Performing 1D Depthwise conv using Keras 2D Depthwise conv
Indeed I was able to prove that this method works, confirmed by my Matlab golden model. The problem was that in order to read the output activations of an intermediate layer in Keras, you have to create a separate model with the specified output.
This separate model in my case did not have the same weights as the original model, leading to incorrect outputs. But now that I read the output activations correct, I can confirm this method works.