Reduce a Bitmap on Android

reduceBitmap

// Disclaimer: this wasn't tested, it's just for teaching the way to a friend,
// maybe there are some bugs.

public void reduceBitmap(String sourcePath, String destinationPath) {
    // Adjust width and height to your needs
    int targetW = 800;
    int targetH = 600;

    // Get the dimensions of the bitmap
    BitmapFactory.Options bmOptions = new BitmapFactory.Options();
    bmOptions.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(sourcePath, bmOptions);
    int photoW = bmOptions.outWidth;
    int photoH = bmOptions.outHeight;

    // Determine how much to scale down the image
    int scaleFactor = Math.min(photoW/targetW, photoH/targetH);

    // Decode the image file into a Bitmap sized to fill the View
    bmOptions.inJustDecodeBounds = false;
    bmOptions.inSampleSize = scaleFactor;
    bmOptions.inPurgeable = true;

    Bitmap bitmap = BitmapFactory.decodeFile(sourcePath, bmOptions);

    final int BUFFER_SIZE = 1024 * 8;
    try {
        file.createNewFile();
        FileOutputStream fos = new FileOutputStream(destinationPath);
        final BufferedOutputStream bos = new BufferedOutputStream(fos, BUFFER_SIZE);
        bitmap.compress(CompressFormat.JPEG, 70, bos); // Adjust quality to your needs
        bos.flush();
    } catch (FileNotFoundException | IOException e) {
        e.printStackTrace();
    } finally {
        if (bos != null) {
            try {
                bos.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        if (fos != null) {
            try {
                fos.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}