A scalable video coding (SVC) server can simultaneously provide a single bitstream with a fixed maximum service layer for different kinds of devices having different memory capacity, network bandwidth, and CPU perform...
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A scalable video coding (SVC) server can simultaneously provide a single bitstream with a fixed maximum service layer for different kinds of devices having different memory capacity, network bandwidth, and CPU performance requirements. An efficient hybrid 3D video service scheme is proposed without violation of the SVC standard technology for multiple transmission paths. A dynamic local disparity vector estimation algorithm is used to reflect the motion shift component between stereo views in the inter-layer prediction stage of the SVC encoder. To improve the coding efficiency, an adaptive search scheme based on distortion rates (DRs) between corresponding and reference macroblocks is used. Based on experimental results, up to 1.41 dB of quality improvement using JSVM 9.19 reference software is verified. (C) 2015 Elsevier B.V. All rights reserved.
scalable video coding (SVC) was recently standardized by the Joint video Team as an extension of H.264. In SVC, a computationally expensive exhaustive mode decision is employed to select the best coding mode for each ...
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scalable video coding (SVC) was recently standardized by the Joint video Team as an extension of H.264. In SVC, a computationally expensive exhaustive mode decision is employed to select the best coding mode for each macroblock (MB), which achieves a high coding efficiency. In order to reduce computational complexity, we propose an efficient SKIP mode detection approach for coarse grain quality SVC. It makes use of the coding information of spatial neighboring MBs and the co-located MB in base layer to predict the SKIP mode MB and early terminate its mode decision procedure. Experimental results show that the proposed early SKIP mode decision approach can achieve the average computational saving about 54% with almost no loss of rate distortion (RD) performance in the enhancement layer.
The rapid advances in the capture and display of high-dynamic range (HDR) image/video content make it imperative to develop efficient compression techniques to deal with the huge amounts of HDR data. Since HDR device ...
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The rapid advances in the capture and display of high-dynamic range (HDR) image/video content make it imperative to develop efficient compression techniques to deal with the huge amounts of HDR data. Since HDR device is not yet popular for the moment, the compatibility problems should be considered when rendering HDR content on conventional display devices. To this end, in this study, we propose three H. 264/AVC-based bit-depth scalablevideo-coding schemes, called the LH scheme (low bit-depth to high bit-depth), the HL scheme (high bit-depth to low bit-depth), and the combined LH-HL scheme, respectively. The schemes efficiently exploit the high correlation between the high and the low bit-depth layers on the macroblock (MB) level. Experimental results demonstrate that the HL scheme outperforms the other two schemes in some scenarios. Moreover, it achieves up to 7 dB improvement over the simulcast approach when the high and low bit-depth representations are 12 bits and 8 bits, respectively.
Requests from various video terminals push video servers to equip with scalability for video contents distribution in different ways. scalable video coding (SVC) as the extension of H.264/AVC standard can provide the ...
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Requests from various video terminals push video servers to equip with scalability for video contents distribution in different ways. scalable video coding (SVC) as the extension of H.264/AVC standard can provide the scalability for video servers by encodingvideos into one base layer and several enhancement layers. To enable mobile devices without scalability receive videos at their best extent, converting bit-streams from SVC into H.264/AVC becomes the key technique. Bit-stream rewriting is the simplest way without quality loss. However, rewriting is not a real transcoding scheme, since it needs to modify SVC encoders. This paper proposes a novel transcoding approach to support spatial scalability by minimizing the distortions generated from re-encoding process. The proposed scheme keeps the input bitstreams' information at maximum and adopts the hybrid upsampling method to do residue scaling, which can reduce the transcoding distortion into minimization. Experimental results demonstrate that the loss of the rate-distortion (RD) performance of the proposed transcoding scheme is better than Full Decoding Reencoding (FDR) which can get the highest video quality in general sense, by achieving up to 0.9 dB YPSNR gain while saving 95%~97% processing time.
Proposed is a fast encoding algorithm which avoids the repetition of the motion estimation process in the current scalable video coding (SVC) codec. Experimental results show that the proposed algorithm can reduce enc...
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Proposed is a fast encoding algorithm which avoids the repetition of the motion estimation process in the current scalable video coding (SVC) codec. Experimental results show that the proposed algorithm can reduce encoding time by 29.69-37.80%, while the coding performance of the SVC codec adopting the proposed algorithm is exactly the same as that of the original one.
In this paper, we propose a visually lossless accuracy model for scalablecoding of motion vectors in overcomplete wavelet-based scalablevideo codec. By exploiting theory of stationary random process, we first estima...
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In this paper, we propose a visually lossless accuracy model for scalablecoding of motion vectors in overcomplete wavelet-based scalablevideo codec. By exploiting theory of stationary random process, we first estimate motion compensation errors in spatial domain due to inaccurate motion vectors. We then extend the results to overcomplete wavelet domain, and further derive the errors caused by fraction-pixel motion vectors. Finally, combining with a visibility model of wavelet coefficient errors, we propose a novel algorithm to estimate the accuracy threshold of motion vectors with which motion compensation errors will be invisible. Experimental results show that our algorithm is effective in estimating visually lossless accuracy threshold of motion vectors. The proposed algorithm can also be used in scalable motion estimation in wavelet domain. It can accelerate motion estimation speed by stopping halfway at the accuracy that will not cause any visible errors.
The use of a novel motion compensated spatio-temporal nonseparable filter (MCSTF) is proposed for scalable video coding. This filter is an alternative to the present motion-compensated temporal filtering (MCTF), a fun...
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The use of a novel motion compensated spatio-temporal nonseparable filter (MCSTF) is proposed for scalable video coding. This filter is an alternative to the present motion-compensated temporal filtering (MCTF), a fundamental component for scalable video coding in the next generation. MCTF improve the coding efficiency and provide the temporal scalability. We classify MCSTF as a non-separable sub-sampling version of MCTF, and it provides interlaced pictures as intermediate video sequence by using a spatio-temporal split process. Furthermore, its 1/3-transform structure, which excludes the lifting-update-step, significantly suppresses the PSNR fluctuation that occurs when the existing MCTF technique is used. Our proposed system suppresses PSNR fluctuation with a higher average PSNR than the existing MCTF. Two types of sub-sampling lattices were investigated: the vertical-temporal (VT) quincunx and the face-centered orthorhombic (FCO) ones. Experimental results with entropy coded scalar quantization show the signifaicance of our proposed technique.
scalable video coding （SVC） is a newly emerging standard to be finalized as an extension of H.264/AVC. The most attractive characters in SVC are the inter layer prediction techniques, such as Intra_BL mode. But in c...
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scalable video coding （SVC） is a newly emerging standard to be finalized as an extension of H.264/AVC. The most attractive characters in SVC are the inter layer prediction techniques, such as Intra_BL mode. But in current SVC scheme, a uniform up-sampling filter （UUSF） is employed to magnify all components of an image, which will be very inefficient and result in a lot of redundant computational complexity. To overcome this, we propose an efficient component-adaptive up-sampling filter （CAUSF） for inter layer interpolation. In CAUSF, one character of human vision system is considered, and different up- sampling filters are assigned to different components. In particular, the six-tap FIR filter used in UUSF is kept and assigned for luminance component. But for chrominance components, a new four-tap FIR filter is used. Experimental results show that CAUSF maintains the performances of coded bit-rate and PSNR-Y without any noticeable loss, and provides significant reduction in computational complexity.
In video applications including video broadcasting, interactive TV and IPTV, video streams are transmitted over various networks. In order to fulfill the requirement of video devices to cut-in broadcasting, start play...
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In video applications including video broadcasting, interactive TV and IPTV, video streams are transmitted over various networks. In order to fulfill the requirement of video devices to cut-in broadcasting, start playback at a random location and jump to another location, the video service provider has to implement the random access functionality. Furthermore, the random access points can also enable the user devices to refresh the decoding process in error-resilient transmission. In this paper, we propose a novel transocding algorithm to insert random access points in the pre-encoded scalablevideo streams. Experiments show that the proposed algorithm can get 0.5~2.1dB PSNR gain over full decode and recode (FDR) transcoder and get 0.8~4dB PSNR gain over cascade pixel domain transcoder(CPDT). Simulation results also display that the proposed transcoding algorithm can reduce the computational complexity significant compared with FDR and CPDT method.
A significant problem in digital television broadcasting is the introduction of new coding techniques when new formats arrive. If the new codec is not fully compatible with the previous one, then backward compatibilit...
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