In this paper, information-theoretic analysis of

spread spectrum watermarking (SSW) is performed. The

analysis is focused on deriving channel capacity of SSW

system in order to determine the most embedding rate with ...

در این مقاله یکی از روش‌های مهم نهان‌نگاری بر روی VoIP، به نام روش پنهان‌سازی پژواک بهبود داده شده است. روش پنهان سازی پژواک علیرغم مزایای خوبی که در حفظ ویژگی‌های آماری و ادراکی سیگنال صوتی دارد و در مقابل حساسیت سامانه ...

bits) have been double expanded into multi

larger meaningful bits with applying BCH error correction code and Spread Spectrum technique in order to reduce errors in extraction phase. Approximation subband of two levels

DWT transform...

In this paper, we propose a DCT-based blind

watermarking scheme based on spread spectrum

communications. We compute the DCT of non overlapping

8x8 blocks of the host image. Then using the DC coefficients

of each block we...

and then apply DCT transform to each block. We use spread spectrum (SS) method for embedding the watermark bits. In our method a group of random bits are generated and embedded into high frequency coefficients of each block using SS method. For finding...

and then apply DCT transform to each block. We use spread spectrum (SS) method for embedding the watermark bits. In our method a group of random bits are generated and embedded into high frequency coefficients of each block using SS method. For finding...