Methods and systems for determining audio loudness levels in programming

• US 8,379,880 B2
• Filed: 06/02/2008
• Issued: 02/19/2013
• Est. Priority Date: 08/25/2003
• Status: Active Grant

• Current Assignee: Time Warner Cable Enterprises LLC (Charter Communications Incorporated)
• Original Assignee: Time Warner Cable Inc. (Charter Communications Incorporated)
• Inventors: Riedl, Steven E.
• Primary Examiner(s): Paul, Disler
• Application Number:
  US12/131,649
• Publication Number:
  US 20090046873A1
• Time in Patent Office: 1,723 Days
• Field of Search: 381104-109, 704/500, 704/224, 704/234, 704/200.1, 704503-504, 700/94
• US Class Current: 381/107
• CPC Class Codes: H03G 3/001 Digital control of analog signals
• CPC Class Codes: H03G 3/20 Automatic control H03G3/005 takes precedence; combined with volume compression or expansion H03G7/00
• CPC Class Codes: H03G 7/007 of digital or coded signals
• CPC Class Codes: H03G 9/005 of digital or coded signals
• CPC Class Codes: H04N 21/2335 involving reformatting operations of audio signals, e.g. by converting from one coding standard to another details of audio signal transcoding G10L19/173

Abstract

An example of a method of correcting an audio level of a stored program asset comprises retrieving a stored program asset having audio encoded at a first loudness setting. Dialog of the audio of the asset is identified, a loudness of the dialog is determined and the determined loudness is compared to the first loudness setting. The asset is re-encoded at a second loudness setting corresponding to the determined loudness, if the first loudness setting and the second loudness are different by more than a predetermined amount. The determined loudness is preferably a DIALNORM of the dialog. The asset may be stored with the re-encoded loudness setting. The method may be applied to programs as they are being received from a source, as well. Aspects of the method may also be applied to programs to be provided by a source. Systems are also disclosed.

Claims

1. A method of correcting an audio level of a stored program asset, comprising:

retrieving a stored program asset, the asset having audio encoded at a DIALNORM setting;

identifying dialog of the audio of the asset;

determining a DIALNORM of the dialog;

comparing the determined DIALNORM of the dialog to the DIALNORM setting; and

re-encoding the asset at a loudness setting corresponding to the determined DIALNORM of the dialog, if the DIALNORM setting and the determined DIALNORM of the dialog are different by more than a predetermined amount.

2. The method of claim 1, wherein the identifying of the dialog comprises identifying by:

dividing the audio into time intervals;

determining a loudness of each time interval; and

identifying time intervals with intermediate loudnesses.

3. The method of claim 2, wherein the determining of the loudness of each time interval is based on psycho-acoustic criteria.

4. The method of claim 3, wherein the determining of the loudness of each time interval is based on Leq (A).

5. The method of claim 2, further comprising the additional step of:

determining a loudness of the time intervals having an intermediate loudness.

6. The method of claim 5, wherein the determining of the loudness of the time intervals having intermediate loudnesses comprises computing a function of the loudnesses of the time intervals having intermediate loudness.

7. The method of claim 6, wherein:

the function is one of an average, a mean and a median of the loudnesses of the time intervals having intermediate loudness.

8. The method of claim 5, wherein the determining of the loudness of the time intervals having intermediate loudnesses comprises:

determining a DIALNORM of the time intervals having intermediate loudnesses.

9. The method of claim 1, further comprising the additional step of:

correcting compression of the audio of the program.

10. The method of claim 1, further comprising the additional steps of, prior to retrieving the stored program asset:

receiving a program from a source; and

storing the program in memory as an asset for later transmission.

11. The method of claim 1, further comprising the additional step of:

demultiplexing the audio from the program asset, prior to identifying the dialog.

12. The method of claim 1, further comprising the additional step of:

decompressing the audio, prior to identifying the dialog.

13. The method of claim 12 wherein the decompressing of the audio comprises converting the audio to a pulse coded modulation format.

14. The method of claim 1, further comprising the additional step of:

performing automatic gain control on the audio, prior to identifying the dialog.

15. The method of claim 1, further comprising the additional step of:

filtering the audio, prior to identifying the dialog.

16. The method of claim 1, wherein the identifying of the dialog comprises identifying the dialog by filtering the audio.

17. The method of claim 16, wherein the filtering of the audio comprises filtering the audio outside of a range of from about 100 Hertz to about 1,000 Hertz.

18. The method of claim 1, further comprising the additional steps of:

retrieving a second stored program asset, the second asset comprising audio encoded at a second DIALNORM setting;

identifying dialog of the second asset;

determining a second DIALNORM of the dialog of the second asset;

comparing the second DIALNORM of the dialog to the second DIALNORM setting; and

re-encoding the asset at the second DIALNORM of the dialog, if the DIALNORM setting and the second DIALNORM of the dialog are different by more than a predetermined amount.

19. The method of claim 1, wherein the asset comprises one of a program, a chapter of a program, and an advertisement.

20. The method of claim 1, further comprising the additional step of:

storing the asset with the re-encoded loudness setting.

21. The method of claim 1, wherein:

said step of retrieving said stored program asset comprises;

a staging processor portion of an acquisition and staging processor in a head end of a broadband communications system retrieving said asset from a memory of an asset manager in said head end; and

said staging processor storing said asset in a memory of said acquisition and staging processor;

said DIALNORM setting is established by a source of said asset, external to said head end; and

said identifying, determining, and comparing steps are performed by said staging processor portion; and

said re-encoding step is performed by an encoder portion of said staging processor portion.

22. The method of claim 21, wherein said staging processor portion performs the additional step of determining said DIALNORM setting by checking a DIALNORM in program specific information of said asset.

23. The method of claim 1, wherein said retrieving, identifying, determining, comparing, and re-encoding steps are carried out by a processor in a set-top terminal of a broadband communications system.

24. The method of claim 23, wherein said asset comprises advertising stored locally to said set-top terminal.

25. A method of correcting an audio level of a stored program asset, comprising:

retrieving a stored program asset, the asset comprising audio having an encoded DIALNORM setting;

demultiplexing the audio from the retrieved asset;

decompressing the audio;

identifying dialog of the audio;

determining a DIALNORM of the dialog;

comparing the determined DIALNORM to the encoded DIALNORM setting;

re-encoding the asset at the determined DIALNORM if the encoded DIALNORM and the determined DIALNORM are different by more than a predetermined amount; and

storing the asset with the re-encoded DIALNORM.

26. The method of claim 25, wherein the identifying of the dialog comprises identifying the dialog by:

dividing the audio into time intervals;

determining a loudness of each time interval; and

identifying time intervals with intermediate loudnesses.

27. The method of claim 25, wherein the decompressing of the audio comprises:

decompressing the audio by converting the audio into a pulse code modulation file.

28. The method of claim 27, further comprising the additional step of:

performing automatic gain control on the pulse code modulation file prior to identifying the dialog.

29. The method of claim 25, further comprising the additional step of:

filtering the audio.

30. The method of claim 25, further comprising the additional step of:

correcting compression of the audio.

31. A system for correcting an audio level of a stored program asset, the system comprising:

means for retrieving a stored program asset, the asset having audio encoded at a DIALNORM setting;

means for identifying dialog of the asset;

means for determining a DIALNORM of the dialog; and

means for re-encoding the asset at a loudness setting corresponding to the determined DIALNORM of the dialog, if the DIALNORM setting and the determined DIALNORM of the dialog are different by more than a predetermined amount.

32. The system of claim 31, further comprising:

means for storing the asset.

33. A system for correcting an audio level of a stored program asset, the system comprising:

memory to store the program asset, the asset having audio encoded at a DIALNORM setting; and

a processor coupled to the memory, the processor being programmed to;

retrieve the stored program asset;

identify dialog of the asset;

determine a DIALNORM of the dialog; and

re-encode the asset at a loudness setting corresponding to the determined DIALNORM of the dialog, if the DIALNORM setting and the determined DIALNORM of the dialog are different by more than a predetermined amount.

34. The system of claim 33, wherein the processor is programmed to identify the dialog by:

dividing the audio into time intervals;

determining a loudness of each time interval; and

identifying time intervals with intermediate loudnesses.

35. The method of claim 34, wherein the processor is programmed to:

determine the loudness of each time interval based on psycho-acoustic criteria.

36. The system of claim 35, wherein the processor is programmed to:

determine the loudness based on Leq (A).

37. The system of claim 34, wherein the processor is programmed to:

determine a loudness of the time intervals having the intermediate loudnesses.

38. The system of claim 33, wherein the processor is programmed to:

correct compression of the audio of the program.

39. The system of claim 33, wherein the processor is further programmed to:

receive the program from a source;

store the program in memory for later transmission; and

retrieve the program from memory.

40. The system of claim 33, wherein the processor is further programmed to:

demultiplex the audio from the program.

41. The system of claim 33, wherein the processor is further programmed to:

decompress the audio.

42. The system of claim 41, wherein the processor is further programmed to:

decompress the audio by converting the audio to a pulse coded modulation format.

43. The system of claim 33, wherein the processor is further programmed to:

perform automatic gain control on the audio prior to identifying the DIALNORM setting and loudness setting.

44. The system of claim 33, wherein the processor is further programmed to:

filter the audio.

45. The system of claim 33, wherein the processor is further programmed to identify the dialog by:

filtering the audio.

46. A method of encoding audio of a program, comprising:

receiving a program, the program having audio encoded at a DIALNORM setting;

identifying dialog of the program;

determining a DIALNORM of the dialog;

comparing the determined DIALNORM of the dialog to the DIALNORM setting; and

encoding the program for storage at a loudness setting corresponding to the determined DIALNORM of the dialog, if the DIALNORM setting and the determined DIALNORM of the dialog are different by more than a predetermined amount.

47. The method of claim 46, wherein the identifying of the dialog comprises identifying the dialog by:

dividing the audio into time intervals as the audio is received;

determining a loudness of each time interval as the interval is divided; and

identifying time intervals with intermediate loudness after at least a portion of the audio of the entire program is received.

48. The method of claim 47, wherein the determining of the loudness of each time interval comprises determining the loudness of each time interval based on psychoacoustic criteria.

49. The method of claim 48, wherein the determining of the loudness of each time interval comprises determining the loudness of each time interval based on Leq (A).

50. The method of claim 47, further comprising:

normalizing the determined loudness of the time intervals having intermediate loudnesses.

51. The method of claim 50, wherein the normalized determined loudness is evaluated by:

determining a DIALNORM of the time intervals having intermediate loudnesses.

52. The method of claim 47, wherein said program is less than a predetermined length of time, and wherein said step of identifying said time intervals with said intermediate loudnesses is deferred until substantially all of said program has been received.

53. The method of claim 52, wherein said predetermined length of time is about one hour.

54. The method of claim 47, wherein said program is greater than a predetermined length of time, and wherein said step of identifying said time intervals with said intermediate loudnesses is carried out after said predetermined length of time has elapsed, but prior to receiving all of said program.

55. The method of claim 54, wherein said predetermined length is about one hour.

56. A system for encoding audio of a program, comprising:

a receiver to receive a program, the program having audio encoded at a DIALNORM setting; and

a processor programmed to;

identify dialog of the program;

determine a DIALNORM of the dialog;

compare the determined DIALNORM of the dialog to the DIALNORM setting; and

encode the program for storage at a loudness setting corresponding to the determined DIALNORM of the dialog, if the DIALNORM setting and the determined DIALNORM of the dialog are different by more than a predetermined amount.