Package steganography

Interface Steganography

All Known Implementing Classes:

AnimatedGif, ImageSteg, MP3Steganography, VideoSteg

public interface Steganography

Method Summary

Modifier and Type	Method	Description
byte[]	decode(byte[] steganographicData)	Decodes a hidden message in the given steganographicData and returns it as a byte array.
byte[]	decode(byte[] steganographicData, long seed)	Decodes a hidden message in the given steganographicData and returns it as a byte array.
byte[]	encode(byte[] carrier, byte[] payload)	Encodes the given payload in the given carrier (image, mp3, ...) and returns the result.
byte[]	encode(byte[] carrier, byte[] payload, long seed)	Encodes the given payload in the given carrier (image, mp3, ...) and returns the result.
boolean	isSteganographicData(byte[] data)	Tests whether the given data has a hidden message encoded in it.
boolean	isSteganographicData(byte[] data, long seed)	Tests whether the given data has a hidden message encoded in it.

Method Detail

encode

byte[] encode(byte[] carrier,
              byte[] payload)
       throws java.io.IOException,
              MediaNotFoundException,
              UnsupportedMediaTypeException,
              MediaReassemblingException,
              MediaCapacityException

Encodes the given payload in the given carrier (image, mp3, ...) and returns the result. The format of the returned media will be the same as carrier. Carrier needs to be an exact media representation as it would be read from a file by an InputStream.

Parameters:

carrier - media used to hide the payload

payload - data to hide

Returns:

steganographic data - exact media representation. Can be stored as it is to a file to open externally

Throws:

java.io.IOException - if a problem occurs during reading of carrier or payload

MediaNotFoundException - if the intended media (e.g. Image, Video, ...) could not be read from carrier

UnsupportedMediaTypeException - if the Media Type (e.g. JPG) is not supported

MediaReassemblingException - if a problem occurred during writing of the result media

MediaCapacityException - if the payload doesn't fit in the carrier

encode

byte[] encode(byte[] carrier,
              byte[] payload,
              long seed)
       throws java.io.IOException,
              MediaNotFoundException,
              UnsupportedMediaTypeException,
              MediaReassemblingException,
              MediaCapacityException

Encodes the given payload in the given carrier (image, mp3, ...) and returns the result. The format of the returned media will be the same as carrier. Carrier needs to be an exact media representation as it would be read from a file by an InputStream.

The Seed changes the way the payload is encoded. When decoding the result, the exact same Seed needs to be given to decode()

Parameters:

carrier - media used to hide the payload

payload - data to hide

seed - affects the resulting steganographic data (similar to a password)

Returns:

steganographic data - exact media representation. Can be stored as it is to a file to open externally

Throws:

java.io.IOException - if a problem occurs during reading of carrier or payload

MediaNotFoundException - if the intended media (e.g. Image, Video, ...) could not be read from carrier

UnsupportedMediaTypeException - if the Media Type (e.g. JPG) is not supported

MediaReassemblingException - if a problem occurred during writing of the result media

MediaCapacityException - if the payload doesn't fit in the carrier

decode

byte[] decode(byte[] steganographicData)
       throws java.io.IOException,
              MediaNotFoundException,
              UnsupportedMediaTypeException,
              UnknownStegFormatException

Decodes a hidden message in the given steganographicData and returns it as a byte array.

steganographicData needs to be an exact media representation as it would be read from a file by an InputStream.

This method only works if the message was encoded using no Seed or the respective default Seed. Otherwise it will throw an UnknownStegFormat as if no message was found.

Parameters:

steganographicData - Media containing the hidden message to decode

Returns:

the hidden message as a byte array

Throws:

java.io.IOException - if a problem occurs during reading of steganographicData

MediaNotFoundException - if the intended media (e.g. Image, Video, ...) could not be read from steganographicData

UnsupportedMediaTypeException - if the Media Type (e.g. JPG) is not supported

UnknownStegFormatException - if no hidden message was found

decode

byte[] decode(byte[] steganographicData,
              long seed)
       throws java.io.IOException,
              MediaNotFoundException,
              UnsupportedMediaTypeException,
              UnknownStegFormatException

Decodes a hidden message in the given steganographicData and returns it as a byte array.

steganographicData needs to be an exact media representation as it would be read from a file by an InputStream

This method only works if the message was encoded using the given Seed. Otherwise it will throw an UnknownStegFormatException as if no message was found.

Parameters:

steganographicData - Media containing the hidden message to decode

seed - seed that was used to encode the given stenographicData

Returns:

the hidden message as a byte array

Throws:

java.io.IOException - if a problem occurs during reading of steganographicData

MediaNotFoundException - if the intended media (e.g. Image, Video, ...) could not be read from steganographicData

UnsupportedMediaTypeException - if the Media Type (e.g. JPG) is not supported

UnknownStegFormatException - if no hidden message was found

isSteganographicData

boolean isSteganographicData(byte[] data)
                      throws java.io.IOException,
                             MediaNotFoundException,
                             UnsupportedMediaTypeException

Tests whether the given data has a hidden message encoded in it. This method only works if the message was encoded using the given Seed or the respective default Seed. Otherwise it will always return false.

The use of this method is discouraged. It saves very little resources compared to decode(...). So unless you need to test a lot of possible steganographicData, just use decode(...) and catch the UnknownStegFormatException

Parameters:

data - data to test

Returns:

true if the given data has a hidden message encoded in it

Throws:

java.io.IOException - if a problem occurs during reading of data

MediaNotFoundException - if the intended media (e.g. Image, Video, ...) could not be read from data

UnsupportedMediaTypeException - if the Media Type (e.g. JPG) is not supported

isSteganographicData

boolean isSteganographicData(byte[] data,
                             long seed)
                      throws java.io.IOException,
                             MediaNotFoundException,
                             UnsupportedMediaTypeException

Tests whether the given data has a hidden message encoded in it. This method only works if the message was encoded using the given Seed. Otherwise it will always return false.

The use of this method is discouraged. It saves very little resources compared to decode(...). So unless you need to test a lot of possible steganographicData, just use decode(...) and catch the UnknownStegFormatException

Parameters:

data - data to test

seed - seed the hidden message was encoded with

Returns:

true if the given data has a hidden message encoded in it

Throws:

java.io.IOException - if a problem occurs during reading of data

MediaNotFoundException - if the intended media (e.g. Image, Video, ...) could not be read from data

UnsupportedMediaTypeException - if the Media Type (e.g. JPG) is not supported