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In Wyner-Ziv video coding system, motion estimation efficiency is much lower than that in conventional video coding system because current frame is not available when doing motion estimation. In this paper, we propose a successive resolution refinement algorithm to improve motion estimation efficiency. Based on our rate distortion analysis, we derive optimal down-sample ratio for two-stage successive...
A panoramic video is an image-based rendering (IBR) technique which provides users with a large field of view (e.g. 360 degree) on surrounding dynamic scenes. It includes not only the translational motions but also the non-translational motions, such as zooming, rotation and uneven stretching etc. This paper presents a motion compensated prediction scheme based on adaptive selection of motion models...
In this paper, we present a multi-scale Gabor phase-based stereo matching scheme. Unlike the mechanism in the existing phase-based stereo matching methods, where disparity is formulated as the ratio of phase difference between two views to the local frequency at the given position, we set up a robust data measure from multi-scale Gabor phases to greatly alleviate the negative effect of phase singularity...
The two key problems in video transcoding are complexity reduction and quality management. The complexity of H.264 encoding makes complexity reduction even more important. A good transcoder design reduces complexity with negligible loss in quality. While motion estimation complexity can be easily reduced by reducing the search range or eliminating the coding modes, these approaches will cause significant...
Motivated by the wide adoption of H.264 and the demand of universal multimedia data access over the expanding network with diverse devices, this paper studies H.264-based video transcoding with spatial resolution conversion. First, a practical solution for efficiently determining a reference frame is proposed to take advantage of the new feature of multiple references in H.264. Then, a motion vector...
In this paper, a video inpainting approach is proposed, which targets at repairing a video containing moving humans that are largely or completely occluded or missing for some of the frames. The proposed approach first categorizes typically periodic human motion in a video into a set of temporal states (called motion states), and then estimates the motion states for the frames with missing humans...
Variable block size motion estimation (VBSME) is the most computation consuming part in the newest H.264 /AVC video coding standard. To reduce computation, an ultra low-complexity fast VBSME algorithm is proposed in this paper. Different to previous fast algorithms which separately pressed the 7 block modes, in the presented algorithm, all the block modes are simultaneously calculated for most of...
In practical Wyner-Ziv video coding, every frame is encoded independently of others, but decoded based on the side information generated from adjacent frames. In Wyner-Ziv residual coding of video, the residual of a frame with respect to a reference frame is Wyner-Ziv encoded, which leads to a higher coding efficiency than directly Wyner-Ziv encoding the original frame. In previous work, the reference...
The recursive optimal per-pixel estimate (ROPE) is an effective end-to-end distortion estimation scheme. Most existing ROPE-based applications assume that: (i) the encoder knows exactly the actual packet loss rate and (ii) the decoder error concealment scheme; (iii) no deblocking in-loop filtering is employed. However, in practice, these assumptions may not all be valid. In this paper, we investigate...
An efficient stereo video coding method was proposed instead of calculating both disparity estimation (DE) and motion estimation (ME) of every stereo pairs. The first right frame was encoded firstly, and the first left frame was predicted by DE with adaptive windows. This first stereo pair was considered as "I stereo pair". According to occlusion correlation between disparity vectors (DVs)...
Block motion estimation with full search is computationally complex. To reduce this complexity, different methods have been proposed, including partial distortion, which can reduce the computational complexity with no loss of image quality. We propose a distortion-based partial distortion search (DPDS) based on the magnitude of distortion and adaptive update of the matching order. We calculate absolute...
In this paper, multi-pass and frame parallel algorithms are proposed to accelerate various motion estimation (ME) tools in H.264 with the graphics processing unit (GPU). By the multi-pass method to unroll and rearrange the multiple nested loops, the integer-pel ME can be implemented with two-pass process on GPU. Moreover, fractional ME needs six passes for frame interpolation with six-tap filter and...
Motion estimation has been widely studied and used to improve coding efficiency with small data access for power-saving. Conventional search area reuse algorithm requires small memory access by reuse of search area, but, suffers from coding efficiency degradation in fast motion video sequence. In this paper, we propose a search area selective reuse algorithm. The proposed algorithm well selects search...
Multiple reference frames and variable block sizes improve compression efficiency of H.264, however, they also increase the encoder complexity and motion estimation time. This paper proposes a new algorithm, called local reference with early termination (LRET) to reduce the H.264 motion estimation time without adding to the encoder complexity. The LERT algorithm rearranges the search order of the...
Seven variable block sizes are adopted for inter-frame MB (macroblock) coding in H.264. This new feature achieves significant coding gain. However, the computation complexity of the mode decision is extremely high when RD (rate distortion) algorithm is used. In this paper, we propose a fast mode decision algorithm with fast coding block size selection based on MB motion characteristic for inter frames...
Background modeling is an important approach for motion detection. The background model should adapt to dynamic change of the environment in time and generate background image with no moving foreground. Accordingly, we propose to incorporate the adaptive weight selection mechanism for roughly detected motion regions into the incremental eigen-background method. Comparing with existing works, we originally...
In this paper we present a new motion estimation scheme that minimizes the objective distance function with a constraint of similarity measure to exploit the motion correlation among adjacent pixel blocks with similar statistics features. We formulate this correlation as a similarity measure on the motion vectors between the current pixel block and its neighboring blocks weighted by the corresponding...
Image in-painting or image completion removes objects from a photo and automatically produces a visually pleasant result. However, to remove objects from a video, the resulting video may have ghost shadows even each individual frame is in-painted properly. We use motion estimation algorithm to separate objects and backgrounds into several layers. Objects in separated layers are in-painted from back...
A novel framework of multimodal human-machine or human-human interaction via real-time humanoid avatar communication is proposed for real-world mobile application. It integrates audio-visual analysis and synthesis modules to realize real-time head tracking, multichannel and runtime animations, visual TTS and real-time viseme detection and rendering. The 3D avatar provides customized modeling for low-bit...
This paper presents an enhanced trajectory-based ball detection and tracking algorithm, which acquires 2.5D ball position with the aid of camera motion recovery (CMR). Informally, CMR enhances the algorithm by obtaining better ball candidates and forming longer ball trajectories via computing 2.5D position of the ball. The algorithm in this paper comprises two phases. In the first phase, we achieve...
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