基于量化的水印嵌入算法可以实现盲检测,QIM(Quantized Index Modulation)是最常见的量化嵌入方法。量化步长是影响量化水印算法性能的最重要因素之一。本论文基于视觉模型的特点,针对多种具体的攻击,提出了对视觉模型进一步改进以及改进视觉模型下的四种不同水印嵌入算法,并将其与QIM相结合。实验结果表明本论文提出的算法对噪声干扰和常见的图像处理均具有较好的鲁棒性。论文最后给出总结和展望。
A scheme to design a simultaneous multichannel receiver is proposed to process multichannel signals in parallel, which is achieved by exploiting the attractive characteristics of a fast filter bank（ FFB）, such as cascaded structure, high frequency selectivity and lowcomputational complexity. Based on the minimization of the objective function, quantified in terms of the total number of multiplications required, subject to prescribed allowable ripples in the passband and stopband, the impulse response coefficients of the prototype filter in each stage are obtained to meet the requirements of the overall specifications for each channel at the receiver side. Simulations and experimental results on the frequency modulation（ FM） broadcast mutlichannel signal receiving system with the FM range from88 to 108 MHz, built upon the proposed FFB structure, are performed to verify its performance. Those results indicate that the proposed scheme is efficient in FM audio indexing applications and has a lower computational complexity, which is approximately 66. 4% of the weighted overlap and add（ WOLA） filter banks based solution.
