Hello @ray_pixar,
Something like this would need to hook the codec API, which SQLCipher is already using extensively. It would probably need to do something very special for compressed databases, along the lines of pre-processing to compress, encrypt and pack the data. This would result in a read only database, since it wouldn’t be feasible to allow rewrites of pages because depending on the content, the size of the data could change (e.g. consider a case where some content contained a series of strings all with the same character, which would be highly compressed, and then it was updated to contain random data, which would not be as compressible).
We can’t really provide any more specific guidance on how to do this. I suspect that it would not be a trivial implementation. That said, I should also mention that Zetetic does provide commercial customization services for SQLCipher, and this is something we could potentially explore. If you’re interested, feel free to get in touch with us at sales@zetetic.net.