Han Huang

Bio: Han Huang is an academic researcher from MediaTek. The author has contributed to research in topics: Coding tree unit & Motion compensation. The author has an hindex of 11, co-authored 34 publications receiving 435 citations. Previous affiliations of Han Huang include Beijing Jiaotong University.

Control-Point Representation and Differential Coding Affine-Motion Compensation

Abstract: The affine-motion model is able to capture rotation, zooming, and the deformation of moving objects, thereby providing a better motion-compensated prediction. However, it is not widely used due to difficulty in both estimation and efficient coding of its motion parameters. To alleviate this problem, a new control-point representation that favors differential coding is proposed for efficient compression of affine parameters. By exploiting the spatial correlation between adjacent coding blocks, motion vectors at control points can be predicted and thus efficiently coded, leading to overall improved performance. To evaluate the proposed method, four new affine prediction modes are designed and embedded into the high-efficiency video coding test model HM1.0. The encoder adaptively chooses whether to use the new affine mode in an operational rate-distortion optimization. Bitrate savings up to 33.82% in low-delay and 23.90% in random-access test conditions are obtained for low-complexity encoder settings. For high-efficiency settings, bitrate savings up to 14.26% and 4.89% for these two modes are observed.

Method and apparatus of video coding with affine motion compensation

Abstract: An encoding or decoding method with affine motion compensation includes receiving input data associated with a current block in a current picture, and deriving a first affine candidate for the current block including three affine motion vectors for predicting motion vectors at control points of the current block if the current block is coded or to be coded in affine Merge mode. The affine motion vectors are derived from three different neighboring coded blocks of the current block. An affine motion model is derived according to the affine motion vectors if the first affine candidate is selected. Moreover, the method includes encoding or decoding the current block by locating a reference block in a reference picture according to the affine motion model. The current block is restricted to be coded in uni-directional prediction if the current block is coded or to be coded in affine Inter mode.

Affine SKIP and DIRECT modes for efficient video coding

Abstract: Higher-order motion models were introduced in video coding a couple of decades ago, but have not been widely used due to both difficulty in parameters estimation and their requirement of more side information. Recently, researchers have put them back into consideration. In this paper, the affine motion model is employed in SKIP and DIRECT modes to produce a better prediction. In affine SKIP/DIRECT, candidate predictors of the motion parameters are derived from the motions of neighboring coded blocks, with the best predictor determined by rate-distortion tradeoff. Extensive experiments have shown the efficiency of these new affine modes. No additional motion estimation is needed, so the proposed method is also quite practical.

Method of Motion Vector Derivation for Video Coding

Abstract: A method and apparatus for deriving a sub-block motion vector for the current sub-block based on a motion-model function depending on the current sub-block location are disclosed. The derived sub-block motion vector is then used for encoding or decoding the sub-block. The motion-model function may correspond to an affine motion-model function or a bilinear motion-model function. In one embodiment, a new Merge mode can be used to apply prediction of a current block by applying prediction on the sub-block basis using the sub-block motion vector derived from the motion-model function. In another embodiment, an additional inter prediction mode can be used to apply prediction of a current block by applying prediction on the sub-block basis using the sub-block motion vector derived from the motion-model function.

Method and apparatus of video data processing with restricted block size in video coding

Abstract: A video data processing method comprises receiving input data associated with a current picture, determining a size for a current coding tree unit (CTU) or a current coding unit (CU) in the current CTU, and if the size, a width, or a height of the current CTU or CU is greater than a threshold, the encoder or decoder splits the current CTU or CU into multiple blocks until each block is not greater than the threshold. The current CTU or CU is processed for prediction or compensation and transform or inverse transform. The current CTU is processed according to CTU-level syntaxes signaled in a video bitstream. The encoder or decoder encodes or decodes the current CTU. The threshold corresponds to a maximum supported transform unit (TU) size for the encoder or decoder.

Control-Point Representation and Differential Coding Affine-Motion Compensation

Abstract: The affine-motion model is able to capture rotation, zooming, and the deformation of moving objects, thereby providing a better motion-compensated prediction. However, it is not widely used due to difficulty in both estimation and efficient coding of its motion parameters. To alleviate this problem, a new control-point representation that favors differential coding is proposed for efficient compression of affine parameters. By exploiting the spatial correlation between adjacent coding blocks, motion vectors at control points can be predicted and thus efficiently coded, leading to overall improved performance. To evaluate the proposed method, four new affine prediction modes are designed and embedded into the high-efficiency video coding test model HM1.0. The encoder adaptively chooses whether to use the new affine mode in an operational rate-distortion optimization. Bitrate savings up to 33.82% in low-delay and 23.90% in random-access test conditions are obtained for low-complexity encoder settings. For high-efficiency settings, bitrate savings up to 14.26% and 4.89% for these two modes are observed.

An Efficient Four-Parameter Affine Motion Model for Video Coding

Abstract: In this paper, we study a simplified affine motion model-based coding framework to overcome the limitation of a translational motion model and maintain low-computational complexity. The proposed framework mainly has three key contributions. First, we propose to reduce the number of affine motion parameters from 6 to 4. The proposed four-parameter affine motion model can not only handle most of the complex motions in natural videos, but also save the bits for two parameters. Second, to efficiently encode the affine motion parameters, we propose two motion prediction modes, i.e., an advanced affine motion vector prediction scheme combined with a gradient-based fast affine motion estimation algorithm and an affine model merge scheme, where the latter attempts to reuse the affine motion parameters (instead of the motion vectors) of neighboring blocks. Third, we propose two fast affine motion compensation algorithms. One is the one-step sub-pixel interpolation that reduces the computations of each interpolation. The other is the interpolation-precision-based adaptive block size motion compensation that performs motion compensation at the block level rather than the pixel level to reduce the number of interpolation. Our proposed techniques have been implemented based on the state-of-the-art high-efficiency video coding standard, and the experimental results show that the proposed techniques altogether achieve, on average, 11.1% and 19.3% bits saving for random access and low-delay configurations, respectively, on typical video sequences that have rich rotation or zooming motions. Meanwhile, the computational complexity increases of both the encoder and the decoder are within an acceptable range.

Fast Intra Prediction Based on Content Property Analysis for Low Complexity HEVC-Based Screen Content Coding

Abstract: Screen content coding (SCC) has evolved into the extension of the High Efficiency Video Coding (HEVC). Low-latency, real-time transport between devices in the form of screen content video is becoming popular in many applications. However, the complexity of encoder is still very high for intra prediction in HEVC-based SCC. This paper proposes a fast intra prediction method based on content property analysis for HEVC-based SCC. First, coding units (CUs) are classified into natural content CUs (NCCUs) and screen content CUs (SCCUs), based on the statistic characteristics of the content. For NCCUs, the newly adopted prediction modes, including intra block copy mode and palette mode are skipped, if the DC or PLANR mode is the best mode, after testing the traditional intra prediction rough modes. In addition, the quadtree partition process is also terminated due to the homogeneous and smooth block usually chooses a large size CU. For SCCUs, a rank-based decision strategy is introduced to terminate the splitting process of current CU. For all CUs, the bit per pixel of current CU is used to make a CU size decision. Meanwhile, the depth information of neighboring CUs and co-located CU are utilized to further improve the performance. Experimental results show that the proposed algorithm can save 44.92% encoding time on average with negligible loss of video quality.

Unified merge mode and adaptive motion vector prediction mode candidates selection

Abstract: A unified candidate block set for both adaptive motion vector prediction (AMVP) mode and merge mode for use in inter-prediction is proposed. In general, the same candidate block set is used regardless of which motion vector prediction mode (e.g., merge mode or AMVP mode) is used. In other examples of this disclosure, one candidate block in a set of candidate blocks is designated as an additional candidate block. The additional candidate block is used if one of the other candidate blocks is unavailable. Also, the disclosure proposes a checking pattern where the left candidate block is checked before the below left candidate block. Also, the above candidate block is checked before the right above candidate block.

Method and apparatus of video coding with affine motion compensation

Abstract: An encoding or decoding method with affine motion compensation includes receiving input data associated with a current block in a current picture, and deriving a first affine candidate for the current block including three affine motion vectors for predicting motion vectors at control points of the current block if the current block is coded or to be coded in affine Merge mode. The affine motion vectors are derived from three different neighboring coded blocks of the current block. An affine motion model is derived according to the affine motion vectors if the first affine candidate is selected. Moreover, the method includes encoding or decoding the current block by locating a reference block in a reference picture according to the affine motion model. The current block is restricted to be coded in uni-directional prediction if the current block is coded or to be coded in affine Inter mode.