Enhanced table of contents (TOC) identifiers

• US 20070097802A1
• Filed: 10/27/2005
• Published: 05/03/2007
• Est. Priority Date: 10/27/2005
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Springer, Thomas, Polson, Michael
• Granted Patent: US 7,688,686 B2
• Time in Patent Office: Days
• US Class Current: 369/30.07
• CPC Class Codes: G11B 2220/2545 CDs
• CPC Class Codes: G11B 27/329 on a disc [VTOC]
• CPC Class Codes: G11B 7/00736 Auxiliary data, e.g. lead-in, lead-out, Power Calibration Area [PCA], Burst Cutting Area [BCA], control information sector headers or adresses in prepits G11B7/00745; address data in track wobble G11B7/24082

Abstract

A method for identifying the contents of a compact disc manipulating a received table of contents (TOC) identifier associated with the compact disc. The method parses portions of the TOC comprising a series of numbers corresponding to track offsets for each track of the compact disc. The method further determines the first number from the series of numbers, subtracts the first number from each number in the series of numbers to form an altered series of numbers, and concatenates the altered series of numbers to form an altered string that comprises the altered TOC identifier. The altered TOC identifier may then be compared to a plurality of canonical TOC identifiers to identify the contents of the compact disc. Another method generates a generic TOC identifier for a plurality of compact discs known to contain the same data.

Claims

1. A method for identifying the contents of a compact disc, said method comprising

receiving a table of contents (TOC) identifier associated with a compact disc, said TOC identifier comprising a string formed by the concatenation of a number indicative of the number of tracks on the compact disc, a series of numbers corresponding to track offsets for each track of the compact disc, and a number indicative of the lead out value of the tracks on the compact disc;

parsing said string into the number indicative of the number of tracks on the compact disc, the series of numbers corresponding to track offsets for each track of the compact disc, and a number indicative of the lead out value of the compact disc;

determining the first number from said series of numbers;

subtracting said first number from each number in said series of numbers to form an altered series of numbers;

concatenating said altered series of numbers to form an altered string that comprises the altered TOC identifier; and

comparing said altered TOC identifier to a plurality of canonical TOC identifiers, each of said canonical TOC identifiers associated with a particular album, to identify the contents of the compact disc.

2. A method as set forth in claim 1 further comprising rounding each of the numbers in the altered series of numbers before said concatenating and comparing.

3. A method as set forth in claim 2 wherein said rounding further comprises rounding up each of the numbers in the altered series of numbers before said concatenating and comparing.

4. A method as set forth in claim 2 wherein said rounding further comprises rounding an intertrack gap between each of the tracks to a value common with the intertrack gap of the canonical TOC identifiers.

5. A method as set forth in claim 1 wherein said receiving comprises receiving a TOC identifier from a user accessing the contents of the compact disc.

6. A method as set forth in claim 5 further comprising identifying the contents of the compact disc to the user.

7. A method as set forth in claim 6 wherein said identifying further comprises providing metadata associated with the compact disc to the user.

8. A method as set forth in claim 1 wherein said numbers are hexadecimal-based numbers.

9. A method as set forth in claim 8 further comprising converting the hexadecimal-based numbers of the TOC identifier to integer based numbers.

10. A method for generating a generic table of contents (TOC) identifier for a plurality of compact discs known to contain the same data, said generic TOC adapted for matching with a TOC identifier stored on an unknown compact disc for identifying the contents of the unknown compact disc, said method comprising:

collecting a plurality of TOC identifiers stored on a plurality of compact discs known to contain the same data, each of said TOC identifiers comprising a string formed by the concatenation of a number indicative of the number of tracks on the compact disc, a series of numbers corresponding to track offsets for each track of the compact disc, and a number indicative of the lead out value of the tracks on the compact disc;

parsing said string into the number indicative of the number of tracks on the compact disc, the series of numbers corresponding to track offsets for each track of the compact disc, and a number indicative of the lead out value of the compact disc;

aggregating each of the respective series of track offset numbers for each TOC identifier with the corresponding track offset numbers from the other of the plurality of collected TOC identifiers;

creating a track offset range for each track on said plurality of compact discs based upon said aggregated track offset population corresponding to each track; and

combining the track offset range for each track to create the generic TOC identifier.

11. A method as set forth in claim 10 wherein said creating a track offset range for each track comprises utilizing the standard deviation of each aggregated track offset population to determine each respective range.

12. A method as set forth in claim 10 further comprising comparing said plurality of TOC identifiers before said parsing;

identifying outlier TOC identifiers; and

removing the identified outlier TOC identifiers from said parsing and said aggregating.

13. A method as set forth in claim 12 wherein said identifying outlier TOC identifiers comprises identifying those TOC identifiers where the number indicative of the number of tracks on the compact disc is different than the mode of the number indicative of the number of tracks on the compact disc for the plurality of TOC identifiers.

14. A method as set forth in claim 10 wherein said creating a track offset range for each track further comprises super-sampling said aggregated track offset population.

15. A method as set forth in claim 14 wherein said creating further comprises super-sampling the aggregated track offset population at a level of granularity larger than the granularity of the collected individual TOC identifiers.

16. A method as set forth in claim 15 wherein said creating a track offset range for each track further comprises creating a track offset range for each track of at least about 2/15 of a second.

17. A method as set forth in claim 16 wherein said creating a track offset range for each track further comprises creating a track offset range for each track of at least about ⅓

of a second.

18. A method as set forth in claim 10 wherein said aggregating further comprises weighting one or more of said aggregated track offset numbers according to the popularity of the respective TOC identifier.

19. A method as set forth in claim 10 wherein said creating a track offset range for each track on said plurality of compact discs further comprises creating two or more offset ranges for one or more of said tracks based upon said aggregated track offset population corresponding to each track.

20. A method for altering a table of contents (TOC) identifier for a compact disc to create an altered TOC identifier which may be used to identify the contents of a compact disc, said TOC identifier comprising a string formed by concatenating a series of numbers together, each of said series of numbers corresponding to track offsets for each track on the compact disc, said method comprising:

parsing said string of the TOC identifier into said series of numbers;

determining the first number in said series of numbers;

subtracting said first number from each number in said series of numbers to form an altered series of numbers; and

concatenating said altered series of numbers to form an altered string that comprises the altered TOC identifier.