System and method for conversion of text embedded in a video stream

• US 20030035063A1
• Filed: 08/20/2001
• Published: 02/20/2003
• Est. Priority Date: 08/20/2001
• Status: Active Grant

• Current Assignee: ATI Technologies Incorporated (Advanced Micro Devices, Inc.)
• Original Assignee: ATI Technologies Incorporated (Advanced Micro Devices, Inc.)
• Inventors: Orr, Stephen J.
• Granted Patent: US 6,952,236 B2
• Time in Patent Office: Days
• US Class Current: 348/465
• CPC Class Codes: H04N 7/0882 for the transmission of character code signals, e.g. for teletext circuits for the digital non-picture data signal H04N7/035
• CPC Class Codes: H04N 7/0885 for the transmission of subtitles

Abstract

A system and method for converting text data having a Teletext format to text data having an Electronics Industries Associations-608 (EIA-608) format are illustrated herein. A video stream with embedded text data having a Teletext format is received by a dual mode text processing system. The dual mode text processing system, in one embodiment, extracts the text data and filters the text data to identify a desired portion using an identifier, such as a page identifier or number. The desired portion (or a copy thereof), once identified, is sent to a line break parser. The line break parser, in one embodiment, eliminates some or all of any unnecessary or unintended line breaks, as well as some or all of any extra space characters, to generate a character stream. The character stream, in one embodiment, is then converted into a EIA-608 format by a line convertor, wherein the character stream is parsed into one or more subtitle lines with a maximum character length. An end-of-line break, in one embodiment, is added to the end of each subtitle line. The output of the line convertor, in one embodiment, is buffered by a rate modulator which outputs the buffered text data at a specified rate to minimize the character transmission rate disparity between the Teletext and EIA-608 specifications. The output of the rate modulator can then be encoded into an EIA-608 format by an EIA-608 encoder. The EIA-608 encoded data can then be decoded by a closed captioning decoder and displayed as Closed Captioning text subtitles, stored in file storage, processed by a software or hardware application, and the like.

Claims

1. A method comprising the steps of:

identifying a first text portion having a first format, wherein the text portion is embedded in a video stream; and

converting the first text portion having the first format to a second text portion having a second format different from the first format.

2. The method of claim 1, wherein:

the first format includes a Teletext format; and

the second format includes a Closed Captioning format.

3. The method of claim 2, wherein the first text portion is part of a subtitle page.

4. The method of claim 1, wherein:

the first format includes a Closed Captioning format; and

the second format includes a Teletext format.

5. The method of claim 1, wherein the step of identifying includes the steps of:

filtering the first text portion to identify a desired portion; and

copying a set of data associated with the desired portion when the desired portion is identified.

6. The method of claim 5, wherein the desired portion is identified based on a page identifier.

7. The method of claim 6, wherein the page identifier identifies a subtitle page.

8. The method of claim 6, wherein the page identifier is determined based on a transmission source of the video stream.

9. The method of claim 6, wherein the page identifier is determined based on user input.

10. The method of claim 1, wherein the step of converting includes the step of reformatting the first text portion from a first character display format to a second character display format to generate a converted text portion.

11. The method of claim 10, wherein:

the first character display format includes a maximum N characters-per-display line format; and

the second character display format includes a maximum M characters-per-display line format, where N and M are different integer numbers.

12. The method of claim 11, wherein N is 40 and M is 32.

13. The method of claim 10, wherein the step of reformatting includes the step of eliminating an unintended line break while keeping a deliberate line break.

14. The method of claim 1, further including the step of providing the second text portion to an application, wherein the application is to utilize the second text portion.

15. The method of claim 14, further including the steps of:

identifying a third text portion having the first text format, wherein the third text portion is embedded in the video stream;

comparing the third text portion to the first text portion to detect a substantial match; and

excluding the third text portion from being provided to the application when a substantial match is detected.

16. The method of claim 14, wherein the application is to analyze the second text portion for at least one keyword.

17. The method of claim 14, wherein the application is to generate a transcript based on the second text portion.

18. The method of claim 14, wherein the application is to display the second text portion as Closed Captioning text.

19. The method of claim 14, wherein the application is to buffer the second text portion to provide a Closed Captioning history navigable by a user.

20. The method of claim 14, wherein the second text portion is provided to the application at a specified rate.

21. The method of claim 20, wherein the specified rate is determined experimentally.

22. The method of claim 20, wherein the specified rate is determined based on a size of a buffer used to buffer the second text portion before the second text portion is provided to the application.

23. A method comprising the steps of:

filtering a set of Teletext data to identify a first set of text; and

converting the first set of text from a first character display format to a second set of text having a second character display format different from the first character display format.

24. The method of claim 23, wherein the second character display format is based on a Closed Captioning format.

25. The method of claim 23, wherein the first set of text is identified based on a page identifier.

26. The method of claim 25, wherein the page identifier identifies a subtitle page.

27. The method of claim 25, wherein the page identifier is determined based on a transmission source of the video stream.

28. The method of claim 25, wherein the page identifier is determined based on user input.

29. The method of claim 25, wherein the page identifier includes a subtitle identifier flag in the set of Teletext data.

30. The method of claim 23, wherein:

the first character display format includes a maximum N characters-per-display line format; and

the second character display format includes a maximum M characters-per-display line format, where N and M are different integer numbers.

31. The method of claim 30, wherein N is 40 and M is 32.

32. The method of claim 23, wherein the step of converting includes eliminating an inadvertent line break while keeping a deliberate line break.

33. The method of claim 23, wherein the first set of text is part of a subtitle page of the Teletext data.

34. The method of claim 23, wherein the step of filtering includes the step of generating a copy of the first set of text used for performing the step of converting.

35. The method of claim 23, further including the step of providing the second embedded text portion to an application, wherein the application is to utilize the second embedded text portion.

36. The method of claim 35, further including the step of:

filtering the set of Teletext data to identify a third set of text; and

comparing the third set of text to the first set of text to detect a substantial match; and

excluding the third set of text from being provided to the application when a substantial match is detected.

37. The method of claim 35, wherein the second set of text is provided to the application at a specified rate.

38. The method of claim 37, wherein the specified rate is determined experimentally.

39. The method of claim 37, wherein the specified rate is determined dynamically based on a size of a buffer used to buffer the second text portion before the second text portion is provided to the application.

40. The method of claim 37, wherein the application is to analyze the second text portion for at least one keyword.

41. The method of claim 37, wherein the application is to generate a transcript based on the second text portion.

42. The method of claim 37, wherein the application is to display the second text portion as Closed Captioning text.

43. The method of claim 37, wherein the application is to buffer the second text portion to provide a Closed Captioning history navigable by a user.

44. A system comprising:

a filter to identify a first portion of a text portion embedded in a video stream, said text portion having a first character display format;

a line parser to parse one or more characters from said first portion to generate a character stream; and

a line converter to convert said character stream to a second portion having a second character display format.

45. The system of claim 44, wherein the first character display format includes a Teletext display format and the second character display format includes a Closed Captioning format.

46. The system of claim 44, wherein the first character display format includes a Closed Captioning display format and the second character display format includes a Teletext format.

47. The system of claim 44, wherein the first character display format includes a maximum N characters-per-display line format and the second character display format includes a maximum M characters-per-display line format, where N and M are different integer numbers.

48. The system of claim 47, wherein N is 40 and M is 32.

49. The system of claim 47, wherein N is 32 and M is 40.

50. The system of claim 44, wherein said text portion includes a subtitle identifier flag associated with said first portion, and wherein said subtitle identifier flag is used by said filter to identify said first portion.

51. The system of claim 44, wherein said first portion is identified based on a page identifier.

52. The system of claim 51, wherein said page identifier includes a subtitle page.

53. The system of claim 51, wherein the page identifier is determined based on a transmission source of said video stream.

54. The system of claim 51, wherein said page identifier is determined based on user input.

55. The system of claim 44, further including a copy module to generate a copy of the first portion and wherein said copy of the first portion is used by said line parser.

56. The system of claim 44, further including an application to utilize said second portion.

57. The system of claim 56, further including a rate modulator to output said second portion at a first output rate to said application.

58. The system of claim 57, wherein said first output rate is determined experimentally.

59. The system of claim 57, wherein said first output rate is determined dynamically.

60. The system of claim 59, wherein said rate modulator includes a buffer to buffer said second portion, and where said first output rate is determined based on an extent to which said buffer is populated.

61. The system of claim 57, wherein said rate modulator further is to:

compare said second portion with a previous portion of said text portion converted by said line converter to detect a substantial match; and

exclude said second portion from being provided to said application when a substantial match is detected.

62. The system of claim 56, wherein said application is to analyze said second text portion for at least one keyword.

63. The system of claim 56, wherein said application is to generate a transcript based on said second text portion.

64. The system of claim 56, wherein said application is to display said second text portion as Closed Captioning text.

65. The system of claim 56, wherein said application is to buffer said second text portion to provide a Closed Captioning history navigable by a user.

66. A computer readable medium, said computer readable medium including instructions to manipulate a processor to:

identify a first text portion having a first format, wherein the text portion is embedded in a video stream; and

convert the first text portion having the first format to a second text portion having a second format different from the first format.

67. The computer readable medium of claim 66, wherein:

the first format includes a Teletext format; and

the second format includes a Closed Captioning format.

68. The computer readable medium of claim 67, wherein the first text portion is part of a subtitle page.

69. The computer readable medium of claim 66, wherein:

the first format includes a Closed Captioning format; and

the second format includes a Teletext format.

70. The computer readable medium of claim 66, wherein said instructions to manipulate said processor include instructions to manipulate said processor to:

filter the first text portion to identify a desired portion; and

copy a set of data associated with the desired portion when the desired portion is identified.

71. The computer readable medium of claim 70, wherein the desired portion is identified based on a page identifier.

72. The computer readable medium of claim 71, wherein the page identifier includes a subtitle identifier flag associated with the first text portion in the video stream.

73. The computer readable medium of claim 71, wherein the page identifier identifies a subtitle page.

74. The computer readable medium of claim 71, wherein the page identifier is determined based on a transmission source of the video stream.

75. The computer readable medium of claim 71, wherein the page identifier is determined based on user input.

76. The computer readable medium of claim 66, wherein said instructions to manipulate said processor to convert include instructions to manipulate said processor to reformat the first text portion from a first character display format to a second character display format to generate a converted text portion.

77. The computer readable medium of claim 76, wherein:

the first character display format includes a maximum N characters-per-display line format; and

the second character display format includes a maximum M characters-per-display line format, where N and M are different integer numbers.

78. The computer readable medium of claim 77, wherein N is 40 and M is 32.

79. The computer readable medium of claim 76, wherein said instructions to manipulate said processor to reformat include instructions to manipulate said processor to eliminate an unintended line break while keeping a deliberate line break.

80. The computer readable medium of claim 66, further including instructions to manipulate said processor to provide the second text portion to an application, wherein the application is to utilize the second text portion.

81. The computer readable medium of claim 80, further including instructions to manipulate said processor to:

identify a third text portion having the first text format, wherein the third text portion is embedded in the video stream;

compare the third text portion to the first text portion to detect a substantial match; and

exclude the third text portion from being provided to the application when a substantial match is detected.

82. The computer readable medium of claim 80, wherein the application is to analyze the second text portion for at least one keyword.

83. The computer readable medium of claim 80, wherein the application is to generate a transcript based on the second text portion.

84. The computer readable medium of claim 80, wherein the application is to display the second text portion as Closed Captioning text.

85. The computer readable medium of claim 80, wherein the application is to buffer the second text portion to provide a Closed Captioning history navigable by a user.

86. The computer readable medium of claim 80, wherein the second text portion is provided to the application at a specified rate.

87. The computer readable medium of claim 83, wherein the specified rate is determined experimentally.

88. The computer readable medium of claim 83, wherein the specified rate is determined based on a size of a buffer used to buffer the second text portion before the second text portion is provided to the application.