import os
os.environ['CUDA_VISIBLE_DEVICES'] = ''
import numpy as np

from keras import regularizers
from keras import initializers
from keras import layers
from keras.models import Model

def get_model():
    inp = layers.Input(shape=(48,80,1))
    x = layers.Conv2D(32, 7)(inp)
    x = layers.BatchNormalization()(x)
    out = layers.ReLU()(x)
    return Model(inp, out)

if __name__ == '__main__':
    model = get_model()
    model.compile(optimizer='adam', loss='mse')

    X = np.random.rand(32, 48, 80, 1)
    y = np.random.rand(32, 42, 74, 32)

    model.fit(X, y, epochs=1, validation_data=(X, y))
    model.save('model.h5')

import onnxmltools
from keras.models import load_model

model = load_model('model.h5')
onnx_model = onnxmltools.convert_keras(model)

onnxmltools.utils.save_model(onnx_model, 'model.onnx')

import cv2
cv2.dnn.readNetFromONNX('model.onnx')

    ---------------------------------------------------------------------------
    error                                     Traceback (most recent call last)
    <ipython-input-3-6da663bc3421> in <module>
    ----> 1 cv2.dnn.readNetFromONNX("models/eyegaze_reduced.onnx")

    error: OpenCV(4.1.0) ../modules/dnn/src/layers/permute_layer.cpp:124: error: (-215:Assertion failed) inputs.size() > 0 in function 'getMemoryShapes'