그림 2. 워터마크 비트를 삽입하기 위한 양자화 Fig. 2. Quantizer to embed watermark bit
그림 4. 워터마크 데이터 Fig. 4. Watermark data
그림 5. 워터마크가삽입된후에 HEVC 공격결과 (a) 원본, (b) QP=1, (c)QP=22, (d) QP=27, (e) QP=32, (f) QP=37 Fig. 5. HEVC attack result after watermark embedding (a) original,attacks with (b) QP=1, (c) QP=22, (d) QP=27, (e) QP=32, (f) QP=37
그림 6. 워터마크가삽입된이후에 (QP=22, HEVC 인코딩) HEVC 디코딩 결과 영상 (a) 0, (b) 2, (c) 4, (d) 6, (e) 8, (f) 10번째 프레임 Fig. 6. HEVC decoding result after watermark embedding (QP=22,HEVC Encoding) (a) 0th, (b) 2nd, (c) 4th, (d) 6th, (e) 8th, (f) 10thframe
그림 7. 추출된 워터마크의 비율 Fig. 7. Ratio of extracted watermark
그림 8. 하나의 GOP에서 추출된 최종 워터마크 Fig. 8. Extracted final watermark from one GOP group
그림 9. 각슬라이스에서추출된워터마크의예시 (a) I 슬라이스, (b) B 슬라이스, (c) P 슬라이스, (d) 통계적으로 종합한 최종 워터마크 Fig. 9. Example of watermarks extracted from each slice, (a) I slice,(b) B slice, (c) P slice, (d) Statistically summarized final watermark
그림 1. 워터마크 삽입 절차 Fig. 1. Watermark embedding procedure
그림 3. 워터마크 추출 절차 Fig. 3. Watermark extraction procedure
표 1. 각 부대역을 위한 파라미터 Table 1. Parameter values for each subband
표 2. 영상종류별 실험결과: 워터마크 삽입후의 화질(PSNR[dB])과 추출한 워터마크의 NCC값 Table 2. Experimental results for each kind of images: image quality after watermark embedding (PSNR[dB]) and NCC value of extracted watermark
표 3. HEVC 압축 공격에 대한 PSNR 결과 Table 3. PSNR results for HEVC compression attack
References
- W. M. Chen, C. J. Lai, H. C. Wang, H. C. Chao and C. H. Lo, "H.264 video watermarking with secret image sharing," 2009 IEEE International Symposium on Broadband Multimedia Systems and Broadcasting, Bilbao, Spain, pp.1-7, 2009, doi:10.1109/ISBMSB.2009.5133838.
- M. Fallahpour, S. Shirmohammadi, M. Semsarzadeh and J. Zhao, "Tampering Detection in Compressed Digital Video Using Watermarking," IEEE Transactions on Instrumentation and Measurement, Vol.63, No.5, pp.1057-1072, May 2014, doi:10.1109/TIM.2014.2299371.
- K. Ogawa and G. Ohtake, "Watermarking for HEVC/H.265 Stream," 2015 IEEE International Conference on Consumer Electronics (ICCE), Las Vegas, USA, pp.102-103, 2015, doi:10.1109/ICCE.2015.7066337.
- D-W. Kim, Y-G .Choi, H-S. Kim, J-S. Yoo, H-J. Choi and Y-H. Seo, "The problems in digital watermarking into intra-frames of H.264/AVC", Image and Vision Computing, Vol.28, No.8, pp.1220-1228, May. 2010, https://doi.org/10.1016/j.imavis.2009.12.006
- S. Gaj and P. K. Bora, "A robust watermarking scheme against re-compression attack for H.265/HEVC," IEEE 5th National Conference on Computer Vision, Pattern Recognition, Image Processing and Graphics (NCVPRIPG), Patna, India, pp.1-4, Dec. 2015, doi:10.1109/NCVPRIPG.2015.7490065.
- F. Alenizi, F. Kurdahi, A. Eltawil, and A. Aljumah, "DWT-based watermarking technique for video authentication," 2015 IEEE International Conference on Electronics, Circuits, and Systems (ICECS), Cariro, Egypt, pp.41-44, Dec. 2015, doi:10.1109/ICECS.2015.7440244
- Vidio set of JCT, ftp://hevc@ftp.tnt.uni-hannover.de/testsequences/(accessed Jan. 15, 2019).