Java - Al leer y escribir un archivo la salida cambia

OutputStream outputStream = null;

FileReader fr = new FileReader("ruta\\entrada.PNG");

BufferedReader br = new BufferedReader(fr);

String linea;

while ((linea = br.readLine()) != null) {

	contenido += linea + "\n";

}

byte[] toBytes= contenido.getBytes();

InputStream inputStream = new ByteArrayInputStream(toBytes);

try {

	outputStream = new FileOutputStream(new File("ruta\\salida.PNG"));

        int read = 0;

	byte[] bytes = new byte[1024];

	while ((read = inputStream.read(bytes)) != -1) {

		outputStream.write(bytes, 0, read);

	}

	outputStream.close();

} catch (Exception e) {

e.printStackTrace();

}

inputStream.close();

File fil = ~~~~;

FileInputStream fis = null;

fis = new FileInputStream(fil);

byte[] bytess = IOUtils.toByteArray(fis);