A real-time video watermarking system with buffer sharing for video-on-demand service

Real-time watermarking for streaming video (such as VOD service) requires significant amounts of computing resources. To address this issue, we present a scalable watermarking scheme integrated in a parallel MPEG-2 engine. A content-based block selection algorithm is proposed to efficiently embed the pseudo-random watermark signatures into DCT blocks. Our watermark scheme also provides a robust way to synchronize the watermarked video to the original source at detectors and is very resilient against cumulative and temporal attack.We optimize the parallel watermark engine to achieve real-time watermarking performance. We found that the system throughput could suffer significant degradation when processing high-level MPEG-2 video (such as HDTV) due to inefficient management of memory space. Therefore, we investigated an efficient buffer management scheme consisting of two methods: First we reduced the transmission buffer in slave nodes by frames sharing between frames in the Group-of-Picture (GOP) level. Then we further reduce the buffer space by a dynamic on-demand allocation on the slave side. By solving the memory-shortage bottleneck, the proposed system can support real-time watermarking for multiple high-resolution (up to 1404 × 960) video.