scale image的方法

public static Bitmap scaleImg(Bitmap bm, int newWidth, int newHeight) {

// 获得图片的宽高

int width = bm.getWidth();

int height = bm.getHeight();

// 设置想要的大小

int newWidth1 = newWidth;

int newHeight1 = newHeight;

// 计算缩放比例

float scaleWidth = ((float) newWidth1) / width;

float scaleHeight = ((float) newHeight1) / height;



// 取得想要缩放的matrix参数

Matrix matrix = new Matrix();

matrix.postScale(scaleWidth, scaleHeight);

// 得到新的图片

Bitmap newbm = Bitmap.createBitmap(bm, 0, 0, width, height, matrix,

true);


if (width != newWidth && height != newHeight) {

freeBitmap(bm);

}

return newbm;



}