在传真技术中，具有一系列处在图象黑电平与白电平之间色调的图象。

In facsimile, a picture having a range of toneslying between picture black and picture white.

youdao

在传真技术中，具有一系列处在图象黑电平与白电平之间色调的图象。

In facsimile, a picture having a range of toneslying between picture black and picture white.

youdao