android压缩图片到指定尺寸

public static Bitmap zoomImage(Bitmap bgimage, double newWidth, double newHeight) {
// 获取这个图片的宽和高
float width = bgimage.getWidth();
float height = bgimage.getHeight();
// 创建操作图片用的matrix对象
Matrix matrix = new Matrix();
// 计算宽高缩放率
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
// 缩放图片动作
matrix.postScale(scaleWidth, scaleHeight);
Bitmap bitmap = Bitmap.createBitmap(bgimage, 0, 0, (int) width,
(int) height, matrix, true);
return bitmap;
}