/** @see nextapp.echo2.app.StreamImageReference#render(java.io.OutputStream) */
public void render(OutputStream out) throws IOException {
if (isKeptInMemory()) {
byte[] bytes = (byte[]) refEncodedBytes.get();
//
// the GC may have reaped out bytes or the image may
// no longer be valid. Either way we need to encode.
//
if (bytes == null || !isValid()) {
Image image = getImage();
if (image == null) return;
ByteArrayOutputStream ba = new ByteArrayOutputStream();
encoder.encode(image, ba);
bytes = ba.toByteArray();
refEncodedBytes = new SoftReference(bytes);
setValid(true);
//
// tell any imagelisteners that the image has changed
update();
}
out.write(bytes);
} else {
Image image = getImage();
if (image == null) return;
encoder.encode(image, out);
}
}
public void testPngEncoderAvailable() throws UnsupportedEncoderException, IOException {
assertTrue(ImageEncoderRegistry.getInstance().isEncoderAvailable("image/png"));
final ImageEncoder imageEncoder = ImageEncoderRegistry.getInstance().createEncoder("image/png");
assertNotNull(imageEncoder);
final ByteArrayOutputStream bout = new ByteArrayOutputStream();
imageEncoder.encodeImage(
new BufferedImage(10, 10, BufferedImage.TYPE_INT_ARGB), bout, 0.75f, false);
assertTrue(bout.toByteArray().length > 0);
}
/**
* Encode the image in a specific format and write it to an OutputStream.
*
* @param image The image to be encoded.
* @param format The {@link ImageFormat} to use.
* @param outputStream The OutputStream to write the encoded image to.
* @param quality The quality to use for the image encoding (not supported by all ImageEncoders).
* @param encodeAlpha Whether to encode alpha transparency (not supported by all ImageEncoders).
* @throws IOException if there is an IO problem.
*/
public static void writeBufferedImage(
BufferedImage image,
String format,
OutputStream outputStream,
float quality,
boolean encodeAlpha)
throws IOException {
ImageEncoder imageEncoder = ImageEncoderFactory.newInstance(format, quality, encodeAlpha);
imageEncoder.encode(image, outputStream);
}
public static byte[] tryToDecodeSteganoImage(byte[] bytes, String key)
throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException,
InvalidAlgorithmParameterException, IllegalBlockSizeException, BadPaddingException {
try {
// 1. Try to load as image
BufferedImage img = ImageIO.read(new ByteArrayInputStream(bytes));
// 2. Try to read stegano data
short[] s = ImageEncoder.readBytesFromImage(img, key);
if (s == null) {
return null;
}
// Data inside image is too small, reject image
if (s.length < EncryptionProvider.SHA_256_HASH_SIZE_BYTES * 2) {
return null;
}
byte[] b = new byte[s.length];
for (int i = 0; i < b.length; i++) {
b[i] = (byte) (s[i] & 0xFF);
}
// 3. Try to decrypt bytes
byte[] decryptedBytes = null;
decryptedBytes = EncryptionProvider.decryptBytes(b, key.getBytes());
// 4. Try to decompress bytes
decryptedBytes = CompressionProvider.decompressBytes(decryptedBytes);
return decryptedBytes;
} catch (DataFormatException | IOException ex) {
ex.printStackTrace();
}
return null;
}
public static void encodeIntoImage(
File containerImg, File outputFile, byte[] srcBytes, String key) {
try {
BufferedImage in = ImageIO.read(containerImg);
BufferedImage newImage =
new BufferedImage(in.getWidth(), in.getHeight(), BufferedImage.TYPE_INT_ARGB);
Graphics2D g = newImage.createGraphics();
g.drawImage(in, 0, 0, null);
g.dispose();
srcBytes = CompressionProvider.compressBytes(srcBytes);
byte[] encryptedBytes = EncryptionProvider.encryptBytes(srcBytes, key.getBytes());
// Trick: convert from unsigned number to signed byte
short[] srcS = new short[encryptedBytes.length];
for (int i = 0; i < encryptedBytes.length; i++) {
srcS[i] = (short) (encryptedBytes[i] & 0xFF);
}
ImageEncoder.writeBytesToImage(in, encryptedBytes, outputFile.toString(), key);
System.out.println("[OK] Steganographic .png \"" + outputFile.toString() + "\" generated.");
} catch (DataFormatException ex) {
Logger.getLogger(ImageUtils.class.getName()).log(Level.SEVERE, null, ex);
} catch (NoSuchAlgorithmException
| NoSuchPaddingException
| InvalidKeyException
| InvalidAlgorithmParameterException
| IllegalBlockSizeException
| BadPaddingException
| ImageWriteException
| IOException ex) {
Logger.getLogger(ImageUtils.class.getName()).log(Level.SEVERE, null, ex);
}
}
/** @see java.io.Serializable */
private void writeObject(ObjectOutputStream out) throws IOException {
out.defaultWriteObject();
out.writeObject(encoder.getClass());
ImageKit.writeSerializedImage(out, getImage());
}
/** @see nextapp.echo2.app.StreamImageReference#getContentType() */
public String getContentType() {
return encoder.getContentType();
}
/**
* Encode the image in a specific format.
*
* @param image The image to be encoded.
* @param format The {@link ImageFormat} to use.
* @param quality The quality to use for the image encoding (not supported by all ImageEncoders).
* @return The byte[] that is the encoded image.
* @throws IOException if there is an IO problem.
*/
public static byte[] encode(BufferedImage image, String format, float quality)
throws IOException {
ImageEncoder imageEncoder = ImageEncoderFactory.newInstance(format, quality);
return imageEncoder.encode(image);
}
/**
* Encode the image in a specific format.
*
* @param image The image to be encoded.
* @param format The {@link ImageFormat} to use.
* @param encodeAlpha Whether to encode alpha transparency (not supported by all ImageEncoders).
* @return The byte[] that is the encoded image.
* @throws IOException if there is an IO problem.
*/
public static byte[] encode(BufferedImage image, String format, boolean encodeAlpha)
throws IOException {
ImageEncoder imageEncoder = ImageEncoderFactory.newInstance(format, encodeAlpha);
return imageEncoder.encode(image);
}
/**
* Encode the image in a specific format and write it to an OutputStream.
*
* @param image The image to be encoded.
* @param format The {@link ImageFormat} to use.
* @param outputStream The OutputStream to write the encoded image to.
* @throws IOException if there is an IO problem.
*/
public static void writeBufferedImage(
BufferedImage image, String format, OutputStream outputStream) throws IOException {
ImageEncoder imageEncoder = ImageEncoderFactory.newInstance(format);
imageEncoder.encode(image, outputStream);
}
