As an important security technology, recently quantum watermarking attracted wide research attention. This study presents a blind quantum audio watermarking scheme based on quantum discrete cosine transform (qDCT). In the proposed scheme, the quantum audio signal in quantum representation of discrete signal (QRDS) is transformed into frequency domain using qDCT. The medium frequency components are selected as the target of watermarking. The qubits of previously scrambled watermark image are embedded in three qubits of each frequency component, and inverse qDCT is performed. The reverse process carried out to extract watermark qubits, in which majority voting policy employed to select correct watermark qubit. For every procedure of the proposed scheme, the quantum circuit and complexity analysis is presented. The novelty of the study is to embed watermark data in the medium frequency band of audio signal which is an optimal target for carrying hidden data. Furthermore, the proposed scheme employs parallel processing, the intrinsic powerful property of quantum computing, to perform embedding process efficiently and reduce quantum gates in presented quantum circuits. Based on transparency and robustness evaluation results, the proposed method demonstrated a better robustness than previous works, while keeping the same capacity, without significant change in transparency.

量子水印作为一种重要的安全技术，最近引起了广泛的研究关注。这项研究提出了一种基于量子离散余弦变换（qDCT）的盲量子音频水印方案。在提出的方案中，使用qDCT将离散信号的量子表示（QRDS）中的量子音频信号转换到频域。选择中频分量作为加水印的目标。将先前加扰的水印图像的量子比特嵌入每个频率分量的三个量子比特中，并且执行逆qDCT。进行相反的过程以提取水印量子位，其中多数表决策略用于选择正确的水印量子位。对于所提出方案的每个过程，都给出了量子电路和复杂度分析。该研究的新颖之处在于将水印数据嵌入音频信号的中频带，这是承载隐藏数据的最佳目标。此外，所提出的方案利用并行处理，量子计算的内在强大特性，来有效地执行嵌入过程并减少所提出的量子电路中的量子门。基于透明度和鲁棒性评估结果，所提出的方法显示出比以前的工作更好的鲁棒性，同时保持了相同的容量，而透明度没有明显变化。有效地执行嵌入过程并减少现有量子电路中的量子门。基于透明度和鲁棒性评估结果，所提出的方法显示出比以前的工作更好的鲁棒性，同时保持了相同的容量，而透明度没有明显变化。有效地执行嵌入过程并减少现有量子电路中的量子门。基于透明度和鲁棒性评估结果，所提出的方法显示出比以前的工作更好的鲁棒性，同时保持了相同的容量，而透明度没有明显变化。