Is it possible to convert a color bitmap (or bitmapdrawable) into black and white? Unfortunately I don't think B4A supports ColorMatrix.
TIA
Widget
Here are some Java solutions I've found:
or
TIA
Widget
Here are some Java solutions I've found:
B4X:
protected Drawable convertToGrayscale(Drawable drawable)
{
ColorMatrix matrix = new ColorMatrix();
matrix.setSaturation(0);
ColorMatrixColorFilter filter = new ColorMatrixColorFilter(matrix);
drawable.setColorFilter(filter);
return drawable;
}
or
B4X:
Bitmap grayscaleBitmap = Bitmap.createBitmap(
colorBitmap.getWidth(), colorBitmap.getHeight(),
Bitmap.Config.RGB_565);
Canvas c = new Canvas(grayscaleBitmap);
Paint p = new Paint();
ColorMatrix cm = new ColorMatrix();
cm.setSaturation(0);
ColorMatrixColorFilter filter = new ColorMatrixColorFilter(cm);
p.setColorFilter(filter);
c.drawBitmap(colorBitmap, 0, 0, p);