Proceedings ArticleDOI
Location-Directed Image Modeling and its Application to Image Interpolation
Lantao Yu,Michael T. Orchard +1 more
- pp 2192-2196
TLDR
This paper explores the development and the use of a complex-valued, multi-resolution image representation to model and exploit local image structures in image-processing applications and produces PSNR results that are competitive with state-of-the-art single image interpolation algorithms around edges and preserves both edge sharpness and contour smoothness.Abstract:
This paper explores the development and the use of a complex-valued, multi-resolution image representation to model and exploit local image structures in image-processing applications Our approach distinguishes itself from prior approaches by constructing and exploiting the direct relationship between the locations of local structures and representation coefficients Coefficients of our representation have magnitudes that measure the image energy within a specific region in both space and frequency, and phases that carry information about the distance of that energy from a local reference position Our work proposes to model relationships, both across spatial regions and across different frequency bands, among the field of coefficient magnitudes, and among the field of coefficient phases To illustrate the advantages of modeling these relationships, we present an algorithm for interpolating a natural image by a factor of two, both horizontally and vertically Relationships among magnitudes and phases of available bands of coefficients are exploited to estimate local edge parameters (eg location, orientation, sharpness) that provide information about higher-frequency coefficients that are not available in the original image Our work produces PSNR results that are competitive with state-of-the-art single image interpolation algorithms around edges and preserves both edge sharpness and contour smoothnessread more
Citations
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Proceedings ArticleDOI
When Spatially-Variant Filtering Meets Low-Rank Regularization: Exploiting Non-Local Similarity for Single Image Interpolation
Lantao Yu,Michael T. Orchard +1 more
TL;DR: This paper proposes to build a carefully designed spatially-variant, non-local filtering scheme to generate a reliable estimate of the interpolated image and utilize NLR to refine the estimation.
Proceedings ArticleDOI
Accurate Edge Location Identification Based on Location-Directed Image Modeling
Lantao Yu,Michael T. Orchard +1 more
TL;DR: This paper introduces a new approach for determining accurate locations of edges in natural images based on a location-directed image modeling framework that exploits the linear phase-location characteristics in a complex-valued image representation, which guarantees even minuscule location variation be captured by changes in phases.
Posted Content
Manifold-Inspired Single Image Interpolation
TL;DR: Zhang et al. as discussed by the authors proposed to use the aliasing-removed image to guide the initialization of the interpolated image and develop a progressive scheme to refine the image based on manifold models, which enables reliable identification of similar patches even in the presence of strong aliasing.
Proceedings ArticleDOI
CTTSR: A Hybrid CNN-Transformer Network for Scene Text Image Super-Resolution
Kaiwei Dai,Li Kuang +1 more
TL;DR: In this article , a CNN-Transformer Text Super Resolution Network (CTTSR) is proposed to capture the semantic features of text images by the multi-head attention mechanism of the transformer.
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