MSScvm (MSS clear-view-mask) is an automated cloud and cloud shadow identification algorithm for MSS imagery. The algorithm is specific to the unique spectral characteristics of MSS data, relying on a simple rule-based approach. Clouds are identified based on green band brightness and the normalized difference between the green and red bands, while shadows are identified by near infrared band darkness and exclusion of topographic shadows and water though illumination correction and a separate water identification module. For more details please see the full MSScvm site: