In this paper, we introduce a large-scale multimodal publicly available dataset1 for the French political content analysis and fact-checking. This dataset consists of more than 1,200 fact-checked claims that have been scraped from a fact-checking service with associated metadata. For the video counterpart, the dataset contains nearly 6,730 TV programs, having a total duration of 6,540 hours, with metadata. These programs have been collected during the 2022 French presidential election with a dedicated workstation.

A system for the real-time copy detection of live TV videos is presented. A TV workstation supports the real-time and multichannel processing. Real-time NCC features are used for matching. A key-frame selection method ensures the robustness, the response and processing time optimization. Experiments are reported for time processing and accuracy on a public dataset against competitive methods.

This paper concentrates on developing an effective approach for decompressing JPEG document images. Our main goal is targeted to time-critical applications, especially to those situated on mobile network infrastructures. To this aim, the proposed approach is designed to work either in the transform domain or image spatial plane. Specifically, the image blocks are first classified into smooth blocks (e.g., background and uniform regions) and non-smooth blocks (e.g., text, graphics, and line-drawings). Next, the smooth blocks are fully decoded in the transform domain by minimizing the total block boundary variation, which is very efficient to compute. For decoding non-smooth blocks, a novel text model is presented that accounts for the specifics of document content. In addition, an efficient optimization algorithm is introduced to reconstruct the non-smooth blocks. The proposed approach has been validated by extensive experiments, demonstrating a significant improvement of visual quality, assuming that document images have been encoded at low bit rates and thus are subject to severe distortion.

In this paper, a complete logo detection/ recognition system for document images is proposed. In the proposed system, first, a logo detection method is employed to detect a few regions of interest (logo-patches), which likely contain the logo(s), in a document image. The detection method is based on the piece-wise painting algorithm (PPA) and some probability features along with a decision tree. For the logo recognition, a template based recognition approach is proposed to recognize the logo which may present in every detected logo-patch. The proposed logo recognition strategy uses a search space reduction technique to decrease the number of template logo-models needed for the recognition of a logo in a detected logo-patch. The features used for search space reduction are based on the geometric properties of a detected logo-patch. Based on our experimentations on 1290 document images of Tobacco800 dataset, 99.31% of the logos were detected as logo-patches. Among the detected logo-patches 97.90% of logos were fairly recognized. Considering both logo detection and recognition results, 97.22% of the logos in the document images could truly be detected/recognized as the overall performance of the proposed system.

Template matching is a technique used in classifying an object by comparing portions of images with another image. Finding a given template in an image is typically performed by scanning the image and evaluating the similarity with the template. When the scanning is concerned with the entire image template matching is optimal. This paper considers a special case of template matching where the templates are binary. Although binary template matching has been studied extensively since the early days of pattern recognition, this technique seems not longer in use in Document Image Analysis (DIA). The major reasons arête time complexity, the no-invariance to scale and rotation and the lack of adaptability of similarity measures. However, different contributions have been investigated during the last years to improve these aspects: robustness and discrimination capability of similarity measures, their characterization, time-processing optimization with hardware support, etc. In this paper, we will review first some of the recent issues about binary template matching. We will present then a system exploiting bitwise operators and parallel processing supporting fast and accurate binary template matching for Manga copyright protection. This system is compared to a FFT-based template matching, and it outperforms both in processing-time and detection accuracy.

In this paper, a coarse-to-fine logo detection scheme for document images is proposed. At the coarse level of the proposed scheme, content of a document image is pruned utilizing a decision tree and a small number of features such as frequency probability (FP), Gaussian probability (GP), height, width, and average density computed for patches. The patches are extracted employing the piece-wise painting algorithm (PPA) used for text-line segmentation. The fine level of the proposed scheme refines the detection results by integrating shape context descriptors and a Nearest Neighbor (NN) classifier. We evaluated the proposed approach using a public and two large industrial datasets. From the experiment on Tobacco-800 dataset, the best precision and accuracy of 75.25% and 91.50% were obtained respectively.

This paper presents a new approach for symbol localization in line-drawing images using junction features and geometry consistency checking. The proposed system first detects junction points, and then characterizes them by very compact, distinctive, and varying-length descriptors. The detected junctions are used to decompose a document image into a set of smooth primitives composing of isolated shapes (e.g., isolated circles and straight lines) and curve segments bounded between either two junctions or a junction and an end-point. These primitives are then associated with a new set of key points to form a complete and compact representation of a graphical document. Next, key point matching is performed to find the correspondences among the key points of the query and those of database documents. The obtained matches are finally refined by a new and efficient algorithm to deal with the problem of geometry consistency checking. Our experiments showed that the proposed system is very time- and memory-efficient, and provides high accuracy rate of symbol localization.

In this paper, we propose a new method to detect local interest points as junctions in line-drawing images. Our approach takes advantages of different aspects. Firstly, we extract skeleton of image and then construct a Skeleton Connective Graph with the expectation that it provides a first level of junction detection from shapes. Secondly, instead of employing low-level operators to detect junctions as described in many traditional techniques, our method works at path level taking different skeleton branches into account to gain robustness. Thirdly, we exploit the benefits of wavelet transform (e.g. multi-resolution analysis, discontinuity detection, fast computation, less sensitive to noises) to efficiently detect the dominant points from 1D representations of the paths. Finally, a post-process of pruning and connecting the skeleton segments is performed to discard false detected points and to refine the skeleton. We present in experiments interesting results compared to different methods.

This paper presents a new approach for logo detection exploiting contour based features. At first stage, pre-processing, contour detection and line segmentation are done. These processes result in set of Outer Contour Strings (OCSs) describing each graphics and text parts of the documents. Then, the logo detection problem is defined as a region scoring problem. Two types of features, coarse and finer ones, are computed from each OCS. Coarse features catch graphical and domain information about OCSs, such as logo positions and aspect ratios. Finer features characterize the contour regions using a gradient based representation. Using these features, we employ regression fitting to score how likely an OCS takes part of a logo region. A final step of correction helps with the wrong segmentation cases. We present experiments done on the Tobacco-800 dataset, and compare our results with the literature. We obtain interesting results compared to the best systems.

This paper deals with the topic of the retrieval of document images focused on a specific application: the ornaments of the Hand-Press period. It presents an overview as a result of the work and the discussions undertaken by a workgroup on this subject. The paper starts by giving a general view about digital libraries of ornaments and associated retrieval problematics. Two main issues are underlined:content based image retrieval (CBIR) and image difference visualization. Several contributions are summarized,commented and compared. Conclusions and open problems arising from this overview are twofold: 1. contributions on CBIR miss scale-invariant methods and don't provide significative evaluation results. 2. robust registration is the open problem for visual comparison.

In this paper, we present a scheme towards the segmentation of English multi-oriented touching strings into individual characters. When two or more characters touch, they generate a big cavity region at the background portion. Using Convex Hull information, we use these background information to find some initial points to segment a touching string into possible primitive segments (a primitive segment consists of a single character or a part of a character). Next these primitive segments are merged to get optimum segmentation and dynamic programming is applied using total likelihood of characters as the objective function. SVM classifier is used to find the likelihood of a character. To consider multi-oriented touching strings the features used in the SVM are invariant to character orientation. Circular ring and convex hull ring based approach has been used along with angular information of the contour pixels of the character to make the feature rotation invariant. From the experiment, we obtained encouraging results.

This paper deals with the topic of performance evaluation of the symbol recognition & spotting systems. It presents an overview as a result of the work and the discussions undertaken by a working group on this subject. The paper starts by giving a general view of symbol recognition & spotting and performance evaluation. Next, the two main issues of performance evaluation are discussed: groundtruthing and performance characterization. Different problems related to both issues are addressed: groundtruthing of real documents, generation of synthetic documents, degradation models, the use of a priori knowledge, mapping of the groundtruth with the system results, and so on. Open problems arising from this overview are also discussed at the end of the paper.

symbols on the documents. We have based our system on a combination of local and global structural approaches. The global approach groups the connected components together according to some closeness and connection constraints. The local approach splits up each connected component into a graph of geometrical objects (vectors, arcs, curves). The extracted graphs are matched thanks to a structural classifier, which permits graph-subgraph and exact-inexact matching. The system adaptability is obtained thanks to the scenarios use. A XML data representation is used, allowing the data manipulations and the graphic representations of results.