Using surfaces with printed patterns for image and data processing
Adjusting data for photographed images includes detecting a reference image in the data, where the reference image contains a detectable uniformity and adjusting the data according to the reference image. The reference image may be a uniform grid pattern of dots preprinted on paper. A paper type may be determined prior to adjusting the data according to the reference image. The paper type may be determined according to spacing and/or patterns of the dots, and/or layout of page areas covered with dots. Adjusting the data may include removing effects corresponding to a folded corner, a removed corner, an obstructed corner, lens flare spots, and/or a shadow. Positional coordinates of the data may be adjusted by normalizing the grid through a non-linear transformation that eliminates curvature of the grid and/or distortions based on perspective.
1. A method of adjusting data for photographed images, comprising:
detecting in the data a reference image that is a uniform grid pattern of dots preprinted on page areas of paper; and
adjusting the data according to the reference image, wherein prior to adjusting the data according to the reference image, page boundaries are determined by extrapolating detected gridlines to an expected count of gridlines.
2. A method, according to claim 1 , wherein the expected count of gridlines varies according to at least one of: spacing and patterns of the dots, and layout of the page areas covered with dots.
3. A method, according to claim 1 , wherein adjusting the data includes removing effects corresponding to at least one of: a folded corner, a removed corner, and an obstructed corner.
4. A method, according to claim 1 , wherein positional coordinates of the data are adjusted by normalizing the grid through a non-linear transformation that eliminates at least one of: curvature of the grid and distortions based on perspective.
5. A method, according to claim 1 , wherein initial page boundaries are adjusted after perspective distortions have been eliminated.
6. A method, according to claim 1 , wherein the photographed image is handwritten notes on the preprinted paper that are photographed using a mobile phone.
7. A method, according to claim 6 , further comprising:
removing the grid pattern in connection with adjusting the data.
8. A method, according to claim 1 , wherein color and brightness correction is performed by comparing color and brightness of the paper and dots with ideal brightness values for the paper and dots.
9. A method, according to claim 8 , wherein ideal brightness of the ink is determined through calculations based on brightness values of the paper and the dots for the particular paper type.
10. A method, according to claim 1 , wherein the reference image has a pre-defined color that is used for color correction.
11. A method, according to claim 1 , wherein detecting a reference image includes a reverse image search and content-based image retrieval techniques.
12. A method, according to claim 11 , wherein a content-based image retrieval technique is selected from the group consisting of: TinEye, Imprezzeo, and Macroglossa.
13. A method, according to claim 1 , wherein adjusting the data includes removing effects corresponding to at least one of: lens flare spots and a shadow.
14. Computer software, provided in a non-transitory computer-readable medium, that adjusts data for photographed images, the software comprising:
executable code that detects in the data a reference image that is a uniform grid pattern of dots preprinted on page areas of paper; and
executable code that adjusts the data according to the reference image, wherein a prior to adjusting the data according to the reference image, page boundaries are determined by extrapolating detected gridlines to an expected count of gridlines.
15. Computer software, according to claim 14 , wherein the expected count of gridlines varies according to at least one of: spacing and patterns of the dots, and layout of the page areas covered with dots.
16. Computer software, according to claim 14 , wherein adjusting the data includes removing effects corresponding to at least one of: a folded corner, a removed corner, and an obstructed corner.
17. Computer software, according to claim 14 , wherein positional coordinates of the data are adjusted by normalizing the grid through a non-linear transformation that eliminates at least one of: curvature of the grid and distortions based on perspective.
18. Computer software, according to claim 14 , wherein initial page boundaries are adjusted after perspective distortions have been eliminated.
19. Computer software, according to claim 14 , wherein the photographed image is handwritten notes on the preprinted paper that are photographed using a mobile phone.
20. Computer software, according to claim 19 , further comprising:
executable code that removes the grid pattern in connection with adjusting the data.
21. Computer software, according to claim 14 , wherein color and brightness correction is performed by comparing color and brightness of the paper and dots with ideal brightness values for the paper and dots.
22. Computer software, according to claim 21 , wherein ideal brightness of the ink is determined through calculations based on brightness values of the paper and the dots for the particular paper type.
23. Computer software, according to claim 14 , wherein the reference image has a pre-defined color that is used for color correction.
24. Computer software, according to claim 14 , wherein detecting a reference image includes a reverse image search and content-based image retrieval techniques.
25. Computer software, according to claim 24 , wherein a content-based image retrieval technique is selected from the group consisting of: TinEye, Imprezzeo, and Macroglossa.
26. Computer software, according to claim 14 , wherein the software is one of: pre-loaded with a device, installed from an application store, and downloaded from a location of a network operator.
27. Computer software, according to claim 14 , wherein adjusting the data includes removing effects corresponding to at least one of: lens flare spots and a shadow.