Problem: How can i convert a .tflite (serialised flat buffer) to .pb (frozen model)? The documentation only talks about one way conversion.
Use-case is: I have a model that is trained on converted to .tflite but unfortunately, i do not have details of the model and i would like to inspect the graph, how can i do that?
I don't think there is a way to restore tflite back to pb as some information are lost after conversion. I found an indirect way to have a glimpse on what is inside tflite model is to read back each of the tensor.
interpreter = tf.contrib.lite.Interpreter(model_path=model_path)
interpreter.allocate_tensors()
# trial some arbitrary numbers to find out the num of tensors
num_layer = 89
for i in range(num_layer):
detail = interpreter._get_tensor_details(i)
print(i, detail['name'], detail['shape'])
and you would see something like below. As there are only limited of operations that are currently supported, it is not too difficult to reverse engineer the network architecture. I have put some tutorials too on my Github
0 MobilenetV1/Logits/AvgPool_1a/AvgPool [ 1 1 1 1024]
1 MobilenetV1/Logits/Conv2d_1c_1x1/BiasAdd [ 1 1 1 1001]
2 MobilenetV1/Logits/Conv2d_1c_1x1/Conv2D_bias [1001]
3 MobilenetV1/Logits/Conv2d_1c_1x1/weights_quant/FakeQuantWithMinMaxVars [1001 1 1 1024]
4 MobilenetV1/Logits/SpatialSqueeze [ 1 1001]
5 MobilenetV1/Logits/SpatialSqueeze_shape [2]
6 MobilenetV1/MobilenetV1/Conv2d_0/Conv2D_Fold_bias [32]
7 MobilenetV1/MobilenetV1/Conv2d_0/Relu6 [ 1 112 112 32]
8 MobilenetV1/MobilenetV1/Conv2d_0/weights_quant/FakeQuantWithMinMaxVars [32 3 3 3]
9 MobilenetV1/MobilenetV1/Conv2d_10_depthwise/Relu6 [ 1 14 14 512]
10 MobilenetV1/MobilenetV1/Conv2d_10_depthwise/depthwise_Fold_bias [512]
11 MobilenetV1/MobilenetV1/Conv2d_10_depthwise/weights_quant/FakeQuantWithMinMaxVars [ 1 3 3 512]
12 MobilenetV1/MobilenetV1/Conv2d_10_pointwise/Conv2D_Fold_bias [512]
13 MobilenetV1/MobilenetV1/Conv2d_10_pointwise/Relu6 [ 1 14 14 512]
14 MobilenetV1/MobilenetV1/Conv2d_10_pointwise/weights_quant/FakeQuantWithMinMaxVars [512 1 1 512]
15 MobilenetV1/MobilenetV1/Conv2d_11_depthwise/Relu6 [ 1 14 14 512]
16 MobilenetV1/MobilenetV1/Conv2d_11_depthwise/depthwise_Fold_bias [512]
17 MobilenetV1/MobilenetV1/Conv2d_11_depthwise/weights_quant/FakeQuantWithMinMaxVars [ 1 3 3 512]
18 MobilenetV1/MobilenetV1/Conv2d_11_pointwise/Conv2D_Fold_bias [512]
19 MobilenetV1/MobilenetV1/Conv2d_11_pointwise/Relu6 [ 1 14 14 512]
20 MobilenetV1/MobilenetV1/Conv2d_11_pointwise/weights_quant/FakeQuantWithMinMaxVars [512 1 1 512]
I found the answer here
We can use Interpreter to analysis the model and the same code looks like following:
import numpy as np
import tensorflow as tf
# Load TFLite model and allocate tensors.
interpreter = tf.lite.Interpreter(model_path="converted_model.tflite")
interpreter.allocate_tensors()
# Get input and output tensors.
input_details = interpreter.get_input_details()
output_details = interpreter.get_output_details()
# Test model on random input data.
input_shape = input_details[0]['shape']
input_data = np.array(np.random.random_sample(input_shape), dtype=np.float32)
interpreter.set_tensor(input_details[0]['index'], input_data)
interpreter.invoke()
output_data = interpreter.get_tensor(output_details[0]['index'])
print(output_data)
Netron is the best analysis/visualising tool i found, it can understand lot of formats including .tflite.
I have done this with TOCO, using tf 1.12
tensorflow_1.12/tensorflow/bazel-bin/tensorflow/contrib/lite/toco/toco --
output_file=coco_ssd_mobilenet_v1_1.0_quant_2018_06_29.pb --
output_format=TENSORFLOW_GRAPHDEF --input_format=TFLITE --
input_file=coco_ssd_mobilenet_v1_1.0_quant_2018_06_29.tflite --
inference_type=FLOAT --input_type=FLOAT --input_array="" --output_array="" --
input_shape=1,450,450,3 --dump_grapHviz=./
(you can remove the dump_graphviz option)
