如何在android中重新缩放位图文件？

Question

我目前有一个解码位图的方法来优化图像文件的大小，但是输入文件不会是位图，然后会解码为位图。所以我的问题是，如果我的输入已经是位图，我该如何调整它的大小？谢谢。

private Bitmap compressFile(File f) {
    int REQUIRED_SIZE = 80;
    try {
        // decode image size
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(new FileInputStream(f), null, o);

        // Find the correct scale value. It should be the power of 2.
        int width_tmp = o.outWidth;// , height_tmp = o.outHeight;
        int scale = 1;
        while (REQUIRED_SIZE > 0) {
            if (width_tmp <= REQUIRED_SIZE)
                break;
            width_tmp /= 2;
            // height_tmp /= 2;
            scale++;
        }

        // decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
    } catch (FileNotFoundException e) {
    }
    return null;
}

我想改成的是compressFile (Bitmap f)

Answer 1

你也可以用这个

Bitmap b = BitmapFactory.decodeByteArray(imageAsBytes, 0, imageAsBytes.length)
profileImage.setImageBitmap(Bitmap.createScaledBitmap(b, 120, 120, false));

或者你要求：

bitmap.compress(Bitmap.CompressFormat.PNG, quality, outStream);

查看this link了解更多信息