Method and system for protecting digital data from unauthorized copying

An apparatus for protecting data from unauthorized copying comprising:

• watermark inserter for embedding a watermark having a trigger signal into data to be protected to form watermarked data, said watermark and trigger signals being preserved during signal transformation;
• scrambler for scrambling said watermarked data;
• trigger extractor disposed for receiving said watermarked data and extracting said trigger signal from said watermark signal;
• and
• descrambler for descrambling said watermarked data when said extracted trigger signal has a predetermined value;
• where said scrambler divides said watermarked data into groups of watermarked data that are combined in said trigger extractor by means of a commutative process.

An apparatus for protecting data from unauthorized copying comprising:

• watermark inserter for embedding a watermark having a trigger signal into data to be protected to form watermarked data, said watermark and trigger signals being preserved during signal transformation;
• scrambler for scrambling said watermarked data;
• trigger extractor disposed for receiving said watermarked data and extracting said trigger signal from said watermark signal;
• and
• descrambler for descrambling said watermarked data when said extracted trigger signal has a predetermined value;
• where said scrambler reorders values within said groups of watermarked data.

An apparatus for protecting data from unauthorized copying comprising:

• watermark inserter for embedding a watermark having a trigger signal into data to be protected to form watermarked data, said watermark and trigger signals being preserved during signal transformation;
• scrambler for scrambling said watermarked data;
• trigger extractor disposed for receiving said watermarked data and extracting said trigger signal from said watermark signal;
• and
• descrambler for descrambling said watermarked data when said extracted trigger signal has a predetermined value;
• where said groups of watermarked data comprise blocks of watermarked data.