A specification defining allowable luma and chroma code-values is applied in a region-of-interest encoding method of a mezzanine compression process. The method may include analyzing an input image to determine regions or areas within each image frame that contain code-values that are near allowable limits as specified by the specification. In addition, the region-of-interest method may comprise then compressing those regions with higher precision than the other regions of the image that do not have code-values that are close to the legal limits.