在将照片上传到服务器之前减小 Android 中的照片大小

Question

我想在将照片上传到服务器之前减小 android 中的照片大小。如何在不影响图像优化的情况下做到这一点？

我还想允许用户裁剪图像，所以我找到了一些教程，但是通过 cmets，我知道用户在某些 android 版本中会出错。那么有什么方法可以让用户裁剪可以在所有安卓版本中使用的图像。

Answer 1

从您设备的图库中选择图片时，使用以下代码裁剪和缩小图片尺寸

Intent photoPickerIntent = new Intent(
                            Intent.ACTION_PICK,
                            android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
                    // photoPickerIntent.setType("image/*");
                    photoPickerIntent.putExtra("crop", "true");
                    photoPickerIntent.putExtra("outputX", 512);
                    photoPickerIntent.putExtra("outputY", 512);
                    photoPickerIntent.putExtra("aspectX", 1);
                    photoPickerIntent.putExtra("aspectY", 1);
                    photoPickerIntent.putExtra("scale", true);
                    File f = new File(android.os.Environment
                            .getExternalStorageDirectory(), "tt.jpg");

希望它有所帮助..快乐编码:)

Answer 2

public Bitmap decodeAndResizeFile(File f) {
        try {
            // Decode image size
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            BitmapFactory.decodeStream(new FileInputStream(f), null, o);

            // The new size we want to scale to
            final int REQUIRED_SIZE = 70;

            // 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 (true) {
                if (width_tmp / 2 < REQUIRED_SIZE
                        || height_tmp / 2 < REQUIRED_SIZE)
                    break;
                width_tmp /= 2;
                height_tmp /= 2;
                scale *= 2;
            }
            BitmapFactory.Options o2 = new BitmapFactory.Options();
            o2.inSampleSize = scale;
            return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
        } catch (FileNotFoundException e) {
        }
        return null;
    }


convert your bitmap object to file on=bject and use these ::->

File file = new File("your bitmap path ");
            Bitmap bmpp = decodeAndResizeFile(file);

Answer 3

试试这个它对我有用：

private Bitmap getBitmap(String path) {

Uri uri = getImageUri(path);
InputStream in = null;
try {
    final int IMAGE_MAX_SIZE = 1200000; // 1.2MP
    in = mContentResolver.openInputStream(uri);

    // Decode image size
    BitmapFactory.Options o = new BitmapFactory.Options();
    o.inJustDecodeBounds = true;
    BitmapFactory.decodeStream(in, null, o);
    in.close();



    int scale = 1;
    while ((o.outWidth * o.outHeight) * (1 / Math.pow(scale, 2)) > 
          IMAGE_MAX_SIZE) {
       scale++;
    }
    Log.d(TAG, "scale = " + scale + ", orig-width: " + o.outWidth + ", 
       orig-height: " + o.outHeight);

    Bitmap b = null;
    in = mContentResolver.openInputStream(uri);
    if (scale > 1) {
        scale--;
        // scale to max possible inSampleSize that still yields an image
        // larger than target
        o = new BitmapFactory.Options();
        o.inSampleSize = scale;
        b = BitmapFactory.decodeStream(in, null, o);

        // resize to desired dimensions
        int height = b.getHeight();
        int width = b.getWidth();
        Log.d(TAG, "1th scale operation dimenions - width: " + width + ",
           height: " + height);

        double y = Math.sqrt(IMAGE_MAX_SIZE
                / (((double) width) / height));
        double x = (y / height) * width;

        Bitmap scaledBitmap = Bitmap.createScaledBitmap(b, (int) x, 
           (int) y, true);
        b.recycle();
        b = scaledBitmap;

        System.gc();
    } else {
        b = BitmapFactory.decodeStream(in);
    }
    in.close();

    Log.d(TAG, "bitmap size - width: " +b.getWidth() + ", height: " + 
       b.getHeight());
    return b;
} catch (IOException e) {
    Log.e(TAG, e.getMessage(),e);
    return null;
}