Abstract
The Generalized Intersection over Union (GIoU) and the Manhattan distance between axis-aligned boxes represented either as corner coordinates or their center and size, are extended to accept a range of bounding boxes as ground truth, producing the metrics RIoU, $R_1$ and $R^t_1$, respectively. In the context of Table Detection it is shown that this box relaxation procedure allows training object detection models with partial or inexact annotations. For the Table Structure Recognition task, several code improvements to Microsoft's open-source Table Transformer increase all $\mathrm{GriTS}$ metrics on PubTables-1M, with the overall accuracy increasing from 0.8326 to 0.8433. Then box relaxation is applied to take advantage in the object detection loss function of the discretizing nature of the post-inference table cell matrix extraction procedure. This further reduces the error of the $\mathrm{GriTS}$ metrics $Acc_{Con}$, $GriTS_{Con}$, $GriTS_{Loc}$ and $GriTS_{Top}$ on the PubTables-1M tables without spanning cells by 1.8%, 13.2%, 10.6% and 14.9%, respectively.
Keywords
object detection
table detection
table structure recognition
bounding box regression
loss function
Data Availability Statement
The source code used to generate the results reported here is available under an open-source license at https://github.com/aioaneid/table-transformer. No new training data were collected for this study.
Funding
This work was supported without any funding.
Conflicts of Interest
The author declares no conflicts of interest.
Ethical Approval and Consent to Participate
Not applicable.
Cite This Article
APA Style
Aioanei, D. (2025). Relaxed Bounding Boxes for Object Detection. ICCK Journal of Image Analysis and Processing, 1(3), 107–124. https://doi.org/10.62762/JIAP.2025.507329
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