Method and apparatus for lightness imaging
First Claim
1. Apparatus for producing an image of a subject which comprisesA. means for detecting radiance ratios between different areas of said subject and producing a first lightness-determining quantity in response to each such ratio,B. means for effecting said ratio detection for each area of said subject a multiple number of times with other areas of said subject which are at different locations on said subject relative to that area,C. means for combining each first lightness-determining quantity with a second lightness-determining quantity associated with one area in that ratio and replacing the second lightness-determining quantity associated with another area in that ratio in response thereto, andD. means for producing an image of the subject in which the lightness of the respective image areas is determined by the last replacement values of said second lightness-determining quantities.
1 Assignment
0 Petitions
Accused Products
Abstract
This invention provides mechanisms that detect the large dynamic range of radiant intensities in the natural environment, that use novel strategies to calculate an approximation of visual properties of objects, and that represent a scene with an image having a specific dynamic range that is optimal for display media such as photography, television and printing.
Photographs and other images are made according to the foregoing mechanisms from lightness fields produced from multiple comparisons between information associated with a different segmental areas of an image field. Different comparisons involve different groups of segmental areas, and different groupings have at least one spatial parameter different from other groupings of areas. Comparisons advantageously are made in succession with an ordered sequence of the spatial parameter and employing results of prior comparisons.
-
Citations
86 Claims
-
1. Apparatus for producing an image of a subject which comprises
A. means for detecting radiance ratios between different areas of said subject and producing a first lightness-determining quantity in response to each such ratio, B. means for effecting said ratio detection for each area of said subject a multiple number of times with other areas of said subject which are at different locations on said subject relative to that area, C. means for combining each first lightness-determining quantity with a second lightness-determining quantity associated with one area in that ratio and replacing the second lightness-determining quantity associated with another area in that ratio in response thereto, and D. means for producing an image of the subject in which the lightness of the respective image areas is determined by the last replacement values of said second lightness-determining quantities.
-
2. Image processing apparatus for determining a field of accumulating measures of image lightness in response to information identifying optical radiance associated with arrayed sections of an image field, said apparatus having the improvement comprising
A. means for sequentially determining a comparative measure of the radiance information for each segmental area of said image field relative to said information for each of plural other segmental areas, said means (i) providing a new intermediate value of each such measure in response to the product of a ratio function of the radiance information associated with each first-named segmental area and with each second-named segmental area and of a like measure previously determined for the second-named segmental area, and (ii) determining a sequentially new value of each said measure in response to a selectively weighted averaging of said new intermediate value and a like measure previously determined for said first-named segmental area, and B. means for the prior measure for each first-named segmental area in response to said newly-determined value, thereby to determine each measure in the field thereof in response to an accumulating succession of said measures.
-
4. Image processing apparatus for determining a field of accumulating measures of image lightness in response to information identifying optical radiance associated with an image field, said apparatus having the improvement comprising
A. means for sequentially determining a comparative measure of the radiance information for each segmental area of said image field relative to said information for each of plural other segmental areas of that field, said means (i) providing a new intermediate value of each such comparative measure in response to the product of a ratio function of the radiance information associated with each first-named segmental area and with each second-named segmental area and of a like measure previously determined for the second-named segmental area, and further providing each such intermediate value with reference to a selected condition of said product, and (ii) determining a sequentially new value of each said comparative measure in response to a selectively weighted averaging of said new intermediate value and a like measure previously determined for said first-named segmental area, and B. means for replacing the previously determined measure for each first-named segmental area in response to said sequentially-determined new value, thereby to determine each measure in the field in response to an accumulating succession of said comparative measures.
-
7. Image processing apparatus for determining information corresponding to image lightness in response to radiance-identifying information for a selected image field, said apparatus having the improvement comprising
A. means for representing the radiance-identifying information for each of selected segmental areas of the viewing field, B. means for determining a selected comparison measure between said identifying information for each segmental area and said information for another segmental area, and for determining therefrom and from a previously-determined lightness-identifying quantity for each latter segmental area a newly-determined lightness-identifying quantity for each former segmental area, C. means for effecting a selected multiple of said determinations sequentially and between segmental areas that correspond to differently-spaced locations in said field of view, and D. means for producing said lightness-information for said image field in response to said multiple determinations.
-
13. Image processing apparatus for determining information corresponding to image lightness in response to radiance-identifying information for a selected image field, said apparatus having the improvement comprising
A. means for representing said radiance-identifying information for each of selected segmental areas of the viewing field, B. means for determining a selected comparison measure between said identifying information for each segmental area and said information for another segmental area, and for determining therefrom and from a previously-determined lightness-identifying quantity for each latter segmental area a newly-determined lightness-identifying quantity for each former segmental area, said means for determining including means for effecting a determination of said measure for each of a selected plurality of areas prior to effecting a further such determination for an area of that plurality, C. means for effecting a selected multiple of said determinations for said plurality of areas sequentially, different ones of said sequential determinations being between segmental areas having a spatial parameter different from that of the areas of other such determinations, and for applying each newly-determined quantity of one determination as a previously-determined quantity in a subsequent determination, and further including means for ordering said determinations according to the magnitude of said spatial parameter, and D. means for producing said lightness-information for said image field in response to said multiple determinations.
-
14. Lightness-imaging apparatus having means for providing information identifying optical radiance associated with arrayed sections of a selected image field, said apparatus further comprising
A. means for selectively grouping segmental areas of said image field a selected number of times, different ones of at least some of said groupings involving areas having at least one spatial parameter different from other groupings of areas, B. means for providing, for each grouping of segmental area, at least one measure of visually significant transition in said radiance information between areas of that grouping, said measures being with reference to a selected lightness condition, and C. means for determining image lightness for each arrayed section of the image field in response to a plurality of said measures, at least some of which are provided for groupings which differ from one another in at least one spatial parameter.
-
30. In lightness-imaging apparatus having
(i) means for providing information identifying optical radiance associated with each arrayed section of a selected image field, (ii) means for selectively pairing segmental areas of said image field a selected number of times, each said pairing being of segmental areas of identical configuration and size, (iii) means for providing, for each pairing of segmental areas, at least one comparative measure of said radiance information at the paired areas, and (iv) means for resetting each said measure with reference to a selected limit condition, the improvement comprising means for determining image lightness for each arrayed section of the image field in response to a plurality of said reset measures, at least some of which are provided for pairings which differ from one another in at least one spatial parameter.
-
39. Image processing apparatus comprising
A. first and second signal addder means, B. first and second delay means, each arranged to apply signals output therefrom to an input of the same-numbered adder means, C. first and second signal transformation means, each arranged to apply signals output therefrom to a further input of the same-numbered adder means, said first transformation means having a polarity inversion function and said second transformation means having a reset function and being arranged to receive signals output from said first adder means, D. first memory means arranged to apply signals read therefrom to said first transformation means and to said first delay means, E. second memory means arranged to apply signals read therefrom to a further input of said first adder means and to said second delay means, F. further signal transformation means having a compress function and arranged to receive signals from said second added means and to apply signals to an input of said second memory means, and G. control means for controlling said adder means, delay means, transformation means and memory means for applying signals to said first adder means from said first transformation means and from said first delay means and from said second memory means with selected relative timing, and to apply signals to said second adder means from said second transformation means and from said second delay means with selected timing relative to one another and relative to said application of signals to said first adder means.
-
40. Lightness-imaging apparatus having means for providing information identifying optical radiance associated with arrayed sections of a selected image field, said apparatus further comprising
A. means for pairing identically configured and sized segmental areas of said viewing field differently a number of times and for providing a multiple of sets of said different pairings, each said set involving areas of a size different from other sets, B. means for providing, for each pairing of segmental areas, a comparative measure of said radiance information at the paired areas, C. means for resetting each said measure with reference to a selected limit, and D. means for determining image lightness for each arrayed section of the image field in response to a plurality of said reset measures.
-
43. Lightness-imaging apparatus having means for providing information identifying optical radiance associated with each arrayed section of a selected image field, said apparatus further comprising
A. means for selectively pairing segmental areas of said image field a selected number of times, each said pairing being of segmental areas of identical configuration and size, B. means for providing, for each pairing of segmental areas, at least one measure of transition in said radiance information between the paired areas, said measure conforming to the equation: -
space="preserve" listing-type="equation">log ip(xy)= log op(o,o)+ log r(x,y)- log r(o,o)where log ip(x,y) is the log of the measure for a first segmental area at location (x,y) in the image field relative to a reference location for a second area paired therewith, log op(o,o) is the log of the measure previously assigned to or determined for said second segmental area at said reference location (o,o) in the image field and paired with said first area, and log r(x,y) and log r(o,o) are the logs of the radiance information for said first and second paired areas, respectively, C. means for resetting each said measure with reference to a selected limit, and D. means for determining image lightness for each arrayed section of the image field in response to an arithmetic averaging of a plurality of said reset measures, at least some of which are provided for pairings which differ from one another in at least one spatial parameter.
-
-
44. Lightness-imaging apparatus having means for providing information identifying optical radiance associated with each arrayed section of a selected image field, said apparatus further comprising
A. means for selectively pairing segmental areas of said image field a selected number of times, each said pairing being of segmental areas of identical configuration and size, B. means for providing, for each pairing of segmental areas, at least one measure of transition in said radiance information between the paired areas, said measure conforming to the equation: -
space="preserve" listing-type="equation">log np(x,y)=1/2([log op(x,y)]+[log op(o,o)+log r (x,y)-log r(o,o)])where log np(x,y) is the log of the measure for a first segmental area at location (x,y) in the image field relative to a reference location for a second area paired therewith, log op(x,y) is the log of the measure previously assigned to or determined for said first area, log op(o,o) is the log of the measure previously assigned to or determined for said second segmental area at said reference location (o,o) in the image field and paired with said first area, and log r(x,y) and log r(o,o) are the logs of the radiance information for said first and second paired areas, respectively, and where each said term [log op(o,o)+ log r(x,y)-log r(o,o)] is reset with reference to a selected limit. - View Dependent Claims (45)
-
-
46. A method for producing an image of a subject comprising the steps of
A. detecting radiance ratios between different areas of said subject and producing a first lightness-determining quantity in response to each such ratio, B. effecting said ratio detection for each area of said subject a multiple number of times with other areas of said subject which are at different locations on said subject relative to that area, C. combining each first lightness-determining quantity with a second lightness-determining quantity associated with one area in that ratio and replacing the second lightness-determining quantity associated with another area in that ratio in response thereto, and D. producing an image of the subject in which the lightness of the respective image areas is determined by the last replacement values of said second lightness-determining quantities.
-
47. An image-processing method for determining a field of accumulating measures of image lightness in response to information identifying optical radiance associated with an image field, said method having the improvement comprising the steps of
A. sequentially determining a comparative measure of the radiance information for each segmental area of said image field relative to said information for each of plural other segmental areas, said method-determining step including (i) providing a new intermediate value of each such measure in response to the product of a ratio function of the radiance information associated with each first-named segmental area and with each second-named segmental area and of a like measure previously determined for the second-named segmental area, (ii) determining a sequentially new value of each said measure in response to a selectively weighted averaging of said new intermediate value and a like measure previously determined for said first-named segmental area, and B. updating the previously determined measure for each first-named segmental area in response to said sequentially-determined new value, thereby to determine each measure in the field in response to an accumulating succession of said measures.
-
49. An image processing method for determining a field of accumulating measures of image lightness in response to information identifying optical radiance associated with an image field, said method having the improvement comprising the steps of
A. sequentially determining a comparative measure of the radiance information for each segmental area of said image field relative to said information for each of plural other segmental areas of that field, said measure-determination including (i) providing a new intermediate value of each such comparative measure in response to the product of a ratio function of the radiance information associated with each first-named segmental area and with each second-named segmental area and of a like measure previously determined for the second-named segmental area, and further providing each such intermediate value with reference to a selected condition of said product, and (ii) determining a sequentially new value of each said comparative measure in response to a selectively weighted averaging of said new intermediate value and a like measure previously determined for said first-named segmental area, and B. replacing the previously-determined measure for each first-named segmental area in response to said sequentially new value, thereby to determine each measure in the field thereof in response to an accumulating succession of said comparative measures.
-
52. An image processing method for determining information corresponding to image lightness in response to radiance-identifying information for a selected image field, said method having the improvement comprising the steps of
A. representing said radiance-identifying information for each of selected segmental areas of the viewing field, B. determining a selected comparison measure between said identifying information for each segmental area and said information for another segmental area, and determining therefrom and from a previously-determined lightness-identifying quantity for each latter segmental area a newly-determined lightness-identifying quantity for each former segmental area, C. effecting a selected multiple of said computations sequentially between segmental areas that correspond to differently-spaced locations in said field of view, and D. producing said lightness-information for said image field in response to said multiple determinations.
-
57. An image processing method for determining information corresponding to image lightness in response to radiance-identifying information for a selected image field, said method having the improvement comprising the steps of
A. representing said radiance-identifying information for each of selected segmental areas of the viewing field, B. determining a selected comparison measure between said identifying information for each segmental area and said information for another segmental area, and determining therefrom and from a previously-determined lightness-identifying quantity for each former segmental area a newly-determined lightness-identifying quantity for each latter segmental area, said measure-determination including means for effecting a determination of said measure for each of a selected plurality of areas prior to effecting a further such determination for an area of that plurality, C. effecting a selected multiple of said determinations for said plurality of areas sequentially, different ones of said sequential determinations being between segmental areas having a spatial parameter different from that of the areas of other such determinations, and applying each newly-determined quantity of one determination as a previously-determined quantity in a subsequent determination, and further including ordering said determinations according to the magnitude of said spatial parameter, and D. producing said lightness-information for said image field in response to said multiple determinations.
-
58. A lightness-imaging method in which information is provided identifying optical radiance associated with arrayed sections of a selected image field, said method further comprising the steps of
A. selectively grouping segmental areas of said image field a selected number of times, different ones of at least some of said groupings involving areas having at least one spatial parameter different from other groupings of areas, B. providing, for each grouping of segmental areas, at least one measure of visually significant transition in said radiance information between areas of that grouping, said measures being with reference to a selected lightness condition, and C. determining image lightness for each arrayed section of the image field in response to a plurality of said measures, at least some of which are provided for groupings which differ from one another in at least one spatial parameter selected from the parameters of distance, direction and size.
-
67. In a lightness-imaging method in which information is provided identifying optical radiance associated with each arrayed section of a selected image field, and including
(i) selectively pairing segmental areas of said image field a selected number of times, each said pairing being of segmental areas of identical configuration and size, (ii) providing, for each pairing of segmental areas, at least one comparative measure of said radiance information at the paired areas, and (iii) resetting each said measure with reference to a selected limit condition, the improvement comprising the further step of determining image lightness for each arrayed section of the image field in response to a plurality of said reset measures, at least some of which are provided for pairings which differ from one another in at least one spatial parameter.
-
74. A lightness-imaging method in which information is provided identifying optical radiance associated with arrayed sections of a selected image field, said method comprising the step of
A. pairing identically configured and sized segmental areas of said viewing field differently a number of times and for providing a multiple of sets of said different pairings, each said set involving areas of a size different from other sets, B. providing, for each pairing of segmental areas, a comparative measure of said radiance information at the paired areas, C. resetting each said measure with reference to a selected limit condition, and D. determining image lightness for each arrayed section of the image field in response to a plurality of said reset measures.
-
76. A lightness-imaging method in which information is provided identifying optical radiance associated with each arrayed section of a selected image field, said method comprising the steps of
A. selectively pairing segmental areas of said image field a selected number of times, each said pairing being of segmental areas of identical configuration and size, B. providing, for each pairing of segmental areas, at least one measure of transition in said radiance information between the paired areas, said measure conforming to the equation: -
space="preserve" listing-type="equation">log ip(xy)=log op(o,o)+log r(x,y)-log r(o,o)where log ip(x,y) is the log of the measure for a first segmental area at location (x,y) in the image field relative to a reference location for a second area paired therewith, log op(o,o) is the log of the measure previously assigned to or determined for said second segmental area at said reference location (o,o) in the image field and paired with said first area, and log r(x,y) and log r(o,o) are the logs of the radiance information for said first and second paired areas, respectively, C. resetting each said measure with reference to a selected limit, and D. determining image lightness for each arrayed section of the image field in response to an arithmetic averaging of a plurality of said reset measures, at least some of which are provided for pairings which differ from one another in at least one spatial parameter.
-
-
77. A lightness-imaging method in which information is provided identifying optical radiance associated with each arrayed section of a selected image field, said method comprising the steps of
A. selectively pairing segmental areas of said image field a selected number of times, each said pairing being of segmental areas of identical configuration and size, B. providing, for each pairing of segmental areas, at least one measure of transition in said radiance information between the paired areas, said measure conforming to the equation: -
space="preserve" listing-type="equation">log np(x,y)=1/2{[log op(x,y)]+[log op(o,o)+log r(x,y)-log r(o,o)]}where log np(x,y) is the log of the measure for a first segmental area at location (x,y) in the image field relative to a reference location for a second area paired therewith, log op(x,y) is the log of the measure previously assigned to or determined for said first area, log op(o,o) is the log of the measure previously assigned to or determined for said second segmental area at said reference location (o,o) in the image field and paired with said first area, and log r(x,y) and log r(o,o) are the logs of the radiance information for said first and second paired areas, respectively, and where each said term [log op (o,o)+log r(x,y)-log r(o,o)] is reset with reference to a selected limit. - View Dependent Claims (78)
-
-
79. Image processing apparatus comprising
A. means for receiving information responsive to the radiance values defining an image field, and B. means for deriving from said information a lightness field containing final lightness values for predetermined segmental areas of said image field, said final lightness value deriving means establishing initial lightness values for all areas of said image field and sequentially performing a selected number of process steps for said image field, in each step of which process selected areas of said image field are selectively paired with different areas of said image field and in successive steps of which process such pairings of areas differ from other pairings in at least one spatial parameter according to a predetermined sequence, and in each of which steps such paired areas are compared to establish a new lightness value for each said selected area as a function of the ratio of its radiance value to that of the different area with which it is paired and as a function of lightness values established for such paired areas in a preceding process step, and wherein said final lightness value for each said segmental area comprises an effective comparison of information responsive to its radiance value to information responsive to the radiance value from substantially all other areas of said image field without a direct comparison to each of said other segmental areas.
-
84. Image processing apparatus comprising
A. means for receiving information responsive to the radiance values defining an image field, and B. means for deriving from said information a lightness field containing final lightness values for predetermined segmental areas of said image field, said final lightness value deriving means establishing initial lightness values for all areas of said image field and performing a selected number of process steps for said image field, in each step of which process selected areas of said image field are selectively paired with different areas of said image field and in different steps of which process such pairings of areas differ selectively from other pairings in at least one spacial parameter, and in each of which steps such paired areas are compared to establish a new lightness value for each said selected area as a function of the ratio of its radiance value to that of the different area with which it is paired and as a function of lightness values established for such paired areas in a different process step, and in which said one spatial parameter is selected, for at least selected different ones of such pairings, to establish new lightness values for areas that are at least relatively small or relatively closely spaced apart using lightness values established for areas that are comparatively larger or comparatively further spaced apart, and wherein said final lightness value for each said segmental area comprises an effective comparison of information responsive to its radiance value to information responsive to the radiance value from substantially all other areas of said image field without a direct comparison to each of said other segmental areas.
-
85. An image processing method comprising the steps of
A. receiving information responsive to the radiance values defining an image field, and B. deriving from said information a lightness field containing final lightness values for predetermined segmental areas of said image field, said final lightness value deriving step establishing initial lightness values for all areas of said image field and sequentially performing a selected number of process steps for said image field, in each step of which process selected areas of said image field are selectively paired with different areas of said image field and in successive steps of which process such pairings of areas differ from other pairings in at least one spatial parameter according to a predetermined sequence, and in each of which steps such paired areas are compared to establish a new lightness value for each said selected area as a function of the ratio of its radiance value to that of the different area with which it is paired and as a function of lightness values established for such paired areas in a preceding process step, and wherein said final lightness value for each said segmental area comprises an effective comparison of information responsive to its radiance value to information responsive to the radiance value from substantially all other areas of said image field without a direct comparison to each of said other segmental areas.
-
86. An image processing method comprising the steps of
A. receiving information responsive to the radiance values defining an image field, and B. deriving from said information a lightness field containing final lightness values for predetermined segmental areas of said image field, said final lightness value deriving step establishing initial lightness values for all areas of said image field and performing a selected number of process steps for said image field, in each step of which process selected areas of said image field are selectively paired with different areas of said image field and in different steps of which process such pairings of areas differ selectively from other pairings in at least one spacial parameter, and in each of which steps such paired areas are compared to establish a new lightness value for each said selected area as a function of the ratio of its radiance value to that of the different area with which it is paired and as a function of lightness values established for such paired areas in a different process step, and in which said one spatial parameter is selected, for at least selected different ones of such pairings, to establish new lightness values for areas that are at least relatively small or relatively closely spaced apart using lightness values established for areas that are comparatively larger or comparatively further spaced apart, and wherein said final lightness value for each said segmental area comprises an effective comparison of information responsive to its radiance value to information responsive to the radiance value from substantially all other areas of said image field without a direct comparison to each of said other segmental areas.
Specification