Indeed there is, raven, but it doesn't work for me. The setting "All of the above" never changes anything. Does this work for you?

Even if it does work, some misguided vendors use their diffuse colour maps as the basis for bump, and this script disables the anti-gamma for that image wherever it is used.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)