JP2005150779A - Method for calculating display characteristics correction data of image display apparatus, display characteristic correction data program, and apparatus for calculating display characteristics correction data - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for calculating display characteristics correction data for an image display apparatus, capable of calculating correct correction data at all times, even when abnormality data are captured as photographing data due to changes in the external light or blocking-off of photographing by an obstacle in the case of photographing a test pattern. <P>SOLUTION: In the case that the image display apparatus sequentially displays a test pattern, on the basis of test pattern data, a plurality of photographing data are acquired by photographing the sequential test patterns and correction data to correct the display characteristic of the image display apparatus are calculated on the basis of a plurality of the acquired photographing data; analyzing a plurality of the acquired photographing data detects the presence / absence of abnormality photographing data, if the abnormality photographing data are detected, the photographing data corresponding to the test pattern data, when the abnormality photographing data are acquired again; and correction data to correct the display characteristic of the image display apparatus are calculated, on the basis of a plurality of the photographing data including the photographing data acquired again. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a display characteristic correction data calculation method for calculating correction data for display characteristics of an image display device based on photographing data obtained by displaying a test pattern on the image display device and photographing the test pattern, and calculation thereof The present invention relates to a program and a calculation device.

  Some image display devices are configured by only one video device, and some are configured by combining a plurality of video devices to achieve a larger screen. As an image display device formed by combining the plurality of video devices, for example, a plurality of projectors are used, and one large screen is formed on one screen by projecting a partial image from each projector. Multi-projection systems are known.

  In such an image display device, image distortion, image position deviation, color unevenness, luminance unevenness, white balance shift, non-optimal gamma characteristics, etc. may occur in each video device, and In a combination of video apparatuses, geometrical deviation, color deviation, luminance deviation, gamma characteristic difference, and the like may occur. If there is non-uniformity in display characteristics such as geometric characteristics, color characteristics, luminance characteristics, white balance characteristics, gamma characteristics, etc., there is a concern that this may be visually recognized and impair the quality of the entire image. .

  In order to deal with these points, a test pattern is displayed on the image display device, the image is photographed by a photographing device such as a digital camera, and correction data for correcting display characteristics based on the photographed image is obtained. There has been proposed a system that displays a high-quality video by creating and correcting display characteristics of the image display device based on the correction data.

  However, in this conventionally proposed system, when a display screen is photographed by a photographing device such as a digital camera in order to create correction data, as shown in FIG. 12, other than the test pattern from the video device is displayed on the display screen. For example, when external light is applied to a region indicated by a dotted line, correct correction data cannot be obtained. The external light in this case corresponds to, for example, illumination light when the video apparatus is disposed indoors, and corresponds to sunlight, moonlight, outdoor illumination, or the like when disposed outdoors.

As a method for solving such a problem of external light, for example, as shown in FIG. 13A, photographing data in a state where a test pattern is not displayed by the video apparatus, that is, a state where only external light is irradiated is obtained. By subtracting the photographic data from the photographic data when the test pattern and the external light shown in FIG. 12 are irradiated, the photographic data from which the influence of the external light as shown in FIG. 13B is removed is obtained. A method is known (see, for example, Patent Document 1).
JP-A-9-84036

  However, outside light incident on the display screen may be incident incidentally only at the time of photographing the test pattern, in addition to the case where it is incident on a regular basis. For example, if you are indoors, the light will be turned on while shooting the test pattern, and if you are outdoors, the light from the running vehicle may be incident while shooting the test pattern. There is. In such a case, it cannot be solved simply by subtracting the shooting data when nothing is emitted from the video apparatus from the shooting data of the test pattern.

  The same problem occurs when shooting is interrupted on the way, such as when a person passes in front of the camera as well as outside light.

  For this reason, in practice, when shooting a test pattern for obtaining correction data, a method of blocking outside light by a dark curtain or the like is often used.

  However, installing a black curtain has the problem of cost and time, and if the display screen is huge, such as a screen that replaces an electronic bulletin board in a stadium, it will be difficult to install the black curtain. There is a problem to say.

  Therefore, the object of the present invention made in view of such circumstances is that abnormal light is captured in the photographing data because the external light changes while photographing the test pattern or the photographing is blocked by an obstacle. Even in such a case, the object is to provide a display characteristic correction data calculation method for an image display device, a calculation program thereof, and a calculation device that can always calculate correct correction data and can display a high-quality image easily at low cost. .

The invention according to claim 1, which achieves the above object, sequentially displays test patterns on an image display device based on the test pattern data, captures the sequential test patterns, acquires a plurality of imaging data, and acquires the acquired data. A display characteristic correction data calculation method for an image display device that calculates correction data for correcting display characteristics of the image display device based on a plurality of shooting data,
An imaging data analysis process for analyzing the plurality of acquired imaging data and detecting the presence or absence of abnormal imaging data;
When abnormal shooting data is detected in the shooting data analysis step, a shooting data re-acquisition step for re-acquisition of shooting data corresponding to the test pattern data when the abnormal shooting data is acquired,
When abnormal shooting data is detected in the shooting data analysis step, to correct display characteristics of the image display device based on a plurality of shooting data including the shooting data re-acquired in the shooting data re-acquisition step The correction data is calculated.

Furthermore, the invention according to claim 2 that achieves the above object sequentially displays test patterns on the image display device based on the test pattern data, and obtains a plurality of test pattern imaging data by photographing the sequential test patterns. At the same time, an image when the image display device is not displayed is photographed to obtain external light component photographing data other than the test pattern, and the external light component photographing data is subtracted from each of the plurality of test pattern photographing data. A display characteristic correction data calculation method of an image display device for calculating correction data for correcting display characteristics of the image display device based on a plurality of photographing data obtained as described above,
An imaging data analysis process for analyzing the plurality of imaging data and detecting the presence or absence of abnormal imaging data;
When abnormal shooting data is detected in the shooting data analysis step, a shooting data re-acquisition step for re-acquisition of shooting data corresponding to the test pattern data when the abnormal shooting data is acquired,
When abnormal shooting data is detected in the shooting data analysis step, to correct display characteristics of the image display device based on a plurality of shooting data including the shooting data re-acquired in the shooting data re-acquisition step The correction data is calculated.

The invention according to claim 3 is the display characteristic correction data calculation method of the image display device according to claim 1 or 2, wherein the test patterns are sequentially displayed by test pattern data of different gradations,
The shooting data analysis step calculates a luminance change between sequential shooting data, and the luminance change and an allowable luminance change range set in advance corresponding to a gradation change between test pattern data in the sequential shooting data. , And the presence or absence of abnormal photographing data is detected.

The invention according to claim 4 is the display characteristic correction data calculation method of the image display device according to claim 1 or 2, wherein the test patterns are sequentially displayed by test pattern data of the same gradation,
The shooting data analysis step calculates the average brightness value of each shooting data, compares each brightness average value with the allowable brightness average value range preset for the gradation of the test pattern data, It is characterized by detecting the presence or absence of photographic data.

  The invention according to claim 5 is the display characteristic correction data calculation method of the image display device according to any one of claims 1 to 4, wherein the imaging data reacquisition step is performed when abnormal imaging data is acquired. The test pattern is re-displayed with the test pattern data, the re-displayed test pattern is photographed, and photographing data in place of the abnormal photographing data is re-acquired.

  According to a sixth aspect of the present invention, in the display characteristic correction data calculation method for an image display device according to any one of the first to fourth aspects, the photographing data reacquisition step includes photographing data in place of abnormal photographing data. The image data is re-acquired by calculation based on other image data excluding the abnormal image data.

  According to a seventh aspect of the present invention, in the display characteristic correction data calculation method for an image display device according to any one of the first to sixth aspects, the display characteristics include color characteristics, luminance characteristics, white balance characteristics, and gamma characteristics. It is characterized by including at least one of these.

Further, according to an eighth aspect of the invention for achieving the above object, a test pattern is sequentially displayed on an image display device based on test pattern data of different gradations, and a plurality of test patterns are photographed. A display characteristic correction data calculation program for an image display device that calculates correction data for correcting display characteristics of the image display device based on the acquired plurality of shooting data,
The luminance change between the acquired sequential shooting data is calculated, and the luminance change is compared with a preset allowable luminance change range corresponding to the gradation change between the test pattern data in the sequential shooting data. To detect the presence or absence of abnormal shooting data outside the allowable luminance change range,
When abnormal shooting data is detected, the test pattern is re-displayed with the test pattern data of the gradation from which the abnormal shooting data was acquired, and the above-described abnormal shooting data is shot by shooting the re-displayed test pattern. In this case, it is possible to re-acquire photographic data instead of the calculation data and calculate correction data for correcting the display characteristics of the image display device.

Furthermore, in the invention according to claim 9 for achieving the above object, a plurality of test patterns are sequentially displayed on an image display device on the basis of test pattern data of the same gradation, and a plurality of test patterns are photographed. A display characteristic correction data calculation program for an image display device that calculates correction data for correcting display characteristics of the image display device based on the acquired plurality of shooting data,
The luminance average value of each of the acquired shooting data is calculated, and the luminance average value is compared with the allowable luminance average value range set in advance for the gradation of the test pattern data. Detect the presence or absence of abnormal shooting data out of range,
When abnormal shooting data is detected, the test pattern is redisplayed with the test pattern data, and the redisplayed test pattern is shot and the shooting data in place of the abnormal shooting data is reacquired. Correction data for correcting display characteristics of the image display device is calculated.

Furthermore, the invention of the display characteristic correction data calculation device of the image display device according to claim 10 that achieves the above object is an image display device that sequentially displays test patterns based on the test pattern data, and photographs the sequential test patterns. An imaging device that acquires a plurality of imaging data, an arithmetic device that calculates correction data for correcting display characteristics of the image display device based on the plurality of imaging data, and a correction calculated by the arithmetic device An image correction device that corrects display data of the image display device based on the data,
The arithmetic device includes a photographing data storage unit that stores a plurality of photographing data photographed by the photographing device, and photographing that detects abnormal photographing data by analyzing the plurality of photographing data stored in the photographing data storage unit. When abnormal imaging data is detected based on the analysis result of the data analysis unit and the imaging data analysis unit, the test pattern of the test pattern data when the abnormal imaging data is acquired is displayed again and the imaging is performed. A re-display control unit that re-acquires data, a storage data control unit that complements the abnormal imaging data stored in the imaging data storage unit with the re-acquired imaging data, and the imaging data storage unit And a correction data calculation unit that calculates correction data based on a plurality of photographing data.

According to an eleventh aspect of the present invention, in the display characteristic correction data calculating device for the image display device according to the tenth aspect, the image display device is configured to sequentially display test patterns of test pattern data of different gradations, and
The shooting data analysis unit calculates a luminance change between sequential shooting data stored in the shooting data storage unit, and corresponds to the luminance change and a gradation change between test pattern data in the sequential shooting data. And a predetermined allowable luminance change range is compared, and photographing data outside the allowable luminance change range is detected as abnormal photographing data.

According to a twelfth aspect of the present invention, in the display characteristic correction data calculation device for the image display device according to the tenth aspect, the image display device is configured to sequentially display test patterns of test pattern data of the same gradation,
The photographic data analysis unit calculates an average luminance value of each photographic data stored in the photographic data storage unit, and an allowable luminance average preset for each luminance average value and the gradation of the test pattern data It is characterized by comparing the value range and detecting the shooting data out of the allowable luminance average value range as abnormal shooting data.

  According to the present invention, when abnormal shooting data is taken in when outside light changes or shooting is blocked by an obstacle while shooting a test pattern, the abnormal shooting data is taken. Is supplemented with correct shooting data, so that correct correction data can always be calculated without blocking external light by a dark screen or the like, and a high-quality image can be displayed easily at low cost.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 to 10 show a first embodiment of the present invention, and FIG. 1 shows a schematic configuration of an image display apparatus.

  The image display apparatus according to the present embodiment is called a multi-projection system, and is supplied from a plurality (four in this case) of projectors 1 constituted by liquid crystal projectors, a recording medium, a communication circuit, and the like. An image processing device 2 that generates and outputs a partial image to be projected from each projector 1 based on still image data or moving image data, and a screen 5 on which the partial image from each projector 1 is projected; The partial images from the projectors 1 are superimposed on the adjacent partial images at the edges thereof and projected and arranged on the screen 5, thereby constituting one image as a whole.

  In such a multi-projection system, as described above, the display characteristics may not be uniform in each projector 1 or in the relative relationship between the projectors 1.

  Therefore, it is necessary to correct such display characteristics when the multi-projection system is manufactured, installed, or maintained after installation. For this purpose, the display characteristic correction data calculation device includes a digital camera 4 as a photographing device and a computer 3 as a calculation device.

  The digital camera 4 captures an image displayed in the display area of the screen 5 and generates electronic captured image data.

  Here, the digital camera 4 is used as the photographing apparatus, but the present invention is not limited to this. For example, the photographing is performed using a silver halide camera, and a print created from the film directly or after being developed, It is also possible to generate photographed image data by scanning with a scanner or the like. Furthermore, for example, a line sensor or the like may be used to directly scan the display area of the screen 5 to obtain electronic photographed image data.

  The computer 3 controls the entire system and performs various calculations and processes. For example, a test pattern is generated and displayed on the screen 5 by the projector 1 via the image processing apparatus 2 and displayed. The pattern is captured by the digital camera 4, the shooting data acquired from the digital camera 4 is analyzed, and the screen 5 is exposed to external light and is brightened abnormally or between the digital camera 4 and the screen 5. By detecting shooting data that is abnormally dark across a person, etc., redisplaying the test pattern that was projected in the shooting data that detected the abnormality, recapturing the shooting data, Correction data from which the influence of obstacles and obstacles has been removed is calculated.

  Thus, by setting the correction data calculated by the computer 3 in the image processing apparatus 2, the multi-projection system is corrected even if the digital camera 4 and the computer 3 are removed from the multi-projection system. A high-quality image can be displayed.

  FIG. 2 is a block diagram showing a functional configuration of the display characteristic correction system in the multi-projection system of the present embodiment.

  The display characteristic correction system includes a control unit 11 for controlling the entire system, a test pattern generation unit 12 for generating test pattern data for obtaining display characteristic correction data (image correction data), and the test pattern generation. An image display unit 13 that performs display based on the test pattern data generated by the unit 12, a test pattern imaging unit 14 that captures the test pattern displayed on the image display unit 13 and outputs captured data, and a test pattern An imaging data storage unit 15 that stores image data output from the imaging unit 14, an analysis of the stored imaging data, whether the image display unit 13 is irradiated with external light, is not abnormally bright, or a person or the like An imaging data analysis unit 16 that detects abnormalities that are not darkened across the camera and an imaging data analysis unit 16 A re-display control unit 17 for instructing the test pattern generation unit 12 to generate the test pattern recorded in the detected shooting data again, display it on the image display unit 13 and re-shoot, and the shooting data analysis unit The storage data control unit 18 that erases the imaging data in which the abnormality is detected in 16 and supplements the imaging data that has been re-photographed according to the instruction of the re-display control unit 17, and image correction data that calculates image correction data based on the imaging data A calculation unit 19 and an image correction unit 20 that corrects image data to be displayed on the image display unit 13 based on the image correction data calculated by the image correction data calculation unit 19 are provided.

  Here, the test pattern photographing unit 14 corresponds to the digital camera 4 in FIG. 1, the image display unit 13 corresponds to the projector 1 and the screen 5, and the image correction unit 20 corresponds to the image processing device 2.

  The other components, that is, the control unit 11, the test pattern generation unit 12, the shooting data storage unit 15, the shooting data analysis unit 16, the redisplay control unit 17, the storage data control unit 18, and the image correction data calculation unit 19 are as follows. Corresponds to the computer 3.

  This display characteristic correction system functions by executing a display characteristic correction data calculation program on the operating system of the computer 3.

  Hereinafter, an outline of the operation of the display characteristic correction system shown in FIG. 2 will be described with reference to the flowchart shown in FIG.

  First, based on the control of the control unit 11, the test pattern generation unit 12 generates test pattern data for correcting display characteristics (step S1). The test pattern data is configured to clarify display characteristics such as geometric characteristics, color characteristics, luminance characteristics, white balance characteristics, gamma characteristics, and the like of the image display device. Only one test pattern may be used to calculate correction data for a plurality of display characteristics, or different test pattern data may be generated for each display characteristic to be corrected. .

  The test pattern data generated by the test pattern generation unit 12 is sent to the image display unit 13 and displayed as a test pattern (step S2). Specifically, the test pattern data is converted into partial image data corresponding to each projector 1 by the image processing device 2, and each projector 1 projects these partial image data, whereby a test pattern is displayed on the screen 5. Is done. The test pattern displayed on the screen 5 is photographed by the test pattern photographing unit 14, that is, the digital camera 4, and output as photographing data (step S3).

  This photographing data is stored in the photographing data storage unit 15 such as an internal buffer memory or a hard disk via an interface provided in the computer 3 (step S4).

  If there are a plurality of test patterns for calculating correction data, it is determined whether or not the test pattern ends when the i-th test pattern is stored (step S5). If not completed, i is incremented. (Step S6) The next (i + 1) th test pattern is displayed and the steps from S1 to S5 are repeated until the correction data is completed.

  Even when a plurality of correction data does not exist, the same test pattern is repeatedly displayed and stored in order to improve the correction accuracy. In this case, the steps from S1 to S5 are repeated until the predetermined number of measurements is completed.

  When the series of shooting data is stored, the shooting data analysis unit 16 detects whether there is any abnormal shooting data (step S7).

  Hereinafter, the processing in step S7 will be described with reference to FIG. 4 to FIG. 6 by taking as an example the case of calculating gamma characteristic correction data as correction data.

  FIG. 4 shows a change (a) in the shooting data of the test pattern in a normal state when calculating correction data of the gamma characteristic, and a luminance change (b) in the shooting data, respectively. FIG. A change (a) in the photographic data of the test pattern and a luminance change (b) in the photographic data when the display unit 13 is irradiated with external light and an abnormality occurs are shown. FIG. 6 shows the configuration of the imaging data analysis unit 16 when calculating correction data for gamma characteristics. Here, as shown in FIG. 4B, a case is considered in which the luminance of the photographic data of the γ curve 1 is to be corrected to a characteristic such as the γ curve 2.

  In the normal state shown in FIG. 4, first, the input to the projector 1 is the luminance of the shooting data of the minimum gradation (here, gradation a) and the luminance of the shooting data of the maximum gradation (here, gradation e). The dynamic range of luminance is calculated from the above and applied to the γ curve 2 to calculate the target luminance of each gradation. Subsequently, a ratio of the luminance of each gradation actually captured with respect to the target luminance is obtained and set as a coefficient αx, and a table of gamma correction coefficients is created. This table is stored in the image correction unit 20 in FIG. 2 and is applied to the input to the projector 1 to correct the gamma characteristic.

  However, as shown in FIG. 5A, in the middle of this example, in the case of this example, at gradation b, when the external light changes, the brightness of the shooting data is higher than the brightness actually projected from the projector 1. Thus, the γ curve 3 as shown in FIG. 5B is obtained, and the coefficient αb becomes abnormally small. For this reason, if this is stored in the image correction unit 20 as it is, when the gradation of the luminance b is input to the projector 1, the luminance projected by the projector 1 becomes low, resulting in an unnatural image. .

  Therefore, before the correction coefficient is obtained, in order to recognize whether there is an abnormality by analyzing the photographic data, the photographic data analysis unit 16 calculates the change rate of the luminance of the photographic data between each gradation, and the change rate. Detects an abnormally small or abnormally large gradation.

  For this reason, as shown in FIG. 6, in the shooting data analysis unit 16, first, the shooting data luminance calculation unit 32 of the gradation i and the shooting data luminance calculation unit of the gradation i + 1 from the sequential shooting data 31 of the gradation are stored. 33 calculates the luminance of the shooting data of the adjacent gradation, and calculates the change rate of the luminance of the shooting data with respect to the increment of the test pattern gradation based on the calculated luminance. .

  Subsequently, in the change rate comparison unit 35, the luminance change rate calculated by the change rate calculation unit 34 is compared with the luminance change rate according to the gradation change stored in the luminance change table 36 by the gradation change. If the rates of change match, True (T) is output, and if they do not match, False (F) is output. This is calculated for the gradation of the test pattern, and an abnormality presence / absence table 37 for each gradation is generated and transferred to the re-display control section 17 (see FIG. 2) at the subsequent stage of the imaging data analysis section 16 to determine which gradation level. Determine whether to redisplay and re-shoot the test pattern.

  Specifically, for example, when the test pattern data of gradation a and the test pattern data of gradation b that are input to the projector 1 are displayed, since the change in gradation is known, the change in the luminance to be photographed is also to some extent. I have an expectation. The standard value of the luminance change rate is set in consideration of the variation of the gamma characteristic of the projector and the variation of the gamma characteristic of the camera side, and is stored in the luminance change table 36. In the case of FIG. 4B, the standard value of the luminance change of the gradation b is 1.8 times, and the standard value is set to 1.6 to 2.0 times.

  Here, the luminance of the shooting data luminance of the gradation a is calculated by the shooting data luminance calculation unit 32 of the gradation i, and the luminance of the shooting data of the gradation b is calculated by the shooting data luminance calculation unit 33 of the gradation i + 1. Then, the change rate calculation unit 34 calculates the change rate from the gradation a to the gradation b from the luminance of both.

  In this case, as shown in FIG. 4B, the luminance change is calculated as 1.8 times and is within the standard range of the luminance change rate stored in the luminance change table 36 in the normal state. When the external light changes, the screen 5 is irradiated with light other than that projected from the projector 1 and becomes abnormally bright. Therefore, in the case of FIG. It is determined by the rate comparison unit 35 that the standard value 1.8 times and the standard width 1.6 to 2.0 times stored in the luminance change table 36 due to gradation change are significantly different from the numbers. It is detected that the key b data is abnormal, and F (abnormal) is stored in the abnormality presence / absence table 37.

  In addition to the above, the abnormality detection method for photographing data when obtaining correction data of gamma characteristics can be detected by determining whether the absolute value of each luminance is within an allowable range. In addition, since the gamma characteristic of the projector 1 is generally monotonically increasing, it is regarded as abnormal when the brightness of the shooting data is lowered during the sequential shooting with increasing gradation, and the data before and after that is regarded as abnormal. You may take it again.

  In this embodiment, the calculation function of the computer 3 (see FIG. 1) is used to obtain gamma characteristic correction data. For example, the photographing data 31 in FIG. A memory element such as a DRAM for storing image data, an arithmetic element such as a DSP for performing calculations such as the photographing data luminance calculation units 32 and 33, the change rate calculation unit 34, and the change rate comparison unit 35; A hardware configuration using a CPU for generating the repetitive control and the abnormality presence / absence table 37 may be used. Further, the gamma characteristic correction data may be set for each pixel or each pixel block of the projector 1, or may be set for each projector 1 or for all the projectors 1, and in accordance with the above-described gradation intervals. What is necessary is just to calculate the change rate of. Further, as a method of obtaining the rate of change in luminance depending on the gradation input to the projector 1, an external detector for measuring the brightness of the screen may be provided without using shooting data, and the rate may be obtained based on the output. .

  Next, calculation of white balance (WB) characteristic correction data will be described with reference to FIGS.

  FIG. 7 shows the shooting data (a) of the test pattern under normal conditions and the luminance (b) of the shooting data when calculating the correction data of the white balance characteristic, and FIG. 8 shows the image display unit. 13 shows imaging data (a) including a case where an abnormality occurs due to external light irradiation, and luminance (b) of the imaging data. 9A and 9B are diagrams showing white balance characteristics, where FIG. 9A shows an actual white balance (solid line) and a target white balance (dotted line) in a normal state, and FIG. 9B shows an external light irradiation. 10 shows the actual white balance when an abnormality occurs, and FIG. 10 shows the configuration of the photographic data analysis unit 16 when calculating correction data of the white balance characteristic.

In the present embodiment, a white screen is projected from the projector 1 as a test pattern, and the luminance of each color of RGB is calculated from the obtained shooting data. If the luminance balance of each RGB color is poor, the color will appear unnatural. Therefore, a coefficient of the luminance balance of each actually captured RGB color with respect to the ideal luminance balance of each RGB color is calculated, and the correction coefficient β _The white balance characteristics are corrected by storing them as _{R 1} , β _G , and β _{B in} the image correction unit 20 of FIG.

Usually, in order to increase the accuracy, the same test pattern is repeatedly photographed several times, and the correction coefficients β _R , β _G , β _B are calculated by averaging the brightness of the photographed data. Here, the average of five times is obtained, but when the external light changes in the middle as shown in FIG. 8, the external light is irradiated to the second photographing data, as shown in FIG. 9B. White balance data has been obtained. For this reason, if the correction coefficients β _R , β _G , and β _B are calculated by adding the abnormal data to the data to be averaged, a correction coefficient that is far from the white balance originally projected from the projector 1 is obtained.

  Therefore, before obtaining the correction coefficient, in order to recognize whether there is any abnormality by analyzing the photographic data, the photographic data analysis unit 16 calculates the luminance of each photographic data and its average, Image data whose ratio with the average exceeds a predetermined ratio is detected.

  For this reason, as shown in FIG. 10, the shooting data analysis unit 16 first calculates the luminance from the shooting data 41 stored in the i-th shooting data luminance calculation unit 42, and the luminance average calculation unit 43 calculates all the shooting data. Find the average of the brightness. Next, a ratio between the calculated average value of luminance and the luminance of each photographic data is calculated by the ratio calculation unit 44, and the ratio falls within a predetermined allowable error stored in the allowable error storage unit 46. The ratio determining unit 45 determines whether or not This calculation is repeated for the number of photographic data, an abnormality presence / absence table 47 is generated and transferred to the re-display control unit 17 (see FIG. 2) subsequent to the photographic data analysis unit 16, and the test pattern is displayed again. Determine whether to re-shoot.

  Specifically, for example, assuming that the photographing error stored in the allowable error storage unit 46 is ± 10%, in the normal state, as shown in FIG. If the ambient light changes within the range of ± 10%, as shown in FIG. 8B, the luminance of the second shooting data calculated by the i-th shooting data luminance calculation unit 42 is as shown in FIG. Since it deviates from the average luminance by + 25%, it is recognized that the second shooting data is abnormal.

  In addition to the above, the abnormality detection method of the image data when obtaining the correction data of the white balance characteristic can be detected by predicting the absolute value of the luminance and determining whether it is within the allowable range. In the above description, the abnormality is detected from the change in the luminance of the photographing data. However, the abnormality can be detected by calculating the luminance for each color of RGB and detecting that the white balance is shifted.

  In the present embodiment, the calculation function of the computer 3 (see FIG. 1) is used to obtain white balance characteristic correction data. For example, the photographing data 41 in FIG. A memory element such as a DRAM for storing an error, and an arithmetic element such as a DSP for calculating, such as a photographing data luminance calculation unit 42, a luminance average calculation unit 43, a ratio calculation unit 44, and a ratio determination unit 45; It may be configured in hardware using a CPU for generating repetitive control of computation and the abnormality presence / absence table 47. The white balance characteristic correction data may be set for each pixel or pixel block of the projector 1 or may be set for each projector 1 or for all the projectors 1, and the above-described shooting data may be set accordingly. The rate of change between them may be calculated. Further, as a method for obtaining a change in the luminance of the screen 5, a detector for measuring the brightness of the screen may be provided outside without using photographing data, and the change may be obtained based on the output.

  As described above, when the imaging data is analyzed in step S7 in FIG. 3 to detect an abnormality, the same test pattern is generated in the test pattern generation unit 12 in order to re-image the imaging data in which the abnormality is detected. The test pattern displayed on the image display unit 13 is photographed by the test pattern photographing unit 14 and replaced with abnormal photographing data (steps S8 and S9). Thereafter, whether or not the replaced photographing data is abnormal is analyzed again in step S7. If there is no abnormality, correction data for each characteristic is calculated (step S10).

  FIG. 11 is a flowchart showing the operation of the image display apparatus according to the second embodiment of the present invention.

  In the present embodiment, correction data is calculated by removing the influence of external light constantly radiated on the screen 5 in the multi-projection system having the same configuration as that of the first embodiment. In the flowchart shown in FIG. 6, prior to step S1, step S11 for photographing the non-display screen 5 where nothing is projected from the projector 1 is first added, and the test is performed between step S3 and step S4. Step S12 for subtracting the non-display external light component image data captured in step S11 from the pattern image data is added, and based on the image data obtained in step S12, the same as in the first embodiment. Thus, the display characteristic correction data is calculated.

  Therefore, according to the present embodiment, it is possible to remove not only the influence of incident external light incidentally only at the time of photographing a test pattern but also the influence of external light that is radiated constantly. It is possible to calculate with high accuracy and display a higher quality image.

  The present invention is not limited to the present embodiment described above, and many changes or modifications can be made. For example, in the above-described embodiment, when abnormal shooting data is detected, shooting is performed again, but it may be supplemented from previous and subsequent data without shooting again. Also, not only when the screen is exposed to external light, but also when the shooting data is blocked, such as when a person passes in front of the camera, the brightness of the shooting data is greatly reduced. The correct correction data can be obtained by detecting the corrected part and projecting the same test pattern to complement or complementing from the preceding and succeeding data.

  Furthermore, the present invention is not limited to the case where a projector is used as a video device, but can be effectively applied to a case where a CRT, LCD, plasma display, organic EL, LCD display panel, paper display, or the like is used, and a plurality of video devices. The present invention is not limited to the calculation of the display characteristic correction data of the image display apparatus having the above, and can be effectively applied to the calculation of the display characteristic correction data of the image display apparatus having one video apparatus. The present invention is not limited to the above-described calculation of correction data for gamma characteristics and white balance characteristics, but can be effectively applied to the case of calculating correction data for other display characteristics such as color characteristics and luminance characteristics. .

1 is a diagram showing a schematic configuration of an image display device according to a first embodiment of the present invention. It is a block diagram which shows the functional structure of the display characteristic correction | amendment system in the multi-projection system of 1st Embodiment. 3 is a flowchart showing an outline of the operation of the display characteristic correction system shown in FIG. 2. FIG. 6 is a diagram illustrating a change in shooting data of a test pattern at a normal time and a change in luminance of the shooting data when calculating gamma characteristic correction data in the first embodiment. Similarly, it is a figure which shows the change of the imaging | photography data of a test pattern when the external light is irradiated, and the brightness | luminance change of the imaging | photography data when abnormality generate | occur | produces. FIG. 3 is a block diagram showing the configuration of the imaging data analysis unit shown in FIG. 2 when calculating gamma characteristic correction data. FIG. 6 is a diagram illustrating shooting data of a test pattern at a normal time when calculating correction data of white balance characteristics and luminance of the shooting data in the first embodiment. Similarly, it is a figure which shows the imaging | photography data including the case where abnormality generate | occur | produces by external light irradiation, and the brightness | luminance of the imaging | photography data. Similarly, it is a figure which shows a white balance characteristic. Similarly, it is a block diagram showing a configuration of a photographing data analysis unit shown in FIG. 2 when calculating correction data of white balance characteristics. It is a flowchart which shows operation | movement of the image display apparatus in 2nd Embodiment of this invention. It is a figure which shows the state by which external light was irradiated to the display screen. It is a figure for demonstrating the prior art.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Projector 2 Image processing apparatus 3 Computer (arithmetic unit)
4 Digital camera (photographing device)
DESCRIPTION OF SYMBOLS 5 Screen 11 Control part 12 Test pattern production | generation part 13 Image display part 14 Test pattern imaging | photography part 15 Imaging | photography data storage part 16 Imaging | photography data analysis part 17 Redisplay control part 18 Memory | storage data control part 19 Image correction data calculation part 20 Image correction part 32 Shooting data luminance calculation unit for gradation i 33 Shooting data luminance calculation unit for gradation i + 1 34 Change rate calculation unit 35 Change rate comparison unit 36 Brightness change table by gradation change 37 Abnormality presence / absence table 42 i-th shooting data luminance calculation unit 43 luminance average calculation unit 44 ratio calculation unit 45 ratio determination unit 46 allowable error storage unit 47 abnormality presence / absence table

Claims (12)

A test pattern is sequentially displayed on the image display device based on the test pattern data, and the sequential test pattern is photographed to obtain a plurality of photographing data, and the display of the image display device is based on the obtained plurality of photographing data. A display characteristic correction data calculation method for an image display device for calculating correction data for correcting characteristics,
An imaging data analysis process for analyzing the plurality of acquired imaging data and detecting the presence or absence of abnormal imaging data;
When abnormal shooting data is detected in the shooting data analysis step, a shooting data re-acquisition step for re-acquisition of shooting data corresponding to the test pattern data when the abnormal shooting data is acquired,
When abnormal shooting data is detected in the shooting data analysis step, to correct display characteristics of the image display device based on a plurality of shooting data including the shooting data re-acquired in the shooting data re-acquisition step The display characteristic correction data calculation method of the image display device, characterized in that the correction data is calculated. The test pattern is sequentially displayed on the image display device based on the test pattern data, and the sequential test pattern is photographed to obtain a plurality of test pattern photographing data, and at the same time, the image display device is not displayed. The image display device based on a plurality of imaging data obtained by acquiring external light component imaging data other than the test pattern by subtracting the external light component imaging data from each of the plurality of test pattern imaging data A display characteristic correction data calculation method for an image display device for calculating correction data for correcting display characteristics of
An imaging data analysis process for analyzing the plurality of imaging data and detecting the presence or absence of abnormal imaging data;
When abnormal shooting data is detected in the shooting data analysis step, a shooting data re-acquisition step for re-acquisition of shooting data corresponding to the test pattern data when the abnormal shooting data is acquired,
When abnormal shooting data is detected in the shooting data analysis step, to correct display characteristics of the image display device based on a plurality of shooting data including the shooting data re-acquired in the shooting data re-acquisition step The display characteristic correction data calculation method of the image display device, characterized in that the correction data is calculated. The above test patterns are displayed sequentially with test pattern data of different gradations,
The shooting data analysis step calculates a luminance change between sequential shooting data, and the luminance change and an allowable luminance change range set in advance corresponding to a gradation change between test pattern data in the sequential shooting data. The display characteristic correction data calculation method for the image display device according to claim 1, wherein presence / absence of abnormal photographing data is detected by comparing the two. The above test patterns are sequentially displayed with test pattern data of the same gradation,
The shooting data analysis step calculates the average brightness value of each shooting data, compares each brightness average value with the allowable brightness average value range preset for the gradation of the test pattern data, 3. The display characteristic correction data calculation method for an image display device according to claim 1, wherein presence / absence of correct photographing data is detected.   The imaging data re-acquisition step re-displays the test pattern with the test pattern data obtained when the abnormal imaging data is acquired, captures the re-displayed test pattern, and captures imaging data in place of the abnormal imaging data. 5. The display characteristic correction data calculation method for an image display device according to claim 1, wherein the display characteristic correction data is acquired again.   5. The photographing data reacquisition step re-acquires photographing data instead of abnormal photographing data by calculation based on other photographing data excluding the abnormal photographing data. A display characteristic correction data calculation method for an image display device according to one item.   The display characteristic correction data calculation of the image display device according to claim 1, wherein the display characteristic includes at least one of a color characteristic, a luminance characteristic, a white balance characteristic, and a gamma characteristic. Method. The computer causes the image display device to sequentially display the test patterns based on the test pattern data of different gradations, captures the sequential test patterns, acquires a plurality of shooting data, and the acquired plurality of shooting data A display characteristic correction data calculation program for an image display device for calculating correction data for correcting display characteristics of the image display device based on
The luminance change between the acquired sequential shooting data is calculated, and the luminance change is compared with a preset allowable luminance change range corresponding to the gradation change between the test pattern data in the sequential shooting data. To detect the presence or absence of abnormal shooting data outside the allowable luminance change range,
When abnormal shooting data is detected, the test pattern is re-displayed with the test pattern data of the gradation from which the abnormal shooting data was acquired, and the above-described abnormal shooting data is shot by shooting the re-displayed test pattern. A display characteristic correction data calculation program for an image display device, characterized in that correction data for correcting the display characteristics of the image display device is calculated by re-acquisition of shooting data instead of the above. The computer causes the image display device to sequentially display the test patterns based on the test pattern data of the same gradation, captures the sequential test patterns, acquires a plurality of shooting data, and obtains the acquired plurality of shooting data. A display characteristic correction data calculation program for an image display device for calculating correction data for correcting display characteristics of the image display device based on
The luminance average value of each of the acquired shooting data is calculated, and the luminance average value is compared with the allowable luminance average value range set in advance for the gradation of the test pattern data. Detect the presence or absence of abnormal shooting data out of range,
When abnormal shooting data is detected, the test pattern is redisplayed with the test pattern data, and the redisplayed test pattern is shot and the shooting data in place of the abnormal shooting data is reacquired. A display characteristic correction data calculation program for an image display apparatus, wherein correction data for correcting display characteristics of the image display apparatus is calculated. An image display device that sequentially displays test patterns based on test pattern data, an image capturing device that captures the sequential test patterns and obtains a plurality of image data, and an image display device based on the plurality of image data. An arithmetic device that calculates correction data for correcting display characteristics, and an image correction device that corrects display data of the image display device based on the correction data calculated by the arithmetic device,
The arithmetic device includes a photographing data storage unit that stores a plurality of photographing data photographed by the photographing device, and photographing that detects abnormal photographing data by analyzing the plurality of photographing data stored in the photographing data storage unit. When abnormal imaging data is detected based on the analysis result of the data analysis unit and the imaging data analysis unit, the test pattern of the test pattern data when the abnormal imaging data is acquired is displayed again and the imaging is performed. A re-display control unit that re-acquires data, a storage data control unit that complements the abnormal imaging data stored in the imaging data storage unit with the re-acquired imaging data, and the imaging data storage unit A display data correction data calculation device for an image display device, comprising: a correction data calculation unit that calculates correction data based on a plurality of photographing data The image display device is configured to sequentially display test patterns of different gradation test pattern data,
The shooting data analysis unit calculates a luminance change between sequential shooting data stored in the shooting data storage unit, and corresponds to the luminance change and a gradation change between test pattern data in the sequential shooting data. The image display device according to claim 10, wherein the image data is compared with an allowable luminance change range set in advance and image data out of the allowable luminance change range is detected as abnormal image data. Display characteristic correction data calculation device. The image display device is configured to sequentially display test patterns of the same gradation test pattern data, and
The photographic data analysis unit calculates an average luminance value of each photographic data stored in the photographic data storage unit, and an allowable luminance average preset for each luminance average value and the gradation of the test pattern data 11. The display characteristic correction data calculation of the image display device according to claim 10, wherein the image data is compared with a value range and image data outside the allowable luminance average value range is detected as abnormal image data. apparatus.

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