{'fraction_non_alphanumeric': 0.010477299185098952, 'fraction_numerical': 0.0, 'mean_word_length': 5.099290780141844, '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}}
Visual Navigation By Tracking Of Environmental Points

An observer can facilitate the computation of Egomotion parameters by tracking a point in the environment. The optical flow field generated by the tracking motion is analyzed for a translating and rotating observer. It is assumed that the observer tracks accurately, without significant slippage. In this case the constraint on the egomotion parameters due to the optical flow field is much simpler than that for the non tracking case. A principal advantage of the proposed scheme is that the computational process does not need to know the tracking velocity. The present method provides a mathematical formulation for the problem, which was also addressed in a qualitative way by researchers such as Cutting. A simple algebraic analysis determines when the parameters of motion can be computed uniquely.