Method and system for producing formatted data related to geometric distortions

• US 20040240750A1
• Filed: 06/08/2004
• Published: 12/02/2004
• Est. Priority Date: 07/12/2001
• Status: Active Grant

• Current Assignee: Lens Correction Technologies Corporation
• Original Assignee: DXO Labs
• Inventors: Guichard, Frederic, Liege, Bruno, Lavest, Jean-Marc, Chauville, Benoit
• Granted Patent: US 7,532,766 B2
• Time in Patent Office: Days
• US Class Current: 382/275
• CPC Class Codes: G06T 1/0007 Image acquisition
• CPC Class Codes: H04N 1/387 Composing, repositioning or otherwise geometrically modifying originals
• CPC Class Codes: H04N 1/58 Edge or detail enhancement; Noise or error suppression, e.g. colour misregistration correction H04N1/62 takes precedence

Abstract

The invention relates to a processing system and method for producing formatted information related to the appliances (APP1 to 3) of an appliance chain (APP1). This appliance chain comprises in particular at least one image-capture appliance (APP1) and/or at least one image-restitution appliance (App3) for capturing and/or restituting an image (M) on a medium (SC). The invention aims at producing formatted information related to the geometric distortions of at least one appliance of the said chain. The invention provides different alternative embodiments, especially that with which fixed characteristics of the appliances and/or variable characteristics depending on the image (I) can be taken into account. The fixed characteristics and/or the variable characteristics are capable of being associated with one or more characteristic values, especially the focal length and/or the focusing. The invention then provides for producing measured formatted information related to the geometric distortions of the said appliance from a measured field D(H). The invention is applicable to photographic or video image processing, in optical devices, industrial controls, robotics, metrology, etc.

Claims

1-30. -30. (Canceled).

31. A method for producing formatted information related to appliances of an appliance chain, the appliance chain including at least one image-capture appliance and/or at least one image-restitution appliance, the method comprising:

producing formatted information related to geometric distortions of at least one appliance of the appliance chain.

32. A method according to claim 31, wherein the appliance is configured to capture or restitute an image on a medium, the appliance containing at least one fixed characteristic and/or one variable characteristic depending on the image, the fixed characteristic and/or variable characteristic configured to be associated with one or more values of characteristics, and values of associated characteristics;

the method further comprising;

producing, from a measured field, measured formatted information related to geometric distortions of the appliance, the formatted information configured to include the measured formatted information.

33. A method according to claim 32, further comprising:

producing extended formatted information related to geometric distortions of the appliance from the measured formatted information, the formatted information configured to include the extended formatted information, the extended formatted information exhibiting a deviation compared with the measured formatted information.

34. A method according to claim 33, wherein the formatted information produced from the measured formatted information is represented by parameters of a parameterizable model chosen from among a set of parameterizable models,

the method further comprising:

selecting the parameterizable model within the set of parameterizable models by;

defining a maximum deviation,

ordering the parameterizable models of the set of parameterizable models in accordance with their degree of complexity of employment,

choosing a first of the parameterizable models of the ordered set of parameterizable models such that the deviation is smaller than the maximum deviation.

35. A method according to claim 33, wherein the extended formatted information is the measured formatted information.

36. A method according to claim 33, including a first calculation algorithm with which the measured field can be obtained from a universal set containing characteristic points and from a virtual reference composed of reference points on a reference surface;

the first calculation algorithm including capturing or restituting the universal set by the appliance to produce an image of the characteristic points on the medium as a characteristic image point;

the first calculation algorithm further including;

establishing a bijection between the characteristic image point and the reference points,

selecting zero or one or more variable characteristics among the set of the variable characteristics;

the measured field being composed of;

the set of pairs composed of one of the reference points and of the characteristic image point associated by the bijection, and

the value, for the image, of each of the selected variable characteristics.

37. A method according to claim 36, further comprising:

choosing a mathematical projection, between the medium and the reference surface;

wherein the measured field is composed of the value, for the image, of each of the selected variable characteristics and, for each reference point;

of the pair composed of the reference point and of the mathematical projection, onto the reference surface, of the characteristic image point associated by the bijection with the reference point, and/or

of the pair composed of the characteristic image point associated by the bijection with the reference point, and of the mathematical projection of the reference point onto the medium.

38. A method according to claim 36, further comprising:

obtaining, from the measured formatted information, the extended formatted information related to an arbitrary reference point on the reference surface and/or related to an arbitrary characteristic image point of the medium, by deducing the formatted information related to the arbitrary reference point or to the arbitrary characteristic image point.

39. A method according to claim 33, wherein the appliance of the appliance chain is provided with at least one variable characteristic depending on the image, each variable characteristic configured to be associated with a value to form a combination composed of the set of the variable characteristics and of the values;

the method further comprising;

selecting predetermined combinations; and

calculating measured formatted information, including employing the first calculation algorithm for each of the selected predetermined combinations.

40. A method according to claim 39, wherein an argument is defined, depending on a case, as:

an arbitrary reference point on the reference surface and a combination, or

an arbitrary characteristic image point of the medium and a combination;

the method further comprising;

deducing, from the measured formatted information, the extended formatted information related to an arbitrary argument.

41. A method according to claim 38, wherein to deduce the extended formatted information from the measured formatted information:

a first threshold is defined,

the extended formatted information is selected such that the deviation is below the first threshold.

42. A method according to claim 33, further comprising:

associating the deviations with the formatted information.

43. A method according to claim 36, further comprising:

selecting, on the medium, four characteristic image points such that a quadrilateral defined by the four characteristic image points has a maximum area and a center of gravity situated in proximity of the geometric center of the image, the mathematical projection being a bilinear transformation that transforms the four characteristic image points to the reference points associated by bijection with the four characteristic image points.

44. A method according to claim 36, wherein the image is a color image composed of a plurality of color planes;

the method further comprising;

producing the measured formatted information by employing the first calculation algorithm for at least two of the color planes, by using a same mathematical projection for each of the color planes.

45. A method according to claim 36, wherein the image is a color image composed of a plurality of color planes;

the method further comprising;

producing the measured formatted information by employing the first calculation algorithm for at least one of the color planes, by using a same virtual reference for each of the color planes;

wherein the formatted information and/or measured formatted information can correct chromatic aberrations of the appliance.

46. A system for producing formatted information related to appliances of an appliance chain, the appliance chain including at least one image-capture appliance and/or at least one image-restitution appliance, the system comprising:

calculating means for producing formatted information related to geometric distortions of at least one appliance of the chain.

47. A system according to claim 46, wherein the appliance is configured to capture or restitute an image on a medium, the appliance containing at least one fixed characteristic and/or one variable characteristic depending on the image, the fixed characteristic and/or variable characteristic configured to be associated with one or more values of characteristics, and values of associated characteristics;

the system further comprising;

calculating means for producing, from a measured field, measured formatted information related to the geometric distortions of the appliance, the formatted information configured to include the measured formatted information.

48. A system according to claim 47, further comprising:

calculating means for producing extended formatted information related to geometric distortions of the appliance from the measured formatted information, the formatted information configured to include the extended formatted information, the extended formatted information exhibiting a deviation compared with the measured formatted information.

49. A system according to claim 48, wherein the formatted information produced from the measured formatted information is represented by parameters of a parameterizable model chosen from among a set of parameterizable models;

the system further comprising;

selection means for selecting the parameterizable model within the set of parameterizable models, the selection means including data-processing means for;

defining a maximum deviation,

ordering the parameterizable models of the set of parameterizable models in accordance with their degree of complexity of employment,

choosing a first of the parameterizable models of the ordered set of parameterizable models such that the deviation is smaller than the maximum deviation.

50. A system according to claim 48, wherein the extended formatted information is the measured formatted information.

51. A system according to claim 48, further comprising:

calculating means employing a first calculation algorithm with which the measured field can be obtained from a universal set containing characteristic points and from a virtual reference composed of reference points on a reference surface;

the image-capture appliance or the image-restitution appliance including means for capturing or means for restituting the universal set, with which means an image of the characteristic points can be produced on the medium as a characteristic image point;

the means for calculation of the first calculation algorithm further including data-processing means for;

establishing a bijection between the characteristic image point and the reference points,

selecting zero or one or more variable characteristics, among the set of the variable characteristics;

the measured field being composed of;

the set of pairs composed of one of the reference points and of the characteristic image point associated by the bijection, and

the value, for the image, of each of the selected variable characteristics.

52. A system according to claim 51, further comprising:

analysis means for choosing a mathematical projection, between the medium and the reference surface;

the measured field being composed of the value, for the image, of each of the selected variable characteristics and, for each reference point;

of the pair composed of the reference point and of the mathematical projection, onto the reference surface, of the characteristic image point associated by the bijection with the reference point, and/or

of the pair composed of the characteristic image point associated by the bijection with the reference point, and of the mathematical projection of the reference point onto the medium.

53. A system according to claim 51, further comprising:

data-processing means for obtaining, from the measured formatted information, the extended formatted information related to an arbitrary reference point on the reference surface and/or related to an arbitrary characteristic image point of the medium, by deducing the formatted information related to the arbitrary reference point or to the arbitrary characteristic image point.

54. A system according to claim 48, wherein the appliance of the appliance chain is provided with at least one variable characteristic depending on the image, each variable characteristic configured to be associated with a value to form a combination composed of the set of the variable characteristics and of the values;

the system further comprising;

selection means for selecting predetermined combinations; and

calculating means for calculating measured formatted information, by employing the first calculation algorithm for each of the selected predetermined combinations.

55. A system according to claim 54, wherein an argument designates, depending on a case:

an arbitrary reference point on the reference surface and a combination, or

an arbitrary characteristic image point of the medium and a combination;

the system further comprising;

data-processing means for deducing, from the measured formatted information, the extended formatted information related to an arbitrary argument.

56. A system according to claim 53, wherein to deduce the extended formatted information from the measured formatted information, the data-processing means includes selection means for selecting the extended formatted information such that the deviation is below a first threshold.

57. A system according to claim 48, wherein the deviations are associated with the formatted information.

58. A system according to claim 51, further comprising:

selection means for selecting, on the medium, four characteristic image points such that a quadrilateral defined by the four characteristic image points has a maximum area and a center of gravity situated in proximity of a geometric center of the image, the mathematical projection being a bilinear transformation that transforms the four characteristic image points to the reference points associated by the bijection with the four characteristic image points.

59. A system according to claim 51, wherein the image is a color image composed of a plurality of color planes;

the system further comprising;

data-processing means for producing the measured formatted information by employing the first calculation algorithm for at least two of the color planes, by using a same mathematical projection for each of the color planes;

wherein the formatted information and/or measured formatted information can correct distortions and/or chromatic aberrations of the appliance.

60. A system according to claim 51, wherein the image is a color image composed of a plurality of color planes;

the system further comprising;

data-processing means for producing the measured formatted information by employing the first calculation algorithm for at least one of the color planes, by using a same virtual reference for each of the color planes;

wherein the formatted information and/or measured formatted information can correct chromatic aberrations of the appliance.