https://blog.csdn.net/xdhywj/article/details/8886447

android 原生控件不支持gray16/8或者其他格式绘制。
可以转为灰度图。
图像灰度化：

public Bitmap bitmap2Gray(Bitmap bmSrc) {
// 得到图片的长和宽
int width = bmSrc.getWidth();
int height = bmSrc.getHeight();
// 创建目标灰度图像
Bitmap bmpGray = null;
bmpGray = Bitmap.createBitmap(width, height, Bitmap.Config.RGB_565);
// 创建画布
Canvas c = new Canvas(bmpGray);
Paint paint = new Paint();
ColorMatrix cm = new ColorMatrix();
cm.setSaturation(0);
ColorMatrixColorFilter f = new ColorMatrixColorFilter(cm);
paint.setColorFilter(f);
c.drawBitmap(bmSrc, 0, 0, paint);
return bmpGray;
}

2、对图像进行线性灰度变化

public Bitmap lineGrey(Bitmap image)
{
//得到图像的宽度和长度
int width = image.getWidth();
int height = image.getHeight();
//创建线性拉升灰度图像
Bitmap linegray = null;
linegray = image.copy(Config.ARGB_8888, true);
//依次循环对图像的像素进行处理
for (int i = 0; i < width; i++) {
for (int j = 0; j < height; j++) {
//得到每点的像素值
int col = image.getPixel(i, j);
int alpha = col & 0xFF000000;
int red = (col & 0x00FF0000) >> 16;
int green = (col & 0x0000FF00) >> 8;
int blue = (col & 0x000000FF);
// 增加了图像的亮度
red = (int) (1.1 * red + 30);
green = (int) (1.1 * green + 30);
blue = (int) (1.1 * blue + 30);
//对图像像素越界进行处理
if (red >= 255)
{
red = 255;
}

            if (green >= 255) {
                green = 255;
            }

            if (blue >= 255) {
                blue = 255;
            }
            // 新的ARGB
            int newColor = alpha | (red << 16) | (green << 8) | blue;
            //设置新图像的RGB值
            linegray.setPixel(i, j, newColor);
        }
    }
    return linegray;

}

3、对图像进行二值化

// 该函数实现对图像进行二值化处理
public Bitmap gray2Binary(Bitmap graymap) {
//得到图形的宽度和长度
int width = graymap.getWidth();
int height = graymap.getHeight();
//创建二值化图像
Bitmap binarymap = null;
binarymap = graymap.copy(Config.ARGB_8888, true);
//依次循环，对图像的像素进行处理
for (int i = 0; i < width; i++) {
for (int j = 0; j < height; j++) {
//得到当前像素的值
int col = binarymap.getPixel(i, j);
//得到alpha通道的值
int alpha = col & 0xFF000000;
//得到图像的像素RGB的值
int red = (col & 0x00FF0000) >> 16;
int green = (col & 0x0000FF00) >> 8;
int blue = (col & 0x000000FF);
// 用公式X = 0.3×R+0.59×G+0.11×B计算出X代替原来的RGB
int gray = (int) ((float) red * 0.3 + (float) green * 0.59 + (float) blue * 0.11);
//对图像进行二值化处理
if (gray <= 95) {
gray = 0;
} else {
gray = 255;
}
// 新的ARGB
int newColor = alpha | (gray << 16) | (gray << 8) | gray;
//设置新图像的当前像素值
binarymap.setPixel(i, j, newColor);
}
}
return binarymap;
}