Computer Colour Grading of Green Jadeite JadeBased on HSL Chroma Parameter

Hue, saturation and brightness is the basic parameters of jade colour grading. Based on the colour parameters extracted by colour digital camera, a computer analysis program is developed and the collected green jadeite jade images were classified. As a result, type, uniformity of colour can be received. Finally, the authors used the subjective classification and the GemDialogue card to verify this program's effectiveness, and proved that this method can realize a fast, objective and repeatable colour analysis of green jadeite jade.