You can not "extend" a patent. Unless you build something new. Still, the old stuff are in public domain after 20 years.
When the Sony/Philips patents for CD was dead, evolving it into a DVD or Blue Ray by them or others did not bring back the old patents for CD per see.
(There was other patents here, like the generic patents for optical disc, later acquired by Pioneer Corp in Japan, which for some reason had a extended filling time - (application was lost at the patent office) but for the sake of this discussion I try to keep it simple.)
The latest RED.com RAW patent can be read here, but heck there is just claims of the old stuff really, with the added methods of pre-/de-emphasis of the compressed data which to my understanding was not in the original "internally compressed RAW patent".
There seems to be just about a new form of "15-bit to 12-bit pre-emphasis function" now added to the redcode processing after RED switched from wavelet to DCI based compression. FIG 5 in the patent is all that is new.
https://ppubs.uspto.gov/dirsearch-public/print/downloadPdf/11503294
As far as I know there are other patents for the pre-/deemphasis of the wavelet based redcode which have now been abandoned for the later DCI compression. The internally compresed RAW patent is not about the compression, just the idea of 24+ FPS and >2K res RAW frames... Quite stupid. And neither the wavelet based (JPEG2000) or the DCI based compression is a invention by RED, it's just licensed for use in the redcode.