Method for transmitting data on a viewable portion of a video signal

A method of superimposing data on the visible portion of a video signal comprising the steps of:

• (a) converting an input video signal to a digital representation thereof to define a plurality of sequential fields;
• (b) for each of a multiplicity of data symbols, assigning a respective chip pattern having more chips than the number of bits represented by said each data symbol, each chip pattern having a plurality of lines, each with a plurality of chips, to be superimposed on said video signal in paired lines having respective normal and inverse forms said chip pattern extending over more than one field;
• (c) developing a chip amplitude table having digital values that represent the values of respective chips to be superimposed on said video signal at corresponding positions thereof;
• and
• (d) generating an output video signal from the digital representation of said input video signal and the chip values represented in said chip amplitude table at the corresponding positions thereof.

A method of superimposing data on the visible portion of a video signal comprising the steps of:

• (a) for each of a multiplicity of data symbols, assigning a respective chip pattern having more chips than the number of bits represented by said each data symbol, each chip pattern having a plurality of lines, each with a plurality of chips, to be superimposed on said video signal in paired lines having respective normal and inverse forms;
• (b) generating a data carrying parameter based on said vide signal, said parameter having several sequential values for each of said chips;
• (c) modulating an amplitude of said chips in accordance with said parameter;
• (d) developing a composite digital representation of said video signal and the chip pattern corresponding to the data symbols to be superimposed on said video signal;
• and
• (e) generating a video signal from said composite digital representation.

A method of decoding data represented in the visible portion of a video signal, said video signal including for each of a multiplicity of data symbols a corresponding chip pattern having more chips than the number of bits represented by the respective data symbol, each chip pattern having a plurality of lines each with a plurality of chips superimposed on said video signal arranged in paired lines having respective normal and inverse forms each chip having an amplitude which is not necessarily intact through the duration of the chip;

• comprising the steps of:
• (a) deriving an integrated chip value for each position in each pair of lines in the lines representing a chip pattern corresponding to a single data symbol;
• (b) correlating the integrated chip values derived for a single data symbol with all chip patterns corresponding to respective ones of said multiplicity of data symbols;
• and
• (c) identifying the data symbol represented in the visible portion of said video signal in accordance with that chip pattern having the highest correlation with said data symbol.

A method of encoding data in the visible portion of a transmitted video signal without degrading display of the received video signal and for decoding said data in the received video signal, comprising the steps of:

• (a) selecting for a group of data bits to be transmitted an associated one of a number of longer predetermined PN sequences of chips;
• (b) dividing the selected PN sequence of chips into a multiplicity of lines of chips, said multiplicity of lines exceeding the number of lines determining a video field, each said line having more than one chip;
• (c) embedding each line of chips and its inverse, in pairwise fashion, in respective pairs of line scans of said video signal prior to its transmission,
• (d) operating on received pairs of line scans to detect the lines of chips represented thereby,
• (e) correlating each of said number of chip sequences with said detected line of chips to derive a correlation magnitude therefor, and
• (f) selecting the chip sequence with the largest correlation magnitude as the chip sequence that was transmitted.

A method of decoding data represented in the visible portion of a video signal, said video signal including for each of a multiplicity of data symbols a corresponding chip pattern having more chips than the number of bits represented by the respective data symbol, each chip pattern having a plurality of lines each with a plurality of chips superimposed on said video signal arranged in paired lines having respective normal and inverse forms each chip having an amplitude which is not necessarily intact through the duration of the chip;

• comprising the steps of:
• (a) deriving an integrated chip value for each position in each pair of lines in the lines representing a chip pattern corresponding to a single data symbol;
• (b) correlating the integrated chip values derived for a single data symbol with all chip patterns corresponding to respective ones of said multiplicity of data symbols;
• (c) identifying the data symbol represented in the visible portion of said video signal in accordance with that chip pattern having the highest correlation with said data symbol;
• and
• (d) providing a plurality of test arrays with test values, and using said test values to assign a pattern for each chip.

A method of encoding data in the visible portion of a transmitted video signal without degrading display of the received video signal and for decoding said data in the received video signal, comprising the steps of:

• (a) selecting for a group of data bits to be transmitted an associated one of a number of longer predetermined PN sequences of chips;
• (b) dividing the selected PN sequence of chips into a multiplicity of lines of chips, said multiplicity of lines exceeding the number of lines determining a video field, each said line having more than one chip;
• (c) embedding each line of chips and its inverse, in pairwise fashion, in respective pairs of line scans of said video signal prior to its transmission,
• (d) operating on received pairs of line scans to detect the fines of chips represented thereby,
• (e) correlating each of said number of chip sequences with said detected line of chips to derive a correlation magnitude therefor, and
• (f) selecting the chip sequence with the largest correlation magnitude as the chip sequence that was transmitted;
• wherein each line scan is operated upon in step (d) by deriving an integration function for each chip, and each chip function for one line scan is subtracted from a chip function for a correspondingly positioned chip in the paired line scan.