AN ANALYSIS OF DIGITAL WATERMARKING IN FREQUENCY DOMAIN Presented by SRINIVAS KHARSADA PATNAIK ROLL # EI200118043 Under th...
DIGITAL WATERMARKING <ul><li>Form of data hiding or steganography. </li></ul><ul><li>Hides the message, so cannot be seen....
REQUIREMENTS <ul><li>Perceptual transparency </li></ul><ul><li>Robustness </li></ul><ul><li>Security </li></ul><ul><li>Pay...
FREQUENCY DOMAIN WATERMARKING <ul><li>First transformed to frequency domain. </li></ul><ul><li>Low frequency components ar...
BLOCK DIAGRAM REPRESENTATION [ ]
<ul><li>Two techniques for embedding </li></ul><ul><ul><li>Additive </li></ul></ul><ul><ul><li>multiplicative </li></ul></...
DISCRETE COSINE TRANSFORM <ul><li>Real domain transform </li></ul><ul><li>Represents image as coefficient of different fre...
DISCRETE FOURIER TRANSFORM <ul><li>Translation invariant </li></ul><ul><li>Modulated DFT amplitude coefficients </li></ul>...
DISCRETE WAVELET TRANSFORM <ul><li>Used when a signal is being sampled like digital signal or image processing. </li></ul>...
SHORT TIME FOURIER TRANSFORM <ul><li>The signal is divided into small stationary segments. </li></ul><ul><li>Used to acqui...
APPLICATIONS <ul><li>Copyright protection </li></ul><ul><li>Fingerprinting </li></ul><ul><li>Copy protection </li></ul><ul...
CONCLUSION  <ul><li>We can work for digital protection by the help of certain laws. </li></ul><ul><li>Time complexity of w...
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An analysis of digital watermarking in frequency domain

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An analysis of digital watermarking in frequency domain

  1. 1. AN ANALYSIS OF DIGITAL WATERMARKING IN FREQUENCY DOMAIN Presented by SRINIVAS KHARSADA PATNAIK ROLL # EI200118043 Under the Guidance of DR. SAROJ KUMAR MEHER Faculty in Electronics & Communication Engineering [ ]
  2. 2. DIGITAL WATERMARKING <ul><li>Form of data hiding or steganography. </li></ul><ul><li>Hides the message, so cannot be seen. </li></ul><ul><li>Maintains privacy and protects data from other viewers like hackers. </li></ul><ul><li>It may include hiding of numbers, logo or signature in the form of signal, image or video. </li></ul>[ ]
  3. 3. REQUIREMENTS <ul><li>Perceptual transparency </li></ul><ul><li>Robustness </li></ul><ul><li>Security </li></ul><ul><li>Payload of watermark </li></ul><ul><li>Oblivious and non-oblivious </li></ul>[ ]
  4. 4. FREQUENCY DOMAIN WATERMARKING <ul><li>First transformed to frequency domain. </li></ul><ul><li>Low frequency components are modified to contain text or signal. </li></ul><ul><ul><li>DCT </li></ul></ul><ul><ul><li>DFT </li></ul></ul><ul><ul><li>DWT </li></ul></ul><ul><ul><li>STFT </li></ul></ul>[ ]
  5. 5. BLOCK DIAGRAM REPRESENTATION [ ]
  6. 6. <ul><li>Two techniques for embedding </li></ul><ul><ul><li>Additive </li></ul></ul><ul><ul><li>multiplicative </li></ul></ul><ul><li>I=original image, W=watermark, I’=watermarked image, a=scaling factor. </li></ul>[ ]
  7. 7. DISCRETE COSINE TRANSFORM <ul><li>Real domain transform </li></ul><ul><li>Represents image as coefficient of different frequencies of cosines. </li></ul><ul><li>Forms the basis of the JPEG image compression algorithm. </li></ul><ul><li>Watermark </li></ul><ul><ul><li>detection </li></ul></ul><ul><ul><li>embedding </li></ul></ul><ul><ul><li>casting </li></ul></ul>[ ]
  8. 8. DISCRETE FOURIER TRANSFORM <ul><li>Translation invariant </li></ul><ul><li>Modulated DFT amplitude coefficients </li></ul><ul><li>Makes watermark image content dependent </li></ul>[ ]
  9. 9. DISCRETE WAVELET TRANSFORM <ul><li>Used when a signal is being sampled like digital signal or image processing. </li></ul><ul><li>Provides sufficient information for both analysis and synthesis of signal. </li></ul><ul><li>Reduction in computation time. </li></ul><ul><li>Separates image into sub images </li></ul>[ ]
  10. 10. SHORT TIME FOURIER TRANSFORM <ul><li>The signal is divided into small stationary segments. </li></ul><ul><li>Used to acquire frequency representation of the actual frames. </li></ul><ul><li>Precision determined by size of window. </li></ul><ul><li>Not a flexible approach. </li></ul>[ ]
  11. 11. APPLICATIONS <ul><li>Copyright protection </li></ul><ul><li>Fingerprinting </li></ul><ul><li>Copy protection </li></ul><ul><li>Broadcast monitoring </li></ul><ul><li>Indexing </li></ul><ul><li>Medical safety </li></ul>[ ]
  12. 12. CONCLUSION <ul><li>We can work for digital protection by the help of certain laws. </li></ul><ul><li>Time complexity of watermark signal can be enhanced by extending the length of watermark. </li></ul><ul><li>Can be used in any frequency domain that involves quantization and transformation. </li></ul>[ ]

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