3D model AMBTC DFT Karhunen–Loève transform MIDI audibility bic Book Industry Communication::K Economics, finance, business & management::KN Industry & industrial studies::KNT Media, information & communication industries::KNTX Information technology industries block embedding blockchain capacity carrier file covert channel cryptographic hash function cryptography cyber terrorist networks cyber-criminality data hiding deep learning models detection digital copyright protection digital fingerprinting digital forensics digital rights management digital watermarking embedding capacity embedding efficiency file-size change-rate fragile watermarking genetic algorithm hash chain