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2019-11-25
Deka, Surajit, Sarma, Kandarpa Kumar.  2018.  Joint Source Channel Coding with Bandwidth Compression. 2018 5th International Conference on Signal Processing and Integrated Networks (SPIN). :286–290.
In this paper, we have considered the broadcasting of a memoryless bivariate Gaussian source over a Gaussian broadcast channel with respect to bandwidth compression. We have analysed the performance of a hybrid digital-analog (HDA) coding system in combination with joint source channel coding (JSCC) to measure the distortion regions. The transmission advantages due to the combination of both the analog and digital techniques, a class of HDA schemes that yields better performance in distortion is discussed. The performance of source and channel coding for the possible better outcome of the system is measured by employing Wyner-Ziv and Costa coding. In our model, we have considered the upper layer to be a combination of a hybrid layer in the sense of both the analog and digital processing is done. This is executed in presence of quantization error and performance of the system is measured with two conditions: 1) HDA scheme with quantization scaling factor α = 0, i.e. the input of the channel have only the analog information which is considered as the scaled quantization error βS 2) The analog information from the first layer S is suppressed by setting error scaling factor β = 0 and 3) Inclusion of recursive mode with JSCC in each of the three layers for the possible better outcome is considered here.
2019-01-31
Xu, Ke, Li, Yu, Huang, Bo, Liu, Xiangkai, Wang, Hong, Wu, Zhuoyan, Yan, Zhanpeng, Tu, Xueying, Wu, Tongqing, Zeng, Daibing.  2018.  A Low-Power 4096x2160@30Fps H.265/HEVC Video Encoder for Smart Video Surveillance. Proceedings of the International Symposium on Low Power Electronics and Design. :38:1–38:6.

This paper presents the design and VLSI implementation of a low-power HEVC main profile encoder, which is able to process up to 4096x2160@30fps 4:2:0 encoding in real-time with five-stage pipeline architecture. A pyramid ME (Motion Estimation) engine is employed to reduce search complexity. To compensate for the video sequences with fast moving objects, GME (Global Motion Estimation) are introduced to alleviate the effect of limited search range. We also implement an alternative 5x5 search along with 3x3 to boost video quality. For intra mode decision, original pixels, instead of reconstructed ones are used to reduce pipeline stall. The encoder supports DVFS (Dynamic Voltage and Frequency Scaling) and features three operating modes, which helps to reduce power consumption by 25%. Scalable quality that trades encoding quality for power by reducing size of search range and intra prediction candidates, achieves 11.4% power reduction with 3.5% quality degradation. Furthermore, a lossless frame buffer compression is proposed which reduced DDR bandwidth by 49.1% and power consumption by 13.6%. The entire video surveillance SoC is fabricated with TSMC 28nm technology with 1.96 mm2 area. It consumes 2.88M logic gates and 117KB SRAM. The measured power consumption is 103mW at 350MHz for 4K encoding with high-quality mode. The 0.39nJ/pixel of energy efficiency of this work, which achieves 42% $\backslash$textasciitilde 97% power reduction as compared with reference designs, make it ideal for real-time low-power smart video surveillance applications.