This disclosure relates to the scalable system for controlling color management of the metadata grade including variation.Embodiment discloses the method for handling the image data for target indicator by a group metadata, and a group metadata is associated with picture material, and this method includes：Receive the decode image data；Determine whether to receive a group metadata associated with described image data；If receiving a group metadata associated with described image data, the parameter of color management algorithm is calculated according to a group metadata associated with described image data, wherein a group metadata includes at least：A. white point, is expressed as x, y chromaticity coordinate, and b. three primary colors are each expressed as x, y chromaticity coordinate, c. maximum brightness levels and d. minimum brightness levels.