Spectral watermarking for motion picture image data

A copy protection method for projecting, within a visually observable displayed motion picture work substantially invisible patterns, the method comprising:

• (a) illuminating a display area featuring said motion picture work with ultraviolet light to obscure images of the motion picture work to recording by a video camera having sensitivity to ultraviolet light and/or infrared light;
• and
• (b) illuminating a display area featuring said motion picture work with infrared light to obscure images of the motion picture work to recording by said video camera.

A copy-deterrent method of providing a marking of a visibly observable motion picture work that is projected onto a display surface, the method comprising:

• (a) displaying a first substantially invisible pattern on said display surface, said first substantially invisible pattern illuminated using infrared light during display of the motion picture work;
• and
• (b) displaying a second substantially invisible pattern on said display surface, said second substantially invisible pattern illuminated using ultraviolet light during display of the motion picture work.

A method of providing copy deterrence of a visually observable displayed motion picture work, the method comprising an ordered repetition of the following steps for each frame of at least a substantial number of frames of the displayed motion picture work:

• (a) projecting, in said each frame of said displayed motion picture work, a first substantially invisible pattern, said first substantially invisible pattern formed using light emitted at wavelengths outside the visible spectrum;
• and
• (b) projecting, in a next frame of said displayed motion picture work, a second substantially invisible pattern, said second substantially invisible pattern formed using light emitted at wavelengths outside the visible spectrum, whereby said second substantially invisible pattern is deliberately different in shape and/or intensity and/or position from said first substantially invisible pattern, so that an algorithm predicting motion from said each frame to said next frame is thereby rendered less efficient in recording the projected image of the displayed motion picture work.