Methods and apparatus to perform symbol-based watermark detection

An apparatus comprising:

• memory;
• and
• processor circuitry to execute machine readable instructions to at least:
• determine a first rate of occurrence of a first potential symbol value within a history of potential symbol values corresponding to a first symbol within a watermark;
• determine a second rate of occurrence of a second potential symbol value within the history of potential symbol values corresponding to the first symbol within the watermark;
• select one of the first potential symbol value or the second potential symbol value with a larger rate of occurrence as a likely symbol value;
• in response to a determination that the first rate of occurrence of the first potential symbol value equals the second rate of occurrence of the second potential symbol value:
• determine a first accumulated signal to noise ratio value corresponding to occurrences of the first potential symbol value;
• determine a second accumulated signal to noise ratio value corresponding to occurrences of the second potential symbol value;
• and
• select one of the first potential symbol value or the second potential symbol value with a larger accumulated signal to noise ratio value as the likely symbol value;
• and
• concatenate the likely symbol value with other likely symbol values corresponding to other symbols of the watermark to detect the watermark.

An apparatus comprising:

• means for determining a first rate of occurrence of a first potential symbol value within a history of potential symbol values corresponding to a first symbol within a watermark, the means for determining to determine a second rate of occurrence of a second potential symbol value within the history of potential symbol values corresponding to the first symbol within the watermark;
• first means for selecting one of the first potential symbol value or the second potential symbol value with a larger rate of occurrence as a likely symbol value;
• means for calculating, in response to a determination that the first rate of occurrence of the first potential symbol value equals the second rate of occurrence of the second potential symbol value, a first accumulated signal to noise ratio value corresponding to occurrences of the first potential symbol value, the means for calculating to determine a second accumulated signal to noise ratio value corresponding to occurrences of the second potential symbol value;
• second means for selecting one of the first potential symbol value or the second potential symbol value with a larger accumulated signal to noise ratio value as the likely symbol value;
• and
• means for concatenating concatenate the likely symbol value with other likely symbol values corresponding to other symbols of the watermark to detect the watermark.

An apparatus comprising:

• memory;
• and
• processor circuitry to execute machine readable instructions to at least:
• determine a first count of occurrences of a first potential symbol value within a history of potential symbol values corresponding to a first symbol within a watermark;
• determine a second count of occurrences of a second potential symbol value within the history of potential symbol values corresponding to the first symbol within the watermark;
• in response to a comparison of the first count of occurrences and the second count of occurrences:
• determine a first accumulated signal to noise ratio value corresponding to occurrences of the first potential symbol value;
• determine a second accumulated signal to noise ratio value corresponding to occurrences of the second potential symbol value;
• and
• select one of the first potential symbol value or the second potential symbol value having a greatest accumulated signal to noise ratio value as a likely symbol value;
• and
• concatenate the likely symbol value with other likely symbol values corresponding to other symbols of the watermark to detect the watermark.

An apparatus comprising:

• first means for determining a first count of occurrences of a first potential symbol value within a history of potential symbol values corresponding to a first symbol within a watermark, the means for determining to determine a second count of occurrences of a second potential symbol value within the history of potential symbol values corresponding to the first symbol within the watermark;
• second means for determining to, in response to a comparison of the first count of occurrences and the second count of occurrences, determine a first accumulated signal to noise ratio value corresponding to occurrences of the first potential symbol value, and determine a second accumulated signal to noise ratio value corresponding to occurrences of the second potential symbol value;
• means for selecting one of the first potential symbol value or the second potential symbol value with a larger accumulated signal to noise ratio value as a likely symbol value;
• and
• means for concatenating the likely symbol value with other likely symbol values corresponding to other symbols of the watermark to detect the watermark.