A Novel Rate Control Algorithm for H.264/AVC Considering Frame Activity

Rate control has significant impact on the video coding. However, the conventional rate control algorithm in the latest video coding standard H.264 without take into account the human visual system and result in video quality fluctuation. To address this problem, we propose a novel rate control algorithm for H.264/AVC considering frame activity. First, a method is proposed to detect the scene change in frames of video sequences. Second, bit allocation to frame is related to the frame activity which is calculated on the local motion activity and scene change in frames. And in the MB level, the number of bits allocated to each MB is determined by its local motion activity. Experimental results show that the proposed rate control algorithm can increase average PSNR by 0.9137 comparisons with the JVT-G012, and reduces the bit-rate error by up to 0.06%.

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Region-of-interest-based rate control scheme for high-efficiency video coding

APSIPA Transactions on Signal and Information Processing ◽

10.1017/atsip.2014.15 ◽

2014 ◽

Vol 3 ◽

Cited By ~ 9

Author(s):

Marwa Meddeb ◽

Marco Cagnazzo ◽

Béatrice Pesquet-Popescu

Keyword(s):

Video Coding ◽

Rate Control ◽

Control Algorithm ◽

High Efficiency ◽

Region Of Interest ◽

Bit Allocation ◽

Bit Rate ◽

High Efficiency Video Coding ◽

Control Scheme ◽

Rate Control Algorithm

This paper presents a novel rate control scheme designed for the newest high efficiency video coding (HEVC) standard, and aimed at enhancing the quality of regions of interest (ROI) for a videoconferencing system. It is designed to consider the different regions at both frame level and coding tree unit (CTU) level. The proposed approach allocates a higher bit rate to the region of interest while keeping the global bit rate close to the assigned target value. The ROIs, typically faces in this application, are automatically detected and each CTU is classified in a region of interest map. This binary map is given as input to the rate control algorithm and the bit allocation is made accordingly. The algorithm is tested, first, using the initial version of the controller introduced in HEVC test model (HM.10), then, extended in HM.13. In this work, we first investigate the impact of differentiated bit allocation between the two regions using a fixed bit rate ratio in intra-coded frames (I-frames) and Bidirectionally predicted frames (B-frames). Then, unit quantization parameters (QPs) are computed independently for CTUs of different regions. The proposed approach has been compared to the reference controller implemented in HM and to a ROI-based rate control algorithm initially proposed for H.264 that we adopted to HEVC and implemented in HM.9. Experimental results show that our scheme has comparable performances with the ROI-based controller proposed for H.264. It achieves accurate target bit rates and provides an improvement in region of interest quality, both in objective metrics (up to 2 dB in PSNR) and based on subjective quality evaluation.

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Adaptive Rate Control Algorithm for H.264/AVC Considering Scene Change

Mathematical Problems in Engineering ◽

10.1155/2013/373689 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 2

Author(s):

Xiao Chen ◽

Feifei Lu

Keyword(s):

Rate Control ◽

Control Algorithm ◽

Video Quality ◽

Video Communication ◽

Scene Change ◽

Adaptive Rate Control ◽

Adaptive Rate ◽

Rate Control Algorithm ◽

Additional Calculation

Scene change in H.264 video sequences has significant impact on the video communication quality. This paper presents a novel adaptive rate control algorithm with little additional calculation for H.264/AVC based on the scene change expression. According to the frame complexity quotiety, we define a scene change factor. It is used to allocate bits for each frame adaptively. Experimental results show that it can handle the scene change effectively. Our algorithm, in comparison to the JVT-G012 algorithm, reduces rate error and improves average peak signal-noise ratio with smaller deviation. It cannot only control bit rate accurately, but also get better video quality with the lower encoder buffer fullness to improve the quality of service.

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