The implementation of the scaler node (which increases the size of the received image by a multiplier) is done and available in my github account: https://github.com/helen-fornazier/opw-staging
The debayer filter (from the previous Outreachy Status Log post) is also available there.
The scaler still doesn't work if the received image is in bayer format, I'll let this to a future patch.
The next patch will allow changes in the pad format by user space as the frame size and enumerate the supported pixel formats by the ioctls. I already have a sketch of this code but I need to test it a little more.