Multimedia adaptive scrambling system (MASS)

A method for protecting digital samples of content from illicit use by scrambling the content, wherein each sample includes a plurality of bits, ranging from least significant bits (LSBs) to most significant bits (MSBs), comprising the steps of:

• determining a dynamic range defined by a most significant non-zero data bit of each sample;
• and
• adaptively selecting a number of LSBs to be scrambled in each sample according to the dynamic range determined therefor;
• scrambling the selected number of LSBs in each sample according to a scrambling key, while preserving a number of MSBs in each sample, to provide corresponding scrambled samples;
• wherein:
• the selected number of LSBs is scrambled in each sample such that the scrambled samples are degraded but still recognizable;
• and
• in said scrambling step, the selected number of LSBs are scrambled between different samples, and within the same sample, using inter-sample and intra-sample scrambling, respectively.

A method for protecting digital samples of content from illicit use by scrambling the content, wherein each sample includes a plurality of bits, ranging from least significant bits (LSBs) to most significant bits (MSBs), comprising the steps of:

• determining a dynamic range defined by a most significant non-zero data bit of each sample;
• and
• adaptively selecting a number of LSBs to be scrambled in each sample according to the dynamic range determined therefor;
• scrambling the selected number of LSBs in each sample according to a scrambling key, while preserving a number of MSBs in each sample, to provide corresponding scrambled samples;
• wherein:
• the selected number of LSBs is scrambled in each sample such that the scrambled samples are degraded but still recognizable;
• and
• in said scrambling step, the selected number of LSBs are scrambled between different samples using horizontal inter-sample scrambling by interchanging bits having the same weight.

A method for descrambling previously scrambled digital samples of content, wherein each sample includes a plurality of bits, ranging from least significant bits (LSBs) to most significant bits (MSBs), comprising the steps of:

• determining a dynamic range defined by a most significant non-zero data bit of each sample;
• and
• adaptively selecting a number of LSBs to be descrambled in each sample according to the dynamic range determined therefor;
• descrambling the selected number of LSBs in each sample according to a scrambling key, while preserving a number of MSBs in each sample, to provide corresponding descrambled samples;
• wherein:
• the selected number of LSBs is scrambled in each sample such that the scrambled samples are degraded but still recognizable.

A method for descrambling previously scrambled digital samples of content, wherein each sample includes a plurality of bits, ranging from least significant bits (LSBs) to most significant bits (MSBs), comprising the steps of:

• determining a dynamic range defined by a most significant non-zero data bit of each sample;
• and
• adaptively selecting a number of LSBs to be descrambled in each sample according to the dynamic range determined therefor;
• descrambling the selected number of LSBs in each sample according to a scrambling key, while preserving a number of MSBs in each sample, to provide corresponding descrambled samples;
• wherein:
• the selected number of LSBs is scrambled in each sample such that the scrambled samples are degraded but still recognizable;
• and
• in said descrambling step, the selected number of LSBs are descrambled between different samples, and within the same sample, using inter-sample and intra-sample descrambling, respectively.

A method for descrambling previously scrambled digital samples of content, wherein each sample includes a plurality of bits, ranging from least significant bits (LSBs) to most significant bits (MSBs), comprising the steps of:

• determining a dynamic range defined by a most significant non-zero data bit of each sample;
• and
• adaptively selecting a number of LSBs to be descrambled in each sample according to the dynamic range determined therefor;
• descrambling the selected number of LSBs in each sample according to a scrambling key, while preserving a number of MSBs in each sample, to provide corresponding descrambled samples;
• wherein:
• the selected number of LSBs is scrambled in each sample such that the scrambled samples are degraded but still recognizable;
• and
• in said descrambling step, the selected number of LSBs are descrambled between different samples using horizontal inter-sample descrambling by interchanging bits having the same weight.

An apparatus for protecting digital samples of content from illicit use by scrambling the content, wherein each sample includes a plurality of bits, ranging from least significant bits (LSBs) to most significant bits (MSBs), comprising:

• a range detector/mask generator for determining a dynamic range defined by a most significant non-zero data bit of each sample and adaptively selecting a number of LSBs to be scrambled in each sample according to the dynamic range thereof;
• a scrambler for scrambling the selected number of LSBs in each sample according to a scrambling key, while preserving a number of MSBs in each sample, to provide corresponding scrambled samples;
• wherein:
• the selected number of LSBs is scrambled in each sample such that the scrambled samples are degraded but still recognizable.

An apparatus for descrambling previously scrambled digital samples of content, wherein each sample includes a plurality of bits, ranging from least significant bits (LSBs) to most significant bits (MSBs), comprising:

• a range detector/mask generator for determining a dynamic range defined by a most significant non-zero data bit of each sample and adaptively selecting a number of LSBs to be descrambled in each sample according to the dynamic range thereof;
• a descrambler for descrambling the selected number of LSBs in each sample according to a scrambling key, while preserving a number of MSBS in each sample, to provide corresponding descrambled samples;
• wherein:
• the selected number of LSBs is scrambled in each sample such that the scrambled samples are degraded but still recognizable.