes.
While when I try to inference on the random "pure" NumPy object IMG_Rando, there seems to be a problem:
Unexpected input data type. Actual: (tensor(double)) , expected: (tensor(float)).
Referring that PyTorch form is needed.
Is there a way how to be able to use only numpy Images for the ONNX predictions?. So the inference can be performed in separated venv where no pytorch is installed?
Secondly, is there a way that ONNX would remember the actual classes?
In this particular case, the index corresponds to the label of the image. However, in animal classification, ONNX would not provide us with the "DOG" and "CAT" and other labels but would only provide us the index of the predicted label. Which we would need to run throw our own "prediction dictionary" so we know that the fifth label is associated with "cat" and sixth label is associated with "dog" etc.
Numpy defaults to float64 while pytorch defaults to float32. Cast the input to float32 before the inference:
IMG_Rando = np.random.rand(1, 1, 28, 28).astype(np.float32)
double is short for double-precision floating-point format, which is a floating point number representation on 64 bits, while float refers to a floating point number on 32 bits.
As an improvement to the accepted answer, the idiomatic way to generate random numbers in Numpy is now by using a Generator. This offers the benefit of being able to create the array in the right type directly, rather than using the expensive astype operation, which copies the array (as in the accepted answer). Thus, the improved solution would look like:
rng = np.random.default_rng() # set seed if desired
IMG_Rando = rng.random((1, 1, 28, 28), dtype=np.float32)

Tensor format issue from converting Pytorch -> Onnx -> Tensorflow

I have an issue with Tensorflow model that is converted from Pytorch -> Onnx -> Tensorflow. The issue is the converted Tensorflow model expects the input in Pytorch format that is (batch size, number channels, height, width) but not in Tensorflow format (batch size, height, width, number channel). Therefore, I cannot use the model to process further with Vitis AI.
So I would like to ask is there is any ways to convert this Pytorch input format to Tensorflow format by using tools from Onnx, Tensorflow 1, or others?
My code is as below:
Pytorch -> Onnx
from hardnet import hardnet
import torch
import onnx
ckpt = torch.load('../hardnet.pth')
model_state_dict = ckpt['model_state_dict']
optimizer_state_dict = ckpt['optimizer_state_dict']
model = hardnet(11)
model.load_state_dict(model_state_dict)
model.eval()
dummy_input = torch.randn(1, 3, 1080, 1920)
input_names = ['input0']
output_names = ['output0']
output_file = 'hardnet.onnx'
torch.onnx.export(model, dummy_input, output_file, verbose=True,
input_names=input_names, output_names=output_names,
opset_version=11, keep_initializers_as_inputs=True)
onnx_model = onnx.load(output_file)
onnx.checker.check_model(onnx_model)
print('Passed Onnx')
Onnx -> Tensorflow 1 (using Tensorflow 1.15)
import cv2
import numpy as np
import tensorflow as tf
import matplotlib.pyplot as plt
import onnx
from onnx_tf.backend import prepare
output_file = 'hardnet.onnx'
onnx_model = onnx.load(output_file)
output = prepare(onnx_model)
output.export_graph('hardnet.pb')
tf.compat.v1.disable_eager_execution()
def load_pb(path_to_pb: str):
"""From: https://stackoverflow.com/questions/51278213/what-is-the-use-of-a-pb-file-in-tensorflow-and-how-does-it-work
"""
with tf.gfile.GFile(path_to_pb, "rb") as f:
graph_def = tf.GraphDef()
graph_def.ParseFromString(f.read())
with tf.Graph().as_default() as graph:
tf.import_graph_def(graph_def, name='')
return graph
graph = load_pb('hardnet.pb')
input = graph.get_tensor_by_name('input0:0')
output = graph.get_tensor_by_name('output0:0')
mean = [0.485, 0.456, 0.406]
std = [0.229, 0.224, 0.225]
img = cv2.imread('train_0.jpg', cv2.IMREAD_COLOR)
img = cv2.resize(img, (1920, 1080))
img = img/255
img = img - mean
img = img/std
img = np.expand_dims(img, -1)
# To Pytorch format.
img = np.transpose(img, (3, 2, 0, 1))
img = img
with tf.Session(graph=graph) as sess:
pred = sess.run(output, {input: img})
You could wrap your Pytorch model into another one that would do the transpose you want to have in TensorFlow. See the following example:
Let's say you have the following toy NN:
class Net(nn.Module):
def __init__(self):
super(Net, self).__init__()
self.rnn = nn.LSTM(10, 20, 2)
def forward(self, x):
h0 = torch.zeros(2, 3, 20)
c0 = torch.zeros(2, 3, 20)
return self.rnn(x, (h0, c0))
the exemplary pytorch/tensorflow input shape would be :
>> pytorch_input = torch.randn(5, 3, 10)
>> tf_input = torch.transpose(pytorch_input, 1, 2)
>> print("PyTorch input shape: ", pytorch_input.shape)
>> print("TensorFlow input shape: ", tf_input.shape)
PyTorch input shape: torch.Size([5, 3, 10])
TensorFlow input shape: torch.Size([5, 10, 3])
Now, the wrapper which will first transpose input and then pass transposed input to some model:
class NetTensorFlowWrapper(nn.Module):
def __init__(self, main_module: nn.Module):
super(NetTensorFlowWrapper, self).__init__()
self.main_module = main_module
def forward(self, x):
x = torch.transpose(x, 1, 2)
return self.main_module(x)
Then, this is possible:
net = Net()
net_wrapper = NetTensorFlowWrapper(net)
net(pytorch_input)
net_wrapper(tf_input)
and then, when you finally save your models like you did previously via torch.onnx.export and read their graph via onnx package (not torch.onnx) you will have...
for Net- input 5x3x10 and no transpose layer
graph torch-jit-export (
%input0[FLOAT, 5x3x10]
{
%76 = Shape(%input0)
%77 = Constant[value = <Scalar Tensor []>]()
for NetTensorFlowWrapper- input 5x10x3 and transpose layer
graph torch-jit-export (
%input0[FLOAT, 5x10x3]
{
%9 = Transpose[perm = [0, 2, 1]](%input0)
%77 = Shape(%9)
%78 = Constant[value = <Scalar Tensor []>]()
...

How to run inference using Tensorflow 2.2 pb file?

I followed the website: https://leimao.github.io/blog/Save-Load-Inference-From-TF2-Frozen-Graph/
However, I still do not know how to run inference with frozen_func(see my code below).
Please advise how to run inference using pb file in TensorFlow 2.2. Thanks.
import tensorflow as tf
def wrap_frozen_graph(graph_def, inputs, outputs, print_graph=False):
def _imports_graph_def():
tf.compat.v1.import_graph_def(graph_def, name="")
wrapped_import = tf.compat.v1.wrap_function(_imports_graph_def, [])
import_graph = wrapped_import.graph
print("-" * 50)
print("Frozen model layers: ")
layers = [op.name for op in import_graph.get_operations()]
if print_graph == True:
for layer in layers:
print(layer)
print("-" * 50)
return wrapped_import.prune(
tf.nest.map_structure(import_graph.as_graph_element, inputs),
tf.nest.map_structure(import_graph.as_graph_element, outputs))
# Load frozen graph using TensorFlow 1.x functions
with tf.io.gfile.GFile("/content/drive/My Drive/Model_file/froze_graph.pb", "rb") as f:
graph_def = tf.compat.v1.GraphDef()
loaded = graph_def.ParseFromString(f.read())
# Wrap frozen graph to ConcreteFunctions
frozen_func = wrap_frozen_graph(graph_def=graph_def,
inputs=["wav_data:0"],
outputs=["labels_softmax:0"],
print_graph=True)
You can use tf.graph_util.import_graph_def inside a tf.function to do that. For example, suppose you make a test GraphDef file my_func.pb like this:
import tensorflow as tf
# Test function to make into a GraphDef file
#tf.function
def my_func(x):
return tf.square(x, name='y')
# Get graph
g = my_func.get_concrete_function(tf.TensorSpec(None, tf.float32)).graph
# Write to file
tf.io.write_graph(g, '.', 'my_func.pb', as_text=False)
You can then load it and use it like this:
import tensorflow as tf
from tensorflow.core.framework.graph_pb2 import GraphDef
# Load GraphDef
with open('my_func.pb', 'rb') as f:
gd = GraphDef()
gd.ParseFromString(f.read())
#tf.function
def my_func2(x):
# Ensure the input is a tensor of the right type
x = tf.convert_to_tensor(x, tf.float32)
# Import the graph giving x as input and getting the output y
y = tf.graph_util.import_graph_def(
gd, input_map={'x:0': x}, return_elements=['y:0'])[0]
return y
tf.print(my_func2(2))
# 4

Serving a Tensorflow 2 Keras model with feature columns and preprocessing (migrating from tf 1.x estimators)

I'm migrating a current Tensorflow 1.x model built with estimators across to Tensorflow 2.0 Keras. The migration has been relatively smooth until it comes to serialising the model for serving.
The model is specified as follows
model = tf.keras.Sequential()
model.add(tf.keras.layers.DenseFeatures(feature_columns))
for units in hidden_layers:
model.add(tf.keras.layers.Dense(units, activation='relu'))
model.add(tf.keras.layers.Dense(2, activation=None))
I am using the Tensorflow feature columns api, which expects as input a dictionary of feature columns, and applying a transformation to those features before they pass into the model.
For example when training
def dataset_transformation_function(feature_dict: Dict[str, tf.Tensor]):
output_dict = feature_dict.copy()
output_dict['logx1'] = tf.math.log(feature_dict['x1'])
return output_dict
train_dataset = (
tf.data.Dataset.from_tensor_slices(
(train_feature_dict, train_label_vector)
)
.shuffle(n_train)
.batch(batch_size)
.map(dataset_transformation_function)
.repeat()
.prefetch(tf.data.experimental.AUTOTUNE)
)
It appears that to perform the same transformation at serve time I require:
input_tensors = [tf.Tensorspec(name=...), ...]
#tf.function(input_signature=input_tensors)
def dataset_transformation_function(args) -> Dict[str, tf.Tensor]:
...
And
tf.saved_model.save(
model,
MODEL_DIR,
signatures=feature_transform,
)
However I cannot determine the correct signature for the input tensor or the function.
The method I am migrating from is:
def serving_input_fn():
receiver_tensors = {
'x1': tf.placeholder(dtype=tf.float32, shape=[None, ], name='x1')
'x2': tf.placeholder(dtype=tf.string, shape=[None, ], name='x2')
}
features = dataset_transformation_function(
receiver_tensors
)
return tf.estimator.export.ServingInputReceiver(features, receiver_tensors)
estimator.export_savedmodel(
MODEL_DIR,
serving_input_fn,
as_text=False,
checkpoint_path=estimator.best_checkpoint,
)
To answer my own question, it seems that the solution is to provide a function which, when called does both the preprocessing and calls the model. Example here:
# tensorflow 2.0.0
import tensorflow as tf
import numpy as np
hidden_layers = [4,4]
feature_columns = [fc.numeric_column(name) for name in ['x1', 'x2', 'logx1']]
# construct a simple sequential model
model = tf.keras.Sequential()
model.add(tf.keras.layers.DenseFeatures(feature_columns))
for units in hidden_layers:
model.add(tf.keras.layers.Dense(units, activation='relu'))
model.add(tf.keras.layers.Dense(2, activation=None))
model.compile(
optimizer=tf.keras.optimizers.Adam(1e-3),
loss='mae',
metrics=['mae']
)
x_train = {'x1': np.arange(10), 'x2': np.arange(10), 'logx1': np.log1p(np.arange(10))}
x_predict = {'x1': np.arange(10), 'x2': np.arange(10)}
y = np.random.random(size=10)
model.fit(x=x_train, y=y)
trained_model_predictions = model.predict(x_train)
# preprocessing function for serving
#tf.function()
def serve_predict(x1, x2):
preprocessed_feature = tf.math.log1p(x1)
output = {
'x1': x1,
'x2': x2,
'logx1': preprocessed_feature
}
prediction = model(output)
return prediction
serve_predict = serve_predict.get_concrete_function(x1=tf.TensorSpec([None,]), x2=tf.TensorSpec([None,]))
tf.saved_model.save(
model,
'/tmp/tf',
signatures=serve_predict
)
# check the models give the same output
loaded = tf.saved_model.load('/tmp/tf')
loaded_model_predictions = loaded.serve_predict(x1=tf.range(10, dtype=tf.float32), x2=tf.range(10, dtype=tf.float32))
np.testing.assert_allclose(trained_model_predictions, loaded_model_predictions, atol=1e-6)

Could I use tf.session() in enviroment where keras only used?

Thanks for reading my question.
I was using keras to develop my reinforcement learning agent based on keres-rl. But I want to upgrade my agent so that I get some update from open ai base line code for better action exploration. But the code used tensorflow only. It is my first time to use tensorflow. I am so confused. I build keras deep learninng model using its "Model API". I have never concerned about inside of model. But the code I referenced was full of the code that kick in inside of deep learning model and give some change to its weight and get immediate layer output using tf.Session(). The framework is so flexible. Like below, using tf.Session() the tensor, which is recognized tensor and is not callable, can get result feeding feed_dict data. In keras, it is impossible as far as I know.
Once I allow using tf.Session(), my architecture will be complex and nobody wants to understand and use it except that I can adapt reference code more easily.
On the other side, if I don't allow that, I needs to break down my existing model and use tons of K.function to get middle layer's output or something that I can't get from keras model.
import numpy as np
from keras.layers import Dense, Input, BatchNormalization
from keras.models import Model
import tensorflow as tf
import keras.backend as K
import rl2.tf_util as U
def normalize(x, stats):
if stats is None:
return x
return (x - stats.mean) / (stats.std + 1e-8)
class RunningMeanStd(object):
# https://en.wikipedia.org/wiki/Algorithms_for_calculating_variance#Parallel_algorithm
def __init__(self, my, epsilon=1e-2, shape=()):
self._sum = K.variable(value=np.zeros(shape), dtype=tf.float32, name=my+"_runningsum")
self._sumsq = K.variable(value=np.zeros(shape) + epsilon, dtype=tf.float32, name=my+"_runningsumsq")
self._count = K.variable(value=np.zeros(()) + epsilon, dtype=tf.float32, name=my+"_count")
self.mean = self._sum / self._count
self.std = K.sqrt(K.maximum((self._sumsq / self._count) - K.square(self.mean), epsilon))
newsum = K.variable(value=np.zeros(shape), dtype=tf.float32, name=my+'_sum')
newsumsq = K.variable(value=np.zeros(shape), dtype=tf.float32, name=my+'_var')
newcount = K.variable(value=np.zeros(()), dtype=tf.float32, name=my+'_count')
self.incfiltparams = K.function([newsum, newsumsq, newcount], [],
updates=[K.update_add(self._sum, newsum),
K.update(self._sumsq, newsumsq),
K.update(self._count, newcount)])
def update(self, x):
x = x.astype('float64')
n = int(np.prod(self.shape))
totalvec = np.zeros(n*2+1, 'float64')
addvec = np.concatenate([x.sum(axis=0).ravel(), np.square(x).sum(axis=0).ravel(), np.array([len(x)],dtype='float64')])
self.incfiltparams(totalvec[0:n].reshape(self.shape),
totalvec[n:2*n].reshape(self.shape),
totalvec[2*n])
i = Input(shape=(1,))
# h = BatchNormalization()(i)
h = Dense(4, activation='relu', kernel_initializer='he_uniform')(i)
h = Dense(10, activation='relu', kernel_initializer='he_uniform')(h)
o = Dense(1, activation='linear', kernel_initializer='he_uniform')(h)
model = Model(i, o)
obs_rms = RunningMeanStd(my='obs', shape=(1,))
normalized_obs0 = K.clip(normalize(i, obs_rms), 0, 100)
tf2 = model(normalized_obs0)
# print(model.predict(np.asarray([2,2,2,2,2]).reshape(5,)))
# print(tf(np.asarray([2,2,2,2,2]).reshape(5,)))
with tf.Session() as sess:
sess.run(tf.global_variables_initializer())
print(sess.run([tf2], feed_dict={i : U.adjust_shape(i, [np.asarray([2,]).reshape(1,)])}))