Recently, neural network-based image compression techniques have demonstrated remarkable compression performance. The use of context-adaptive entropy models greatly enhances the rate-distortion (R-D) performance by effectively capturing spatial redundancy in latent representations. However, latent representations still contain some spatial correlations(e.g. same spatial structure), it needs to be eliminated by further processing. And many compression models are single-rate model, which is difficult to cover a big range of bitrate. In order to address this issue, we propose a novel variable-rate image compression algorithm that efficiently leverages bi-resolution spatial-channel information through learned mechanisms. In this paper, we first proposed a BRP network to divide our latent representations and side information into HR and LR components, eliminating the spatial redundancy in same location. Combining the spatial-channel context, we proposed a BSC context model, including a decreasing-granularity checkerboard pattern and channel grouping based on cosine slicing strategy. To cover a wide range of bitrate, we take a weight map as input to control bit allocation, achieving multiple compression rates. Our experimental results show that our method provides a better rate-distortion trade-off than BPG, JPEG and other recent image compression methods based on deep learning.

In recent years, there have been a growing interest in developing end-to-end neural video codecs. Previous works generally use a past decoded frame as reference directly, utilizing the motion information between it and the input frame to reduce temporal redundancy. However, this approach may lead to high bit rate consumption of the motion and fails to take advantage of the prior information in other reconstructed frames. In this work, We propose a learned video coding framework with optical flow based feature prediction module and decomposed context module. Specifically, we employ the previous optical flow to generate a warped frame, and along with other reconstructions, they are used for a more accurate reference forecasting, thereby reducing the bit rate required for motion compression. Moreover, based on the conditional coding framework, our decomposed context module explores conditional context in past decoded frames and further reduces additional spatiotemporal correlations. Experimental results demonstrate that our approach yields better performance than previous learned video compression methods and traditional standard codecs. For example, our neural codec achieves 28.94% coding gain over HEVC in PSNR metric and about 2.00% coding gain over VVC in MS-SSIM metric.

With the development of multimedia, video surveillance systems are becoming more popular. However, the current video surveillance systems have a general function and are unable to provide Intelligent perception.