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3-D video will become one of the most significant video technologies in the next-generation television. Due to the ultra high data bandwidth requirement for 3-D video, effective compression technology becomes an essential part in the infrastructure. Thus multiview video coding (MVC) plays a critical role. However, MVC systems require much more memory bandwidth and computational complexity relative to mono-view video coding systems. Therefore, an efficient prediction scheme is necessary for encoding. In this paper, a new fast prediction algorithm, content-aware prediction algorithm (CAPA) with inter-view mode decision, is proposed. By utilizing disparity estimation (DE) to find corresponding blocks between different views, the coding information, such as rate-distortion cost, coding modes, and motion vectors, can be effectively shared and reused from the coded view channel. Therefore, the computation for motion estimation (ME) in most view channels can be greatly reduced. Experimental results show that compared with the full search block matching algorithm (FSBMA) applied to both ME and DE, the proposed algorithm saves 98.4-99.1% computational complexity of ME in most view channels with negligible quality loss of only 0.03-0.06 dB in PSNR.

Fractional motion estimation (FME) is widely used in video compression standards. In H.264/AVC, the precision of motion vector is down to quarter pixels to improve the coding efficiency. However, FME occupies over 45% of the computation complexity in an H.264 encoder and this high complexity limits the processing capability. In this paper, a single-iteration full search FME is proposed. By the algorithm and architecture co-optimization, the bandwidth to the frame buffer is reduced by 31%. Furthermore, 82% of circuit area for the Hadamard transformation and subtraction are saved from the direct implementation. Compared with prior arts, the proposed design supports 3.39 × higher throughput with only 0.02 dB PSNR drop. Thus, the specification of 4096 × 2160 quad full high definition H.264/AVC FME processing can be achieved.

To provide more vivid perception, more and more advanced features, like the 4k×2k resolution and the multiview functionality, are emerging for TV. For a multiview video coding (MVC) encoder, motion and disparity estimation (ME/DE) take at least half the hardware requirement. To solve these challenges, a cache-based integer ME/DE algorithm is proposed. With a cache memory as the search window buffer, a predictor-centered ME/DE algorithm is presented. The search range can be reduced to ±16 pixels with less than 0.1dB quality drop compared with full search algorithm. Based on this algorithm, an integer ME/DE chip design is realized. It can reduce 82% on-chip SRAM and 39% system bandwidth. Moreover, the search candidate requirement is also reduced by 79%. As the result, an ME/DE chip design for 4k×2k quad-HD H.264 and HDTV MVC is implemented.

External memory bandwidth is an important issue in system-on-chip (SoC) systems. Especially in high definition (HD) video coding, the bandwidth requirement of off-chip memory is critical in video processing. In recent researches, embedded compression shows high potential on off-chip memory bandwidth reduction. Works about embedded compression have been done for low power applications. However, there is no suitable efficient embedded compression with good rate-distortion performance for high throughput applications. In this paper, an algorithm and hardware architecture of high performance lossy embedded compression is proposed to ease the bus congestion problem while keeping the latency low. Using the proposed algorithm, not only the high throughput requirement of HD video encoder is met, but also the hardware cost is relatively low. From our simulation, about 70% memory bandwidth is reduced with only 0.1 dB PSNR degradation in 1080p HD video.

3-D video will become one of the most important video technologies in the next generation of television. Due to ultra high data bandwidth requirement for 3-D video, effective compression technology becomes an essential part in the infrastructure. Thus stereo and multiview video coding (MVC) plays a critical role. However, MVC systems require much more computational complexity relative to mono-view video coding systems. Therefore, an efficient prediction scheme is necessary for encoding. In this paper, a new fast motion estimation (ME) algorithm is proposed. By utilizing disparity estimation (DE) to find corresponding blocks between different views, the coding information such as motion vectors can be effectively shared and reused from the coded view channel. Therefore, the computation for ME in most view channels can be greatly reduced. Experimental results show that compared with the full search block matching algorithm applied to both ME and DE, the proposed algorithm saves 95% computation with near-FSBMA quality.

This paper presented a novel depth map generation method - the short-term motion assisted color segmentation, which combines the pictorial, monocular and binocular depth cues of human vision. The proposed method utilizes a motion/edge registration technique to avoid the motion jitter error in common motion segmentation. And the motion/image segment adaptation algorithm matches the connected components with the motion segments. Even for static scene, the connected component algorithm is still working for the depth map generation. The experimental results show that the adaptation of motion and image segmentation improves quality and smoothness of the depth map both in the spatial and temporal domain.

Multiview video coding (MVC) plays a critical role in 3D-TV systems. However, MVC require much more memory bandwidth and computational complexity relative to mono-view video coding. Therefore, an efficient prediction scheme is necessary for computation reduction. In this paper, a new fast prediction algorithm, computation-free motion estimation (ME) with inter-view mode decision, is proposed. By utilizing disparity estimation to find corresponding blocks between different views, the coding information, such as modes and motion vectors, can be effectively reused from the coded view channel. Therefore, the computation for ME can be almost totally neglected in most view channels. Besides, the proposed algorithm also provides the computation scalability. Experimental results show that compared with the full search block matching algorithm (FSBMA), the proposed algorithm not only save 61-72% computation with near-FSBMA quality, but save almost 100% computation with a little quality drop of 0.23-0.36 dB. Thus, computation-free ME is achieved.

Multiview video coding (MVC) systems require much more bandwidth and computational complexity relative to mono-view video systems. Thus, when designing a VLSI architecture for MVC systems, the hardware resource allocation is a critical issue. In this paper, we propose a new system bandwidth analysis scheme for various and complicated MVC structures. The precedence constraint in the graph theory is adopted for deriving the processing order of frames in a MVC system. In addition, current block centric scheduling (CBCS) and search window centric scheduling (SWCS) are proposed for MVC bandwidth analysis. By adopting data reuse schemes, several design points are explored with the aid of the proposed analysis scheme. The suitable hardware resource allocation can be easily determined.

The chip design of prediction core in the stereo video hybrid coding system is implemented with 0.18 mum 1P6M technology by TSMC. The die size is 4.53 mm. This IC can achieve real-time requirement under the operating frequency of 81 MHz for 30 D1 frames per second (fps) in the left and the right channel simultaneously, with ME/DE search range of [-64, +63] in horizontal direction and [-32, +31]/[-16, +15] in vertical direction. Compared with the hardware requirement for implementation of full search block matching algorithm (FSBMA), only 11.5% on-chip SRAM and 1/30 amount of PEs are needed. It shows that the hardware cost is quite small

Stereo video systems require double bandwidth and more than twice the computational complexity relative to mono-video systems. Thus, an efficient coding scheme is necessary for transmitting stereo video. We propose a novel stereo video coding system by exploiting a joint prediction scheme which combines three prediction schemes to achieve high coding efficiency and low computational complexity. Joint block compensation improves the visual quality. Motion vector prediction and mode pre-decision utilize the features of stereo video to reduce the computational complexity with up to 8-9 times acceleration. Experiments show that the proposed joint prediction scheme is 2 dB better than MPEG-4 TS and 3 dB better than MPEG-4 SP.