JP2006245914A - Image-correcting device, image correcting method, and image-correcting system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image correcting device which is capable of displaying projected images which have no shadows due to corrected projected images. <P>SOLUTION: The image-correcting device 2 is equipped with a correcting device body 21 which forms optically modulated image light, projects it onto a screen Sc as it is enlarged so as to superpose it on the projected image projected onto the screen Sc by an image projection device 3, a control device 23 which enables the correcting device body 21 to form a prescribed image light, and an image sensing device 22 which photos the projection surface of the screen Sc. The control device 23 is equipped with a shadow region discriminating unit 233, which calculates the brightness of the projected image at the prescribed positions on the image based on the image photoed by the image sensing device 22, and decides a shadow region, whose brightness is lower than a first threshold in the projected image; and a liquid crystal panel drive/control unit 234 which decides a shadow corresponding region, corresponding to the shadow region in the inputted image, on the basis of image signals corresponding to the acquired projected image, and enables the correction device body 21 to form an image light, where the shadow corresponding region is higher in brightness than the other regions in the inputted image. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image correction apparatus, an image correction method, and an image correction system.

2. Description of the Related Art Conventionally, a projector (image projection apparatus) that modulates and projects a luminous flux emitted from a light source according to image information has been used (see, for example, Patent Document 1). Such projectors are used for various purposes, such as giving presentations on personal computers in a company, watching movies, etc. at home.
The projector includes a light source device, a light modulation device that modulates a light beam emitted from the light source device to form image light, and obtains a predetermined image signal and forms image light based on the image signal in the light modulation device. And a projection optical device for enlarging and projecting image light formed by the light modulation device toward the screen to form a predetermined projection image.

JP 2001-356415 A

By the way, when a projection image is formed on a screen using the projector described in Patent Document 1, if a shielding object (such as a person) enters between the projector and the screen, an enlarged projection is performed. A part of the image light is blocked by the shielding object, and a shadow is generated in a part of the projection image.
Conventionally, in order to eliminate the shadow generated in the projected image, the projector is moved or the projection direction of the projector is changed to avoid the shielding object and project the image light. However, in such a method, it is necessary for the user to perform a complicated operation of moving the projector and changing the projection direction.
Therefore, there is a demand for a technique that corrects a projected image and eliminates a shadow generated in the projected image without causing the user to perform complicated work.

  An object of the present invention is to provide an image correction apparatus, an image correction method, and an image correction apparatus capable of correcting a projection image and displaying a projection image without a shadow on the screen even when a shadow occurs on the projection image on the screen due to an obstacle. And providing an image correction system.

  An image correction apparatus of the present invention is an image correction apparatus that corrects a projected image projected on a screen, which modulates a light beam emitted from a light source to form image light, and the formed A correction apparatus main body including a projection optical device that magnifies and projects image light onto the screen and superimposes the image light on the projection image, and drives the light modulation device to control the light modulation device with predetermined image light. A control device to be formed; and an imaging device that images the projection surface of the screen. The control device, based on an image captured by the imaging device, has each luminance at a predetermined plurality of positions in the projection image. The projection image luminance value calculation unit for calculating the value and each luminance value in the projection image calculated by the projection image luminance value calculation unit are compared with the first threshold value. A shadow area determination unit that determines a shadow area that is equal to or less than a first threshold, and an image signal corresponding to the projection image is acquired, and a shadow corresponding to the shadow area in the input image based on the acquired image signal A shadow-corresponding region determination unit that determines a region-corresponding region; and driving control of the light modulation device, and image light having a luminance value of the shadow-corresponding region in the input image higher than that of other regions And a display control unit formed in the modulation device.

In the present invention, since the image correction device includes the correction device main body, the control device, and the imaging device, the projection image projected on the screen can be corrected by the image correction device as shown below.
First, the imaging device captures a projection surface (projected image) of the screen and outputs a signal based on the captured image to the control device. The projection image luminance value calculation unit of the control device recognizes the projection image projected on the screen based on the signal output from the imaging device, and calculates each luminance value at a plurality of predetermined positions in the projection image. To do. The shadow area determination unit of the control device compares each luminance value in the projection image calculated by the projection image luminance value calculation unit with a predetermined first threshold value. Then, the shadow area determination unit determines an area having a luminance value equal to or lower than the first threshold in the projection image as a shadow area that is a shadow area generated in the projection image. The shadow corresponding area determination unit of the control device acquires an image signal corresponding to the projection image projected on the screen, and recognizes an input image based on the acquired image signal. The shadow corresponding area determination unit acquires the shadow area determined by the shadow area determination unit and determines a shadow corresponding area corresponding to the shadow area in the projection image in the recognized input image. To do. Then, the display control unit of the control apparatus acquires the shadow corresponding region determined by the shadow corresponding region determination unit, and the luminance value in the shadow corresponding region in the input image is the luminance of the region other than the shadow corresponding region. Image light higher than the value is formed in the light modulation device of the correction device body. Thereafter, the image light formed by the light modulation device is enlarged and projected onto the screen by the projection optical device of the correction device body, and is superimposed on the projection image. That is, image light that includes an image that is substantially the same as the projected image by the image correction device in the projected image projected on the screen (image light in which the luminance value in the area determined to be a shadow is higher than the luminance value in the other area) ) Is superimposed.
Therefore, even when a shadow is generated in the projection image projected on the screen, an image that is originally projected in the shadow portion can be formed in the shadow portion of the projection image, and the projection image is corrected to have no shadow. Projected images can be displayed on the screen.
In addition, since the image light whose luminance value in the area determined to be a shadow is higher than the luminance value in the other area is superimposed on the projection image, for example, an image including the same image as the projection image by the image correction device Compared to the case where light is superimposed (in the case of normal stack projection), extreme changes in the luminance value between the shadow area and other areas in the projection image are reduced, and the projection image has no sense of incongruity. Can do.

In the image correction device of the present invention, the control device acquires an image signal corresponding to the projection image, and calculates an input image luminance value at each of a plurality of predetermined positions in the input image based on the acquired image signal. Comparing each luminance value in the input image calculated by the calculation unit and the input image luminance value calculation unit with a second threshold value, a dark area where the luminance value in the input image is equal to or less than the second threshold value It is preferable that the shadow corresponding area determination unit corrects the shadow corresponding area by excluding the dark area from the shadow corresponding area in the input image.
In the present invention, the input image luminance value calculation unit constituting the control device acquires an image signal corresponding to the projection image, and recognizes an input image based on the acquired image signal. Further, the input image luminance value calculation unit calculates each luminance value at a predetermined plurality of positions in the recognized input image. In addition, the dark area determination unit included in the control device compares each luminance value in the input image calculated by the input image luminance value calculation unit with a predetermined second threshold value. Then, the dark area determination unit determines an area in the input image whose luminance value is equal to or less than the second threshold as a dark area that is originally dark in the input image (the luminance value is small). . The shadow-corresponding region determination unit corrects the shadow-corresponding region by removing the dark region from the shadow-corresponding region determined based on the shadow region determined by the shadow region determining unit.
Therefore, even when the shadow area determination unit determines the area including the originally dark area in the projection image as the shadow area, the input image luminance value calculation unit, the dark area determination unit, and the shadow corresponding area determination The shadow portion corresponding region can be determined by excluding the dark portion region that is originally formed dark, and the region that is originally formed dark in the projection image can be distinguished from the shadow portion region. For this reason, an image having a relatively high luminance value is not projected from the image correction apparatus onto the originally dark area in the projected image, and the originally dark area in the projected image is not projected. Thus, only the shadow generated in the projected image can be eliminated satisfactorily.

  In the image correction apparatus according to the aspect of the invention, the control device includes a shadow area information storage unit that stores shadow area information related to the previous shadow area, and the projection image calculated by the projection image luminance value calculation unit. Are stored in the shadow area information storage section and the shadow area information storage section for comparing each brightness value in the image with a third threshold value and determining a superimposed area in which the brightness value in the projection image is equal to or greater than the third threshold value. A shadow part that corrects the shadow area by adding the correction area obtained by removing the superimposition area from the previous shadow area based on the shadow area information and the shadow area determined by the shadow area determination unit It is preferable that the shadow-corresponding region determination unit determines a shadow-corresponding region corresponding to the corrected shadow region in the input image.

By the way, when the shielding object moves between the image projection apparatus and the screen, that is, when the position of the shadow area generated in the projection image changes, there are the following problems. In the following description, it is assumed that the shadow area has changed from the first position to the second position.
When the shadow area is located at the first position, as described above, the control device recognizes the shadow area, and the shadow area located at the first position has high brightness. A process of superimposing image light with low luminance on an area other than the shadow area to eliminate the shadow area is performed.
Here, when the shadow area changes from the first position to the second position, a part of the current shadow area overlaps with a part of the previous shadow area at the previous first position. The current shadow area and the previous shadow area are divided into three areas: the shadow area, the shadow area, and the new shadow area. Divided.

In the region that is no longer a shadow portion, an image projected from the image projection device and an image with a relatively high luminance value projected after the previous shadow portion region is determined by the image correction device are superimposed, An image having a higher luminance than the original image is formed.
Further, in the region that remains as the shadow portion, the image light projected from the image projection device is shielded by the shielding object, and the conventional shadow portion region is determined by the image correction device and projected relatively. Only images with high values are formed.
Further, the image light projected from the image projection apparatus is shielded by the shielding object in the newly shadowed area, and an image is not formed.
In this state, when the image correction device again determines the shadow area and superimposes the predetermined image light on the projection image, no image is formed in the newly shadow area. Then, it is determined that the area that has newly become a shadow portion has a luminance value equal to or less than the first threshold value, and the region that has become a shadow portion is determined as a shadow area. Then, image light having high brightness is superimposed only on the newly shaded area and low brightness is superimposed on other areas. However, since the original shadow area is an area that is the area that remains the shadow area and the area that is newly added as the shadow area, when the above-described processing is performed, the original shadow area The image light with high luminance is superimposed only on the newly shadowed area in the area, and the image light with low luminance is superimposed on the area that remains the shadow, thereby eliminating the original shadow area. Processing cannot be performed well.

In the present invention, the overlapping area determination unit that constitutes the control device compares each luminance value in the projection image calculated by the projection image luminance value calculation unit with a predetermined third threshold value. Then, the superimposition area determination unit has an image with a higher luminance than the original image in an area that is no longer the shadow area in the projection image. It is determined as an overlapping area that is an area that is equal to or greater than the third threshold. The shadow area correction unit included in the control device reads the shadow area information stored in the shadow area information storage unit included in the control apparatus, and reads the previous shadow area based on the shadow area information (the shadow area described above). And a region including the region that remains the shadow portion). In addition, the shadow area correction unit calculates a correction area (an area that remains the shadow area) obtained by excluding the overlap area determined by the overlap area determination unit from the previous shadow area. Further, the shadow area correction unit adds the area that remains the calculated shadow area and the shadow area determined by the shadow area determination section (the area that has newly become a shadow area) to add a shadow. The original shadow area is determined by correcting the partial area.
Accordingly, even when the shielding object moves between the image projection apparatus and the screen, that is, the position of the shadow area generated in the projected image changes, the original shadow area is accurately determined and It is possible to satisfactorily perform the process of eliminating the shadow area.

In the image correction apparatus according to the aspect of the invention, it is preferable that the projection image luminance value calculation unit and the input image luminance value calculation unit calculate a luminance value for each pixel in the entire image area.
In the present invention, since the projection image luminance value calculation unit and the input image luminance value calculation unit calculate the luminance value for each pixel in the entire image area, the shadow area, the dark area, and the overlapping area described above are the shadow area. The determination unit, the dark region determination unit, and the superimposition region determination unit determine the pixel unit, and the shadow region, the dark region, and the superimposition region can be determined more accurately. For this reason, the process which eliminates the shadow which generate | occur | produces in a projection image can be implemented more correctly, and it can be set as a projection image with a more uncomfortable feeling.

In the image correction apparatus according to the aspect of the invention, it is preferable that the display control unit causes the light modulation device to form image light that masks other regions other than the shadow portion corresponding region in the input image.
According to the present invention, the display control unit masks an area other than the area determined to be a shadow, and causes the light modulation device to form an image that should be originally displayed only in the area determined to be a shadow. The image contained in the image light projected from (image not masked) and the image displayed in the area other than the shadow in the projected image do not overlap, and the state of the projected image that should be originally displayed is set Therefore, it is possible to obtain a good projected image without a sense of incongruity.

The image correction method according to the present invention is an image correction method for correcting a projected image projected on a screen, the imaging step for imaging a projection surface of the screen, and the projected image based on the captured image. A luminance value calculating step for calculating each luminance value at a plurality of predetermined positions, a comparison step for comparing each luminance value in the calculated projection image with a first threshold, and a result of comparison in the comparison step , A shadow area determination step for determining a shadow area whose luminance value in the projection image is equal to or less than the first threshold value, an image signal corresponding to the projection image is acquired, and an input image based on the acquired image signal A shadow-corresponding region determination step for determining a shadow-corresponding region corresponding to the shadow region in the input image, and a luminance value of the shadow-corresponding region in the input image is a luminance value of another region An image light forming step of forming a remote high image light, characterized in that the image light and an image correcting step of superimposing the projected image enlarged and projected to toward the screen.
According to the present invention, an image correction method includes an imaging step, a luminance value calculation step, a comparison step, a shadow area determination step, a shadow area corresponding determination step, an image light formation step, and an image correction step. Therefore, the same operations and effects as those of the above-described image correction apparatus can be enjoyed.

An image correction system according to the present invention includes a light modulation device that forms image light by modulating a light beam emitted from a light source, and a control that acquires a predetermined image signal and forms image light based on the image signal in the light modulation device. An image projection apparatus configured to include a projection optical apparatus that forms a predetermined projection image by enlarging and projecting image light formed by the light modulation apparatus toward the screen, and the above-described image correction apparatus. And an image output device that outputs the same image signal to the image projection device and the image correction device.
According to the present invention, the image correction system includes the image projection device, the above-described image correction device, and the image output device, and therefore can enjoy the same operations and effects as the above-described image correction device.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[1. First Embodiment]
[1-1. Configuration of image correction system]
FIG. 1 is a diagram showing a schematic configuration of an image correction system 1 in the first embodiment.
The image correction system 1 uses the image correction device 2 and a shadow Sh appears on the projection image F0 formed on the screen Sc by the image projection device 3 with the shielding object C interposed between the image projection device 3 and the screen Sc. When this occurs, the projection image F0 is corrected so as to eliminate the shadow Sh0. As shown in FIG. 1, the image correction system 1 includes an image correction device 2, an image projection device 3, and an image output device 4.
The image output device 4 includes, for example, a PC (Personal Computer), a DVD (Digital Versatile Disc) player, and the like, and outputs the same image signal to the image projection device 3 and the image correction device 2.

The image projection device 3 receives the image signal output from the image output device 4, modulates the light beam emitted from the light source according to the image signal, forms image light, and enlarges and projects the formed image light Then, the projection image F0 is formed on the screen Sc. Although not specifically shown, the image projection device 3 is a light source device, a light modulation device that modulates a light beam emitted from the light source device to form image light, and an image signal output from the image output device 4. And a control device that causes the light modulation device to form image light based on the image signal, and the image light formed by the light modulation device is enlarged and projected toward the screen Sc to form a predetermined projection image F0 This is a general projector that includes a projection optical device.
Although specifically described later, the image correction device 2 inputs an image signal output from the image output device 4, forms predetermined image light in accordance with the image signal, and the image projection device 3 causes the image to be corrected on the screen Sc. Stack projection in which the formed predetermined image light is superimposed at the same position and the same size as the projection image F0 is performed on the projection image F0 formed in the above. Then, the image correction device 2 corrects the projection image F0 so as to eliminate the shadow Sh0 generated in the projection image F0.

[1-2. Configuration of image correction device]
FIG. 2 is a block diagram illustrating a configuration of the image correction apparatus 2.
As shown in FIG. 2, the image correction device 2 includes a correction device main body 21, an imaging device 22, and a control device 23.
Under the control of the control device 23, the correction device main body 21 forms predetermined image light, magnifies and projects it onto the screen Sc, and superimposes it on the projection image F0 on the screen Sc. As shown in FIG. 2, the correction device main body 21 includes a light source device 211, a liquid crystal light valve 212 as a light modulation device, a projection optical device 213, and the like.
The light source device 211 emits a light beam toward the liquid crystal light valve 212 under the control of the control device 23. The light source device 211 includes a light source lamp 211A and a lamp driving unit 211B.
The light source lamp 211A is composed of an ultrahigh pressure mercury lamp. It should be noted that other discharge light source lamps such as a metal halide lamp and a xenon lamp may be employed in addition to the ultra-high pressure mercury lamp. Furthermore, not only a discharge light source lamp, but various self-light emitting elements such as a light emitting diode, an organic EL (Electro Luminescence) element, and a silicon light emitting element may be employed.
The lamp driving unit 211B generates a driving signal according to a predetermined driving frequency under the control of the control device 23, and drives the light source lamp 211A.

The liquid crystal light valve 212 is a transmissive liquid crystal panel, changes the arrangement of liquid crystal molecules enclosed in a liquid crystal cell (not shown) based on a drive signal from the control device 23, and is emitted from the light source device 211. By transmitting or blocking the light beam, predetermined image light corresponding to the drive signal is emitted to the projection optical device 213.
The projection optical device 213 enlarges and projects the image light emitted from the liquid crystal light valve 212 toward the screen Sc and superimposes it on the projection image F0 on the screen Sc.
Although not shown, the image correction apparatus 2 includes three liquid crystal light valves 212 corresponding to the three colors RGB. The light source device 211 also includes a color light separation optical system that separates light source light into three colors of light. Further, the projection optical device 213 includes a combining optical system that generates image light representing a color image by combining three color image lights. As for the configuration of such an optical system, various general projector optical system configurations can be used.

  The imaging device 22 images the projection surface (projected image F0) of the screen Sc under the control of the control device 23. The imaging device 22 is constituted by, for example, a CCD camera including an area sensor using a CCD (Charge Coupled Device) as an imaging device, and outputs an electrical signal corresponding to the captured image to the control device 23.

The control device 23 controls the entire image correction device 2. Hereinafter, the control of the liquid crystal light valve 212 in the control device 23 will be mainly described, and the other control structures will be omitted. The control device 23 causes the liquid crystal light valve 212 to form predetermined image light in accordance with the image signal input from the image output device 4. The control device 23 includes an interface unit 231, a frame memory 232, a shadow area recognition unit 233, and a liquid crystal panel drive control unit 234.
The interface unit 231 receives an image signal output from the image output device 4, converts the image signal into an image signal that can be processed in the control device 23, and outputs the image signal. The image signal (digital image signal) output from the interface unit 231 is temporarily recorded in the frame memory 232.

The shadow area recognition unit 233 recognizes the area (shadow area) of the shadow Sh generated in the projection image F0 based on the image captured by the imaging device 22. As shown in FIG. 2, the shadow area recognition unit 233 includes a projection image luminance value calculation unit 233A and a shadow area determination unit 233B.
The projection image luminance value calculation unit 233A recognizes the projection image F0 based on the image captured by the imaging device 22, and sets the luminance value of the entire area of the projection image F0 in units of pixels and R, G, Calculation is performed for each pixel of B. The projection image luminance value calculation unit 233A outputs a predetermined signal corresponding to information in which each calculated luminance value is associated with each pixel position to the shadow area determination unit 233B.
The shadow area determination unit 233B compares each luminance value in the projection image F0 calculated by the projection image luminance value calculation unit 233A with a predetermined first threshold value. Further, the shadow area determination unit 233B sets a predetermined flag (shadow part flag) at the pixel position where the luminance value is determined to be equal to or less than the first threshold value. Then, the shadow area determination unit 233B determines that the area where the pixel positions where the shadow flag is set is gathered is a shadow area generated in the projection image F0. The shadow area determination unit 233B outputs a signal corresponding to the determined shadow area to the liquid crystal panel drive control unit 234.

  The liquid crystal panel drive control unit 234 appropriately reads digital image signals output from the interface unit 231 and sequentially stored in the frame memory 232, and performs predetermined processing on the read digital image signals. Examples of the predetermined processing include image size adjustment processing such as enlargement / reduction, trapezoidal distortion correction processing, image quality adjustment processing, and gamma correction processing. In addition, the liquid crystal panel drive control unit 234 performs only the region corresponding to the shadow region (shadow corresponding region) based on the signal output from the shadow region recognition unit 233 in the image subjected to the predetermined processing. A drive signal for forming image light on which an image is formed is output to the liquid crystal light valve 212. As shown in FIG. 2, the liquid crystal panel drive control unit 234 includes a shadow corresponding area determination unit 234A and a display control unit 234B.

The shadow corresponding area determination unit 234A receives the signal output from the shadow area recognition unit 233, and recognizes the shadow area in the projection image F0. The shadow corresponding area determination unit 234A determines an area (shadow corresponding area) corresponding to the shadow area in the projection image F0 in the image (input image) on which the predetermined processing has been performed. The shadow part corresponding area determination unit 234A outputs a signal corresponding to the determined shadow part corresponding area to the display control unit 234B.
The display control unit 234B masks (displays in black) an area other than the shadow corresponding area determined by the shadow corresponding area determination unit 234A on the image on which the predetermined processing has been performed. A drive signal for forming image light for forming an image only inside is output to the liquid crystal light valve 212.

[1-3. Operation of image correction system]
Next, an image correction method in the image correction system 1 described above will be described with reference to the drawings. In the following, an example in which the shielding object C is interposed between the image projection device 3 and the screen Sc and a shadow Sh0 is generated in the projection image F0 will be described.
FIG. 3 is a flowchart for explaining the image correction method.
4 to 7 are diagrams for explaining the image correction method.
First, the control device 23 drives and controls the imaging device 22 to image the projection surface (projected image F0) of the screen Sc (step S1: imaging step). The imaging device 22 outputs an electrical signal corresponding to the captured image to the control device 23.
After step S1, the projection image luminance value calculation unit 233A recognizes the projection image F0 (FIG. 4) based on the image captured by the imaging device 22, and calculates the luminance value of the entire area of the projection image F0. Calculation is performed in units of pixels and for each of R, G, and B pixels (step S2: luminance value calculation step). The projection image luminance value calculation unit 233A outputs a predetermined signal corresponding to information in which each calculated luminance value is associated with each pixel position to the shadow area determination unit 233B.

After step S2, the shadow area determination unit 233B compares each luminance value in the projection image F0 calculated by the projection image luminance value calculation unit 233A with a predetermined first threshold (step S3: comparison step). .
Specifically, the shadow area determination unit 233B first compares the red luminance value at a predetermined pixel position in the projection image F0 with the red threshold value which is the first threshold value, and the red luminance value is determined. It is determined whether it is below the red threshold (step S3A).
In step S3A, when the shadow area determination unit 233B determines “N”, that is, when it is determined that the red luminance value at the predetermined pixel position is larger than the red threshold, the predetermined pixel position The comparison between the luminance value at 1 and the first threshold value is terminated.

On the other hand, when the shadow area determination unit 233B determines “Y” in step S3A, that is, when it is determined that the red luminance value at the predetermined pixel position is equal to or less than the red threshold value, the predetermined area is determined. The green luminance value at the pixel position is compared with the green threshold value which is the first threshold value, and it is determined whether or not the green luminance value is equal to or less than the green threshold value (step S3B).
In step S3B, if the shadow area determination unit 233B determines “N”, that is, determines that the green luminance value at the predetermined pixel position is greater than the green threshold value, the predetermined region The comparison between the luminance value at the pixel position and the first threshold is finished.

On the other hand, when the shadow area determination unit 233B determines “Y” in step S3B, that is, when it is determined that the green luminance value at the predetermined pixel position is equal to or less than the green threshold value, A blue luminance value at a predetermined pixel position is compared with a blue threshold value which is a first threshold value, and it is determined whether or not the blue luminance value is equal to or less than the blue threshold value (step S3C).
In step S3C, when the shadow area determination unit 233B determines “N”, that is, when it is determined that the blue luminance value at the predetermined pixel position is larger than the blue threshold value, the predetermined area is determined. The comparison between the luminance value at the pixel position and the first threshold is finished.

On the other hand, in step S3C, when the shadow area determination unit 233B determines “Y”, that is, when it is determined that the blue luminance value at the predetermined pixel position is equal to or less than the blue threshold value, A shadow flag is set at a predetermined pixel position (step S4).
After step S4, the shadow area determination unit 233B performs the above steps S3 and S4 over the entire area of the projection image F0 (FIG. 4), that is, at all pixel positions of the projection image F0. Is determined (step S5).
In step S5, when the shadow area determining unit 233B determines “N”, that is, when it is determined that steps S3 and S4 are not performed at all pixel positions of the projection image F0, the predetermined pixel is set. The position is changed to another pixel position, and steps S3 and S4 described above are performed.

In steps S3 to S5 described above, for example, the following method can be employed.
As shown in FIGS. 4 and 5, the shadow area determination unit 233B uses each luminance value on the predetermined horizontal scanning line H0 in the horizontal scanning interval H1 in the projection image F0 and the first threshold value St1 (red threshold value, And a shadow flag is set at a pixel position having a luminance value equal to or lower than the first threshold value St1. Then, the predetermined horizontal scanning line H0 is changed to another horizontal scanning line, and the above-described processing is sequentially performed.

  In step S5, when the shadow area determination unit 233B determines “Y”, that is, when it is determined that steps S3 and S4 are performed at all pixel positions of the projection image F0, in step S4 described above, The pixel position where the shadow flag is raised is recognized, and the area where the pixel positions where the shadow flag is raised is determined as the shadow area Sh0 (FIGS. 4 and 5) generated in the projection image F0 (step S6). : Shadow area determination step). The shadow area determination unit 233B outputs a signal corresponding to the determined shadow area Sh0 to the shadow corresponding area determination unit 234A.

  After step S6, the shadow corresponding area determination unit 234A receives the signal output from the shadow area determination unit 233B and recognizes the shadow area Sh0 in the projection image F0. Then, as illustrated in FIG. 6, the shadow corresponding area determination unit 234A reads the shadow corresponding to the shadow area Sh0 in the projection image F0 in the input image F1 read from the frame memory 232 and subjected to the predetermined processing. The part corresponding area Sh1 is determined (step S7: shadow corresponding area determining step). The shadow part corresponding area determination unit 234A outputs a signal corresponding to the determined shadow part corresponding area Sh1 to the display control unit 234B.

After step S7, as shown in FIG. 7, the display control unit 234B masks (displays in black) the area F1A other than the shadow corresponding area Sh1 with respect to the input image F1, and displays the image only in the shadow corresponding area Sh1. A drive signal for forming the image light FR on which Sh1A is formed is output to the liquid crystal light valve 212. Then, the liquid crystal light valve 212 modulates the light beam emitted from the light source device 211 in accordance with the drive signal output from the display control unit 234B to form the image light FR (step S8: image light forming step).
After step S8, the image light FR formed by the liquid crystal light valve 212 is enlarged and projected by the projection optical device 213, and is superimposed on the projection image F0 on the screen Sc. Then, the image Sh1A (FIG. 7) of the image light FR projected from the image correction device 2 is displayed in the shadow area Sh0 (FIG. 4) generated in the projection image F0 on the screen Sc, and the projection image F0. Correction for eliminating the shadow Sh generated inside is performed (step S9: image correction step).

  In the first embodiment described above, the image correction device 2 includes the correction device main body 21, the imaging device 22, and the control device 23. Therefore, when the shielding object C is interposed between the image projection device 3 and the screen Sc and a shadow Sh is generated in the projection image F0 projected from the image projection device 3 and formed on the screen Sc, the image correction device. 2, based on the image captured by the imaging device 22, the control device 23 can determine the shadow area Sh <b> 0 in the projection image F <b> 0 according to the luminance value at each pixel position in the projection image F <b> 0. Also, the control device 23 masks (displays in black) the region F1A other than the shadow corresponding region Sh1 corresponding to the shadow region Sh0 of the projection image F0 in the input image F1 acquired from the image output device 4, thereby corresponding to the shadow. The image light FR in which the image Sh1A is formed only in the region Sh1 is formed on the liquid crystal light valve 212 of the correction apparatus main body 21. For this reason, the image light FR is superimposed on the projection image F0 on the screen Sc from the projection optical device 213 of the correction device main body 21, thereby forming an image Sh1A that is originally projected on the shadow Sh portion of the projection image F0. The shadow Sh generated in the projected image F0 can be eliminated.

In addition, the shadow area determination unit 233B of the control device 23 compares the luminance value of each pixel position in the projection image F0 calculated by the projection image luminance value calculation unit 233A with the first threshold value St1. Since the area where pixel positions having luminance values equal to or smaller than the threshold value St1 are determined as the shadow area Sh0, the shadow area Sh0 can be easily and quickly determined.
Here, since the projection image luminance value calculation unit 233A calculates the luminance value at each pixel position in the entire region of the projection image F0, the shadow region determination unit 233B determines the shadow region Sh0 in the projection image F0 as a pixel unit. Therefore, the shadow area Sh0 can be accurately determined. For this reason, the process which eliminates the shadow Sh which generate | occur | produces in the projection image F0 can be implemented correctly, and it can be set as a projection image without a sense of incongruity. Further, since the projection image luminance value calculation unit 233A calculates the luminance value of each pixel position in the entire region of the projection image F0 for each of R, G, and B pixels, the shadow region determination unit 233B By determining the area where the pixel positions where the luminance values of all G and B are equal to or less than the first threshold value St1 are determined as the shadow area Sh0, the shadow area Sh0 can be determined more accurately.

  Further, the display control unit 234B of the control device 23 masks (displays in black) the area F1A other than the shadow corresponding area Sh1 in the input image F1, and generates the image light FR that forms the image Sh1A only in the shadow corresponding area Sh1. Since the liquid crystal light valve 212 is formed, the image Sh1A and the image displayed in the area other than the shadow area Sh0 in the projection image F0 do not overlap with each other, and the luminance values of the shadow area Sh0 and other areas are extremely small. As in the case where there is no change and the image projection apparatus 3 projects without the shielding object C interposed, it is possible to obtain a better projected image without a sense of incongruity.

[2. Second Embodiment]
Next, 2nd Embodiment of this invention is described based on drawing.
In the following description, the same structure and the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted or simplified.
[2-1. Configuration of image correction system and image correction apparatus]
FIG. 8 is a block diagram showing the configuration of the image correction system 1 ′ and the image correction apparatus 2 ′ in the second embodiment.
In the first embodiment, the control device 23 of the image correction device 2 does not consider the region even if there is an originally dark region of the projection image F0, and the shadow portion of the projection image F0. The region Sh0 is determined, and image light is formed on the liquid crystal light valve 212.
On the other hand, in the present embodiment, the control device 23 ′ of the image correction device 2 ′ includes a dark region recognition unit 235 that recognizes an originally dark region formed in the projection image F0, and the dark region recognition unit 235 recognizes it. The liquid crystal light valve 212 is caused to form predetermined image light in consideration of the region thus formed. The configuration other than the control device 23 ′ is the same as that of the first embodiment.

The dark area recognition unit 235 obtains an image (input image) read from the frame memory 232 by the liquid crystal panel drive control unit 234 and subjected to the predetermined processing, and is originally dark in the input image (dark area). Recognize The dark area recognition unit 235 includes an input image luminance value calculation unit 235A and a dark area determination unit 235B.
The input image luminance value calculation unit 235A acquires the input image from the liquid crystal panel drive control unit 234, and calculates the luminance value of the entire area of the input image for each pixel and for each pixel of R, G, and B. To do. The input image luminance value calculation unit 235A outputs a predetermined signal corresponding to information in which each calculated luminance value is associated with each pixel position to the dark region determination unit 235B.
The dark area determination unit 235B compares each luminance value in the input image calculated by the input image luminance value calculation unit 235A with a predetermined second threshold value. Further, the dark area determination unit 235B sets a predetermined flag (dark area flag) at the pixel position where the luminance value is determined to be equal to or less than the second threshold value. Then, the dark area determination unit 235B determines that the area where the pixel positions set with the dark area flag are gathered is an originally dark area in the input image. The dark area determination unit 235B outputs a signal corresponding to the determined dark area to the liquid crystal panel drive control unit 234.

  In the present embodiment, the shadow corresponding area determination unit 234A that configures the liquid crystal panel drive control unit 234 performs projection based on the signal output from the shadow area recognition unit 233 as described in the first embodiment. The shadow area in the image F0 is recognized, and the shadow area corresponding to the shadow area of the projection image F0 in the input image is determined. The shadow corresponding area determination unit 234A receives the signal output from the dark area determination unit 235B and recognizes the dark area in the input image. Then, the shadow corresponding area determination unit 234A corrects the shadow corresponding area by excluding the recognized dark area from the determined shadow corresponding area.

[2-2. Operation of image correction system]
Next, an image correction method in the above-described image correction system 1 ′ will be described with reference to the drawings. In the following description, as in the first embodiment, a case where a shielding object C is interposed between the image projection device 3 and the screen Sc and a shadow ShA is generated in the projection image F0 will be described as an example. To do.
FIG. 9 is a flowchart illustrating an image correction method according to the second embodiment.
10 to 13 are diagrams for explaining the image correction method.
First, as in the first embodiment, the control device 23 ′ captures the projection image F0 (step S1), calculates a luminance value (step S2), and compares the luminance value with the first threshold value St1 (step S3). ), Setting a shadow flag (step S4), determining whether or not the luminance value has been calculated at all pixel positions of the projection image F0 (step S5), determining the shadow area Sh0 (step S6), and handling shadows The determination of the area Sh1 is performed (step S7).
For example, as shown in FIG. 10, unlike the shadow ShA due to the presence of the shielding object C in the projection image F0, the luminance value is originally small (the luminance value equal to or lower than the first threshold value St1 described in the first embodiment). When the area DA is formed, the control device 23 ′ determines the area including the area DA as the shadow area Sh0 in addition to the shadow ShA by the steps S1 to S7. The shadow corresponding area Sh1 (FIG. 12) corresponding to the shadow area Sh0 is determined. In the following process, the shadow corresponding area Sh1C corresponding to the shadow ShA excluding the area DA is determined.

First, as shown in FIG. 11, the input image luminance value calculation unit 235A acquires the input image F1 read from the frame memory 232 and subjected to the predetermined processing by the liquid crystal panel drive control unit 234 (step S11). ).
After step S11, the input image luminance value calculation unit 235A calculates the luminance value of the entire area of the acquired input image F1 for each pixel and for each of R, G, and B pixels (step S12). . The input image luminance value calculation unit 235A outputs a predetermined signal corresponding to information in which each calculated luminance value is associated with each pixel position to the dark region determination unit 235B.

After step S12, the dark area determination unit 235B, in substantially the same manner as step S3 described in the first embodiment, determines each luminance value in the input image F1 calculated by the input image luminance value calculation unit 235A and a predetermined first value. The threshold value 2 is compared (step S13).
Specifically, the dark area determination unit 235B has the red luminance value and the second threshold value at a predetermined pixel position in the input image F1 in substantially the same manner as steps S3A to S3B described in the first embodiment. Comparison with the red threshold value (step S13A), comparison between the green luminance value at the predetermined pixel position and the green threshold value as the second threshold value (step S13B), blue luminance at the predetermined pixel position A comparison is made between the value and the blue threshold value which is the second threshold value (step S13C).
In Steps S13A to S13C, when it is determined that the red, green, and blue luminance values at the predetermined pixel position are equal to or less than a second threshold (red threshold, green threshold, blue threshold), a dark portion The area determination unit 235B sets a dark part flag at the predetermined pixel position (step S14).

After step S14, the dark area determination unit 235B has performed steps S13 and S14 over the entire area of the input image F1 (FIG. 11), that is, has been performed at all pixel positions of the input image F1. It is determined whether or not (step S15).
In step S15, if the dark area determination unit 235B determines “N”, that is, determines that steps S13 and S14 are not performed at all pixel positions of the input image F1, the predetermined pixel position is determined. Is changed to another pixel position, and Steps S13 and S14 described above are performed.
In steps S13 to S15 described above, the same method as in FIGS. 4 and 5 shown in the first embodiment can be adopted.
That is, the dark area determination unit 235B compares each luminance value on a predetermined horizontal scanning line during horizontal scanning in the input image F1 with the second threshold (red threshold, green threshold, blue threshold). A dark part flag is set at a pixel position having a luminance value equal to or lower than the second threshold value. Then, the predetermined horizontal scanning line is changed to another horizontal scanning line, and the above-described processing is sequentially performed.

  In step S15, if the dark area determination unit 235B determines “Y”, that is, if it is determined that steps S13 and S14 have been performed at all pixel positions of the input image F1, the dark area is determined in step S14 described above. The pixel position where the flag is raised is recognized, and the area where the pixel positions where the dark flag is raised is determined as a dark area DA1 (FIG. 11) which is an originally dark area in the input image F1 (step S16). The dark area determination unit 235B outputs a signal corresponding to the determined dark area DA1 to the shadow corresponding area determination unit 234A.

  After step S16, the shadow corresponding area determination unit 234A receives the signal output from the dark area determination unit 235B and recognizes the dark area DA1 in the input image F1. Then, as shown in FIG. 12, the shadow corresponding area determination unit 234A determines the shadow corresponding area Sh1C by excluding the dark area DA1 from the shadow corresponding area Sh1 determined in step S7 (step S17). The shadow part corresponding area determination unit 234A outputs a signal corresponding to the determined shadow part corresponding area Sh1C to the display control unit 234B.

After step S17, as shown in FIG. 13, the display control unit 234B displays an area F1A other than the shadow corresponding area Sh1C for the input image F1 in substantially the same manner as step S8 described in the first embodiment. The liquid crystal light valve 212 outputs a drive signal for masking (black display) to form the image light FR in which the image Sh1A is formed only in the shadow portion corresponding region Sh1C. Then, the liquid crystal light valve 212 modulates the light beam emitted from the light source device 211 according to the drive signal output from the display control unit 234B to form the image light FR (step S18).
After step S18, similarly to step S9 described in the first embodiment, the image light FR formed by the liquid crystal light valve 212 is enlarged and projected by the projection optical device 213, and the projected image F0 on the screen Sc is displayed. Superimposed. Then, the image Sh1A (FIG. 13) of the image light FR projected from the image correction device 2 ′ is displayed only on the portion of the shadow ShA (FIG. 10) generated in the projection image F0 on the screen Sc, and the projection image F0. Correction is performed to eliminate the shadow ShA portion generated inside (step S19).

  In the second embodiment described above, as compared to the first embodiment, the control device 23 ′ of the image correction device 2 ′ includes a dark area recognition unit 235 including an input image luminance value calculation unit 235A and a dark area determination unit 235B. Even if the shadow area determination unit 233B determines the area including the area DA that is originally dark in addition to the shadow ShA in the projection image F0 as the shadow area Sh0, the shadow area recognition unit 235 and The shadow corresponding area Sh1C excluding the dark area DA1 originally darkly formed can be determined by the shadow corresponding area determining section 234A. For this reason, the image Sh1A is not projected from the image correction apparatus 2 ′ to the originally dark area DA in the projection image F0, and the area DA can be displayed dark with the original luminance value. It is possible to display the image Sh1A only in the shadow ShA portion that occurs in FIG.

Further, the dark area determination unit 235B compares the luminance value of each pixel position in the input image F1 calculated by the input image luminance value calculation unit 235A with the second threshold value, and the luminance value equal to or lower than the second threshold value Since the area where the pixel positions are gathered is determined as the dark area DA1, the dark area DA1 can be determined easily and quickly.
Here, since the input image luminance value calculation unit 235A calculates the luminance value at each pixel position in the entire area of the input image F1, the dark area determination unit 235B determines the dark area DA1 in the input image F1 in units of pixels. Thus, the dark area DA1 can be accurately determined. For this reason, the area DA in the projection image F0 can be accurately displayed darkly with the original luminance value. Further, since the input image luminance value calculation unit 235A calculates the luminance value at each pixel position in the entire region of the input image F1 for each of R, G, and B pixels, the dark region determination unit 235B , B can determine the dark area DA1 more accurately by determining as the dark area DA1 the area where the pixel positions where all the luminance values are equal to or less than the second threshold value are determined.

[3. Third Embodiment]
Next, 3rd Embodiment of this invention is described based on drawing.
In the following description, the same structure and the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted or simplified.
[3-1. Configuration of image correction system and image correction apparatus]
FIG. 14 is a block diagram illustrating configurations of an image correction system 1 ″ and an image correction device 2 ″ according to the third embodiment.
In the first embodiment, the control device 23 of the image correction device 2 has a configuration corresponding to the case where the shielding object C is stationary, that is, the shadow generated in the projection image F0 is stationary.
On the other hand, in the present embodiment, the control device 23 ″ of the image correction device 2 ″ moves the shadow C in order to cope with the movement of the shielding object C, that is, the shadow generated in the projection image F0. A configuration in which a superimposition area determination unit 233C, a shadow area correction unit 233D, and an input image luminance value calculation unit 235A described in the second embodiment are added to the partial area recognition unit 233 ″, and a shadow area information storage unit 236 is provided. It is said. The configuration other than the control device 23 ″ is the same as that of the first embodiment.

The input image luminance value calculation unit 235A is the same as that in the second embodiment, acquires an input image from the liquid crystal panel drive control unit 234, and sets the luminance value of the entire area of the input image in units of pixels. Calculation is performed for each of R, G, and B pixels. The input image luminance value calculation unit 235A outputs a predetermined signal corresponding to information in which each calculated luminance value is associated with each pixel position to the superimposition region determination unit 233C.
The superimposition region determination unit 233C determines a predetermined value for each luminance value in the projection image F0 calculated by the projection image luminance value calculation unit 233A and the third threshold value (each luminance value calculated by the input image luminance value calculation unit 235A). Compared with the value added). In addition, the superimposition region determination unit 233C sets a predetermined flag (superimposition flag) at the pixel position where the luminance value is determined to be greater than or equal to the third threshold value. Then, the superimposition area determination unit 233C determines that the area where the pixel positions for which the superimposition flag is set is gathered, an image included in the image light projected from the image correction device 2 '' according to the conventional shadow area, It is determined as a superimposition region in which the luminance value is increased by superimposing the projected image generated by moving the shadow region. The overlapping area determination unit 233C outputs a signal corresponding to the determined overlapping area to the shadow area correction unit 233D.

The shadow area correction unit 233D reads the shadow area information stored in the shadow area information storage unit 236, and recognizes the previous shadow area based on the shadow area information. Further, the shadow area correction unit 233D determines a correction area obtained by excluding the overlapping area determined by the overlapping area determination unit 233C from the recognized previous shadow area. Then, the shadow area correction unit 233D adds the determined correction area and the shadow area determined by the shadow area determination unit 233B to correct the shadow area. The shadow area correction unit 233D outputs a signal corresponding to the corrected shadow area to the shadow corresponding area determination unit 234A and the shadow area information storage unit 236.
The shadow area information storage unit 236 receives the signal output from the shadow area correction unit 233D and stores the shadow area information regarding the corrected shadow area. The shadow area information storage unit 236 appropriately updates the shadow area information according to the output of the signal from the shadow area correction unit 233D.

[3-2. Operation of image correction system]
Next, an image correction method in the above-described image correction system 1 '' will be described with reference to the drawings. In the following, similarly to the first embodiment, the shielding object C is interposed between the image projection device 3 and the screen Sc, and a shadow is generated in the projection image F0. It is assumed that the process of eliminating is performed. Moreover, below, the case where the shield C moves and the shadow moves will be described as an example.
FIG. 15 is a flowchart illustrating an image correction method according to the third embodiment.
16 to 19 are diagrams for explaining the image correction method.
First, as in the first embodiment, the control device 23 ″ captures the projection image F0 (step S1), calculates a luminance value (step S2), and compares the luminance value with the first threshold value St1 (step). S3), setting a shadow flag (step S4), determining whether or not the luminance value has been calculated at all pixel positions of the projection image F0 (step S5), and determining the shadow area Sh0 (step S6). .
For example, as shown in FIG. 16, when the shielding object C moves and the shadow area moves from the shadow area Sh01 to the shadow area Sh02 in the projection image F0 (moves in the direction of arrow R in FIG. 16). The image Sh1A is displayed in the shadow area Sh01 by the process of eliminating the previous shadow area Sh01. Therefore, in the steps S1 to S6, as shown in FIG. 17, the luminance values of only the area that does not overlap with the shadow area Sh01 in the shadow area Sh02 are smaller than the first threshold value St1. The area is determined as the shadow area Sh0. Then, after Steps S1 to S6, when Steps S7 to S9 are performed as in the first embodiment, the image Sh1A is displayed in the shadow area Sh0 portion of the moved shadow area Sh02, Shadows remain in the area Sh03 where the shadow areas Sh01 and Sh02 overlap. In the following steps, the shadow area is corrected by including the area Sh03 in the shadow area Sh0, and the shadow area Sh02 is determined.

  First, the input image luminance value calculation unit 235A obtains the input image F1 (step S21) as in steps S11 and S12 of the second embodiment, and sets the luminance values of the entire area of the input image F1 in units of pixels. And it calculates for every pixel of R, G, B, respectively (step S22). The input image luminance value calculation unit 235A outputs a predetermined signal corresponding to information in which each calculated luminance value is associated with each pixel position to the superimposition region determination unit 233C.

After step S22, the overlapping area determination unit 233C generates a third threshold value St3 (FIG. 17) by adding a predetermined value to each luminance value calculated by the input image luminance value calculation unit 235A. In addition, the superimposition area determination unit 233C generates the brightness values of the projection image F0 calculated by the projection image brightness value calculation unit 233A in step S2 and the generated values in substantially the same manner as step S3 described in the first embodiment. The third threshold value is compared (step S23).
Specifically, the superimposition region determination unit 233C is substantially the same as Steps S3A to S3B described in the first embodiment, and the red luminance value at a predetermined pixel position in the projection image F0 and the predetermined value in the input image F1. Comparison with the red threshold value which is the third threshold value St3 generated based on the luminance value at the pixel position corresponding to the pixel position (step S23A), and the green luminance value at the predetermined pixel position in the projection image F0 Comparison with the green threshold value which is the third threshold value St3 generated based on the luminance value of the pixel position corresponding to the predetermined pixel position in the input image F1 (step S23B), at the predetermined pixel position in the projection image F0 A comparison is made between the blue brightness value of the first threshold value and the blue threshold value which is the third threshold value St3 generated based on the brightness value of the pixel position corresponding to the predetermined pixel position in the input image F1 (step Flop S23C) to implement.
In steps S23A to S23C, it is determined that the red, green, and blue luminance values at the predetermined pixel position in the projection image F0 are equal to or greater than a third threshold value St3 (red threshold value, green threshold value, blue threshold value). In such a case, the overlapping area determination unit 233C sets an overlapping flag at the predetermined pixel position in the projection image F0 (step S24).

After step S24, the overlapping area determination unit 233C determines whether or not the above steps S23 and S24 have been performed over the entire area of the projection image F0, that is, whether or not all of the pixel positions of the projection image F0 have been performed. (Step S25).
In step S25, when the overlapping region determination unit 233C determines “N”, that is, when it is determined that steps S23 and S24 are not performed at all pixel positions of the projection image F0, the superimposition region determination unit 233C The predetermined pixel position is changed to another pixel position, and steps S23 and S24 described above are performed.
In steps S23 to S25 described above, as shown in FIG. 17, the same methods as in steps S3 to S5 described in the first embodiment and FIGS. 4 and 5 can be employed.

  In step S25, when the overlap region determination unit 233C determines “Y”, that is, when it is determined that steps S23 and S24 are performed at all pixel positions of the projection image F0, the overlap is determined in step S24 described above. An image Sh1A included in the image light FR projected from the image correction device 2 '' according to the previous shadow area Sh01 is obtained by recognizing the pixel position where the flag is raised and collecting the pixel positions where the superimposition flag is raised. Then, it is determined as the superimposed region OL (FIG. 16, FIG. 17) in which the brightness value is increased by superimposing the projected image F0 generated by the movement of the previous shadow region Sh01 (step S26). The overlapping area determination unit 233C outputs a signal corresponding to the determined overlapping area OL to the shadow area correction unit 233D.

  After step S26, the shadow area correction unit 233D receives the signal output from the overlapping area determination unit 233C and recognizes the overlapping area OL in the projection image F0. Further, the shadow area correction unit 233D reads the shadow area information stored in the shadow area information storage unit 236, and recognizes the previous shadow area Sh01 based on the shadow area information. Further, the shadow area correction unit 233D determines a correction area Sh03 (FIGS. 16 and 17) obtained by removing the superimposed area OL from the recognized previous shadow area Sh01. Then, the shadow area correction unit 233D determines the current shadow area Sh02 by adding the determined correction area Sh03 and the shadow area Sh0 determined in Step S6 described above (Step S27). The shadow area correction unit 233D outputs a signal corresponding to the determined current shadow area Sh02 to the shadow corresponding area determination unit 234A and the shadow area information storage unit 236.

After step S27, the shadow area information storage unit 236 changes the stored shadow area Sh01 according to the signal output from the shadow area correction unit 233D and stores the shadow area Sh02 (step S27). S28).
After step S28, the shadow corresponding area determination unit 234A receives the signal output from the shadow area correction unit 233D, and recognizes the current shadow area Sh02 in the projection image F0. Then, as shown in FIG. 18, the shadow corresponding area determination unit 234A reads from the frame memory 232 and performs the predetermined processing, similarly to step S7 described in the first embodiment. The shadow corresponding area Sh12 corresponding to the shadow area Sh02 in the projection image F0 is determined (step S29). The shadow part corresponding area determination unit 234A outputs a signal corresponding to the determined shadow part corresponding area Sh12 to the display control unit 234B.

After step S29, the display control unit 234B causes the shadow corresponding region to change from the previous shadow corresponding region Sh1 (FIG. 19) to the current shadow corresponding region in accordance with the signal output from the shadow corresponding region determining unit 234A. It recognizes that it changed to Sh12. Then, similarly to step S8 described in the first embodiment, the display control unit 234B masks the area F1A other than the shadow corresponding area Sh12 (black display) on the input image F1, as shown in FIG. ) And outputs a drive signal to the liquid crystal light valve 212 to form the image light FR in which the image Sh12A is formed only in the shadow corresponding region Sh12. Then, the liquid crystal light valve 212 modulates the light beam emitted from the light source device 211 in accordance with the drive signal output from the display control unit 234B to form the image light FR (step S30).
After step S30, similarly to step S9 described in the first embodiment, the image light FR formed by the liquid crystal light valve 212 is enlarged and projected by the projection optical device 213, and is projected onto the projected image F0 on the screen Sc. Superimposed. Then, the image Sh12A (FIG. 19) of the image light FR projected from the image correction device 2 ″ is displayed on the portion of the current shadow Sh02 (FIG. 16) generated in the projected image F0 on the screen Sc, and projected. Correction for eliminating the current shadow Sh02 portion generated in the image F0 is performed (step S31).

  In the third embodiment described above, as compared with the first embodiment, the control device 23 ″ of the image correction device 2 ″ has the input image luminance value calculation unit 235A, the overlapping region determination unit 233C, and the shadow region correction. Part 233D and a shadow area information storage part 236. For this reason, the image Sh1A included in the image light FR projected from the image correction device 2 '' according to the previous shadow area Sh01 by the input image luminance value calculation section 235A and the overlapping area determination section 233C, and the previous shadow section It is possible to determine the superimposed region OL in which the brightness value is increased by superimposing the projected image F0 generated by the movement of the region Sh01. Further, the shadow area correction unit 233D can determine the correction area Sh03 by excluding the overlap area OL from the previous shadow area Sh01, and the correction area Sh03 and a set of pixel positions having luminance values equal to or less than the first threshold value St1. The current shadow area Sh02 can be determined by adding the shadow area Sh0. Therefore, even when the shadow object C moves and the shadow area moves from the shadow area Sh01 to the shadow area Sh02 in the projection image F0, the current shadow area Sh02 is accurately determined and the original shadow area Sh02 is determined. The process of eliminating the shadow area Sh02 can be performed satisfactorily.

In addition, the overlapping area determination unit 233C compares the luminance value of each pixel position in the projection image F0 with the third threshold value St3 generated based on the luminance value of each pixel position in the input image, and the third threshold value Since the area where the pixel positions having luminance values equal to or greater than St3 are determined as the overlapping area OL, the overlapping area OL can be easily and quickly determined.
Here, the projection image luminance value calculation unit 233A calculates the luminance value at each pixel position in the entire region of the projection image F0, and the input image luminance value calculation unit 235A calculates the luminance value at each pixel position in the entire region of the input image F1. Since the calculation is performed, the overlapping area determination unit 233C determines the overlapping area OL in the projection image F0 in units of pixels, and can accurately determine the overlapping area OL. Therefore, the current shadow area Sh02 can be determined more accurately. In addition, since the projection image luminance value calculation unit 233A and the input image luminance value calculation unit 235A calculate the luminance value of each pixel position in the entire region for each of R, G, and B pixels, the superimposed region determination unit 233C , R, G, and B can be more accurately determined by determining a region where pixel positions having luminance values equal to or greater than the third threshold value St3 as the overlapping region OL.

It should be noted that the present invention is not limited to the above-described embodiments, and modifications, improvements, and the like within the scope that can achieve the object of the present invention are included in the present invention.
In each of the embodiments, the display control unit 234B of the image correction device 2, 2 ′, 2 ″ masks (displays in black) the area F1A other than the shadow corresponding areas Sh1, Sh1C, Sh12, and displays the shadow corresponding area Sh1. , Sh1C and Sh12 are formed with the image light FR in which the images Sh1A and Sh12A are formed in the liquid crystal light valve 212, but the present invention is not limited to this.
For example, any image light may be formed in the liquid crystal light valve 212 as long as the luminance values of the shadow corresponding regions Sh1, Sh1C, Sh12 are higher than the luminance values of the other regions F1A.

In each of the above embodiments, the projection image luminance value calculation unit 233A and the input image luminance value calculation unit 235A calculate the luminance value at each pixel position in the entire region in the projection image F0 and the input image F1, but this is not limitative. Absent. For example, a configuration in which luminance values are calculated at a plurality of predetermined pixel positions in the entire region may be employed.
In the third embodiment, a configuration in which the input image luminance value calculation unit 235A is omitted may be employed. In other words, the third threshold value St3 may be set in advance, and the overlapping region OL may be determined using the set third threshold value St3.
In each of the above embodiments, the flow shown in FIGS. 3, 9, and 15 is not limited to the flow described in each of the above embodiments.
For example, in steps S3, S13, and S23, a configuration in which luminance values are not compared for each pixel of R, G, and B, but a configuration that uses an average value of luminance values of each pixel of R, G, and B is compared. It may be adopted.
In addition, for example, in the second embodiment, a configuration in which the determination of the dark area DA (steps S11 to S16) is performed before the determination of the shadow area Sh0 (steps S1 to S7) may be adopted.
Further, for example, in the third embodiment, a configuration may be adopted in which the determination of the overlapping region OL (Steps S21 to S26) is performed before the determination of the shadow region Sh0 (Steps S3 to S7).

In each of the above embodiments, the shadow area generated in the projection image F0 is determined by directly comparing the data of the projection image F0 captured by the imaging device 22 with the data of the input image F1 acquired from the image output device 4. By doing so, you may employ | adopt the structure implemented.
In each of the above embodiments, a transmissive liquid crystal panel (liquid crystal light valve 212) is employed as the light modulation device. However, the present invention is not limited to this, and a reflective liquid crystal panel may be employed. A mirror device (trademark of Texas Instruments) may be employed.

Although the best configuration for carrying out the present invention has been disclosed in the above description, the present invention is not limited to this. That is, the present invention has been illustrated and described primarily with respect to particular embodiments, but is not limited to the embodiments described above without departing from the scope and spirit of the present invention. Various modifications can be made by those skilled in the art in terms of materials, quantity, and other detailed configurations.
Therefore, the description limited to the shape, material, etc. disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such restrictions is included in this invention.

  The image correction apparatus according to the present invention corrects the projection image and displays a projection image without a shadow on the screen even when a shadow is generated on the projection image on the screen by the shielding object. The projector can be used as an image correction device that corrects a projected image projected from the projector to the screen.

1 is a diagram illustrating a schematic configuration of an image correction system according to a first embodiment. The block diagram which shows the structure of the image correction apparatus in the said embodiment. 6 is a flowchart for explaining an image correction method according to the embodiment. The figure for demonstrating the image correction method in the said embodiment. The figure for demonstrating the image correction method in the said embodiment. The figure for demonstrating the image correction method in the said embodiment. The figure for demonstrating the image correction method in the said embodiment. The block diagram which shows the structure of the image correction system and image correction apparatus in 2nd Embodiment. 6 is a flowchart for explaining an image correction method according to the embodiment. The figure for demonstrating the image correction method in the said embodiment. The figure for demonstrating the image correction method in the said embodiment. The figure for demonstrating the image correction method in the said embodiment. The figure for demonstrating the image correction method in the said embodiment. The block diagram which shows the structure of the image correction system and image correction apparatus in 3rd Embodiment. 6 is a flowchart for explaining an image correction method according to the embodiment. The figure for demonstrating the image correction method in the said embodiment. The figure for demonstrating the image correction method in the said embodiment. The figure for demonstrating the image correction method in the said embodiment. The figure for demonstrating the image correction method in the said embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Image correction system, 2, 2 ', 2' '... Image correction apparatus, 3 ... Image projection apparatus, 4 ... Image output apparatus, 21 ... Correction apparatus main body, 22 ... Imaging device 23, 23 ', 23' '... control device, 211 ... light source device, 212 ... liquid crystal light valve, 213 ... projection optical device, 233A ... projection image luminance value calculation , 233B ... shadow area determination unit, 233C ... superimposition area determination unit, 233D ... shadow area correction unit, 234A ... shadow area corresponding determination unit, 234B ... display control unit, 235A: input image luminance value calculation unit, 235B: dark area determination unit, DA1: dark area, 236: shadow area information storage, OL: overlap area, S1: imaging Step, S2 ... Luminance value calculating step, S3 ... Comparison step , S6 ... shadow area determination step, S7 ... shadow area corresponding determination step, S8 ... image light formation step, S9 ... image correction step, Sc ... screen, Sh0, Sh01, Sh02 ... shadow area, Sh03 ... correction area, Sh1, Sh1C, Sh12 ... shadow area corresponding area, St1, St3 ... threshold.

Claims (7)

An image correction apparatus for correcting a projected image projected on a screen,
A light modulation device that modulates a light beam emitted from a light source to form image light, and a projection optical device that enlarges and projects the formed image light toward the screen and superimposes it on the projection image. A correction device body, a control device that drives and controls the light modulation device to form predetermined image light on the light modulation device, and an imaging device that images the projection surface of the screen,
The controller is
A projection image luminance value calculation unit that calculates luminance values at a plurality of predetermined positions in the projection image based on an image captured by the imaging device;
Each brightness value in the projection image calculated by the projection image brightness value calculation unit is compared with a first threshold value, and a shadow area where the brightness value in the projection image is equal to or less than the first threshold value is determined. A shadow area determination unit;
A shadow-corresponding region determination unit that acquires an image signal corresponding to the projection image and determines a shadow-corresponding region corresponding to the shadow region in the input image based on the acquired image signal;
A display control unit that drives and controls the light modulation device and causes the light modulation device to form image light in which the luminance value of the shadow area corresponding to the input image is higher than the luminance value of other regions; An image correction apparatus characterized by the above. The image correction apparatus according to claim 1,
The control device includes an input image luminance value calculation unit that acquires an image signal corresponding to the projection image and calculates luminance values at a plurality of predetermined positions in the input image based on the acquired image signal; and the input image luminance A dark area determination unit that compares each luminance value in the input image calculated by the value calculation unit with a second threshold and determines a dark area in which the luminance value in the input image is equal to or less than the second threshold; Prepared,
The shadow correction area determination unit corrects the shadow corresponding area by excluding the dark area from the shadow corresponding area in the input image. The image correction apparatus according to claim 1 or 2,
The control device includes a shadow area information storage unit that stores shadow area information related to the previous shadow area, a brightness value in the projection image calculated by the projection image brightness value calculation unit, and a third value. A superimposition region determination unit that compares a threshold value and determines a superimposition region in which the luminance value in the projection image is equal to or greater than the third threshold value, and the shadow region information stored in the shadow region information storage unit A shadow region correction unit that corrects the shadow region by adding a correction region obtained by removing the superimposition region from the previous shadow region and the shadow region determined by the shadow region determination unit;
The shadow correction area determination unit determines a shadow corresponding area corresponding to the corrected shadow area in the input image. In the image correction device according to any one of claims 1 to 3,
The projection image luminance value calculation unit and the input image luminance value calculation unit calculate a luminance value for each pixel in the entire image area. In the image correction device according to any one of claims 1 to 4,
The image correction apparatus, wherein the display control unit causes the light modulation device to form image light that masks other areas other than the shadow corresponding area in the input image. An image correction method for correcting a projected image projected on a screen,
An imaging step of imaging the projection surface of the screen;
A luminance value calculating step of calculating each luminance value at a plurality of predetermined positions in the projection image based on the captured image;
A comparison step of comparing each brightness value in the calculated projection image with a first threshold value;
As a result of the comparison in the comparison step, a shadow area determination step for determining a shadow area in which the luminance value in the projection image is equal to or less than the first threshold value;
A shadow corresponding region determination step of acquiring an image signal corresponding to the projection image and determining a shadow corresponding region corresponding to the shadow region in the input image based on the acquired image signal;
An image light forming step of forming image light in which the luminance value of the shadow area in the input image is higher than the luminance value of other areas;
An image correction method comprising: an image correction step of enlarging and projecting the image light toward the screen and superimposing the image light on the projection image. A light modulation device that modulates a light beam emitted from a light source to form image light, a control device that acquires a predetermined image signal and forms image light based on the image signal in the light modulation device, and the light modulation device An image projection apparatus including a projection optical apparatus that enlarges and projects the image light formed on the screen toward the screen to form a predetermined projection image;
An image correction apparatus according to any one of claims 1 to 5,
An image correction system comprising: an image output device that outputs the same image signal to the image projection device and the image correction device.

Images