First question: is the processed data relevant for any other component? Then may process the data on reducer level and put it in the redux state.
If it is only a process for this particular component then I would tend to put it in render. If the processing is costly then you can shift it to getDerivedStateFromProps because render get possibly called multiple times on any update circle.
And it’s quite ok for components having an own state while using redux. Just keep an eye on storing the data in the right and only one place.