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Watermarking Part 2: Future Work. Robert J. Berger II. Michael P. Marcinak. Bijan G. Mobasseri. Electrical and Computer Engineering Department Villanova University 18 August 2004. Michael Marcinak. Watermarking Part 2: Future Work. Overview. JPEG Watermarking Software Current Version
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WatermarkingPart 2: Future Work Robert J. Berger II Michael P. Marcinak Bijan G. Mobasseri • Electrical and Computer Engineering Department • Villanova University • 18 August 2004 Michael Marcinak
Watermarking Part 2: Future Work Overview • JPEG Watermarking Software • Current Version • Enhancements • Additional Components • Video Applications • Error resiliency • MPEG 1|2|4, H.263, H.264 Michael Marcinak
Watermarking Part 2: Future Work JPEG Watermarking Software • Goals: • Produce a standalone package • Incorporate visual masking • Improve speed and efficiency • Maximize capacity Michael Marcinak
Watermarking Part 2: Future Work Current Version: Encoder Michael Marcinak
Watermarking Part 2: Future Work Final Version: Encoder Michael Marcinak
Watermarking Part 2: Future Work Visual Masking • Watermarking maps used VLC’s to unused VLC’s with different run/size • Run/size information of unused VLC’s must be modified in the Huffman table Michael Marcinak
Watermarking Part 2: Future Work Visual Masking • Three scenarios of visual masking: • watermarked VLC is longer than original • watermarked VLC is shorter than original • watermarked and original are the same length Michael Marcinak
Watermarking Part 2: Future Work Enhancements • Broaden scope from “lenaG.jpg” • Grayscale and color images • Potentially reduce file size • Remove zero padds (0xff00) by watermarking 1’s to 0’s Michael Marcinak
Watermarking Part 2: Future Work Additional Components • Maximize Capacity • Adapt binary tree to JPEG • Include run/size info • Intelligently select which bit to watermark • Improved Security Michael Marcinak
Watermarking Part 2: Future Work Video Applications • Goals: • Apply watermark algorithm to video Michael Marcinak
Watermarking Part 2: Future Work Video Applications • Real-time • Lossless • Preserved filesize • Format compliant Michael Marcinak
Watermarking Part 2: Future Work Video VLC Codespace • Unlike JPEG, VLC tables may not be complete Michael Marcinak
Watermarking Part 2: Future Work Watermarking Video • Problem: • By introducing a watermark into the bitstream, an unaware decoder may interpret bit errors • Solution: • Exploit error resiliency of various standards Michael Marcinak
Watermarking Part 2: Future Work Error Resiliency • Error propagation • Error concealment (decoder) • Error-resilient coding (encoder) • Error resilient techniques in current standards Michael Marcinak
Watermarking Part 2: Future Work Error Propagation • Bit errors usually result in loss of information between resynchronization markers Michael Marcinak
Watermarking Part 2: Future Work Error Concealment • Way of covering up corrupted data • Three types: • Spatial Interpolation - pixel blocks • Temporal Interpolation - motion vectors • Motion Compensated Temporal Prediction Michael Marcinak
Watermarking Part 2: Future Work Error-resilient Coding • Inserting Resynchronization Markers • Data Partitioning • Reversible Variable Length Codes (RVLC) Michael Marcinak
Watermarking Part 2: Future Work Inserting Resync Markers • Properties: • Uniquely distinguishable from other codewords • Intelligent placement - frames, slices, GOB • Usually long length • Enables decoder to regain synchronization • Reduces coding efficiency Michael Marcinak
Watermarking Part 2: Future Work Data Partitioning • Partition MB header, motion vectors, and DCT information separately • Limits error propagation • Separate watermarking MV and DCT information Michael Marcinak
Watermarking Part 2: Future Work Reversible Variable Length Codes • RVLC’s are uniquely decodable both forwards and backwards • Longer than regular VLC’s • Recovers more data • Reduces compression efficiency Michael Marcinak
Watermarking Part 2: Future Work Video Standards • MPEG 1/2 (MPEG 1991/1994) • H.263 (VCEG 1998) • MPEG 4 - Part 2 (MPEG 1999) • H.264 (Advanced Video Coding) (JVT 2001) Michael Marcinak
Resync Markers Data Partitioning RVLC MPEG 1/2 yes no yes H.263 yes yes yes MPEG 4 yes yes yes H.264 yes yes no Watermarking Part 2: Future Work Comparison Michael Marcinak
Watermarking Part 2: Future Work References • G. Cote, F. Kossentini, S. Wenger, “Error resilience Coding” in M. T. Sun, and A. Reibman, “Compressed Video over Networks” Marcel Dekker, 2000. • B. Girod, “Error-resilient Video”, Image, Video, and Multimedia Systems Group. • Li and Drew, “Fundamentals of Multimedia”, Prentice Hall, 2003. • D. P. K. Lun, “Error Resilient Coding Techniques”, Internet Technology for Multimedia Applications, 2002. • Y. Wang, S. Wenger, J. Wen, and A. Katsaggelos, “Review of Error Resilient Coding Techniques for Real-Time Video Communications”, Signal Processing Magazine. • S. Wenger et. al., “Error Resilience Support in H.263+”, IEEE Trans. CSVT 1998. • The International Telegraph and Telephone Consultative Committee, “Information Technology - Digital Compression and Coding of Continuous-Tone Still Images - Requirements and Guidelines”. CCITT Recommendation T.81, September 1992. • Telecommunication Standardization Sector of ITU, “Video coding for low bit rate communication”. ITU-T Recommendation H.263, February 1998. Michael Marcinak