This dataset contains ground truth data for lines in AjMC commentaries. It is an addendum to the previously released PLA and OCR datasets, GT4HistCommentLayout and GT4HistComment. The dataset is released under the CC-BY 4.0 license.

The dataset is released as a single VIA 2 JSON file. The project can be open in VIA (project/load) or directly with JSON. Lines are annotated as rectangle regions, and can be very easily retrieved using:

import json

with open('GT-commentaries-lines.json') as f:
    data = json.load(f)

lines = {}
for page_id, page_dict in data['_via_img_metadata'].items():
    lines[page_id] = []
    for region in page_dict['regions']:
        lines[page_id].append(region['shape_attributes'])

# This outputs a dictionary in the form of: 
# {page_id: [line1, line2, ...], ...}
# where each line is a dictionary with the following keys:
# {'name': 'rect', 'x': x, 'y': y, 'width': w, 'height': h}

Notice that this dataset annotates the same images as GT4HistCommentLayout, so that images can be retrieved from there. This being said, copyrighted images are not included.

Notice that a balanced version of this dataset is also available, where lines are balanced across commentaries with a maximum of 40 pages and a minimum of 35 pages per commentaries. This is useful for training purposes, as it avoids biases towards commentaries with more lines. The balanced version is available in the file GT-commentaries-lines-balanced.json. It was generated using ajmc.olr.line_detection.data_processing.balance_dataset from the ajmc package.