Methods and Systems for Tone Mapping Messaging

• US 20070223813A1
• Filed: 12/04/2006
• Published: 09/27/2007
• Est. Priority Date: 03/24/2006
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Kerofsky, Louis Joseph, Segall, Christopher A., Lei, Shawmin
• Granted Patent: US 8,194,997 B2
• Time in Patent Office: Days
• US Class Current: 382/166
• CPC Class Codes: H04N 1/6027 Correction or control of colour gradation or colour contrast H04N1/6058 takes precedence

Abstract

Embodiments of the present invention comprise methods and systems for signaling tone map data to an image recipient.

Claims

1. A system for converting an image from a first dynamic range to a second dynamic range, said system comprising:

a. a receiver for receiving an image and for receiving a message, wherein said message comprises;

i) a plurality of tone maps for use in converting an image from a first dynamic range to a second dynamic range, wherein each of said tone maps is defined by a model identifier (ID) and at least one model parameter, and each of said tone maps is associated with a tone map ID, which identifies the purpose of the associated tone map;

b. a selector for selecting a first tone map, from said plurality of tone maps, to apply to said image; and

c. a tone map processor for applying said first tone map to said image, thereby producing a tone-mapped image.

2. A system as described in claim 1, wherein said plurality of tone maps comprises a linear map with clipping, a sigmoidal map, a user-defined lookup table map, and a piecewise linear map.

3. A system as described in claim 1 further comprising a transmitter for transmitting said tone-mapped image.

4. A system as described in claim 1, wherein said message is a Supplemental Enhancement Information (SEI) message.

5. A system as described in claim 1, wherein said message further comprises a tone map cancel flag for canceling the persistence of a previous tone map message.

6. A system as described in claim 1, wherein said message further comprises a tone map repetition period message.

7. A system as described in claim 1, wherein said message allows said selector to select said first tone map so that said first tone map corresponds to a recipient device dynamic range.

8. A system as described in claim 1, wherein said selector selects said first tone map according to at least one recipient preference.

9. A method for converting an image from a first dynamic range to a second dynamic range, said method comprising:

a. receiving a message, wherein said message comprises at least one tone map model identifier (ID), wherein each of said at least one tone map model IDs is associated with a tone map, and said message further comprises, for each of said at least one tone map model IDs, at least one model parameter for said associated tone map;

b. determining a first tone map to apply to an image with a first dynamic range from said at least one tone map, wherein said first tone map maps said first dynamic range to a second dynamic range;

c. constructing said first tone map using said at least one model parameter associated with said first tone map; and

d. applying said first tone map to said image, thereby producing an image with said second dynamic range.

10. A method as described in claim 9, wherein said second dynamic range corresponds to a recipient device dynamic range.

11. A method as described in claim 9, wherein said message allows said determining to be based on recipient preferences.

12. A method as described in claim 9, wherein said message is a Supplemental Enhancement Information (SEI) message.

13. A method as described in claim 9, wherein said message further comprises a tone map ID for each of said at least one tone maps, wherein said tone map ID identifies a dynamic range for said tone map.

14. A method as described in claim 9, wherein said tone map represented by said at least one tone map model ID is a tone map selected from the group consisting of a linear map with clipping, a sigmoidal map, a user-defined lookup table map, and a piecewise linear map.

15. A method as described in claim 9, wherein said message further comprises a tone map cancel flag for canceling the persistence of a previous tone map message.

16. A method as described in claim 9, wherein said message further comprises a tone map repetition period message.

17. A method as described in claim 9 further comprising receiving a bitstream, wherein said bitstream comprises said image with said first dynamic range.

18. A method as described in claim 17, wherein said bitstream further comprises said message.

19. A method as described in claim 9 further comprising transmitting said image with said second dynamic range.

20. A method as described in claim 17 further comprising transmitting said image with said second dynamic range.

21. A method for signaling tone map data from an image encoder to an image recipient, said method comprising:

a. establishing at least one tone map for use in converting an image from a first dynamic range to a second dynamic range;

b. representing each of said at least one tone map with a model identifier (ID) and at least one model parameter; and

c. sending a message to a recipient of said image, wherein said message comprises said tone map model IDs and said at least one model parameters for said at least one tone map, wherein said recipient may use said tone map model IDs and said at least one model parameters to identify said at least one tone map and apply said at least one tone map to said image.

22. A method as described in claim 21 wherein said message is a Supplemental Enhancement Information (SEI) message.

23. A method as described in claim 21 wherein said at least one tone map comprises a linear map with clipping, a sigmoidal map, a user-defined lookup table map and a piecewise linear map.

24. A method as described in claim 21 further comprising a tone map ID for each of said at least one tone maps, wherein said tone map ID identifies a dynamic range for its associated tone map.

25. A method as described in claim 21 wherein said message is transmitted outside the bitstream in which said image is transmitted.

26. A method as described in claim 21 wherein said message further comprises a tone map cancel flag for canceling the persistence of a previous tone map message.

27. A method as described in claim 21 wherein said message further comprises a tone map repetition period message.

28. A method as described in claim 21, wherein said message allows said recipient to select one of said plurality of tone maps that corresponds to a recipient device dynamic range.

29. A method as described in claim 21, wherein said message allows said recipient to select one of said plurality of tone maps that corresponds to at least one recipient preference.