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Context Tree-Based Image Contour Coding Using a Geometric Prior

Amin Zheng, Gene Cheung, Dinei Florencio
2017 IEEE Transactions on Image Processing  
MAP prevents us from overfitting given a small training set X of past symbol sequences by identifying a VCT T that achieves a high likelihood P(X|T) of observing X given T, and a large geometric prior  ...  To encode the symbol sequence using arithmetic coding, we compute an optimal variable-length context tree (VCT) T via a maximum a posterior (MAP) formulation to estimate symbols' conditional probabilities  ...  To code object contours of a Middleburry depth image, we used other Middleburry images to train the context tree.  ... 
doi:10.1109/tip.2016.2627813 pmid:27849536 fatcat:on4az4xwqvgkpb2aouikmibjnu

Joint Denoising/Compression of Image Contours via Shape Prior and Context Tree

Amin Zheng, Gene Cheung, Dinei Florencio
2018 IEEE Transactions on Image Processing  
using the decoded contours as input.  ...  We design a dynamic programming (DP) algorithm that solves the posed problem optimally, and propose a compact context representation called total suffix tree (TST) that can reduce complexity of the algorithm  ...  Prior Term Similarly to [4, 38] , we propose a geometric shape prior based on the assumption that contours in natural images tend to be more straight than curvy.  ... 
doi:10.1109/tip.2018.2816818 pmid:29641410 fatcat:2ctwhszfgjhxzmfo22kshrunxa

Multiscale geometric image processing

Justin K. Romberg, Michael B. Wakin, Richard G. Baraniuk, Touradj Ebrahimi, Thomas Sikora
2003 Visual Communications and Image Processing 2003  
As a first step towards accounting for this structure, we will show how to explicitly capture the geometric regularity of contours in cartoon images using the wedgelet representation and a multiscale geometry  ...  Wavelet based algorithms define the state-of-the-art for applications including image coding (JPEG2000), restoration, and segmentation.  ...  The model can be used as a prior distribution on the wedgelet orientations, and can be used as such in statistical image processing applications such as coding, denoising, and detection.  ... 
doi:10.1117/12.509903 fatcat:gcp3bvrpjjhivkyq4hqj466bty

Review of shape representation and description techniques

Dengsheng Zhang, Guojun Lu
2004 Pattern Recognition  
More and more images have been generated in digital form around the world. There is a growing interest in ÿnding images in large collections or from remote databases.  ...  Searching for images using shape features has attracted much attention. There are many shape representation and description techniques in the literature.  ...  use boundary information as in contour base methods.  ... 
doi:10.1016/j.patcog.2003.07.008 fatcat:zj6wwo5ptbeqrabstj24zka3ea

Automatic Building Detection in Aerial Images Using a Hierarchical Feature Based Image Segmentation

Mohammad Izadi, Parvaneh Saeedi
2010 2010 20th International Conference on Pattern Recognition  
A tree-based mechanism is utilized to inspect segmented regions using their spatial relationships with each other and their regional/geometrical characteristics.  ...  This paper introduces a novel automatic building detection method for aerial images. The proposed method incorporates a hierarchical multilayer feature based image segmentation technique using color.  ...  The building's context and geometrical features are used for local segmentation of image.  ... 
doi:10.1109/icpr.2010.123 dblp:conf/icpr/IzadiS10 fatcat:dr5kx5cwgjhjpjvccketwpaj3u

A Review of Visual Descriptors and Classification Techniques Used in Leaf Species Identification

K. K. Thyagharajan, I. Kiruba Raji
2018 Archives of Computational Methods in Engineering  
Images that look the same may deviate in terms of geometric and photometric variations.  ...  Key research areas in plant science include plant species identification, weed classification using hyper spectral images, monitoring plant health and tracing leaf growth, and the semantic interpretation  ...  Centroid Contour and Angle Code Descriptors The Centroid Contour Descriptor (CCD) used by Sangle et al.  ... 
doi:10.1007/s11831-018-9266-3 fatcat:xa4zxzfhjbgnhkv4h2xu5axhqy

Image partition boundary coding

Paul J. Ausbeck, Jr., Andrew G. Tescher
1998 Applications of Digital Image Processing XXI  
The new coding models are placed into context with previous pixel based work by the development a new categorization of image partition representations.  ...  A technique for determining the appropriate application domain of pixel based codes is developed.  ...  The two new codes are then compared to other image based codes on a synthetic geometric image rendered at various resolutions. Interpretation of the experiments and conclusions follow.  ... 
doi:10.1117/12.323195 fatcat:l7s3ih66crfslisuejql7o3i2y

A Novel Algorithm for Exact Concave Hull Extraction [article]

Kevin Christopher VanHorn, Murat Can Çobanoğlu
2022 arXiv   pre-print
We demonstrate significant improvements through context-dependent compression on disparate regions within a single image (entropy encoding for noisy and predictive encoding for the structured regions).  ...  Especially in the context of a uniform grid, concave hull algorithms are largely approximate, sacrificing region integrity for spatial and temporal efficiency.  ...  Microscopy images provided by multiple collaborators were also integral to the implementation and analysis of our technique.  ... 
arXiv:2206.11481v1 fatcat:z5zmgvnubrfrfodmkf437q2wja

Human Pose Estimation from Monocular Images: A Comprehensive Survey

Wenjuan Gong, Xuena Zhang, Jordi Gonzàlez, Andrews Sobral, Thierry Bouwmans, Changhe Tu, El-hadi Zahzah
2016 Sensors  
The first way clusters solutions based on whether the human pose estimation problem is modeled as geometric projection of a 3D real-world scene or if it is treated as a general classification/regression  ...  In geometric projection modeling (Section 4.1.2), a 3D human body model is required (Section 3.3) . Furthermore, camera parameters are required for a projection model.  ...  (a) The background image; (b) An original image; (c) The extracted silhouette from (b). Figure 4 . 4 Contour Features from [228]. (a) An original image; (b) Extracted contours.  ... 
doi:10.3390/s16121966 pmid:27898003 pmcid:PMC5190962 fatcat:jigvz4ovpbh63eovto3etoefx4

A review and an approach for object detection in images

Kartik Umesh Sharma, Nileshsingh V. Thakur
2017 International Journal of Computational Vision and Robotics  
This paper presents a review of the various techniques that are used to detect an object, localise an object, categorise an object, extract features, appearance information, and many more, in images and  ...  In order to detect an object in an image or a video the system needs to have a few components in order to complete the task of detecting an object, they are a model database, a feature detector, a hypothesiser  ...  Steiner tree-based approach can be developed to address this issue. For this purpose, a Steiner tree-based classifier can be used to classify the object(s) present in a particular image.  ... 
doi:10.1504/ijcvr.2017.10001813 fatcat:milusfamuzgv5js34ufqu2ujte

A review and an approach for object detection in images

Kartik Umesh Sharma, Nileshsingh V. Thakur
2017 International Journal of Computational Vision and Robotics  
This paper presents a review of the various techniques that are used to detect an object, localise an object, categorise an object, extract features, appearance information, and many more, in images and  ...  In order to detect an object in an image or a video the system needs to have a few components in order to complete the task of detecting an object, they are a model database, a feature detector, a hypothesiser  ...  Steiner tree-based approach can be developed to address this issue. For this purpose, a Steiner tree-based classifier can be used to classify the object(s) present in a particular image.  ... 
doi:10.1504/ijcvr.2017.081234 fatcat:n7wcnpafe5bw7klocovns33mye

3D tomographic reconstruction using geometrical models

Xavier L. Battle, Gregory S. Cunningham, Kenneth M. Hanson, Kenneth M. Hanson
1997 Medical Imaging 1997: Image Processing  
We use the system response of the University of Arizona Fast SPECT imager to illustrate this method by reconstructing the shape of a heart phantom.  ...  We demonstrate the usefulness of the approach and emphasize the techniques of designing forward and adjoint codes.  ...  We are indebted to Harry Barrett and Don Wilson of the University of Arizona for supplying us with their FASTSPECT measurement matrix and a suitable simulated phantom.  ... 
doi:10.1117/12.274121 fatcat:wndhecimjbe65dhdoy5prfl5py

Multi-modal RGB-D Image Segmentation from Appearance and Geometric Depth Maps

Isail Salazar, Said Pertuz, Fabio Martínez
2020 Tecno Lógicas  
Based on color images, a color segmentation tree (C-tree) is created to obtain segmented and over-segmented maps.  ...  This work presents a novel multi-modal segmentation strategy that integrates depth and appearance cues from RGB-D images by building a hierarchical region-based representation, i.e., a multi-modal segmentation  ...  This representation can be used to code geometrical planes into a segmentation input layer of the MM-tree process to better describe different scene perspectives.  ... 
doi:10.22430/22565337.1538 fatcat:kpyxyy5oivh6bai5kf6a6w65ua

Describing Colors, Textures and Shapes for Content Based Image Retrieval - A Survey [article]

Jamil Ahmad, Muhammad Sajjad, Irfan Mehmood, Seungmin Rho, Sung Wook Baik
2015 arXiv   pre-print
In this paper we will present a detailed overview of some of the powerful color, texture and shape descriptors for content based image retrieval.  ...  Content based image retrieval systems employing these features has proven very successful.  ...  A grid based approximation of the shape contour is obtained and then a 4-directional or 8directional chain code can be generated by traversing the approximated shape boundary.  ... 
arXiv:1502.07041v1 fatcat:ajzvorf3pnbxxe2e7f6syhsu3e

Segmentation of Soft atherosclerotic plaques using active contour models [article]

Muhammad Moazzam Jawaid
2016 arXiv   pre-print
Consequently based on detected seed point & intensity behaviour, localized active contour segmentation has been applied to extract complete coronary tree.  ...  Detection of non-calcified plaques in the coronary tree is a challenging problem due to the nature of comprising substances.  ...  [61] proposed to integrate shape prior into the geometric active contours framework. They proposed to apply a local shape filter representing geometric constraints as shown in figure 3.3.  ... 
arXiv:1608.00116v1 fatcat:5h6n3ervbze47b6oiit66ro4qq
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