A new adaptive vertex-based binary shape coding technique

IEICE Trans. Inf. & Syst.

Liu

Zhang

et al. 2013

SUMMARYIn this paper, we present a perceptual distortion measure (PDM) for polygon-based shape coding. We model the PDM as the salience of relevance triangle, and express the PDM by using three properties derived from the salience of visual part. Performance analysis and experimental results show that our proposal can improve the quality of the shape reconstruction when the object contour has sharp protrusions. key words: video coding, image coding, image quality

Section: Experiments Resultsmentioning

confidence: 99%

Perceptual Distortion Measure for Polygon-Based Shape Coding

IEICE Trans. Inf. & Syst.

Liu

Zhang

et al. 2013

“…One is the top-down [5] or bottom-up algorithm [6], which usually uses the object-adaptive vertex encoding method [7], and the other is the operational rate-distortion (ORD) optimal algorithm [2]. The ORD optimal algorithm aims at finding a polygon which can be encoded with the lowest bit rate associated with a given edge encoding scheme for an admissible distortion and vice versa [3].…”

Section: Introductionmentioning

confidence: 99%

Adaptive Edge Encoding Schemes for the Rate-Distortion Optimal Polygon-Based Shape Coding

Zhu

2014 Data Compression Conference

Liu

et al. 2014

In this paper, we present two adaptive edge encoding schemes for the operational ratedistortion optimal polygon-based shape coding. The encoding edge is represented by an octant number, a major component, and a minor component, where the ranges of the two components are determined at two levels. For the object-level, these ranges are either determined by users or adaptive to the contour characteristics and the predefined admissible distortions using the discrete contour evolution method. For the edge-level, the range of the minor component is further adaptive to the magnitude of the major component. The appropriate code tables are selected for the two components according to their ranges. Experiments on MPEG-4 test sequences showed that our schemes outperform existing schemes in terms of bit-rate at the same distortion level.

“…1 These two requirements have been extensively investigated in data compression [2][3][4] and pattern recognition fields [5][6][7] separately in two recent decades. The MPEG-4 video compression standard provides such functionalities by describing video objects not only by texture but also by shape.…”

Section: Introductionmentioning

confidence: 99%

“…[2][3][4] It treats the vertex selection and encoding separately; therefore, it loses the rate-distortion (RD) optimality. As a result, this representation can be directly applied to the contour-based object-oriented applications.…”

Section: Introductionmentioning

confidence: 99%

Operationally optimal vertex-based shape coding with arbitrary direction edge encoding structures

Zhu

Luo

2014

J. Electron. Imaging

The intention of shape coding in the MPEG-4 is to improve the coding efficiency as well as to facilitate the object-oriented applications, such as shape-based object recognition and retrieval. These require both efficient shape compression and effective shape description. Although these two issues have been intensively investigated in data compression and pattern recognition fields separately, it remains an open problem when both objectives need to be considered together. To achieve high coding gain, the operational rate-distortion optimal framework can be applied, but the direction restriction of the traditional eight-direction edge encoding structure reduces its compression efficiency and description effectiveness. We present two arbitrary direction edge encoding structures to relax this direction restriction. They consist of a sector number, a short component, and a long component, which represent both the direction and the magnitude information of an encoding edge. Experiments on both shape coding and hand gesture recognition validate that our structures can reduce a large number of encoding vertices and save up to 48.9% bits. Besides, the object contours are effectively described and suitable for the object-oriented applications.