Image Watermarking Algorithm Based on the Code Division Multiple Access Technique

Colour spaces effects on improved discrete wavelet transform‐based digital image watermarking using Arnold transform map

“…It should be mentioned, because of the different experimental methods and different parameters the comparison between different experimental results is difficult. However, from obtained results, it can be said that the proposed algorithm increases imperceptibility property in comparing with the similar algorithms in previous works such as [25–27]. So that, the PSNRs values of watermarked image, in [25] are about 48.2–49 dB for 24–72 watermark bit and in [26] and [27] are, respectively, about 33.234 dB and 35–36 dB, for 1024 watermark bit; While, the PSNRs of the watermarked images produced by the proposed scheme are all greater than 67 dB (in baboon in YIQ colour space) for 960 watermark bit.…”

“…In addition, embedding watermark in the intended channel of each colour space, increased security property, too. † Except HSI and HSV colour spaces, the proposed approach improves watermark imperceptibility in all colour spaces more than the obtained results in [25][26][27] and enhances robustness against JPEG compression and Gaussian noise attack, respectively more than the obtained results in [23,29] and [23]. † In correlation based watermarking techniques, JPEG-YCbCr colour spaces satisfy the imperceptibility property more than the other colour spaces.…”

“…The observations regarding the proposed watermarking scheme are summarised as follows: The watermarking security is more satisfactory than the earlier works such as [23]; so that, the watermark W is scrambled by ATM and after converting to a sequence, is adopted with a random binary sequence using a pseudo‐random number generator to encrypt the watermark. In addition, embedding watermark in the intended channel of each colour space, increased security property, too. Except HSI and HSV colour spaces, the proposed approach improves watermark imperceptibility in all colour spaces more than the obtained results in [25–27] and enhances robustness against JPEG compression and Gaussian noise attack, respectively more than the obtained results in [23, 29] and [23]. In correlation based watermarking techniques, JPEG‐YCbCr colour spaces satisfy the imperceptibility property more than the other colour spaces.…”

Non Correlation DWT Based Watermarking Behavior in Different Color Spaces

“…After a brief discussion on computational complexities, the similarity of original host images and watermarked images is measured by the standard correlation coefficient (Corr) as [26]: Moreover, the peak signal-to-noise ratio (PSNR) is used to evaluate the quality of the watermarked images as [27]: …”

“…In general, a watermarked image is acceptable by human perception if its PSNR is greater than 30 dBs. In other words, the correlation is used for evaluating the robustness of watermarking technique and the PSNR is used for evaluating the transparency of watermarking technique [26,28]. Fig.…”