Convert image into raw features

Hi EI team,

Currently, I can run a NN model for image classification in my MCU. But the inputs of the model is raw features and I can only get it from edge impulse. In addititon, I want to display my input images, also.
So, I think that I must do both steps (running infernece and displaying image) locally without using EI.
Could you please help guide me how to convert from an image into raw features since I did not see any relating documnents, presently?