System and method for creating a virtual backdrop

1. A method for generating a portrait of a subject for an identification document, the method comprising:

receiving a photo image of the subject, the photo image including the subject's face in a foreground against an arbitrary background;

estimating the foreground and the background of the photo image by an image matting process that includes determining a probability of each pixel being a boundary pixel that is between the foreground and the arbitrary background, wherein the estimation is without calibrating a portion from the photo image against a portion from an additional photo image that includes either the subject or the arbitrary background;

masking the estimated background from the photo image; and

subsequently generating the portrait of the subject for the identification document of the subject, the portrait being based on the photo image with the estimated background masked.

2. The method of claim 1 , further comprising: masking the determined background without storing data encoding the determined background.

3. The method of claim 1 , further comprising: determining the arbitrary background that is without a substantially uniform illumination or color.

4. The method of claim 1 , wherein generating the portrait of the subject further comprises: resizing portions of the foreground that correspond to the subject's face.

5. The method of claim 1 , wherein generating the portrait of the subject further comprises: synthesizing a virtual backdrop in the generated portrait by replacing the masked background with a synthetic background, the synthetic background comprising a pattern pre-determined for the identification document.

6. The method of claim 5 , further comprising: integrating the generated portrait with the synthesized virtual background on the identification document to identify the subject.

7. The method of claim 1 , wherein generating the portrait of the subject further comprises: adjusting a region of interest of the subject's hair volume in the foreground.

8. The method of claim 1 , further comprising: providing a user interface to allow a user to adjust a region of interest of the subject's hair volume in the foreground.

9. The method of claim 1 , further comprising: providing a user interface to allow a user to select a particular location in the photo image when the determined background has been masked and subsequently adjust corresponding color or brightness of the selected particular location in the photo image.

10. The method of claim 1 , wherein generating the portrait further comprises: tracing a boundary that separates the foreground from the arbitrary background.

11. The method of claim 10 , wherein generating the portrait of the subject further comprises: providing a user interface to allow a user to trace a boundary that separates the foreground from the arbitrary background.

12. A computer system, comprising at least one processor configured to:

receive a photo image of the subject, the photo image including the subject's face in a foreground against an arbitrary background;

estimate the foreground and the background of the photo image by an image matting process that includes determining a probability of each pixel being a boundary pixel that is between the foreground and the arbitrary background, wherein the estimation is without calibrating a portion from the photo image against a portion from an additional photo image that includes either the subject or the arbitrary background;

mask the estimated background from the photo image; and

subsequently generate the portrait of the subject for the identification document of the subject, the portrait being based on the photo image with the estimated background masked.

13. The computer system of claim 12 , wherein the at least one processor is further configured to determine the arbitrary background by transmitting the photo image of the subject to a server for making the determination.

14. The computer system of claim 12 , wherein determining the arbitrary background further comprises: determining the arbitrary background that is without a substantially uniform illumination or color.

15. The computer system of claim 12 , wherein the at least one processor is further configured to generate the portrait of the subject by resizing portions of the foreground that correspond to the subject's face.

16. The computer system of claim 12 , wherein the at least one processor is further configured to generate the portrait of the subject for the identification document of the subject by replacing the masked background with a synthetic background, the synthetic background comprising a pattern pre-determined for the identification document.

17. The computer system of claim 16 , wherein the at least one processor is further configured to integrate the generated portrait on the identification document to identify the subject.

18. The computer system of claim 16 , wherein the at least one processor is further configured to replace the masked background without storing information encoding the determined background.

19. The computer system of claim 12 , further comprising: a camera device to adapted capture the photo image of the subject with the arbitrary background.

20. The computer system of claim 12 , wherein the at least one processor is further configured to: adjust a region of interest of the subject's hair volume in the foreground.

21. The computer system of claim 12 , wherein the at least one processor is further configured to: provide a user interface to allow a user to adjust a region of interest of the subject's hair volume in the foreground.

22. The computer system of claim 13 , wherein the at least one processor is further configured to: provide a user interface to allow a user to select a particular location in the photo image with the background masked and adjust corresponding color or brightness of the selected particular location in the photo image.

23. The computer system of claim 12 , wherein the at least one processor is further configured to: trace a boundary that separates the foreground from the arbitrary background.

24. The computer system of claim 12 , wherein the at least one processor is further configured to: providing a user interface to allow a user to trace a boundary that separates the foreground from the arbitrary background.

25. A non-transitory computer-readable medium comprising software instructions that when executed by one or more processors, cause the one or more processors to perform the operations of:

receiving a photo image of the subject, the photo image including the subject's face in a foreground against an arbitrary background;

estimating the foreground and the background of the photo image by an image matting process that includes determining a probability of each pixel being a boundary pixel that is between the foreground and the arbitrary background, wherein the estimation is without calibrating a portion from the photo image against a portion from an additional photo image that includes either the subject or the arbitrary background;

masking the estimated background from the photo image; and

subsequently generating the portrait of the subject for the identification document of the subject, the portrait being based on the photo image with the estimated background masked.

26. The computer-readable medium of claim 25 , wherein determining the arbitrary background further comprises: determining the arbitrary background that is without a substantially uniform illumination or color.

27. The computer-readable medium of claim 25 , wherein generating the portrait of the subject comprises: synthesizing a virtual backdrop in the generated portrait by replacing the masked background with a synthetic background, the synthetic background comprising a pattern pre-determined for the identification document.

28. The computer-readable medium of claim 25 , wherein the operations further comprise integrating the generated portrait on the identification document to identify the subject.

29. The computer-readable medium of claim 25 , wherein the operations further comprise replacing the masked background without storing data encoding the determined background.

30. The method of claim 1 , wherein estimating the foreground of the photo image further comprises:

down-sampling the photo image; and

performing a sparse foreground estimation.

31. The method of claim 30 , wherein masking the estimated background from the photo image further comprises:

up-sampling a boundary between the estimated foreground and background, wherein the boundary comprises at least one boundary pixel with a determined probability above a threshold.

32. The computer system of claim 12 , wherein the at least one processor is configured to estimate the foreground of the photo image by:

down-sampling the photo image; and

performing a sparse foreground estimation.

33. The computer system of claim 32 , wherein the at least one processor is configured to mask the estimated background from the photo image by:

up-sampling a boundary between the estimated foreground and background, wherein the boundary comprises at least one boundary pixel with a determined probability above a threshold.

34. The computer-readable medium of claim 25 , wherein estimating the foreground of the photo image further comprises:

down-sampling the photo image; and

performing a sparse foreground estimation.

35. The computer-readable medium of claim 34 , wherein masking the estimated background from the photo image further comprises:

up-sampling a boundary between the estimated foreground and background, wherein the boundary comprises at least one boundary pixel with a determined probability above a threshold.