Meaning of BOOLEAN in English
boolean images(also known as binary or logical images) contains only two parts with the values of 0 or 1. In a boolean image, 0 indicates a pixel that does not meet the desired condition.
Sean Woo's Finance, GIS and real estate English glossary. Английский глоссарий по ГИС(Географическая информационная система) и недвижимости Sean Woo's Finance. 2012