Work (Reading, Mass.) · 2021
Issues in specifying contrast in building elements for people with a visual disability.
СтатьяНазвание и аннотация: Перевод в очереди
Обработка статьи · этапы, ошибки и управление
Загрузка состояния…
Ошибки и ограничения
История · было → стало
Состояние обновляется каждые 5 секунд, пока блок открыт. Процент показывается только там, где известен объём работы. Пауза останавливает продолжение этапа; текущий запрос к источнику может завершиться.
Dain Stephen John, Bridge Catherine, Relf Mark, Lukman Aldyfra Luhulima, Manandhar Sarita, Boon Mei Ying
Аннотация
BACKGROUND: Standards writers, national and international, have used different contrast calculations to set requirements in building elements for people with visual impairments. On the other hand, they have typically set a single requirement (30%) for specifying the minimum contrast. The systems are not linearly related and 30% means something rather different in each system.
OBJECTIVE: To provide a comparison of the various scales in order to illustrate the differences caused by multiple scales with a single compliance value, recommend a single scale for universal adoption and, if a new measure is problematic for implementation, to recommend the most perceptually uniform of the present methods.
METHODS: We use the contrast between combinations of 205 paint colours to illustrate the relationships between the measures. We use an internationally accepted scale, with equal perceptual steps, as a "gold standard" to identify the most perceptually uniform measurement scale in the existing methods.
RESULTS: We show that Michelson contrast is the most perceptually uniform of the existing measurement scales. We show the contrasts in the proposed method that equate to the various current requirements.
CONCLUSIONS: We propose that CIE Metric Lightness could be used as the contrast measure. Alternatively, Michelson contrast is the most perceptually linear of the current measurement scales.
OBJECTIVE: To provide a comparison of the various scales in order to illustrate the differences caused by multiple scales with a single compliance value, recommend a single scale for universal adoption and, if a new measure is problematic for implementation, to recommend the most perceptually uniform of the present methods.
METHODS: We use the contrast between combinations of 205 paint colours to illustrate the relationships between the measures. We use an internationally accepted scale, with equal perceptual steps, as a "gold standard" to identify the most perceptually uniform measurement scale in the existing methods.
RESULTS: We show that Michelson contrast is the most perceptually uniform of the existing measurement scales. We show the contrasts in the proposed method that equate to the various current requirements.
CONCLUSIONS: We propose that CIE Metric Lightness could be used as the contrast measure. Alternatively, Michelson contrast is the most perceptually linear of the current measurement scales.