{'fraction_non_alphanumeric': 0.021464646464646464, 'fraction_numerical': 0.005050505050505051, 'mean_word_length': 5.720338983050848, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Image post-processing of a quad-head combined aerial camera and its surveying application

A quad-head combined aerial camera is first introduced in this paper. Due to its multiple center projection at each exposure station, an image post-processing procedure including camera calibration, matching, self-calibration stitching and color balancing is proposed to generate the stitched virtual image, in which the mathematical models of geometric calibration and self-calibration algorithms are primarily derived. The experiments show that the post-processing procedure has been capable of obtaining satisfying stitched virtual images. Besides, the related precisions of a 1:500 scale photogrammetry project has totally meet the requirements of national specifications of surveying and mapping.