Christophe Rigaud

• Ph.D. in Computer Science
• PostDoc Position at ComixAI by DeMarque group & La Rochelle Université

This work explores how to fine-tune large language models using prompt engineering techniques with contextual information for generating an accurate text description of the full story, ready to be forwarded to off-the-shelve speech synthesis tools. We propose to use existing computer vision and optical character recognition techniques to build a gr...

The paper describes the “Multimodal Emotion Recognition on Comics scenes” competition presented at the ICDAR conference 2021. This competition aims to tackle the problem of emotion recognition of comic scenes (panels). Emotions are assigned manually by multiple annotators for each comic scene of a subset of a public large-scale dataset of golden ag...

In this paper, we introduce a new pipeline to learn manga character features with visual information and verbal information in manga image content. Combining these set of information is crucial to go further into comic book image understanding. However, learning feature representations from multiple modalities is not straightforward. We propose a m...

Comics and manga text recognition are attracting an increasing research and industrial interest. Also, the state of the art text detection and OCR performances is starting to be mature enough to provide automatic text recognition for a variety of comics and manga writing styles. However, comics text layout sometimes prevents usual text line detecti...

Learning with incomplete labels in Neural Networks has been actively investigated these last years. Among different kinds of incomplete labels, we investigate incomplete pixel-level labels which are tackled in many concrete problems. One of the challenges for incomplete pixel-level labels is the missing information at local-level. Most of the curre...

Comic book image analysis methods often propose multiple algorithms or models for multiple tasks like panel and character (body and face) detection, balloon segmentation, text recognition, etc. In this work, we aim to reduce the processing time for comic book image analysis by proposing one model that can learn multiple tasks called Comic MTL inste...

The digital comic book market is growing every year now, mixing digitized and digital-born comics. Digitized comics suffer from a limited automatic content understanding which restricts online content search and reading applications. This study shows how to combine state-of-the-art image analysis methods to encode and index images into an XML-like...

Graph-based representations are the most powerful data structures for extracting, representing and preserving the structural information of underlying data. Subgraph spotting is an interesting research problem, especially for studying and investigating the structural information based content-based image retrieval (CBIR) and query by example (QBE)...

Comics and manga are one of the most popular and familiar forms of graphic content over the world and play a major role in spreading country’s culture. Nowadays, massive digitization and digital-born materials allow page-per-page mobile reading but we believe that other usages may be released in the near future. In this paper, we focus on speech ba...

Speech text in comic books is placed and written in a particular manner by the letterers which raises unusual challenges for text recognition. We first detail these challenges and present different approaches to solve them. We compare the performances of generic versus specifically trained OCR systems for typewritten and handwritten text lines from...

Since the beginning of the twenty-first century, the cultural industry has been through a massive and historical mutation induced by the rise of digital technologies. The comic books industry keeps looking for the right solution and has not yet produced anything as convincing as the music or movie have. A lot of energy has been spent to transfer pr...

Document analysis is an active field of research, which can attain a complete understanding of the semantics of a given document. One example of the document understanding process is enabling a computer to identify the key elements of a comic book story and arrange them according to a predefined domain knowledge. In this study, we propose a knowled...

In this thesis, we review, highlight and illustrate the challenges related to comic book image analysis in order to give to the reader a good overview about the last research progress in this field and the current issues. We propose three different approaches for comic book image analysis that are composed by several processing. The first approach...

Comic books digitization combined with subsequent comic book understanding give rise to a variety of new applications, including content reflowing, mobile reading and multi-modal search. Document understanding in this domain is challenging as comics are semi-structured documents, with semantic information shared between the graphical and textual pa...

Graphs are popular data structures used to model pair wise relations between elements from a given collection. In image processing, adjacency graphs are often used to represent the relations between segmented regions. The comparison of such graphs has been largely studied but graph matching strategies are essential to find, efficiently, similar pat...

Les bandes dessinées représentent un patrimoine cultu-rel important dans de nombreux pays et leur numérisation massive offre la possibilité d'effectuer des recherches dans le contenu des images. À ce jour, ce sont principalement les structures des pages et leurs contenus textuels qui ont été étudiés, peu de travaux portent sur le contenu graphique....

Human detection in computer vision field is an active field of research. Extending this to human-like drawings such as the main characters in comic book stories is not trivial. Comics analysis is a very recent field of research at the intersection of graphics, texts, objects and people recognition. The detection of the main comic characters is an e...

Comic books constitute an important cultural heritage asset in many countries. Digitization combined with subsequent comic book understanding would enable a variety of new applications, including content-based retrieval and content retargeting. Document understanding in this domain is challenging as comics are semi-structured documents, combining s...

We present eBDtheque, a database of various comic book images and their ground truth for panels, balloons and text lines plus semantic annotations. The database consists of a hundred pages of various comic book albums, Franco-Belgian, American comics and mangas. Additionally, we present the piece of software used to establish the ground truth and a...

Comic books digitization combined with subsequent comic book understanding create a variety of new applications, including mobile reading and data mining. Document understand- ing in this domain is challenging as comics are semi-structured documents, combining semantically important graphical and textual parts. In this work we detail a novel approa...

Graphs are popular data structures used to model pair wise relations between elements from a given collection. In image processing, adjacency graphs are often used to represent the relations between segmented regions. Such graphs can be compared but graph matching strategies are essential to find similar pat- terns. In this paper, we propose to det...

Comic books constitute an important cultural heritage asset in many countries. Digitization combined with subsequent document understanding enable direct content-based search as opposed to metadata only search (e.g. album title or author name). Few studies have been done in this direction. In this work we detail a novel approach for the automatic t...

Les bandes dessinées représentent un patrimoine culturel important dans de nombreux pays. La numérisation en masse offre l'opportunité d'effectuer des recherches sur le contenu des albums et pas uniquement sur des métadonnées associées (e.g. nom de l'auteur ou de la collection). Peu de travaux ont été menés à ce jour. Seule l'extraction des cases e...

Comic books constitute an important heritage in many countries. Nowadays, digitization allows to search directly from content instead of metadata only (e.g. album title or author name). Few studies have been done in this direction. Only frame and speech balloon extraction have been experimented in the case of simple page structure. In fact, the pag...