JP2004140845A - Projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform distortion correction of an image according to the shape of a projection plane and to correct distortion of a display image also for projection planes of a plane with irregularity and a curved surface in a projector. <P>SOLUTION: The projector to be disclosed is constituted by providing a video image input part 1 which inputs an original image, a projection plane acquisition part 3 which acquires the three-dimensional shape of the projection plane by calculating an azimuthal angle, a tilt angle and distance of the projection plane from normal vector of the projection plane, a video image correction part 2 which performs tilt correction and magnification/reduction correction to an inputted original image corresponding to the shape of the projection plane and a video image output part 4 which projects and outputs the corrected image. Thus, the distortion when it is projected from an optional direction to the projection plane can not only be corrected but the distortion of the display image can be corrected for the projection planes of the surface with irregularity and the curved surface. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to a projector device capable of correcting distortion of a projected image.

2. Description of the Related Art In a projector device that extracts an image generated on a liquid crystal panel or the like by transmission or reflection and projects the image on a projection surface (screen), the magnification of the image when projecting the image on the projection surface depends on each component. In order to make them uniform, it is necessary that the optical axis of the projector device intersects perpendicularly with the center of the projection plane. However, in such a case, in the front-projection type projector device, the projector device is disposed near the center in front of the projection surface, which hinders the audience from seeing the image on the projection surface. Further, even in a rear projection type projector device, it may be difficult to arrange the projector device at an ideal position due to space and the like. Therefore, it is necessary to arrange the projector device so that the optical axis of the projector device is oblique with respect to the projection plane. However, when the image is projected from an oblique direction, distortion occurs in the projected image. Will be.

On the other hand, conventionally, there has been known a method of obtaining an image with little distortion by performing some kind of correction. FIG. 13 shows an example of a video correction method in the related art (see Patent Document 1). In this conventional projector apparatus, a horizontally-long converted image as shown in FIG. 13B compressed in the vertical direction is generated from the original image shown in FIG. 13A, and a keystone (trapezoidal) distortion is generated. A corrected trapezoidal distortion image as shown in FIG. 13C is generated, and the image is projected obliquely upward from the front onto a vertical projection surface by the projector device, thereby distorting the image on the projection surface. Is corrected, and a display screen as shown in FIG. 13D is obtained.

JP-A-9-275538

However, in the conventional projector device shown in FIG. 13, since the processes of the landscape conversion and the trapezoidal distortion correction are performed, it is not possible to perform the distortion correction when projecting from upward, rightward, leftward, and downward directions. However, there is a problem that it is not possible to correct the distortion as in the case where the projection is performed from the lower right direction, the upper right direction, the lower left direction, and the upper left direction. Also, it is difficult to deal with distortion when the projection plane is not a plane only by the horizontal transformation and the trapezoidal distortion correction.

The present invention has been made in view of the above circumstances, and has as its object to provide a projector apparatus having a function of correcting distortion when the image is projected from an arbitrary direction onto a projection surface. Another object of the present invention is to provide a projector device having a function of correcting distortion when projected on a projection surface having irregularities or a curved surface.

In order to solve the above problem, the invention according to claim 1 includes a video input unit for inputting an original image, a projection plane acquisition unit for calculating a tilt angle and a distance of the projection plane from a normal vector of the projection plane, and Video correction means for performing distortion correction processing on an input original image in accordance with the shape of the projection surface using the tilt angle and the distance calculated by the projection plane acquisition means; and projecting and outputting the corrected image. And a distance between a reference plane, which is a plane on which an image to be photographed on a projection plane is displayed and is a reference plane, and the center of the projector. And a process of changing the image of the temporary reference plane passing through the intersection of the projector optical axis and the projection plane into an image of the projection plane using the distance and the inclination angle. It is characterized by:

The invention according to claim 2 is an image input means for inputting an original image, a projection plane obtaining means for calculating an azimuth, a tilt angle and a distance of the projection plane from a normal vector of the projection plane, and the projection plane. Using the azimuth angle, the inclination angle, and the distance calculated by the acquisition unit, a video correction unit that performs a distortion correction process on the input original image in accordance with the shape of the projection surface, and Video output means for projecting and outputting, wherein the distortion correction process rotates the original image according to the azimuth angle, changes the size according to the ratio of the distance to the focal length of the projector lens, and Tilt correction that changes the coordinates of the image on the surface according to the distance and the tilt angle, and enlargement / change that changes the coordinates of the original image according to the ratio of the distance from the center of the projector to the reference plane and the distance. With reduction correction It is characterized in Mukoto.

According to a third aspect of the present invention, there is provided the projector device according to the first or second aspect, wherein a focal length of a projector lens is calculated in accordance with a distance of the projection plane calculated by the projection plane obtaining means, and the image is displayed. A projection control unit for performing focus control in the output unit is provided.

According to a fourth aspect of the present invention, there is provided the projector according to the third aspect, wherein the tilt correction is performed according to the focal length calculated by the projection control means.

According to a fifth aspect of the present invention, a three-dimensional shape of the projection surface is calculated by calculating an azimuth angle, an inclination angle, and a distance of the projection surface from a video input means for inputting an original image and a normal vector of the projection surface. Projection plane acquisition means for acquiring, a virtual projection plane generation means for generating a virtual projection plane from the projection plane shape calculated by the projection plane acquisition means, and back projection simulation by perspective transformation processing of the input original image onto the virtual projection plane And a perspective transformation unit for calculating a corrected image by projecting the three-dimensional image obtained as described above, and a video output unit for projecting and outputting the corrected image.

According to the configuration of the present invention, the three-dimensional shape of the projection plane is obtained for correcting the distortion of the image of the projector device, and the correction parameters are controlled in accordance with the three-dimensional shape of the projection plane. Here, the three-dimensional shape of the projection surface refers to the distance and inclination of the projection surface from the projector device. In the present invention, the three-dimensional shape depends on the projection distance and the projection direction with respect to the projection surface from the projector device. Then, the distortion of the projected image is corrected. Further, the distortion of the projected image is further corrected by recognizing not only the distance and inclination of the projection surface but also the unevenness and the curved shape of the projection surface. Therefore, according to the present invention, it is possible to correct distortion when projected onto a projection surface from an arbitrary direction, and also to correct distortion when projected onto a projection surface having irregularities or a curved surface. is there.

ADVANTAGE OF THE INVENTION According to the projector apparatus of this invention, not only the distortion at the time of projecting from an arbitrary direction with respect to a projection surface can be corrected, but also the distortion of a display image with respect to the uneven projection surface or the curved projection surface. Can be corrected. This is because image distortion correction is performed according to the shape of the projection surface. Further, the focus of the projector device can be adjusted. This is because the distance of the projection plane is measured, and the focal length of the projector lens is controlled according to the distance. Further, the image distortion correction processing can be performed at high speed. This is because an approximate virtual projection plane corresponding to the shape of the projection plane is generated, and distortion of the image is corrected for the approximate virtual projection plane by a perspective transformation process. Further, the process of acquiring the shape of the projection plane can be performed using a general-purpose camera. This is because the shape of the projection plane can be calculated based on the principle of triangulation by taking an image of the pattern projected onto the projection plane with a camera. Further, the shape acquisition processing of the projection plane can be performed at high speed. This is because the projection plane shape can be calculated only by acquiring data from a device capable of controlling the position and direction of the projector device and thereby converting the previously stored shape data in the projection room. In addition, the size and weight of the projection plane shape acquisition device can be reduced. This involves simply attaching a marker in the projection room in advance, observing the marker from the projector device, calculating the position and direction of the projector device, and thereby converting the previously saved shape data in the projection room. This is because the projection plane shape can be calculated.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The description will be made specifically using an embodiment.

First Embodiment FIG. 1 is a block diagram showing a configuration of a projector device according to a first embodiment of the present invention, FIG. 2 is a flowchart showing a flow of a correction process in this embodiment, and FIG. And FIG. 4 is a diagram for explaining a process of inclination correction in this embodiment. As shown in FIG. 1, the projector device of this example is schematically configured by a video input unit 1, a video correction unit 2, a projection plane acquisition unit 3, and a video output unit 4. The video input unit 1 inputs an original image. The image correction unit 2 performs a process of correcting image distortion. The projection plane acquisition unit 3 acquires information on the three-dimensional shape of the projection plane. The video output unit 4 performs projection output of the video whose distortion has been corrected. It should be noted that a known three-dimensional shape measuring device can be used as the projection plane acquiring unit 3, but this device is well known to those skilled in the art and is not directly related to the main part of the present invention. The description of the detailed configuration is omitted.

Next, the operation of the projector device of this example will be described with reference to FIG. When an original image is input from the video input unit 1, the video correction unit 2 performs a video distortion correction process using information from the projection plane acquisition unit 3. At this time, the projection plane acquisition unit 3 determines the three-dimensional shape of the projection plane. The three-dimensional shape of an arbitrary projection plane can be represented by three parameters of azimuth, inclination, and distance. Here, the azimuth angle is an angle indicating which direction the projection surface is inclined with respect to the projector device (a rotation angle around an axis orthogonal to the optical axis in a vertical plane including the optical axis of the projector device). ). The tilt angle is an angle indicating how much the projection plane is tilted (a rotation angle around a horizontal axis orthogonal to the optical axis of the projector device). The distance is the distance from the center of the projector (refers to the center of the projector lens; hereinafter, omitted) to the center of projection. The projection plane acquisition unit 3 calculates three parameters of an azimuth angle, an inclination angle, and a distance of the measured projection plane shape.

Next, the flow of the correction process in the projector device of this example will be described with reference to FIG. At the start of the correction process, the projection plane acquisition unit 3 first calculates a normal vector of the projection plane (step S101). The normal vector of the projection plane is obtained by measuring the positions of at least three points on the projection plane. Next, the projection plane acquisition unit 3 obtains the azimuth and the inclination angle of the projection plane from the normal vector (step S102). When a normal vector (a, b, c) is obtained in a coordinate system in which the optical axis of the projector apparatus is the Z axis and the upper part is the Y axis, the azimuth is obtained as tan-1 (b / a). And the inclination angle is obtained as tan-1 (c / √ (a2 + b2)). Next, the projection plane acquisition unit 3 calculates the distance from the center of the projector to the center of the projection plane by calculating the intersection between the optical axis of the projector device and the projection plane (step S103).

Next, the image correction unit 2 performs a tilt correction process (step S104). 3 and 4 are cross-sectional views cut along a plane including the optical axis of the projector and the normal vector of the projection plane 109. The reference plane 112 is a plane serving as a reference from the projector apparatus 100, and is corrected to an image projected on the reference plane 112, and the image is projected on the projection plane 110. Here, the temporary reference plane 111 is defined as a plane that is parallel to the reference plane 112 and passes through the intersection of the projector optical axis and the projection plane 110. First, in FIG. 3, assuming that the distance from the projector apparatus 100 to the reference plane 112 is Z0 and the distance from the projector apparatus 100 to the provisional reference plane 111 is Z1, the y-axis value l0 of the reference plane is , The y-axis value of the corresponding point in the original image must be multiplied by z0 / z1, that is, y ″ = y · z0 / z1. This is a simple scaling calculation. , X-axis values.

Further, in FIG. 4, in order for the y-axis value l on the temporary reference plane 111 to be projected at the position of l on the projection plane 110, the y-axis value of the corresponding point in the original image is multiplied by tanφ / tanθ, that is, y "= y ・ tanφ / tanθ = y ・ z1 ・ cosα / (z1 + y ・ sinα). For the x-axis value, the length of the original image must be displayed at the position of the distance z3. Therefore, x ″ = x · z1 / (z1 + y · sinα).

From the above, in order to correct a certain image, (1) the image is rotated by the azimuth, (2) the image is scaled from the distance between the projector apparatus 100 and the reference plane 112 and the projection plane 110, and (3) the inclination angle of the projection plane 110. Correction corresponding to α is performed (x ′, y ′) = (k · x, k · cosα · y), k = z1 / (z1 + y · sinα). (4) The processing may be executed in the order of correcting the rotation of the image. As described above, according to the projector device of this example, even when the image is projected on the projection plane 110 from an arbitrary direction, it is possible to project an image with distortion corrected.

Second Embodiment FIG. 5 is a block diagram showing a configuration of a projector device according to a second embodiment of the present invention. As shown in FIG. 5, the projector device of this example is schematically configured by a video input unit 11, a video correction unit 12, a projection plane acquisition unit 13, a video output unit 14, and a projection control unit 15. . The video input unit 11, the video correction unit 12, and the projection plane acquisition unit 13 are the same as the video input unit 1, the video correction unit 2, and the projection plane acquisition unit 3 in the case of the first embodiment shown in FIG. . The video output unit 14 performs projection output based on the corrected video from the video correction unit 12, and adjusts the focus of the projector lens according to control from the projection control unit 15. The projection control unit 15 controls the focal length of the projector lens in the video output unit 14.

The basic configuration of the projector device of this example is almost the same as that of the first embodiment, except that a projection control unit 15 is provided to enable control of the focal length in the video output unit 14. . Hereinafter, the operation of the projector device of this example will be described with reference to FIG. When an original image is input from the video input unit 11, the video correction unit 12 performs a video distortion correction process using information from the projection plane acquisition unit 13. At this time, the projection plane acquisition unit 13 measures the three-dimensional shape of the projection plane, and calculates three parameters of an azimuth angle, a tilt angle, and a distance. The projection control unit 15 calculates the focal length to be set for the variable focal length projector lens according to the distance from the projector center to the projection center obtained by the projection plane acquisition unit 13. The video output unit 14 changes the focal length of the projector lens, thereby performing projection output based on the video corrected by the video correction unit 12. Further, the focal length calculated by the projection control unit 15 is also used for the inclination correction in step S104 of the first embodiment, and is reflected in the image correction.

(4) If the distance between the projector device and the projection plane is changed beyond the depth of focus of the projection, the image on the projection plane will be blurred, and it is necessary to adjust the focus of the projector lens. In the projector device of this example, the projection control unit 5 obtains a focal length suitable for the video output unit 14 from the distance between the projection center calculated by the projection plane acquisition unit 13 and the projector device. , The focus of the projector lens is adjusted, so that even if the distance between the projector device and the projection surface changes, the image on the projection surface will not be blurred.

Third Embodiment FIG. 6 is a block diagram showing the configuration of a projector device according to a third embodiment of the present invention, and FIG. 7 is a diagram for explaining the operation of this embodiment. As shown in FIG. 6, the projector device of this example is schematically configured by a video input unit 21, a projection plane acquisition unit 23, a video output unit 24, a virtual projection plane generation unit 26, and a perspective transformation unit 27. ing. The video input unit 21, the projection plane acquisition unit 23, and the video output unit 24 are the same as the video input unit 1, projection plane acquisition unit 3, and video output unit 4 in the first embodiment shown in FIG. The virtual projection plane generation unit 26 generates a virtual approximate projection plane from the projection plane shape calculated by the projection plane acquisition unit 23. The perspective transformation unit 27 calculates a corrected image by placing a normal original image on a virtual approximation projection plane, performing perspective transformation on the image, and performing back projection simulation of an image to be displayed from the projector device on the projection plane. .

The basic configuration of the projector device of this example is almost the same as that of the above-described first embodiment, but instead of the image correction unit 2 of the first embodiment, a virtual projection plane generation unit 26 and a perspective conversion unit 27 Is different from the above. Hereinafter, the operation of the projector device of this example will be described with reference to FIG. When an original image is input from the video input unit 21, the virtual projection plane generation unit 26 generates a virtual approximate projection plane from the projection plane shape calculated by the projection plane acquisition unit 23.

Here, the virtual approximate projection plane refers to a projection plane that is natural to the user. The virtual projection plane passes through the projection center of the projection plane, and its normal vector has the same horizontal component of the normal vector of the projection plane and is parallel to the floor surface. Next, the processing of the perspective transformation unit 27 will be described with reference to FIG. A perspective transformation model is set such that the original image is normally displayed on the calculated approximate projection plane, and the original image is simulated on the virtual projection plane 210. By this projection simulation, an image to be projected and displayed on the projection plane 220 is obtained.

Further, a perspective transformation model is set such that an output image from the projector device 200 is displayed on the projection surface 220, and the image projected and displayed on the projection surface 220 is subjected to back projection simulation to perform liquid crystal (LCD) panel 230 of the projector device 200. To obtain a corrected image to be output at the position. The video output unit 24 performs projection output based on the video that has been subjected to the correction processing as described above.

The perspective transformation process is a well-known process in the field of three-dimensional computer graphics, and a circuit capable of high-speed processing is already widely used. By performing the control, the speed of the correction process can be increased.

As described above, according to the projector device of this example, on a projection surface having projections and depressions or a curved projection surface, an approximate plane serving as a virtual projection surface is calculated, and the perspective transformation is performed in the same manner as when the projection surface is a plane. By simply performing the processing, it is possible to project an image in which distortion has been corrected even when the image is projected from an arbitrary direction onto the projection plane.

Fourth Embodiment FIG. 8 is a block diagram showing a configuration of a projector apparatus according to a fourth embodiment of the present invention. FIG. 9 is a flowchart for explaining a projection plane coordinate position calculation process in a correction process according to the fourth embodiment. FIG. As shown in FIG. 8, the projector device of this example includes a video input unit 31, a video correction unit 32, a projection plane acquisition unit 33, a video output unit 34, a projection control unit 35, and a pattern image generation unit 36. And a camera 37. The video input unit 31 and the video correction unit 32 are the same as the video input unit 1 and the video correction unit 2 in the case of the first embodiment shown in FIG. The projection plane acquisition unit 33 calculates the shape of the projection plane based on the principle of triangulation from the image from the camera 37 that has captured the pattern image. The video output unit 34 performs projection output based on the corrected video from the video correction unit 32 and the pattern image from the pattern image generation unit 36. The projection control unit 35 controls to switch the input image of the video output unit 34. The pattern image generation unit 38 generates a pattern image. The camera 37 captures an image of the projection surface 38 from a direction optically different from that of the projector device.

The basic configuration of the projector device of this example is almost the same as that of the first embodiment. However, compared to the first embodiment, by using the light projection method, the processing of the projection plane acquisition unit is more flexible. They differ in that they have sex. Hereinafter, the operation of the projector device of this example will be described with reference to FIG. When an original image is input from the video input unit 1, the video correction unit 2 performs a video correction process using the data from the projection plane acquisition unit 3A. At this time, the projection plane acquisition unit 33 uses the information of the pattern image from the camera 37 to apply the principle of triangulation to a point in the image coordinate system of the projector and a corresponding point in the camera image. Thereby, the three-dimensional coordinates of the projected position of the point are obtained, and the shape of the projection plane is calculated. The video output section 34 switches and outputs the corrected video from the video correction section 32 and the pattern video from the pattern image generation section 36 under the control of the projection control section 35. The projection control unit 35 controls switching between the video input from the video correction unit 32 and the pattern video input from the pattern image generation unit 36 in the video output unit 34. The image of the projection plane 38 based on the projection output from the video output unit 34 is sent to the projection plane acquisition unit 33 via the camera 37, whereby the projection plane acquisition unit 33 Perform the calculation.

Next, the flow of the projection plane coordinate position calculation processing in the correction processing of the projector device of this example will be described with reference to FIG. At the start of the correction processing, the video output unit 4B switches the input video from the video input from the video correction unit 32 to the video input from the pattern image generation unit 36 and outputs the video (Step S301). Next, a pattern image is generated by the pattern image generation unit 36 (step S302), and the pattern image on the projection plane 38 output from the video output unit 34 is photographed by the camera 37 (step S303). The projection plane acquisition unit 33 checks which point in the image coordinate system of the projector corresponds to which point in the image coordinates of the camera from the image captured by the camera 37 and associates the point (step S305). Then, three-dimensional coordinates of the projected position of the point are calculated according to the principle of triangulation (step S306).

手法 Such a method of measuring the three-dimensional position of an object is known as a light projection method. If a sufficient number of coordinate positions cannot be obtained by one pattern projection, the necessary number of coordinate positions on the projection plane is obtained by repeating the processing of steps S302 to S304 in step S304. Is calculated. When the calculation of the position of the coordinates on the projection plane is completed, the process proceeds to step S101 of the correction processing of the first embodiment shown in FIG.

In the configuration of this example, by using a general-purpose camera, as in the case of the first embodiment, even when the image is projected from an arbitrary direction on the projection surface, it is possible to project the image with the distortion corrected. It is possible to correct the distortion of the displayed image even when the image is projected on a surface having irregularities or a curved surface.

Fifth Embodiment FIG. 10 is a block diagram showing the configuration of a projector device according to a fifth embodiment of the present invention, and FIG. 11 shows a flow of projection plane shape data calculation processing in correction processing of this embodiment. It is a flowchart. As shown in FIG. 10, the projector device of this example includes a video input unit 41, a video correction unit 42, a projection plane acquisition unit 43, a video output unit 44, a projection control unit 45, and a projection indoor shape database 46. It is roughly constituted from. The video input unit 41, the video correction unit 42, and the video output unit 44 are the same as the video input unit 1, the video correction unit 2, and the video output unit 4 in the first embodiment shown in FIG. The projection plane acquisition unit 43 acquires shape data in the projection room from the projection room shape database 46. The projection control unit 45 controls the position and direction of the projector device in the room. The projection room shape database 46 stores in advance the room shape data to be projected.

The basic configuration of the projector device of this example is almost the same as that of the first embodiment. However, the projector device has a projection room shape database 46 and stores the shape data of the room to be projected in advance. The difference is that the processing of the acquisition unit is simplified. Hereinafter, the operation of the projector device of this example will be described with reference to FIG. When an original image is input from the video input unit 41, the video correction unit 42 performs a video correction process using the data from the projection plane acquisition unit 43. At the start of the correction process, the projection plane acquisition unit 43 acquires data on the position and direction of the projector device in the room from the projection control unit 45, and also extracts the shape data of the part corresponding to the projection plane from the projection room shape database 46. The projection plane shape is acquired by converting the acquired shape data of the projection plane into the coordinates of the projector coordinate system. The video correction unit 42 corrects the input original image according to the data of the projection plane shape, and the video output unit 44 projects and outputs the corrected video. At this time, the projection control unit 45 controls the position and direction of the projector device in the projection room.

Next, the flow of projection plane shape data calculation processing in the correction processing of the projector device of this example will be described with reference to FIG. At the start of the correction process, the projection plane acquisition unit 43 acquires the position and direction data of the projector device from the projection control unit 45 (step S401), and acquires the shape data of the part corresponding to the projection plane from the projection room shape data 46. Then, the shape data of the projection plane is converted into coordinates in the projector coordinate system to calculate data of the projection plane shape (step S403). Then, when the calculation of the projection plane shape data is completed, the flow shifts to step S101 of the correction processing of the first embodiment shown in FIG.

As described above, in the projector device of this example, since the shape of the projection plane is obtained by converting the data stored in advance, the processing is simplified, and high-speed processing can be performed.

Sixth Embodiment FIG. 12 is a block diagram showing a configuration of a projector device according to a sixth embodiment of the present invention. As shown in FIG. 12, the projector device of this example includes a video input unit 51, a video correction unit 52, a projection plane acquisition unit 53, a video output unit 54, a marker detection unit 55, and a projection indoor shape database 56. It is roughly constituted from. The video input unit 51, the video correction unit 52, and the video output unit 54 are the same as the video input unit 1, the video correction unit 2, and the video output unit 4 in the first embodiment shown in FIG. The projection plane acquisition unit 53 acquires the shape data of the inside of the projection room from the projection room shape database 56, and acquires marker detection information from the marker detection unit 55. The marker detecting section 55 detects a marker mounted in the projection room. The projection room shape database 46 stores in advance the room shape data to be projected.

The basic configuration of the projector device of this example is almost the same as that of the first embodiment. However, the projector device has a projection room shape database 56, which stores the shape data of the room to be projected in advance and sets the marker detection unit 55 The difference is that the processing of the projection plane obtaining unit is simplified by detecting the marker attached in the projection room and acquiring the data of the position and direction of the projector device. Hereinafter, the operation of the projector device of this example will be described with reference to FIG. When an original image is input from the video input unit 51, the video correction unit 52 performs a video correction process using data from the projection plane acquisition unit 53. At the start of the correction process, the marker detection unit 55 observes, for example, a marker that is attached to the wall surface of the projection room and serves as an identifier (ID) of the wall surface using a sensor (not shown) added to the projector device. Thus, data on the position and direction of the projector device is acquired. The projection plane acquisition unit 53 acquires the data of the position and direction of the projector device from the marker detection unit 55, and acquires the shape data of the part corresponding to the projection plane from the projection room shape database 56, and The shape data of the projection plane is converted into coordinates in the projector coordinate system according to the direction data, thereby acquiring the shape of the projection plane. The video correction unit 52 corrects the input original image according to the data of the projection plane shape, and the video output unit 54 projects and outputs the corrected video.

As described above, in the projector device of this example, instead of controlling the position and the direction of the projector device in the projection room, the data of the position and the direction of the projector device in the projection room is acquired using the marker. . Since marker detection can be realized with a small sensor, the device configuration can be reduced in size and weight.

As described above, the embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and even if there is a design change or the like within a range not departing from the gist of the present invention. Included in the invention. For example, in the above-described second embodiment, the focal length may be adjusted by changing the position of a liquid crystal (LCD) panel or the like in the projector device, instead of setting the projector lens to have a variable focal length. . In the sixth embodiment, instead of attaching the marker in the projection room, the marker may be attached to the projector device itself, and the marker may be observed by a sensor installed in the room. Further, in the above-described first embodiment, the case has been described where the image correction unit 2 first performs the scaling correction and then performs the tilt correction. However, the present invention is not limited to this. Correction may be performed. Further, for example, a laser device may be used instead of the liquid crystal (LCD) panel.

FIG. 1 is a block diagram schematically illustrating a configuration of a projector device according to a first embodiment of the present invention. It is a flowchart which shows the flow of the correction processing in the embodiment. FIG. 3 is a diagram illustrating a process of scaling correction in the embodiment. FIG. 4 is a diagram illustrating a process of tilt correction in the embodiment. FIG. 9 is a block diagram schematically showing a configuration of a projector device according to a second embodiment of the present invention. FIG. 13 is a block diagram schematically illustrating a configuration of a projector device according to a third embodiment of the present invention. FIG. 4 is an explanatory diagram for explaining an operation of the embodiment. FIG. 14 is a block diagram schematically showing a configuration of a projector device according to a fourth embodiment of the present invention. 9 is a flowchart illustrating a flow of projection plane coordinate position calculation processing in the correction processing of the embodiment. FIG. 14 is a block diagram schematically showing a configuration of a projector device according to a fifth embodiment of the present invention. 9 is a flowchart illustrating a flow of projection plane shape data calculation processing in the correction processing of the embodiment. FIG. 16 is a block diagram schematically showing a configuration of a projector device according to a sixth embodiment of the present invention. FIG. 11 is a diagram illustrating an example of a video correction method according to the related art.

Explanation of reference numerals

1,11,21,31,41,51 Video input unit (video input means)
2,12,22,32,42,52 Video correction unit (Video correction means)
3, 13, 23, 33, 43, 53 Projection plane acquisition unit (projection plane acquisition means)
4,14,24,34,44,54 Video output unit (video output means)
15, 35, 45 Projection control unit (projection control means)
26 virtual projection plane generation unit (virtual projection plane generation means)
27 Perspective conversion unit (perspective conversion means)
36 pattern image generation unit (pattern image generation means)
37 Camera 38 Projection surface 46 Projection room shape database 55 Marker detector (marker detector)
56 Projection room shape database 100 Projector device 110 Projection plane 111 Temporary reference plane 112 Reference plane

Claims (5)

Video input means for inputting an original image;
Projection plane acquisition means for calculating a tilt angle and a distance of the projection plane from a normal vector of the projection plane,
Using the inclination angle and the distance calculated by the projection plane acquisition means, image correction means for performing distortion correction processing on the input original image corresponding to the shape of the projection plane,
Video output means for projecting and outputting the corrected image,
The image correction means,
A process of changing the distance between the reference plane and the center of the projector, which is a plane on which an image photographed on the projection plane is displayed and which is a reference plane, and the distance, Changing the image of the temporary reference plane passing through the intersection of the projector optical axis and the projection plane into the image of the projection plane using the inclination angle. Video input means for inputting an original image;
Projection plane acquisition means for calculating an azimuth, a tilt angle and a distance of the projection plane from a normal vector of the projection plane;
Using the azimuth angle, the tilt angle, and the distance calculated by the projection plane acquisition unit, a video correction unit that performs distortion correction processing on the input original image in accordance with the shape of the projection plane.
Video output means for projecting and outputting the corrected image,
The distortion correction process,
Rotating the original image according to the azimuth angle and changing the size according to the ratio of the distance and the focal length of the projector lens, and changing the coordinates of the image on the temporary reference plane according to the distance and the tilt angle A projector apparatus, comprising: a tilt correction to be changed; and an enlargement / reduction correction to change coordinates of an original image in accordance with a ratio of a distance from the center of the projector to a reference plane and the distance. 2. A projection control unit for calculating a focal length of a projector lens according to a distance of the projection plane calculated by the projection plane acquisition unit and performing focus control in the video output unit. 3. The projector device according to 2. 4. The projector device according to claim 3, wherein the tilt correction is performed according to the focal length calculated by the projection control unit. Video input means for inputting an original image;
Projection plane acquisition means for calculating an azimuth, a tilt angle and a distance of the projection plane from a normal vector of the projection plane to acquire a three-dimensional shape of the projection plane;
Virtual projection plane generation means for generating a virtual projection plane from the projection plane shape calculated by the projection plane acquisition means,
Perspective transformation means for calculating a corrected image by projecting a three-dimensional image obtained by back-projection simulation of the input original image on the virtual projection plane by perspective transformation processing,
Video output means for projecting and outputting the corrected image.

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