Digital data insertion apparatus and methods for use with compressed audio/video data

1. A method of generating ratings information, the method comprising:

inserting audience measurement data in a compressed bitstream by:

eliminating a first type of data within the compressed data bitstream;

packing a second type of data to occupy a location within the compressed data bitstream from which the first type of data is eliminated; and

inserting the audience measurement data in a predetermined location within the compressed data bitstream that is expanded as a result of the packing of the second type of data to form a modified compressed data bitstream; and

generating the ratings information based on the modified compressed data bitstream.

2. A method as defined in claim 1 , wherein generating the ratings information based on the modified compressed data bitstream includes:

generating program lineup information based on audience measurement data extracted at a first location;

generating consumption information based on audience measurement data at a second location; and

comparing the program lineup information to the consumption information to generate the ratings information.

3. A method as defined in claim 1 , wherein the compressed data bitstream includes at least an audio program or a video program.

4. A method as defined in claim 1 , wherein the first type of data includes a skip byte and the predetermined location is an auxiliary data field.

5. A method as defined in claim 1 , wherein the second type of data includes compressed audio content or compressed video content.

6. A method as defined in claim 1 , wherein the compressed data bitstream is AC-3 compliant.

7. A method as defined in claim 6 , further including re-computing cyclical redundancy check values for each AC-3 frame of the compressed data bitstream after inserting the audience measurement data in the predetermined location.

8. A system for generating ratings information, the system comprising:

a memory; and

a processor coupled to the memory, the processor to:

insert audience measurement data in a compressed bitstream by:

eliminating a first type of data within the compressed data bitstream;

packing a second type of data to occupy a location within the compressed data bitstream from which the first type of data is eliminated; and

inserting the audience measurement data in a predetermined location within the compressed data bitstream that is expanded as a result of the packing of the second type of data to form a modified compressed data bitstream; and

generate the ratings information based on the modified compressed data bitstream.

9. A system as defined in claim 8 , wherein the processor is to generate the ratings information based on the modified compressed data bitstream by:

generating program lineup information based on audience measurement data extracted at a first location;

generating consumption information based on audience measurement data at a second location; and

comparing the program lineup information to the consumption information to generate the ratings information.

10. A system as defined in claim 8 , wherein the compressed data bitstream includes at least an audio program or a video program.

11. A system as defined in claim 8 , wherein the first type of data includes a skip byte and the predetermined location is an auxiliary data field.

12. A system as defined in claim 8 , wherein the second type of data includes compressed audio content or compressed video content.

13. A system as defined in claim 8 , wherein the compressed data bitstream is AC-3 compliant.

14. A system as defined in claim 13 , wherein the processor is to re-compute cyclical redundancy check values for each AC-3 frame of the compressed data bitstream after inserting the audience measurement data in the predetermined location.

15. A machine readable storage device or storage disk comprising instructions that, when executed, cause a machine to at least:

insert audience measurement data in a compressed bitstream by:

eliminating a first type of data within the compressed data bitstream;

packing a second type of data to occupy a location within the compressed data bitstream from which the first type of data is eliminated; and

inserting the audience measurement data in a predetermined location within the compressed data bitstream that is expanded as a result of the packing of the second type of data to form a modified compressed data bitstream; and

generate the ratings information based on the modified compressed data bitstream.

16. A machine readable storage device or storage disk as defined in claim 15 , wherein the instructions, when executed, cause the machine to generate the ratings information based on the modified compressed data bitstream by:

generating program lineup information based on audience measurement data extracted at a first location;

generating consumption information based on audience measurement data at a second location; and

comparing the program lineup information to the consumption information to generate the ratings information.

17. A machine readable storage device or storage disk as defined in claim 15 , wherein the compressed data bitstream includes at least an audio program or a video program.

18. A machine readable storage device or storage disk as defined in claim 15 , wherein the first type of data includes a skip byte, the second type of data includes compressed audio content or compressed video content and the predetermined location is an auxiliary data field.

19. A machine readable storage device or storage disk as defined in claim 15 , wherein the compressed data bitstream is AC-3 compliant.

20. A machine readable storage device or storage disk as defined in claim 19 , wherein the instructions, when executed, cause the machine to re-compute cyclical redundancy check values for each AC-3 frame of the compressed data bitstream after inserting the audience measurement data in the predetermined location.