after the quantization step in jpeg compression standard. It is based on decomposed application, if encryption and watermark are commutative, some computational .. fingerprint embedding and decryption for video distribution,” IEEE. 1 1 Commutative Encryption and Watermarking in Video Compression Ieee Transactions On Circuits And Systems For Video Technology, Vol. 17, No. 6, June. 1 1 Commutative Encryption and Watermarking in Video Compression 交換式 加密及浮水印法應用在視頻壓縮 IEEE Transactions on Circuits and Systems for.

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Each step consists of the following substeps: As in Craver and Katzenbeissers original protocol, the prover Alice generates a secret permutation and a graph.

In addition, we show that the presented CWE scheme can be integrated into a modified version of a protocol due to Craver and Katzenbeisser [ 2 ], enabling zero-knowledge verification of the watermark, meaning a verifier can verify the presence of a watermark without disclosure watermwrking the mark or the watermarking key.

Comkutative a first step, the embedder generates the amplitude histogram of the audio watermarjing and forms its relevant part as described in Section 3. Abstract We present a scheme for commutative watermarking-encryption CWE of audio data and demonstrate its robustness against an important class of attacks, Time-Scale Modifications TSM.

Commutative Watermarking-Encryption of Audio Data with Minimum Knowledge Verification

Introduction Commutative watermarking-encryption CWE means the combination of watermarking and encryption in such a way that the encryption and watermarking functions commute; that is, where is the encryption function, is the encryption key, is the watermarking key, is the cleartext media data, and is the mark to be embedded.

Note that if the histogram pairs in are revealed, but not their order, as in the protocol described in Section 6. Share buttons are a little bit lower. In [ 2 ], Katzenbeisser and Craver propose a probabilistic protocol which is in principle able to integrate any symmetric watermarking algorithm.

Advances in Multimedia

Image Communicationvol. These watermarks can be used to claim copyright, enforce copying restrictions, or track illegal copies offered on the Watermarkng.

If this list is used for extracting the watermark in permuted form, the result will be the permuted watermark. Auth with social network: For a bit watermark, the amount of data to be transferred between prover and verifier is about 4 Kilobytes per step.


At the same time, the obtained samples are quantized according to the bit depth available, the result being a set of sample valueswhere can be seen as a discrete time coordinate.

Indexed in Web of Science. Audio Watermarking Methods From the host of existing audio watermarking methods comprsesion [ 12 ] for an overviewthe method by Xiang et al. Bit error rates of extracted 56 bit watermarks after various StirMark attacks on seven example encrjption files. The presented CWE scheme is not fully commutative in theory because of the padding needed in the encryption step: Figure 2 shows the effect of the Cat Map after five iterations on the waveform of an example signal.

It is therefore an easy task for an attacker to modify those bins accordingly in order to remove the watermark. Waterjarking histogram part leading to the minimum dissimilarity is used to extract the remaining bits from.

The need for a CWE scheme becomes obvious in steps 3 and 4where an encrypted media object is watermarked and the presence of a watermark is verified in an encrypted object, watermzrking. Moreover, it is clear how to do this without knowledge of the watermarking key, as the permuted key will yield the permuted mark.

Craver and Katzenbeisser go on to show that if these steps are repeated times, Alice has probability to fool Bob into believing that her watermark is contained in. As embedding the mark has altered the mean value of the amplitude values, for extraction, the correct mean value has to be searched within a search space.

In general, it is hard compressoon devise a CWE algorithm which is robust against a wide class of attacks, because in a CWE scheme the embedder must be able to operate in the encrypted domain and therefore cannot rely upon important perceptual features compressiob the cover work. Registration Forgot your password?

The resulting PSNR between original and enciphered signal is Encrypted with the proposed method. If this is not the case, swap the bins by assigning new values to all samples in the bins. The proposed protocol has been implemented and extensively tested in Python.

The first bits of the watermark are used as synchronization sequence sync and should be known to the detector. In order to deploy a synchronization procedure for robustness against TSM attacks as described in [ 13 ], the original mean needs to be transferred separately to the verifier.

In this protocol, a prover Alice wants to prove the presence of a watermark to some verifier Bob without disclosing or the watermarking key. He can check the correctness of by verifying the hashvalue in.


Unauthorised embedding and detection of the watermark, on the other hand, encgyption difficult without knowledge of the watermarking key In what follows, we provide a lower bound of the number of possible keys.

If the permutation is generated by some alternative mechanism like, for example, the one proposed in encryptlon 21 ], which does not require padding, the scheme is fully commutative by construction. To cojpression best of our knowledge, no CWE schemes for audio data have been proposed so far. The watermarking bit is now embedded in the following way: On the other hand, a cloud service commytative or a client often has the need to search through commutahive client data according to certain metadata or tags.

CWE schemes can provide such a solution, if metadata are used as watermarks and embedded into the encrypted data. Technological, Economic, Legal and Political Aspectsvol. If encryption and watermarking do commute, their combination can serve as an important building block within a Digital Rights Management DRM System, as detailed further in Section 2.

Compressiom these parameter choices, the proposed watermarking algorithm is extremely robust against TSM attacks in resample mode, while the robustness against pitch-invariant mode is slightly worse, but still very good.

Researcher at Orange Education: In addition, watermarks are embedded into the media data to have an additional layer of protection which is present even after the data have been decrypted.

Performance analysis Perception Security. In addition, we show how the proposed CWE scheme can be integrated into a cryptographic protocol enabling public verification of the embedded mark without disclosing the mark or the watermarking key used for embedding. Moreover, the original histogram is largely unchanged by the padding cf.

Proposed watermarking and encryption scheme watermarkjng Most existing audio ciphering methods like, for example, [ 9 ] or [ 10 ], substitute the audio sample values and change i. To use this website, you must agree to our Privacy Policyincluding cookie policy.