|
The display is a key element in the softcopy image chain. If the display is not optimized, information is lost. Studies seeking to assess the effects of bandwidth compression and image enhancement will reach false conclusions unless the display system is optimized. Although standards exist for the display of text and symbology, no such standards exist for continuous tone imagery. To help remedy this situation, a series of studies were conducted to help define guidelines for the effective display of continuous tone imagery, with emphasis on surveillance and reconnaissance imagery. Imagery of various types (visible, IR, multispectral, SAR) was displayed on cathode ray tube (CRT) and active matrix liquid crystal displays (AMLCD) that varied in luminance and spatial resolution performance. Over a series of eight studies, trained imagery analysts provided National Imagery Interpretability Ratings (NIIRS) and Briggs target ratings (a measure of minimum discriminable target size as a function of contrast) to assess the impact of display variations. From these studies, recommendations were derived for display pixel density, contrast modulation, and luminance measures including dynamic rang, ambient light level, color temperature, and perceptual linearization. This paper defines the display performance measures used, performance measurement procedures, and presents guidelines for display optimization. Results of studies supporting the guidelines are summarized. Use of the guidelines is recommended in any study involving softcopy display of continuous tone imagery.
|
