{'fraction_non_alphanumeric': 0.012510425354462052, 'fraction_numerical': 0.0, 'mean_word_length': 5.382978723404255, '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}}
An enhanced secure buyer-seller watermarking protocol

Digital watermarks are used to prevent unauthorized duplication and distribution of multimedia contents. This is achieved by inserting a unique digital watermark into each copy of the multimedia contents before it is sold to a buyer. If the buyer sells unauthorized copies of the watermarked content, then these deterred copies can be traced using a watermark extraction and detection algorithm. This paper proposes an enhanced buyer-seller watermarking protocol based on public key encryption standard, which is secure and flexible. Buyer places the purchase order to seller which will be forwarded to the certification authority using the existing public key and digital signature infrastructure. The trusted certification authority issues the watermark based on the buyer-seller public key, the watermark identification number, based on watermark and secret key, which enables the buyer to check the originality of the purchased digital content. This prevent the buyer from claiming that an unauthorized copy may have originated from the seller and gives highest privilege to the buyer to ensure the quality of the purchased digital content.