The present disclosure pertains to an image-processing device and method that make it possible to suppress block noise. A βLUT_input calculator and a clip processor determine βLUT_input, which is a value inputted to an existing-β generator and an expanded-β generator. When the value of βLUT_input qp from the clip processor is 51 or less, the existing-β generator determines β using a LUT conforming to the HVEC standard, and supplies same to a filter process determination unit. When the value of βLUT_input qp from the clip processor is larger than 51, the expanded-β generator determines the expanded β and supplies same to the filter process determination part. This disclosure, for example, can be applied to an image processing device.

Image processing device and method

This disclosure describes techniques for coding transform coefficients associated with a block of residual video data in a video coding process. Aspects of this disclosure include the selection of a scan order for both significance map coding and level coding, as well as the selection of contexts for entropy coding consistent with the selected scan order. This disclosure proposes a harmonization of the scan order to code both the significance map of the transform coefficients as well as to code the levels of the transform coefficient. It is proposed that the scan order for the significance map should be in the inverse direction (i.e., from the higher frequencies to the lower frequencies). This disclosure also proposes that transform coefficients be scanned in subsets as opposed to fixed subblocks. In particular, transform coefficients are scanned in a subset consisting of a number of consecutive coefficients according to the scan order.

Coding of transform coefficients for video coding

A video coding or decoding method operable to generate blocks of quantised spatial frequency data by quantising the video data according to a selected quantisation step size and a matrix of data modifying the quantisation step size for use at different respective block positions within an ordered block of samples, the method being operable with respect to at least two different chrominance subsampling formats; comprises for at least one of the chrominance subsampling formats, defining one or more quantisation matrices as one or more predetermined modifications with respect to one or more reference quantisation matrices defined for a reference one of the chrominance subsampling formats.

Data encoding and decoding

Mobile video surveillance represents a new paradigm that encompasses, on the one side, ubiquitous video acquisition and, on the other side, ubiquitous video processing and viewing, addressing both computer-based and human-based surveillance. To this aim, systems must provide efficient video streaming with low latency and low frame skipping, even over limited bandwidth networks. This work presents MoSES (MObile Streaming for vidEo Surveillance), an effective system for mobile video surveillance for both PC and PDA clients; it relies over H.264/AVC video coding and GPRS/EDGE-GPRS network. Adaptive control algorithms are employed to achieve the best tradeoff between low latency and good video fluidity. MoSES provides a good-quality video streaming that is used as input to computer-based video surveillance applications for people segmentation and tracking. In this paper new and general-purpose methodologies for streaming performance evaluation are also proposed and used to compare MoSES with existing solutions in terms of different parameters (latency, image quality, video fluidity, and frame losses), as well as in terms of performance in people segmentation and tracking.

Video Streaming for Mobile Video Surveillance

Example techniques are described to determine transforms to be used during video encoding and video decoding. A video encoder and a video decoder may select transform subsets that each identify one or more candidate transforms. The video encoder and the video decoder may determine transforms from the selected transform subsets.

Enhanced multiple transforms for prediction residual

In one example, an apparatus for encoding video data includes a video encoder configured to select an intra-prediction mode to use to encode a block of video data, determine whether the block includes a sub-block of a size for which multiple transforms are possible based on the size of the sub-block and the selected intra-prediction mode, when the block includes the sub-block of the size for which multiple transforms are possible based on the size of the sub-block and the selected intra-prediction mode, select one of the multiple possible transforms, transform the sub-block using the selected one of the multiple possible transforms, and provide an indication of the selected one of the multiple possible transforms for the size of the block.

Signaling selected directional transform for video coding

An example method includes obtaining, for a current block of video data, values of motion vectors (MVs) of an affine motion model of a neighboring block of video data; deriving, from the values of the MVs of the affine motion model of the neighboring block, values of predictors for MVs of an affine motion model of the current block; decoding, from a video bitstream, a representation of differences between the values of the MVs of the affine motion model for the current block and the values of the predictors; determining the values of the MVs of the affine motion model for the current block from the values of the predictors and the decoded differences; determining, based on the determined values of the MVs of the affine motion model for the current block, a predictor block of video data; and reconstructing the current block based on the predictor block.

Affine motion prediction for video coding

Video streaming is one of the killer applications for cellular communications. The MPEG-4 fine-granularity scalability video coding technique can adapt to bandwidth variation and random packet errors. In this paper, to explore the impacts of cellular channel characteristics on the tolerance of buffer performance and quality of service, a novel statistical model-based adaptive media playout (AMP) is proposed by utilizing the statistical assumptions of both arrival and departure processes for a better decision on the dynamic threshold adjustment and frame-rate adjustment. Based on third-generation cellular transmission environment, simulation results will demonstrate that as compared to other AMP schemes, the proposed AMP control provides better visual quality with lower complexity.

https://ir.nctu.edu.tw:443/bitstream/11536/10249/1/000249842000016.pdf

Content-Aware Adaptive Media Playout Controls for Wireless Video Streaming

In one example, an apparatus for encoding video data includes a video encoder configured to scan a two-dimensional block of transform coefficients to produce a one- dimensional vector of the transform coefficients, determine values indicative of whether the transform coefficients in the one-dimensional vector are significant; and entropy encode at least one of the values using a context model selected based on at least a percentage of significant coefficients in a predetermined number of the values encoded before the at least one of the values.

Coding syntax elements for adaptive scans of transform coefficients for video coding

In this paper, History-based Motion Vector Prediction (HMVP) is presented for video coding. With the proposed method, a table of HMVP candidates is maintained and updated on-the-fly. After decoding one inter-coded block, the table is updated by appending the associated motion information to the table as a new HMVP candidate. A First-In-First-Out (FIFO) rule is applied to manage the table. The HMVP candidates could be added to the Advanced Motion Vector Prediction (AMVP) candidate list as additional motion vector predictors. And they could also be added to the merge candidate list as additional merge candidates. With the proposed method, the motion information of previously coded blocks even not adjacent to the current block can be utilized for more efficient motion vector prediction. Simulation results have validated the efficiency of HMVP, wherein up to 4% BD rate saving could be achieved. The proposed method has been adopted by the next generation video coding standard, named Versatile Video Coding (VVC) developed by Joint Video Exploration Team (JVET).

Hsiao-Chiang Chuang

Papers

Signaling selected directional transform for video coding

Affine motion prediction for video coding

Content-Aware Adaptive Media Playout Controls for Wireless Video Streaming

Coding syntax elements for adaptive scans of transform coefficients for video coding

History-Based Motion Vector Prediction in Versatile Video Coding