Digital watermarking is a procedure to embedded watermark or logo into an image to avoid copyright and protect the image from being manipulated by others without owner approval. In the Technical and Vocational Education and Training (TVET) sector, the main challenge in watermarking is how to achieve high imperceptibility or visual quality and robustness without sacrificing the capacity of the cover image. In addition, the watermark should be ably extracted without any distortion. As for that, spiral scan embedding technique is used to overcome this issue. The performance of the proposed project is evaluated by comparing the results of extracting process using spiral scan technique with sequence technique, while the imperceptibility of the cover image is measured using Peak Signal Ratio (PSNR) and robustness of the watermarked image is measured using Normalized Cross Correlation (NCC). The result shows that the proposed technique obtains high imperceptibility and robustness.

1. M. Haribabu, C. H. Bindu, and K. V. Swamy, “A secure & invisible image watermarking scheme based on wavelet transform in HSI color space,” Procedia Computer Science, vol. 93, pp. 462–468, 2016. doi: https://doi.org/10.1016/j.procs.2016.07.234
2. C.-T. Hsu and J.-L. Wu, “Multiresolution watermarking for digital images,” IEEE Transactions on
   Circuits and Systems II: Analog and Digital Signal Processing, vol. 45, no. 8, pp. 1097–1101, 1998. doi: https://doi.org/10.1109/82.718818
3. J. J. O’Ruanaidh, W. Dowling, and F. Boland, “Watermarking digital images for copyright protection,” IEE Proceedings-Vision, Image and Signal Processing, vol. 143, no. 4, pp. 250–256, 1996. doi: https://doi.org/10.1049/ip-vis:19960711
4. J. Huang, Y. Q. Shi, and Y. Shi, “Embedding image watermarks in dc components,” IEEE transactions on circuits and systems for video technology, vol. 10, no. 6, pp. 974–979, 2000. doi: https://doi.org/10.1109/76.867936
5.  R. B. Wolfgang, C. I. Podilchuk, and E. J. Delp, “The effect of matching watermark and compression transforms in compressed color images,” vol. 1. In Proceedings of International Conference on Image Processing, ICIP 98, Chicago, IL: IEEE, 1998. doi: https://doi.org/10.1109/icip.1998.723519pp.440–444.
6.  R. B. Wolfgang and E. J. Delp, “Overview of image security techniques with applications in multimedia systems,” vol. 3228. In Proceedings of Multimedia Networks: Security, Displays, Terminals, and Gateways, Dallas, TX: International Society for Optics and Photonics, 1998. doi: https://doi.org/10.1117/12.300900pp.297–309.
7.  R. B. Wolfgang, C. I. Podilchuk, and E. J. Delp, “Perceptual watermarks for digital images and
   video,” Proceedings of the IEEE, vol. 87, no. 7, pp. 1108–1126, 1999. doi: https://doi.org/10.1109/5.771067
8.  P. W. Wong and N. Memon, “Secret and public key image watermarking schemes for image authentication and ownership verification,” IEEE Transactions on Image Processing, vol. 10, no. 10, pp.1593–1601, 2001. doi: https://doi.org/10.1109/83.951543
9.  F. Dragomir, O. E. Dragomir, M. E. Ivan, S. S. Iliescu, and I. Stanescu, “Optimal embedded system ˘for two-axis tracking PV panels,” Journal of Applied and Physical Sciences, vol. 3, no. 1, pp. 1–6,2017. doi: https://doi.org/10.20474/japs-3.1.1
10.  W. Zeng and B. Liu, “On resolving rightful ownerships of digital images by invisible watermarks,” vol. 1. Proceedings of International Conference on Image Processing, Santa Barbara, CA: IEEE, 1997, pp. 552–555.
11.  W. Zeng, and B. Liu, “A statistical watermark detection technique without using original images for resolving rightful ownerships of digital images,” IEEE Transactions on Image Processing, vol. 8, no. 11, pp. 1534–1548, 1999. doi: https://doi.org/10.1109/83.799882
12.  N. Nikolaidis and I. Pitas, “Robust image watermarking in the spatial domain,” Signal processing, vol. 66, no. 3, pp. 385–403, 1998. doi: https://doi.org/10.1016/s0165-1684(98)00017-6
13.  M. M. Yeung and F. Mintzer, “An invisible watermarking technique for image verification,” vol. 2. In Proceedings of International Conference on Image Processing, Santa Barbara, CA: IEEE, 1997, pp. 680–683.
14. S. P. Mohanty, P. Guturu, E. Kougianos, and N. Pati, “A novel invisible color image watermarking scheme using image adaptive watermark creation and robust insertion-extraction.” In Eighth IEEE International Symposium onMultimedia, ISM’06, San Diego, CA: IEEE, 2006. doi: https://doi.org/10.1109/ism.2006.7pp.153–160.
15. D. Vaishnavi and T. Subashini, “Robust and invisible image watermarking in RGB color space
    using SVD,” procedia computer science, vol. 46, pp. 1770–1777, 2015. doi: https://doi.org/10.1016/j.procs.2015.02.130
16.  M. A. Sayah, N. A. Kabir, and M. S. Jaafar, “Phantom study: Non uniformity quantity of technetium99m in different segments of myocardial spect image,” International Journal of Applied and Physical Sciences, vol. 3, no. 2, pp. 37–41, 2017. doi: https://doi.org/10.20469/ijaps.3.50002-2
17. D. Chopra, P. Gupta, G. Sanjay, and A. Gupta, “LSB based digital image watermarking for gray
    scale image,” IOSR journal of Computer Engineering, vol. 6, no. 1, pp. 36–41, 2012. doi: https://doi.org/10.9790/0661-0613641