JP6172998B2 - Image processing apparatus and image processing method - Google Patents

Description

  The present invention relates to an image processing apparatus and an image processing method for controlling an image processing system that forms a connected image obtained by connecting output images from a plurality of image output apparatuses.

  In recent years, technological development of a video projection system (hereinafter referred to as a multi-projection system) that displays a single image by connecting projection images projected from different projectors to different areas has been progressing. According to the multi-projection system, it is possible to display an image with a resolution exceeding the performance of each projector. However, due to differences in the performance of individual projectors and the geometric conditions such as the position of the projector relative to the screen, the color reproduction between projectors varies. Therefore, in the multi-projection system, it is necessary to perform a correction process for absorbing variations in reproduction colors between projectors for each projector.

  The following proposals have been made as a technique for such correction processing. First, there is a technique in which a target luminance is uniquely set in advance and a correction parameter for reproducing the target luminance value is calculated for each projector or pixel (see, for example, Patent Document 1). According to this technique, by converting and projecting an image based on the correction parameter, it is possible to make the luminance substantially constant in all regions projected from each projector (hereinafter, all projection regions). There is also a technique for changing the position of projectors so that projectors with similar characteristics are adjacent to each other (see, for example, Patent Document 2). According to this technology, it is possible to suppress variations between adjacent projectors by changing the arrangement position according to the characteristics of the projector.

JP 2002-116500 A JP 2000-059806 JP

  In the method described in Patent Document 1, it is necessary to set the target luminance value to the lowest luminance value in all the projection areas before correction in order to make the luminance value constant in all the projection areas. Therefore, after the correction, there is a problem that the luminance display is greatly reduced from the luminance that can be displayed by the projector. In the method described in Patent Document 2, it is necessary to perform geometric correction such as alignment every time the arrangement position of the projector is changed. In addition, when the variation in the color reproduction between projectors is caused by geometric conditions such as the angle change characteristic of the screen, it cannot be handled by changing the arrangement position.

  In view of the above problems, the present invention provides an image processing system that forms a connected image obtained by connecting output images from a plurality of image output devices, and performs color reproduction between adjacent devices while suppressing restrictions on the color gamut that each device can reproduce. It aims at suppressing the dispersion | variation of.

In order to achieve the above object, an image processing apparatus of the present invention comprises the following arrangement. That is,
An image processing device that controls an image processing system that forms a connected image obtained by connecting output images from a plurality of image output devices,
Characteristic acquisition means for acquiring the respective color reproduction characteristics of the plurality of image output devices;
Correction order setting means for setting a correction order for the plurality of image output devices based on a positional relationship between a reference position in the connected image and each output image;
Correction means for correcting the color reproduction characteristics of the image output device according to the correction order set by the correction order setting means,
The correction unit corrects the color reproduction characteristics of the target image output device to be corrected, and reproduces the color of the adjacent image output device that outputs an output image adjacent to the output image of the target image output device. Based on the characteristics, correct the color reproduction characteristics of the image output device of interest ,
The correction means sets a target color for correction based on the color reproduction characteristic of the adjacent image output apparatus for the target image output apparatus, and uses the target color for the color reproduction characteristic of the target image output apparatus. Correct,
The correction order setting means sets a plurality of image output devices for one correction order,
When the leading correction order is set in the attention image output device, the correction unit is configured to perform the correction for the attention image output device based on the color reproduction characteristics of the image output device in which the leading correction order is set. A target color is set .

  According to the present invention, in an image processing system for forming a connected image obtained by connecting output images from a plurality of image output devices, variation in color reproduction between adjacent devices while suppressing restrictions on a color gamut that can be reproduced by each device. Can be suppressed.

A block diagram showing a hardware configuration of a multi-projection system according to the first embodiment, A block diagram showing a functional configuration of a system in the first embodiment, The figure which shows the example of a correction data format in 1st Embodiment, A flowchart showing a projection process in the first embodiment, The figure which shows the structural example of all the projection areas in 1st Embodiment, The figure which shows the example of UI in 1st Embodiment, The figure which shows the structural example of the color chart image used in 1st Embodiment, The figure which shows the data format example of the color reproduction characteristic of the projector in 1st Embodiment, A flowchart showing correction data generation processing in the first embodiment, The figure for demonstrating the correction order in 2nd Embodiment, The figure which shows the example of UI in 2nd Embodiment, The figure for demonstrating the correction order in 3rd Embodiment, The figure which shows the structural example of all the projection areas in 4th Embodiment, A flowchart showing a correction order setting process in the fourth embodiment, The figure which shows the example of UI in 5th Embodiment, FIG. 10 is a diagram showing an example of a data format of a file that instructs a correction order in the fifth embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following embodiments do not limit the present invention related to the scope of claims, and all combinations of features described in the present embodiments are essential to the solution means of the present invention. Not exclusively.

<First Embodiment>
Device Configuration The hardware configuration of the multi-projection system in this embodiment will be described with reference to FIG. In the figure, a CPU 101 executes a program stored in a storage device such as an HDD 103 using a RAM 102 as a work memory, and controls each component connected via a main bus 109. An input interface (I / F) 104 connects an input device 106 such as a mouse and a keyboard and a measuring device 107 that measures characteristics such as a projector to the main bus 109. The output I / F 105 connects the projector group 108 and the like to the main bus 109. In the present embodiment, a multi-projection system including 16 projectors will be described as an example. However, the number of projectors is not limited to this, and the present invention can be applied to any multi-projection system including a plurality of projectors.

  FIG. 2 shows a logical configuration of functions in the multi-projection system 2 of the present embodiment. The information processing apparatus 200 includes a correction order setting unit 201, a correction data generation unit 202, an image correction unit 203, an input data acquisition unit 204, an image output control unit 205, a storage unit 206, and a measurement device control unit 207.

  The correction order setting unit 201 sets the order in which correction processing is performed on a plurality of projectors. The correction data generation unit 202 calculates correction data for reproducing a target color for each target projector. Here, the correction data is an RGB value (hereinafter referred to as an output RGB value) that is output when a target color corresponding to a certain RGB value (hereinafter referred to as an input RGB value) is reproduced by a target projector. As shown in FIG. 3, the correction data generation unit 202 has a correspondence table of input RGB values and output RGB values (hereinafter, RGB-RGBLUT). The image correction unit 203 reads the image stored in the storage unit 206, and updates each RGB value to be output for each target projector according to each correction data. The input data acquisition unit 204 acquires information such as the arrangement configuration of the projector from the instruction input unit 208. The measuring device control unit 207 controls the measuring device 209 to acquire the color reproduction characteristics of each projector. As the color reproduction characteristics of the projector acquired by the measuring apparatus 209, for example, CIE tristimulus values XYZ values of a total of 729 color charts are acquired for each of 9 steps of RGB. The image output control unit 205 reads the image stored in the storage unit 206 and controls the projector 210 to project the image onto the screen 211.

Projection Processing Hereinafter, projection processing in the multi-projection system 2 of the present embodiment will be described using the flowchart of FIG.

  First, in S 1, the input data acquisition unit 204 acquires information on the arrangement configuration of the projector and stores it in the storage unit 206. Here, FIG. 5 shows a configuration example of the entire projection area in the present embodiment. In FIG. 5, each of the areas 1 to 16 represents the projection area of each of the 16 projectors. In the following description, it is assumed that the projections on the regions 1 to 16 are performed by the projectors 1 to 16, respectively. The information related to the arrangement configuration acquired in S1 is the number of projectors and the positional relationship (number of columns in the vertical and horizontal directions) of the projection area as shown in FIG. Input by instruction. Specifically, the image output control unit 205 controls the projector 210 to project a UI as shown in FIG. 6, and the user inputs each parameter according to the projection. In FIG. 6, 1001 is an input area for the number of projectors, and 1002 is an input area for the number of rows and columns. When the display button 1003 is pressed after these inputs, the arrangement configuration is automatically displayed in the window 1005. When the user confirms the arrangement configuration to be displayed and presses the save button 1004, information regarding the arrangement configuration is acquired.

  Next, in S2, the measurement apparatus control unit 207 initializes the number i for identifying the projectors 1 to 16 to 1 and stores it in the storage unit 206. In step S3, the image output control unit 205 controls the projector 210 to project a color chart image (hereinafter, chart image) onto the screen 211. FIG. 7 shows a configuration example of the projected chart image. The rectangular area shown in FIG. 7 is composed of color charts of 9 steps for each of RGB and 729 colors in total, and the chart image is stored in the storage unit 206 in advance. In step S4, the measurement device control unit 207 controls the measurement device 209 to measure the chart image projected by the i-th projector, and acquires the color reproduction characteristics of the projector. Here, the measuring device 209 is a two-dimensional measuring instrument, and can acquire color reproduction characteristics for all color charts in the chart image shown in FIG. 7 by one measurement. The projector color reproduction characteristics acquired here are stored in the storage unit 206. FIG. 8 shows a data format example of color reproduction characteristics. As shown in FIG. 8, the color reproduction characteristics acquired in S4 are CIE tristimulus XYZ values corresponding to color charts of 729 colors in 9 steps for each of RGB. In S5, the measurement device control unit 207 determines whether or not the color reproduction characteristic acquisition processing in S3 to S4 has been executed for all projectors. If there is a projector that has not been executed, the process proceeds to S6. If it has been executed, the process proceeds to S7. Here, all projectors indicate 16 projectors (N = 16), and the end of processing for all projectors is determined by comparison with the value of i held in the storage unit 206. In S6, the measurement device control unit 207 increments the value of i and stores it in the storage unit 206.

  As described above, the color reproduction characteristics for all projectors are acquired by the processing of S1 to S6, and then the image correction processing for each projector is performed.

  First, in step S7, the correction order setting unit 201 sets the correction order of the projector and stores it in the storage unit 206. FIG. 5 shows an example of setting the projector correction order. With the center of all the projection areas as the reference position C, the correction rank numbering is automatically performed in the order of the projectors corresponding to the projection areas with a short distance from the reference position C. In the example of FIG. 5, first, the projectors 6, 7, 10, 11 close to the reference position C are in the first correction order. The projectors 2, 3, 5, 9, 8, 12, 14, and 15 are the second correction order, and the projectors 1, 4, 13, and 16 are the third correction order.

  Next, in S8, the image output control unit 205 initializes the number j for identifying the correction order (first to third) of the projector to 1, and stores it in the storage unit 206. In step S9, the correction data generation unit 202 generates correction data for the projector having the correction rank j and stores the correction data in the storage unit 206. Here, the correction data is RGB-RGBLUT as shown in FIG. The details of the correction data generation process will be described later.

  In S10, the image correction unit 203 reads the correction data of each projector generated in S9 from the storage unit 206, and corrects each image based on the correction data. It is assumed that the corrected image is stored in the storage unit 206. Image correction is performed for each projector. First, an RGB value of an image is read and used as an input RGB value, and then an output RGB value corresponding to the input RGB value is searched with reference to the RGB-RGBLUT generated in S9. However, as described above, since RGB-RGBLUT is an input / output correspondence table for 729 colors, output RGB values corresponding to input RGB values not included in the 729 colors are output RGB values by interpolation operations such as tetrahedral interpolation. Is calculated. Finally, the RGB value of the image is replaced with the output RGB value.

  In step S11, the image output control unit 205 reads the image corrected in step S10 from the storage unit 206, and controls the projector 210 to project the corrected image onto the screen 211. Then, in S12, the image output control unit 205 determines whether or not the projection processing in S9 to S11 has been executed for all the orders in the correction order determined in S7. If there is an unprocessed order, the process proceeds to S13. If all have been executed, the process ends. Here, all correction orders indicate values of 1 to 3 (M = 3), and the end of processing for all correction orders is determined by comparison with the value of j held in the storage unit 206. In S13, the image output control unit 205 increments the value of j and stores it in the storage unit 206.

  As described above, the image correction processing for all projectors is completed by the processing of S7 to S13.

Correction data generation process (S9)
Hereinafter, the correction data generation processing in S9 will be described in detail with reference to the flowchart of FIG.

  The correction data generation unit 202 uses the reproduction color of the adjacent projector as the target color, and sequentially generates correction data according to the correction order determined in S7. S9 is a process performed for the projector having the correction order j. When there are a plurality of projectors corresponding to the correction order j, each process described below is applied to the plurality of projectors simultaneously.

  First, in S901, an adjacent projector is set for the projector corresponding to the correction order j. Here, the adjacent projector refers to a projector that has performed projection onto any one of the upper, lower, left, and right areas of the projection area of the target projector and has already performed the correction data generation process in S9. Specifically, for the projector corresponding to each projection area shown in FIG. 5, the projector that projects onto the area ahead of the arrow in that area is the adjacent projector. For example, for the projector 13, the projector 9 and the projector 14 are adjacent projectors. Note that the projectors 6, 7, 10, and 11 with the correction order j = 1 are set such that there is no adjacent projector because there is no projector for which S9 has already been executed.

  In step S902, for each projector corresponding to the correction order j, the color reproduction characteristics of the adjacent projector are read from the storage unit 206, and a target color is set. Here, the color reproduction characteristic of the adjacent projector refers to the color reproduction characteristic after correction in S905 described later, not the color reproduction characteristic before correction measured using the measurement device 209 in S4. As described above, there is no corrected adjacent projector for the projectors 6, 7, 10, and 11 in the correction order (j = 1) to be processed first. Therefore, for the projector having the top correction order, the average value of the color reproduction characteristics (XYZ values) of these projectors is set as the target color. When there are a plurality of corrected adjacent projectors such as the projector 13, the average value of the color reproduction characteristics (XYZ values) of these adjacent projectors is set as the target color.

  In S903, the color reproduction characteristics before correction of each projector corresponding to the correction order j, that is, the color reproduction characteristics of the projector acquired in S4 are read from the storage unit 206.

  In S904, correction data (RGB-RGBLUT) is generated from the target color set in S902 and the color reproduction characteristics before correction read in S903. First, the XYZ value before correction of the projector and the XYZ value of the target color corresponding to the 729 color RGB values are all converted to CIELAB. Thereby, a correspondence relationship between the input RGB value and the LAB value before correction is obtained. Next, an RGB value (output RGB value) for reproducing the LAB value (target LAB value) that is the target color is calculated based on the correspondence relationship between the input RGB value and the LAB value before correction. However, since the correspondence between the input RGB value and the LAB value before correction is stored only for 729 colors, the output RGB value is calculated by interpolation such as tetrahedral interpolation for the target LAB value not included in the 729 color It shall be. Further, when the target LAB value is out of the color gamut of the projector i, an output RGB value that reproduces the LAB value in the color gamut closest to the target LAB value (minimum color difference) is calculated. Thus, correction data (RGB-RGBLUT) that associates the input RGB value with the output RGB value is created.

  In step S905, the color reproduction characteristics after correction are stored in the storage unit 206 for each projector corresponding to the correction order j. Here, the color reproduction characteristics after correction are XYZ values reproduced with the output RGB values calculated in S904, and interpolation using the RGB value and XYZ value correspondence table showing the color reproduction characteristics before correction in FIG. This is a theoretical value obtained by calculating the XYZ values that the output RGB values reproduce by calculation.

  As described above, the present embodiment includes the following configuration in order to control an image processing system (specifically, a multi-projection system) that forms a connected image obtained by connecting output images from a plurality of image output devices. That is, first, the color reproduction characteristics of each of the plurality of image output devices are acquired (S1 to S6 in FIG. 4). Then, based on the positional relationship between the reference position in the connected image and each output image, a correction order for a plurality of image output devices is set (S7). Then, the color reproduction characteristics of the image output device are corrected according to the set correction order (S8 to S13). At the time of this correction, the color of the adjacent image output device that outputs the output image adjacent to the output image of the target image output device that has already been corrected for the color reproduction characteristics for the target image output device to be corrected Based on the reproduction characteristics, the color reproduction characteristics of the target image output device are corrected.

  According to this embodiment, color correction is performed sequentially from the center position of all the projection areas toward the outside based on the color reproduction characteristics of adjacent projectors that have been corrected. This makes it possible to suppress variations in color reproduction between adjacent projectors while suppressing restrictions on the color gamut that can be displayed by each projector.

<Second Embodiment>
Hereinafter, a second embodiment according to the present invention will be described. In the first embodiment described above, an example in which correction processing of each projector is performed in the order of propagation from the center of all the projection areas toward the outside has been described. In the second embodiment, an example is shown in which an arbitrary point is set as a reference position, and correction processing of each corresponding projector is performed in the order of propagation from the reference position toward the outside projection area. Note that the configuration of the multi-projection system in the second embodiment is the same as that in the first embodiment, and a description thereof will be omitted. Also, the projection processing in the multi-projection system of the second embodiment follows the flowchart of FIG. 4 shown in the first embodiment.

Correction order setting process (S7)
Hereinafter, the correction order setting process in the second embodiment corresponding to S7 in FIG. 4 will be described with reference to FIG. As described above, in the second embodiment, the correction order is set after arbitrarily setting the reference position. Since processes other than S7 are the same as those in the first embodiment, description thereof will be omitted.

  The multi-projection system of the second embodiment is assumed to be composed of a total of nine projectors, that is, projectors 1 to 9 corresponding to the projection areas 1 to 9 as shown in FIG. In addition, regarding the distance between the projection areas, the distance between the upper, lower, left and right adjacent areas is 1. Further, the distance between the projection areas having the positional relationship in the oblique direction, such as the projection area 1 and the projection area 5 in the figure, is set to 2.

  First, as shown in FIG. 10 (a), the user sets the reference position A via the instruction input unit 208. This reference position A is designated by the UI shown in FIG. Specifically, a projection area number as a reference position is input to the reference position input area 1006 in FIG. In FIG. 11, the other input areas, buttons, and windows (1001 to 1005) are the same as the UI shown in FIG. 6 in the first embodiment. In the example of FIG. 10 (a), the projection area 8 by the projector 8 is set as the reference position. Note that the projector 8 corresponding to the reference position does not perform image correction since there is no target adjacent projector.

  Next, as shown in FIG. 10 (b), for the projectors 5, 7, and 9 corresponding to the projection area whose distance from the reference position is 1, the projector 8 corresponding to the projection area 8 that is the arrow destination in each figure. Is corrected using as an adjacent projector. That is, the target color is calculated from the color reproduction characteristics of the projector 8, and the same color correction as that in the first embodiment is performed.

  Further, as shown in FIG. 10 (c), for the projectors 2, 4, and 6 corresponding to the projection area whose distance from the reference position is 2, the corrected projector 2 corresponding to the projection area that is the arrow destination in each figure Is used as an adjacent projector.

  Finally, as shown in FIG. 10 (d), with respect to the projectors 1 and 3 corresponding to the projection area whose distance from the reference position is 3, the corrected projector corresponding to the projection area that is the arrow destination in each figure is displayed. Correction is performed as an adjacent projector.

  Here, an example is shown in which the reference position is arbitrarily set by the user. However, for example, by using a sensor that detects the user's position, the projector corresponding to the projection area closest to the user is automatically set as the reference position. Is also possible.

  As described above, according to the second embodiment, by setting an arbitrary reference position, it is possible to set a correction order according to the purpose such as priority of the viewpoint position of the user.

<Third embodiment>
The third embodiment according to the present invention will be described below. In the first and second embodiments described above, an example in which one reference position is set in all projection areas has been described. The third embodiment shows an example in which a plurality of reference positions are set. Note that the configuration of the multi-projection system in the third embodiment is the same as that in the first embodiment, and a description thereof will be omitted. Further, the projection processing in the multi-projection system of the third embodiment also follows the flowchart of FIG. 4 shown in the first embodiment.

Correction order setting process (S7)
Hereinafter, the correction order setting process in the third embodiment corresponding to S7 in FIG. 4 will be described with reference to FIG. As described above, in the third embodiment, the correction order is set after setting a plurality of reference positions. Since processes other than S7 are the same as those in the first embodiment, description thereof will be omitted.

  The multi-projection system of the third embodiment is assumed to be composed of a total of five projectors, projectors 1 to 5 corresponding to the projection areas 1 to 5 as shown in FIG. As for the distance between the projection areas, the distance between the adjacent areas on the left and right is 1.

  First, as shown in FIG. 12A, the user sets the reference positions A and B via the instruction input unit 208. In this example, projection areas 1 and 5 by projectors 1 and 5 are set as reference positions. Note that the projectors 1 and 5 corresponding to the reference position do not perform image correction because there is no target adjacent projector.

  Next, as shown in FIG. 12 (b), for the projectors 2 and 4 corresponding to the projection areas whose distance from the reference position is 1, the projectors 1 corresponding to the projection areas 1 and 5 that are the arrow destinations in the drawings. , 5 is corrected as an adjacent projector. That is, for example, for each of the projectors 2 and 4, a target color is calculated from the color reproduction characteristics of the projectors 1 and 5, and color correction similar to that in the first embodiment is performed.

  Finally, as shown in FIG. 12 (c), for the projector 3 corresponding to the projection area whose distance from the reference position is 2, the corrected projectors 2 and 4 corresponding to the projection area indicated by the arrow in FIG. Correction is performed as a projector.

  As described above, according to the third embodiment, by setting a plurality of arbitrary reference positions, it is possible to set a correction order according to various purposes, such as when giving priority to the viewpoint positions of a plurality of users. it can.

  In the first to third embodiments, an example has been described in which the distance between the upper, lower, left, and right projectors is 1, and the projector of the distance 1 is an adjacent projector. However, as a distance calculation method, for example, the Euclidean distance is used. Different methods may be applied.

<Fourth embodiment>
The fourth embodiment according to the present invention will be described below. For example, in the first embodiment described above, the example in which the correction order is set so as to propagate from the center of all the projection areas toward the outside has been described. In the fourth embodiment, a predicted result and an evaluation value are calculated when correction is applied according to a plurality of correction orders for luminance reduction after correction and luminance variations between projectors, and an optimal correction order is calculated based on the evaluation values. An example of setting Note that the configuration of the multi-projection system in the fourth embodiment is the same as that of the first embodiment, but is configured by a total of five projectors, that is, the projectors 1 to 5 corresponding to the projection areas 1 to 5 as shown in FIG. Let's say. The projection processing in the multi-projection system of the fourth embodiment also follows the flowchart of FIG. 4 shown in the first embodiment.

Correction order setting process (S7)
Hereinafter, the correction order setting process in the fourth embodiment corresponding to S7 in FIG. 4 will be described with reference to the flowchart in FIG. As described above, in the fourth embodiment, the correction order is set based on the predicted evaluation value after correction. Since processes other than S7 are the same as those in the first embodiment, description thereof will be omitted.

  As shown in FIG. 14, the correction order setting unit 201 first performs an initial setting of ordering for all the projectors 1 to 5 in S701, and stores the set order in the storage unit 206. Here, it is assumed that the order of projectors 1, 2, 3, 4, and 5 is initially set. In step S702, the number j for identifying the projector correction order (1 to M, M = 5) is initialized to 1 and stored in the storage unit 206. In step S703, correction data is generated for the projector corresponding to the correction order j. Since this correction data generation process is the same as S9 in FIG. 4, the description thereof is omitted here. Through the processing, the projector correction data corresponding to the correction order j and the corrected color reproduction characteristics are stored in the storage unit 206. In step S704, it is determined whether the correction data generation processing in step S703 has been executed for all correction orders (1 to M). If there is an unprocessed correction order, the value of j is incremented and stored in the storage unit 206 in S705, and if all have been executed, the process proceeds to S706.

  In S706, the corrected color reproduction characteristics of each projector are read from the storage unit 206, the evaluation value P when the correction processing is executed in the correction order is calculated according to the following evaluation formula (1), and stored in the storage unit 206. To do.

P = 1 / (k1 / ΣdL + k2 / ΣdS) (1)
ΣdL in equation (1) represents the sum of the differences in white luminance between adjacent projectors after correction. That is, for all projectors 1 to 5, the sum of the brightness difference between projectors 1 and 2, the brightness difference between projectors 2 and 3, the brightness difference between projectors 3 and 4, and the brightness difference between projectors 4 and 5 is indicated. . It is shown that the smaller the value of ΣdL, the smaller the variation between adjacent projectors after correction.

  In addition, ΣdS in Expression (1) indicates the total sum of the differences in white luminance before and after correction of each projector. That is, for all projectors 1 to 5, for each projector 1 to 5, the luminance difference between the uncorrected white luminance and the corrected white luminance was calculated, and the sum of the luminance differences for the five projectors was obtained. Is. It is indicated that the smaller the value of Σds is, the smaller the luminance drop (limit) due to the correction process is.

  Further, k1 and k2 in the expression (1) indicate constant values designated by the user via the instruction input unit 208. Therefore, the user can adjust which of ΣdL and Σds is prioritized by adjusting the constants k1 and k2. In other words, the evaluation value P is controlled by weighting which is prioritized with respect to the degree of suppression of variation in brightness between output images by adjacent projectors and the degree of maintenance of the sum of brightness (contrast) in the output images of all projectors. Is possible. Therefore, the evaluation value P according to the purpose can be calculated.

  In step S707, it is determined whether evaluation values have been calculated for all correction orders. For example, the multi-projection system of the present embodiment includes five projectors. If these are sequentially corrected one by one, a total of 120 correction orders can be set for the five projectors. Therefore, in S707, it is determined whether or not evaluation values have been calculated for all 120 correction orders. If there is an unprocessed correction order, the process proceeds to S708, the correction order to be processed is changed to a correction order for which evaluation value calculation has not been performed and stored in the storage unit 206, and then the process returns to S702. On the other hand, if evaluation value calculation has been performed for all correction orders, the process proceeds to S709, the evaluation values corresponding to each correction order are read from the storage unit 206, and the correction order that maximizes the evaluation value is set in the storage unit 206. To do.

  In the fourth embodiment, the processes after S7 in FIG. 4 are performed according to the correction order set as described above.

  As described above, according to the fourth embodiment, evaluation values for a plurality of correction orders in a plurality of projectors are provided, and an optimal correction order is set according to the evaluation values. Accordingly, it is possible to perform a correction process in which the user arbitrarily sets, according to the purpose, whether to give priority to the reduction of the color gamut that can be displayed by the projector or the variation between adjacent projectors.

  Although the evaluation value is defined by the evaluation formula (1) in the fourth embodiment, the evaluation value is not limited to this example, for example, an evaluation value that considers not only the luminance but also a difference in color gamut volume before and after the correction. May be used.

<Fifth embodiment>
Hereinafter, a fifth embodiment according to the present invention will be described. In the first to fourth embodiments described above, the example in which the correction order of the projector is automatically set according to the reference position, the evaluation value, and the like has been described. However, in the fifth embodiment, the correction order can be set by the user. Show. As in the first embodiment, the multi-projection system in the fifth embodiment includes a total of 16 projectors, that is, projectors 1 to 16 corresponding to the projection areas 1 to 16 as shown in FIG. To do. The projection processing in the multi-projection system of the fifth embodiment also follows the flowchart of FIG. 4 shown in the first embodiment.

Correction order setting process (S7)
Hereinafter, the correction order setting process in the fifth embodiment corresponding to S7 in FIG. 4 will be described with reference to FIG. FIG. 15 shows an example of a UI that is projected by the image output control unit 205 controlling the projector 210 in S7. Since processes other than S7 are the same as those in the first embodiment, description thereof will be omitted.

  In FIG. 15, when a reference button 1007 is pressed, a file instructing the correction order is selected in the data format as shown in FIG. By creating the file in advance by the user, it is possible to arbitrarily set all the orders 1 to N for the N projectors. The other input areas and buttons 1001 to 1005 in FIG. 15 are the same as the UI shown in FIG. 6 in the first embodiment, and thus the description thereof is omitted.

  In the fifth embodiment, the processes after S7 in FIG. 4 are performed according to the correction order described in the file selected by the UI.

  As described above, according to the fifth embodiment, it is possible to perform correction processing in an arbitrary correction order by inputting a correction order preset by the user.

<Other embodiments>
Hereinafter, other embodiments of the present invention will be described.

  In each of the above-described embodiments, an example in which the color reproduction characteristics of the projector before correction are acquired using the measurement device 209 in the multi-projection system 2 has been described, but the method for acquiring the color reproduction characteristics is not limited to this example. For example, instead of the measuring device 209, a photographing device such as a digital camera may be provided, and the measurement XYZ may be obtained by converting RGB values obtained by photographing each color chart in the chart image. Any one of the following formulas (2), (3), and (4) can be used for the conversion from the captured RGB value to the measured XYZ value. In each equation, Rp, Gp, and Bp represent the captured RGB values, and Xp, Yp, and Zp represent the measured XYZ values.

｜ Xp ｜ ｜ Rp ｜
| Yp | = M1 ・ | Gp | (2)
｜ Zp ｜ ｜ Bp ｜

｜ Rp ｜
｜ Gp ｜
｜ Xp ｜ ｜ Bp ｜
| Yp | = M2 ・ | Rp ・ Rp | (3)
｜ Zp ｜ ｜ Gp ・ Gp ｜
｜ Bp ・ Bp ｜
｜ 1 ｜
M1 and M2 in the equations (2) and (3) respectively indicate 3 × 3 and 3 × 7 matrices for converting photographed values to colorimetric values, and the matrices are stored in advance in the storage unit 206 and the like. It shall be. The order of the matrix is not limited to the above two types, and may be a matrix of 3 × 10, for example.

  In addition, the multi-projection system may not include a measurement device or an imaging device, and a measurement value measured in advance or obtained by conversion from an imaging value may be stored in the storage unit 206 and read out.

  In each of the above-described embodiments, an example in which a theoretical value by interpolation calculation is used for the color reproduction characteristics of the projector after correction has been shown. However, after correction, the actual measurement value is obtained by projecting and measuring the chart image again. May be.

  In each of the above embodiments, the color reproduction characteristics of the projector have been described as XYZ values for 9 steps of 729 RGB colors, but the color reproduction characteristics are not limited to this example. For example, CIELAB or the like obtained by converting the XYZ values may be used, and the number of colors may be 125 colors of RGB 5 steps or 49 colors of RGB 17 steps.

  Further, the present invention provides a storage medium storing a program code of software for realizing the functions of the above-described embodiments (for example, processing shown by a flowchart in which processing of each unit described above is associated with each process), a system or an apparatus It can also be realized by supplying to. In this case, the function of the above-described embodiment is realized by the computer (or CPU or MPU) of the system or apparatus reading and executing the program code stored in the storage medium so that the computer can read it.

Claims (10)

An image processing device that controls an image processing system that forms a connected image obtained by connecting output images from a plurality of image output devices,
Characteristic acquisition means for acquiring the respective color reproduction characteristics of the plurality of image output devices;
Correction order setting means for setting a correction order for the plurality of image output devices based on a positional relationship between a reference position in the connected image and each output image;
Correction means for correcting the color reproduction characteristics of the image output device according to the correction order set by the correction order setting means,
The correction unit corrects the color reproduction characteristics of the target image output device to be corrected, and reproduces the color of the adjacent image output device that outputs an output image adjacent to the output image of the target image output device. Based on the characteristics, correct the color reproduction characteristics of the image output device of interest ,
The correction means sets a target color for correction based on the color reproduction characteristic of the adjacent image output apparatus for the target image output apparatus, and uses the target color for the color reproduction characteristic of the target image output apparatus. Correct,
The correction order setting means sets a plurality of image output devices for one correction order,
When the leading correction order is set in the attention image output device, the correction unit is configured to perform the correction for the attention image output device based on the color reproduction characteristics of the image output device in which the leading correction order is set. An image processing apparatus characterized by setting a target color . 2. The image processing apparatus according to claim 1 , wherein the reference position is set according to a user instruction. 3. The image processing apparatus according to claim 1, wherein the reference position is set at a plurality of positions in the connected image. 2. The image processing apparatus according to claim 1 , wherein the reference position is set at a center of the connected image. The correction order setting means calculates evaluation values of color reproduction characteristics for all image output devices after correction by the correction means for all correction orders that can be set for the plurality of image output devices, and the image processing apparatus according to any one of claims 1 to 4, characterized in that setting the correction order in which the values is the highest. The evaluation value is a value that evaluates at least one of the degree of suppression of luminance variation between output images of adjacent image output devices and the degree of maintenance of total luminance in output images of all image output devices. 6. The image processing apparatus according to claim 5 , wherein the image processing apparatus is provided. The correction order setting means, the image processing apparatus according to any one of claims 1 to 4, characterized in that to set the correction order in response to a user instruction. The image processing apparatus according to any one of claims 1 to 7, wherein the image output device is a projector. An image processing method in an image processing apparatus for controlling an image processing system that forms a connected image obtained by connecting output images from a plurality of image output apparatuses, having characteristic acquisition means, correction order setting means, and correction means,
The characteristic acquisition means acquires the color reproduction characteristics of each of the plurality of image output devices;
The correction order setting means sets a correction order for the plurality of image output devices based on a positional relationship between a reference position in the connected image and each output image;
When the correction means corrects the color reproduction characteristics of the image output apparatus according to the set correction order, the color reproduction characteristics have already been corrected for the target image output apparatus to be corrected, and Based on the color reproduction characteristics of the adjacent image output apparatus that outputs an output image adjacent to the output image of the image output apparatus, the color reproduction characteristics of the target image output apparatus are corrected ,
The correction means sets a target color for correction based on the color reproduction characteristic of the adjacent image output device for the target image output device, and uses the target color as the color reproduction characteristic of the target image output device. Correct,
The correction order setting means sets a plurality of image output devices for one correction order,
When the correction means has a leading correction order set in the attention image output apparatus, the correction means is configured to perform the correction for the attention image output apparatus based on the color reproduction characteristics of the image output apparatus in which the leading correction order is set. An image processing method characterized by setting a target color . By being executed by a computer device, a program to function as each unit of the image processing apparatus according to the computer device in any one of claims 1 to 8.

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