{'fraction_non_alphanumeric': 0.019952114924181964, 'fraction_numerical': 0.0039904229848363925, 'mean_word_length': 5.741935483870968, '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}}
Psychophysical experiments for evaluating target distinctness in images

An experimental design has been developed to facilitate collection of data for developing and testing computational models for assessment of the perceptual similarity or difference of texture patterns. This experimental design is based on Thurstone's Law of Comparative Judgement. To facilitate consistency in presentation of stimuli, collection of data, and computation of psychological scale values, an X-windows testing environment has been developed called the X-based Perceptual Experiment Testbed (XPET). A pilot study was conducted utilizing this experimental design. The study utilized images in which targets and their associated background had uncorrelated Gaussian noise texture patterns. Thus, only first- order image statistics were of significance. Psychological scale values for `target distinctness' obtained using this experimental design were compared to several first-order image metrics. Correlation coefficients as high as 0.9881 were found between the psychological scale values and first-order image metrics. It has been concluded that this experimental design should be adequate for data collection to support development of new second-order image metrics.