java - 构建 IndexColorModel

Question

我想知道如何构建一个 IndexColourModel 。我不明白“位”参数参数。这是用于索引颜色图的内容，即从像素中使用的最低有效位的数量来索引图？该文档只是说明

bits - the number of bits each pixel occupies

我对此不满意，想知道是否有人可以阐明这个参数到底是什么以及它是如何使用的。这必须与其他“大小”参数相关吗？

Answer 1

位参数是 color depth .

来自IndexColourModel javadoc 位于类的顶部:

The values used to index into the colormap are taken from the least significant n bits of pixel representations where n is based on the pixel size specified in the constructor. For pixel sizes smaller than 8 bits, n is rounded up to a power of two (3 becomes 4 and 5,6,7 become 8). For pixel sizes between 8 and 16 bits, n is equal to the pixel size. Pixel sizes larger than 16 bits are not supported by this class. Higher order bits beyond n are ignored in pixel representations. Index values greater than or equal to the map size, but less than 2n, are undefined and return 0 for all color and alpha components.