Room correction is a form of processing. I guess you mean you don't want video to be processed but you do want to process audio.
If my guess is right, the solution is simple. Oppo has two hdmi outputs. You can just connect hdmi1 directly to the TV and connect hdmi2 to a processor to do all the decoding and room correction. One of such processor I like is the Marantz AV7005.
If my guess is right, the solution is simple. Oppo has two hdmi outputs. You can just connect hdmi1 directly to the TV and connect hdmi2 to a processor to do all the decoding and room correction. One of such processor I like is the Marantz AV7005.