The invention discloses a
digital television timing charging and copyright protecting method based on watermarks. The
digital television timing charging and copyright protecting method comprises the following steps: 1) recording the starting time that a user watches a
digital television and the program information; 2) reading a PDK (
PERL Development Kit) in a
smart card by virtue of a bidirectional
set top box, enabling the PDK to generate
watermark signals, and carrying out the error correction of coding on the
watermark signals; 3) enabling the
watermark signals processed by the error correction of coding through a decoder at the time of decoding into the middle-
low frequency DCT coefficients of an I frame luminance component after the I frame is researched, and then outputting and playing the middle-
low frequency DCT coefficients; 4) billing the digital television by hours through a
user management system; 5) extracting watermarks of suspended illegal videos when the suspended illegal videos are played in the program of the digital television, and determining the copyright by utilizing the extracted watermark signals, and further judging the user illegally spreading programs of the digital television. The digital television timing charging and copyright protecting method disclosed by the invention has the advantages of novel and reasonable design, simplicity in operation, low cost, high accuracy in timing charging, and high popularization and application value, and also has the
advantage that the source of the
copyright infringement can be tracked. The digital television timing charging and copyright protecting method is suitable for the popularization and development of the digital television.