Graph Neural Networks and Representation Embedding for Table Extraction in PDF Documents

Tables are widely used in several types of documents since they can bring important information in a structured way. In scientific papers tables can sum up novel discoveries and summarize experimental results, making the research comparable and easily understandable by scholars. Several methods perform table analysis working on document images, losing useful information during the conversion from the PDF files since OCR tools can be prone to errors, in particular for text inside tables. The main contribution of this work is to tackle the problem of table extraction, exploiting Graph Neural Networks. Moreover, node features are enriched with suitably designed representation embeddings. These representations allow to better distinguish not only tables from the other parts of the paper, but also table cells from table headers. We experimentally evaluated the proposed approach on a new dataset obtained by merging the information provided in the PubLayNet and PubTables-1M datasets.