Extra image analysis, experiment and model from Perception of the global image contrast involves transparent spatial filtering and the integration and suppression of local contrasts (not root-mean-square contrast)

This material includes: (i) image analysis of pink noise, to further illustrate the motive behind the work; (ii) an experimental results figure and a brief description of the cognitive strategy involved in the task; (iii) a model involving a MAX() operator and global suppression that was omitted from the main report for clarity