A Rotation-Invariant Approach to 2D Shape Representation Using the Hilbert Curve

  title={A Rotation-Invariant Approach to 2D Shape Representation Using the Hilbert Curve},
  author={Jeffrey Armstrong and Maher Ahmed and Siu-Cheung Chau},
A novel approach to 2D shape representation which is invariant to the rotation is introduced. The proposed system determines how any given shape should be rotated depending on the principal axis of the image. After rotation, a space-filling curve is applied to obtain a 1D vector representation of the image. This vector is later compressed in order to obtain a very small 1D vector that adequately represents an image --- this is called the Shape Feature Vector (SFV). The system can import these… 

Alternative patterns of the multidimensional Hilbert curve

Large-scale image retrieval tests show that exploring the image feature space with an alternative way to the classical Hilbert curve can lead to improved image searching performances.



A region-based shape descriptor using Zernike moments

A View-Based 3D Object Shape Representation Technique

A novel approach to 3D shape representation and matching utilizing a set of shape representations for 2D views of the object that capitalizes on the localization preserving nature of the Hilbert space filling curve and the approximation capabilities of the Wavelet transform.

WARP: accurate retrieval of shapes using phase of Fourier descriptors and time warping distance

This work proposes a novel Fourier-based approach, called WARP, for matching and retrieving similar shapes, which exploits the phase of Fourier coefficients and the use of the dynamic time warping distance to compare shape descriptors.

Shape representation and classification using the Poisson equation

This work presents a novel approach that allows us to reliably compute many useful properties of a silhouette that assigns for every internal point of the silhouette a value reflecting the mean time required for a random walk beginning at the point to hit the boundaries.

Retrieval by Shape Similarity with Perceptual Distance and Effective Indexing

This paper proposes retrieval by shape similarity using local descriptors and effective indexing, and presents a comparative analysis of different indexing structures, for shape retrieval.

Shape matching and object recognition using shape contexts

This paper presents work on computing shape models that are computationally fast and invariant basic transformations like translation, scaling and rotation, and proposes shape detection using a feature called shape context, which is descriptive of the shape of the object.

Shape representation and description using the Hilbert curve

Region-based shape representation and similarity measure suitable for content-based image retrieval

The shape retrieval performance of the proposed approach to shape representation and similarity measure is better than that of the more established Fourier descriptor method.