You can add edge enhancement or smoothness to a Jpeg, or vary the colour depth.
你可以对格式的图像进行锐化或钝化，或改变颜色的深浅。
《柯林斯英汉双解大词典》
2
The fluid-rock interaction in some jadeite jade, as well as the enhancement of colour and structure could be observed in the secondary reducing process.
一些翡翠在表生还原条件下可观察到明显的水岩反应过程以及颜色与组织的改变。
3
Also discussed are characters and application of the nuclear radiation sources for the gem colour-enhancement process, and the mechanics and effect of the gem colour induced by radiation.