The growing number of text detection approaches proposed in the literature requires a rigorous performance evaluation and ranking. An evaluation protocol relies on three elements: a reliable text reference, a matching strategy and finally a set of metrics. The few existing evaluation protocols often lack accuracy either due to inconsistent matching or due to unrepresentative metrics. In this thesis we propose a new evaluation protocol that tackles most of the drawbacks faced by currently used evaluation methods. This work is focused on three main contributions: firstly, we introduce a complex text reference representation that does not constrain text detectors to adopt a specific detection granularity level or annotation representation; secondly, we propose a set of matching rules capable of evaluating any type of scenario that can occur between a text reference and a detection; and finally we show how we can analyze a set of detection results, not only through a set of metrics, but also through an intuitive visual representation. A frequent challenge for many Text Understanding Systems is to tackle the variety of text characteristics in born-digital and natural scene images for which current OCRs are not well adapted. For example, texts in perspective are frequently present in real-word images because the camera capture angle is not normal to the plane containing the text regions. Despite the ability of some detectors to accurately localize such text objects, the recognition stage fails most of the time. In this thesis we also propose a rectification procedure capable of correcting highly distorted texts evaluated on a very challenging dataset.

EXPLOR_STEP=$WICRI_ROOT/Ticri/CIDE/explor/OcrV1/Data/Main/Exploration

HfdSelect -h $EXPLOR_STEP/biblio.hfd -nk 000013 | SxmlIndent | more

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{{Explor lien
   |wiki=    Ticri/CIDE
   |area=    OcrV1
   |flux=    Main
   |étape=   Exploration
   |type=    RBID
   |clé=     Hal:tel-01318351
   |texte=   Improvement of a text detection chain and the proposition of a new evaluation protocol for text detection algorithms
}}