ExTTNet: A Deep Learning Algorithm for Extracting Table Texts from Invoice Images
Adem Akdoğan, Murat Kurt
TL;DR
The paper presents ExTTNet, a deep learning solution for autonomously extracting product table text from invoice images. It combines OCR via Tesseract with engineered features and a multilayer neural network trained on an RTX $3090$, achieving a reported F1 score of $0.92$ on a held-out set. Evaluations show high precision and recall (≈$0.93$) and overall accuracy of $0.92$, validated on a dataset of $8794$ German invoices. The approach emphasizes token-level prediction of table elements rather than whole-table localization, enabling partial corrections and potential workflow savings in accounting. Future work aims to integrate richer image cues and advanced techniques to further enhance performance and robustness.
Abstract
In this work, product tables in invoices are obtained autonomously via a deep learning model, which is named as ExTTNet. Firstly, text is obtained from invoice images using Optical Character Recognition (OCR) techniques. Tesseract OCR engine [37] is used for this process. Afterwards, the number of existing features is increased by using feature extraction methods to increase the accuracy. Labeling process is done according to whether each text obtained as a result of OCR is a table element or not. In this study, a multilayer artificial neural network model is used. The training has been carried out with an Nvidia RTX 3090 graphics card and taken $162$ minutes. As a result of the training, the F1 score is $0.92$.
