Management of presentation time in a digital media presentation system with variable rate presentation capability

• US 20050078113A1
• Filed: 08/17/2004
• Published: 04/14/2005
• Est. Priority Date: 12/11/2001
• Status: Active Grant

• Current Assignee: Virentem Ventures LLC
• Original Assignee: Enounce Incorporated
• Inventors: Bianchi, Edward J., Goldhor, Richard S.
• Granted Patent: US 7,683,903 B2
• Time in Patent Office: Days
• US Class Current: 345/472
• CPC Class Codes: G06F 16/41 Indexing; Data structures therefor; Storage structures
• CPC Class Codes: G06F 16/4393 Multimedia presentations, e.g. slide shows, multimedia albums
• CPC Class Codes: G06F 3/165 Management of the audio stream, e.g. setting of volume, audio stream path
• CPC Class Codes: G11B 27/005 Reproducing at a different information rate from the information rate of recording for television signals H04N5/783

Abstract

Techniques are provided for managing Presentation Time in a digital rendering system for presentation of temporally-ordered data when the digital rendering system includes a Variable Rate Presentation capability. In one embodiment, Presentation Time is converted to Data Time, and Data Time is reported instead of Presentation Time when only one time can be reported. In another embodiment, a predetermined one of Presentation Time and Data Time is returned in response to a request for a Current Time.

Claims

1. A method for rendering temporal sequence presentation data in a rendering system, the method comprising steps of:

(A) identifying a value of a presentation time parameter representing an amount of time elapsed during rendering of a portion of the temporal sequence presentation data;

(B) providing the value of the presentation time parameter to a first component of the rendering system;

(C) identifying a value of a data time parameter representing an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate; and

(D) providing the value of the data time parameter to a second component of the rendering system.

2. The method of claim 1, wherein the first component and the second component are the same component of the rendering system.

3. The method of claim 1, wherein the step (B) comprises a step of providing the presentation time parameter value in response to a request from the first component for a current time.

4. The method of claim 1, wherein the step (D) comprises a step of providing the data time parameter value in response to a request from the second component for a current time.

5. The method of claim 1, wherein the presentation time parameter value and the data time parameter value represent different times.

6. The method of claim 1, wherein the step (C) comprises steps of:

(C)(1) identifying a number of elements in the portion of the temporal sequence presentation data;

(C)(2) identifying a rendition period required to render one of the elements in the portion of the temporal sequence presentation data; and

(C)(3) multiplying the number of elements by the identified rendition period to identify the value of the data time parameter.

7. The method of claim 1, wherein the step (C) comprises steps of:

(C)(1) initializing the data time parameter value to zero;

(C)(2) for each element in the portion of the temporal sequence presentation data;

(a) identifying a default rendition period of the element;

(b) adding the default rendition period to the data time parameter value; and

(C)(3) providing the sum produced by steps (C)(1) and (C)(2) as the data time parameter value.

8. The method of claim 1, wherein the step (C) comprises steps of:

(C)(1) initializing the data time parameter value to zero;

(C)(2) for each element in the portion of the temporal sequence presentation data;

(a) identifying an actual rendition period of the element;

(b) identifying an actual presentation rate of the element;

(c) multiplying the actual rendition period of the element by the actual presentation rate of the element;

(d) adding the product of step (c) to the data time parameter value; and

(C)(3) providing the sum produced by steps (C)(1) and (C)(2) as the data time parameter value.

9. The method of claim 1, wherein the step (C) comprises a step of identifying, as the value of the data time parameter, a time integral of a presentation rate of the portion over the amount of time elapsed during rendering of the portion, wherein the presentation rate is equal to the ratio of a change in the value of the data time parameter over time to a change in the value of the presentation time parameter over time.

10. The method of claim 1, wherein the step (A) comprises steps of:

(A)(1) initializing the presentation time parameter value to zero;

(A)(2) for each element in the portion of the temporal sequence presentation data;

(a) identifying a default rendition period of the element;

(b) identifying an actual presentation rate of the element;

(c) dividing the default rendition period of the element by the actual presentation rate of the element;

(d) adding the result of step (c) to the presentation time parameter value; and

(A)(3) providing the sum produced by steps (A)(1) and (A)(2) as the presentation time parameter value.

11. The method of claim 1, wherein the step (B) comprises steps of:

(B) (1) receiving an explicit request for the value of the presentation time parameter; and

(B) (2) providing the value of the presentation time parameter in response to the request.

12. The method of claim 1, wherein the step (D) comprises steps of:

(D)(1) receiving an explicit request for the value of the data time parameter; and

(D)(2) providing the value of the data time parameter in response to the request.

13. A method for rendering temporal sequence presentation data in a rendering system, the method comprising steps of:

(A) receiving a request from a first component of the rendering system for a first current time;

(B) identifying a value of a presentation time parameter representing an amount of time elapsed during rendering of a portion of the temporal sequence presentation data;

(C) providing the value of the presentation time parameter to the first component in response to the request;

(D) receiving a request from a second component of the rendering system for a second current time;

(E) identifying a value of a data time parameter representing an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate; and

(F) providing the value of the data time parameter to the second component in response to the request;

wherein the presentation time parameter value and the data time parameter value represent different times.

14. A device for rendering temporal sequence presentation data in a rendering system, the device comprising:

first identification means for identifying a value of a presentation time parameter representing an amount of time elapsed during rendering of a portion of the temporal sequence presentation data;

first provision means for providing the value of the presentation time parameter to a first component of the rendering system;

second identification means for identifying a value of a data time parameter representing an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate; and

second provision means for providing the value of the data time parameter to a second component of the rendering system.

15. The device of claim 14, wherein the first component and the second component are the same component of the rendering system.

16. The device of claim 14, wherein the second identification means comprises:

third identification means for identifying a number of elements in the portion of the temporal sequence presentation data;

fourth identification means for identifying a rendition period required to render one of the elements in the portion of the temporal sequence presentation data; and

multiplication means for multiplying the number of elements by the identified rendition period to identify the value of the data time parameter.

17. The device of claim 14, wherein the second identification means comprises:

initialization means for initializing the data time parameter value to zero;

iteration means for each element in the portion of the temporal sequence presentation data, the iteration means comprising;

third identification means for identifying a default rendition period of the element;

addition means for adding the default rendition period to the data time parameter value; and

third provision means for providing the sum produced by the initialization means and the iteration means as the data time parameter value.

18. The device of claim 14, wherein the second identification means comprises:

initialization means for initializing the data time parameter value to zero;

iteration means for each element in the portion of the temporal sequence presentation data, the iteration means comprising;

third identification means for identifying an actual rendition period of the element;

fourth identification means for identifying an actual presentation rate of the element;

multiplication means for multiplying the actual rendition period of the element by the actual presentation rate of the element;

addition means for adding the product produced by the multiplication means to the data time parameter value; and

third provision means for providing the sum produced by the initialization means and the iteration means as the data time parameter value.

19. The device of claim 14, wherein the second identification means comprises means for identifying, as the value of the data time parameter, a time integral of a presentation rate of the portion over the amount of time elapsed during rendering of the portion, wherein the presentation rate is equal to the ratio of a change in the value of the data time parameter over time to a change in the value of the presentation time parameter over time.

20. The device of claim 14, wherein the first identification means comprises:

initialization means for initializing the presentation time parameter value to zero;

iteration means for each element in the portion of the temporal sequence presentation data, the iteration means comprising;

third identification means for identifying a default rendition period of the element;

fourth identification means for identifying an actual presentation rate of the element;

division means for dividing the default rendition period of the element by the actual presentation rate of the element;

addition means for adding the quotient produced by the division means to the presentation time parameter value; and

third provision means for providing the sum produced by the initialization means and the iteration means as the presentation time parameter value.

21. The device of claim 14, wherein the first provision means comprises:

reception means for receiving an explicit request for the value of the presentation time parameter; and

third provision means for providing the value of the presentation time parameter in response to the request.

22. The device of claim 14, wherein the second provision means comprises:

reception means for receiving an explicit-request for the value of the data time parameter; and

third provision means for providing the value of the data time parameter in response to the request.

23. A device for rendering temporal sequence presentation data in a rendering system, the device comprising:

means for receiving a request from a first component of the rendering system for a first current time;

means for identifying a value of a presentation time parameter representing an amount of time elapsed during rendering of a portion of the temporal sequence presentation data;

means for providing the value of the presentation time parameter to the first component in response to the request;

means for receiving a request from a second component of the rendering system for a second current time;

means for identifying a value of a data time parameter representing an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate; and

means for providing the value of the data time parameter to the second component in response to the request;

wherein the presentation time parameter value and the data time parameter value represent different times.

24. A method for use in a rendering system for rendering temporal sequence presentation data, the method comprising steps of:

(A) initializing a presentation time parameter value to zero, the presentation time parameter representing an amount of time elapsed during rendering of a portion of the temporal sequence presentation data;

(B) for each element in the portion of the temporal sequence presentation data;

(1) identifying a default rendition period of the element;

(2) identifying an actual presentation rate of the element;

(3) dividing the default rendition period of the element by the actual presentation rate of the element;

(4) adding the quotient of step (3) to the presentation time parameter value; and

(C) identifying the sum produced by steps (A) and (B) as the presentation time parameter value.

25. A device for use in a rendering system for rendering temporal sequence presentation data, the device comprising:

initialization means for initializing a presentation time parameter value to zero, the presentation time parameter representing an amount of time elapsed during rendering of a portion of the temporal sequence presentation data;

iteration means for each element in the portion of the temporal sequence presentation data, the iteration means comprising;

first identification means for identifying a default rendition period of the element;

second identification means for identifying an actual presentation rate of the element;

division means for dividing the default rendition period of the element by the actual presentation rate of the element;

summing means for adding the quotient produced by the division means to the presentation time parameter value; and

third identification means for identifying the sum produced by the initialization means and the iteration means as the presentation time parameter value.

26. A method for use in a rendering system for rendering temporal sequence presentation data, the method comprising steps of:

(A) receiving an explicit request for a value of a presentation time parameter representing an amount of time elapsed during rendering of a portion of the temporal sequence presentation data, wherein the amount of time differs from an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate; and

(B) providing the value of the presentation time parameter in response to the request.

27. A device for use in a rendering system for rendering temporal sequence presentation data, the device comprising:

means for receiving an explicit request for a value of a presentation time parameter representing an amount of time elapsed during rendering of a portion of the temporal sequence presentation data, wherein the amount of time differs from an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate; and

means for providing the value of the presentation time parameter in response to the request.

28. A method for use in a rendering system for rendering temporal sequence presentation data, the method comprising steps of:

(A) receiving an explicit request for the value of a data time parameter representing an amount of time required to render a portion of the temporal sequence presentation data at a default presentation rate, wherein the amount of time differs from an amount of time elapsed during rendering of the portion of the temporal sequence presentation data; and

(B) providing the value of the data time parameter in response to the request.

29. A device for use in a rendering system for rendering temporal sequence presentation data, the device comprising:

means for receiving an explicit request for the value of a data time parameter representing an amount of time required to render a portion of the temporal sequence presentation data at a default presentation rate, wherein the amount of time differs from an amount of time elapsed during rendering of the portion of the temporal sequence presentation data; and

means for providing the value of the data time parameter in response to the request.

30. A method for enhancing a rendering system which renders temporal sequence presentation data, the rendering system not including distinct current presentation time and current data time parameters, the method comprising steps of:

(A) adding to the rendering system a monitoring module for monitoring values of a current presentation rate parameter that may vary over time, the current presentation rate parameter representing a current rate at which the portion of the temporal sequence presentation data is being rendered; and

(B) adding to the rendering system a data time module to identify, based on the values of the current presentation rate parameter, a current data time parameter value representing an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate.

31. The method of claim 30, further comprising a step of:

(C) adding to the rendering system a presentation rate modification module to render a portion of the temporal sequence presentation data at any of a plurality of presentation rates.

32. The method of claim 30, further comprising a step of:

(C) adding to the rendering system a current time module for returning the value of a predetermined one of the presentation time parameter and the data time parameter in response to a request for a current time.

33. The method of claim 30, wherein the presentation time parameter has a value that differs from the data time parameter value.

34. A method for enhancing a rendering system which renders temporal sequence presentation data, the rendering system not including distinct current presentation time and current data time parameters, the method comprising steps of:

(A) adding to the rendering system a monitoring module for monitoring values of a current presentation rate parameter that may vary over time, the current presentation rate parameter representing a current rate at which the portion of the temporal sequence presentation data is being rendered;

(B) adding to the rendering system a data time module to identify, based on the values of the current presentation rate parameter, a current data time parameter value representing an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate;

(C) adding to the rendering system a presentation rate modification module to render a portion of the temporal sequence presentation data at any of a plurality of presentation rates; and

(D) adding to the rendering system a current time module for returning the value of a predetermined one of the presentation time parameter and the data time parameter in response to a request for a current time;

wherein the presentation time parameter has a value that differs from the data time parameter value.

35. A system comprising:

a rendering system which renders temporal sequence presentation data, the rendering system not including distinct current presentation time and current data time parameters;

a monitoring module for monitoring values of a current presentation rate parameter that may vary over time, the current presentation rate parameter representing a current rate at which the portion of the temporal sequence presentation data is being rendered; and

a data time module to identify, based on the values of the current presentation rate parameter, a current data time parameter value representing an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate.

36. The system of claim 35, further comprising:

a presentation rate modification module to render a portion of the temporal sequence presentation data at any of a plurality of presentation rates.

37. The system of claim 35, further comprising:

a current time module for returning the value of a predetermined one of the presentation time parameter and the data time parameter in response to a request for a current time.

38. The system of claim 35, wherein the presentation time parameter has a value that differs from the data time parameter value.

39. A system comprising:

a rendering system which renders temporal sequence presentation data, the rendering system not including distinct current presentation time and current data time parameters;

a monitoring module for monitoring values of a current presentation rate parameter that may vary over time, the current presentation rate parameter representing a current rate at which the portion of the temporal sequence presentation data is being rendered;

a data time module to identify, based on the values of the current presentation rate parameter, a current data time parameter value representing an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate;

a presentation rate modification module to render a portion of the temporal sequence presentation data at any of a plurality of presentation rates; and

a current time module for returning the value of a predetermined one of the presentation time parameter and the data time parameter in response to a request for a current time;

wherein the presentation time parameter has a value that differs from the data time parameter value.

40. A method for enhancing a rendering system which renders temporal sequence presentation data, the rendering system not including distinct current presentation time and current data time parameters, the method comprising steps of:

(A) adding to the rendering system a monitoring module for monitoring values of a current presentation rate parameter that may vary over time, the current presentation rate parameter representing a current rate at which the portion of the temporal sequence presentation data is being rendered; and

(B) adding to the rendering system a presentation time module to identify, based on the values of the current presentation rate parameter, a current presentation time parameter value representing an amount of time required to render the portion of the temporal sequence presentation data at the current rate.

41. The method of claim 40, further comprising a step of:

(C) adding to the rendering system a presentation rate modification module to render a portion of the temporal sequence presentation data at any of a plurality of presentation rates.

42. The method of claim 40, further comprising a step of:

(C) adding to the rendering system a current time module for returning the value of a predetermined one of the presentation time parameter and the data time parameter in response to a request for a current time.

43. The method of claim 40, wherein the presentation time parameter has a value that differs from the data time parameter value.

44. A method for enhancing a rendering system which renders temporal sequence presentation data, the rendering system not including distinct current presentation time and current data time parameters, the method comprising steps of:

(A) adding to the rendering system a monitoring module for monitoring values of a current presentation rate parameter that may vary over time, the current presentation rate parameter representing a current rate at which the portion of the temporal sequence presentation data is being rendered;

(B) adding to the rendering system a presentation time module to identify, based on the values of the current presentation rate parameter, a current presentation time parameter value representing an amount of time required to render the portion of the temporal sequence presentation data at the current rate;

(C) adding to the rendering system a presentation rate modification module to render a portion of the temporal sequence presentation data at any of a plurality of presentation rates; and

(D) adding to the rendering system a current time module for returning the value of a predetermined one of the presentation time parameter and the data time parameter in response to a request for a current time;

wherein the presentation time parameter has a value that differs from the data time parameter value.

45. A system comprising:

a rendering system which renders temporal sequence presentation data, the rendering system not including distinct current presentation time and current data time parameters;

a monitoring module for monitoring values of a current presentation rate parameter that may vary over time, the current presentation rate parameter representing a current rate at which the portion of the temporal sequence presentation data is being rendered; and

a presentation time module to identify, based on the values of the current presentation rate parameter, a current presentation time parameter value representing an amount of time required to render the portion of the temporal sequence presentation data at the current rate.

46. The system of claim 45, further comprising:

a presentation rate modification module to render a portion of the temporal sequence presentation data at any of a plurality of presentation rates.

47. The system of claim 45, further comprising:

a current time module for returning the value of a predetermined one of the presentation time parameter and the data time parameter in response to a request for a current time.

48. The system of claim 45, wherein the presentation time parameter has a value that differs from the data time parameter value.

49. A system for enhancing a rendering system which renders temporal sequence presentation data, the rendering system not including distinct current presentation time and current data time parameters, the system comprising:

a monitoring module for monitoring values of a current presentation rate parameter that may vary over time, the current presentation rate parameter representing a current rate at which the portion of the temporal sequence presentation data is being rendered;

a presentation time module to identify, based on the values of the current presentation rate parameter, a current presentation time parameter value representing an amount of time required to render the portion of the temporal sequence presentation data at the current rate;

a presentation rate modification module to render a portion of the temporal sequence presentation data at any of a plurality of presentation rates; and

a current time module for returning the value of a predetermined one of the presentation time parameter and the data time parameter in response to a request for a current time;

wherein the presentation time parameter has a value that differs from the data time parameter value.

50. A method for use in conjunction with a rendering system which renders temporal sequence presentation data, the method comprising steps of:

(A) receiving a request for a current time of the temporal sequence presentation data after a portion of the temporal sequence presentation data has been rendered by the rendering system;

(B) in response to the request, performing steps of;

(1) identifying a data time parameter value representing an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate; and

(2) providing the data time parameter value in response to the request.

51. The method of claim 50, wherein the step (B) comprises steps of:

(B)(1)(a) identifying a number of elements in the portion of the temporal sequence presentation data;

(B)(1)(b) identifying a rendition period required to render one of the elements in the portion of the temporal sequence presentation data; and

(B)(1)(c) multiplying the number of elements by the identified rendition period to identify the value of the data time parameter.

52. The method of claim 50, wherein the step (B) comprises steps of:

(B)(1) (a) initializing the data time parameter value to zero;

(B)(1) (b) for each element in the portion of the temporal sequence presentation data;

(i) identifying a default rendition period of the element;

(ii) adding the default rendition period to the data time parameter value; and

(B) (2) providing the sum produced by steps (B)(1)(a) and (B)(1)(b) as the data time parameter value.

53. The method of claim 50, wherein the step (B) comprises steps of:

(B)(1)(a) initializing the data time parameter value to zero;

(B)(1)(b) for each element in the portion of the temporal sequence presentation data;

(i) identifying an actual rendition period of the element;

(ii) identifying an actual presentation rate of the element;

(iii) multiplying the actual rendition period of the element by the actual presentation rate of the element;

(iv) adding the product of step (c) to the data time parameter value; and

(B)(2) providing the sum produced by steps (B)(1)(a) and (B)(1)(b) as the data time parameter value.

54. The method of claim 50, wherein the step (B) comprises a step of identifying, as the value of the data time parameter, a time integral of a presentation rate of the portion over the amount of time elapsed during rendering of the portion, wherein the presentation rate is equal to the ratio of a change in the value of the data time parameter over time to a change in the value of the presentation time parameter over time.

55. A device for use in conjunction with a rendering system which renders temporal sequence presentation data, the device comprising:

means for receiving a request for a current time of the temporal sequence presentation data after a portion of the temporal sequence presentation data has been rendered by the rendering system;

response means activated by receipt of the request, the response means comprising;

means for identifying a data time parameter value representing an amount of time required to render the portion of the temporal sequence presentation data at a default presentation rate; and

means for providing the data time parameter value in response to the request.

56. A method for use in conjunction with a rendering system which renders temporal sequence presentation data, the method comprising steps of:

(A) receiving a request for a current time of the temporal sequence presentation data after a portion of the temporal sequence presentation data has been rendered by the rendering system;

(B) determining, based on a property of the request, whether to return a value of a data time parameter or a value of a presentation time parameter; and

(C) returning, in response to the request, the value determined in step (B).

57. The method of claim 56, wherein the property comprises an property of an executing computer program which submitted the request.

58. The method of claim 56, wherein the property comprises a property of a computer platform on which the method is executing.

59. The method of claim 56, wherein the property comprises a value accessible to the method during step (B).

60. A device for use in conjunction with a rendering system which renders temporal sequence presentation data, the device comprising:

means for receiving a request for a current time of the temporal sequence presentation data after a portion of the temporal sequence presentation data has been rendered by the rendering system;

means for determining, based on a property of the request, whether to return a value of a data time parameter or a value of a presentation time parameter; and

means for returning, in response to the request, the value determined by the means for determining.

61. A method for use in conjunction with a rendering system which renders temporal sequence presentation data, the method comprising steps of:

(A) receiving a request for a current time of the temporal sequence presentation data after a portion of the temporal sequence presentation data has been rendered by the rendering system;

(B) identifying an initial current time of the temporal sequence presentation data;

(C) identifying at least one presentation rate associated with the temporal sequence presentation data;

(D) modifying the initial current time based on the identified at least one presentation rate to produce a modified current time; and

(E) providing the modified current time in response to the request.

62. The method of claim 61, wherein step (B) comprises a step of identifying a presentation time of the temporal sequence presentation data.

63. The method of claim 61, wherein step (B) comprises a step of identifying a data time of the temporal sequence presentation data.

64. The method of claim 61, wherein step (C) comprises a step of identifying a current presentation rate of the temporal sequence presentation data.

65. The method of claim 61, wherein step (C) comprises a step of identifying a presentation rate of the temporal sequence presentation data during rendering of the portion of the temporal sequence presentation data by the rendering system.

66. The method of claim 61, wherein step (D) comprises a step of adding to the initial current time a value that is proportional to the identified presentation rate.

67. The method of claim 61, wherein step (D) comprises a step of subtracting from the initial current time a value that is proportional to the identified presentation rate.

68. The method of claim 61, wherein the step (A) comprises a step of receiving the request from a requesting component, and wherein the step (D) comprises steps of:

(D)(1) identifying a first offset expected to be added by the requesting component to the modified current time;

(D)(2) identifying a second offset based on the identified at least one presentation rate;

(D)(3) adding the second offset to the initial current time to produce an intermediate current time; and

(D)(4) subtracting the first offset from the intermediate current time to produce the modified current time.

69. A device for use in conjunction with a rendering system which renders temporal sequence presentation data, the device comprising:

means for receiving a request for a current time of the temporal sequence presentation data after a portion of the temporal sequence presentation data has been rendered by the rendering system;

means for identifying an initial current time of the temporal sequence presentation data;

means for identifying at least one presentation rate associated with the temporal sequence presentation data;

means for modifying the initial current time based on the identified at least one presentation rate to produce a modified current time; and

means for providing the modified current time in response to the request.

70. A method for use in conjunction with a rendering system which renders temporal sequence presentation data including a plurality of data samples, the method comprising steps of:

(A) grouping the plurality of data samples into a plurality of buffers;

(B) associating with each of the plurality of buffers a corresponding presentation rate;

(C) associating with each of the plurality of buffers a corresponding initial data time;

(D) associating with each of the plurality of buffers a corresponding initial presentation time;

(E) associating with each of the plurality of buffers a default rendition period; and

(F) associating with each of the plurality of buffers an actual rendition period.

71. The method of claim 70, wherein the plurality of buffers is logically arranged in an ordered sequence, and wherein the step (C) comprises steps of, for each of the plurality of buffers:

(C) (1) identifying the initial data time associated with the previous buffer in the ordered sequence;

(C)(2) identifying the default rendition period of the previous-buffer in the ordered sequence; and

(C)(3) identifying the initial data time of the buffer as the sum of the initial data time identified in step (C)(1) and the default rendition period identified in step (C)(2).

72. The method of claim 70, wherein the plurality of buffers is logically arranged in an ordered sequence, and wherein the step (D) comprises steps of, for each of the plurality of buffers:

(D)(1) identifying the initial presentation time associated with the previous buffer in the ordered sequence;

(D)(2) identifying the actual rendition period of the previous buffer in the ordered sequence; and

(D)(3) identifying the initial presentation time of the buffer as the sum of the initial presentation time identified in step (D)(1) and the actual rendition period identified in step (D)(2).

73. The method of claim 70, wherein the plurality of buffers is logically arranged in an ordered sequence, and wherein the step (F) comprises steps of, for each of the plurality of buffers:

(F)(1) identifying the number of samples in the buffer;

(F)(2) identifying the default rendition period of a sample in the buffer; and

(F)(3) identifying the actual rendition period of the buffer as the product of the identified number of samples times the identified default rendition period of a sample in the buffer.

74. A device for use in conjunction with a rendering system which renders temporal sequence presentation data including a plurality of data samples, the device comprising:

grouping means for grouping the plurality of data samples into a plurality of buffers;

first association means for associating with each of the plurality of buffers a corresponding presentation rate;

second association means for associating with each of the plurality of buffers a corresponding initial data time;

third association means for associating with each of the plurality of buffers a corresponding initial presentation time;

fourth association means for associating with each of the plurality of buffers a default rendition period; and

fifth association means for associating with each of the plurality of buffers an actual rendition period.