Video processing method, program, and video processing system

Abstract

To easily detect the secular deviation of the display position of a video by a projector.SOLUTION: In the video processing method, a captured image obtained by imaging a projection area with an imaging device is acquired for each of a plurality of projection devices (S10). In the video processing method, for each of the plurality of projection devices, a feature area that is a part of the projection area in the acquired captured image and has a feature that can be distinguished from other parts is calculated (S12). In the video processing method, for each of the plurality of projectors, a test image that includes the calculated characteristic region and that is projected onto the display surface in order to check whether or not the projection region is shifted from the reference region is generated based on coordinate correlative information indicating correlations between coordinate systems of the imaging device and coordinate systems of the projectors (S14). In the video processing method, the generated test image is output to each of the plurality of projectors (S15).SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present disclosure relates to a video processing method, a program, and a video processing system. [Background technology]

[0002] Patent Document 1 discloses an image display system in which a content image indicated by image data input from a signal source is shared among a plurality of projectors and projected onto a projection surface such as a screen or a wall. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-182077 Summary of the Invention [Problem to be solved by the invention]

[0004] The present disclosure provides an image processing method and the like that makes it easy to detect a shift over time in the display position of an image displayed by a projection device. [Means for solving the problem]

[0005] An image processing method according to one aspect of the present disclosure acquires, for each of a plurality of projection devices that project an image onto a display surface of an object, an image captured by an imaging device of a projection area on the display surface of the object where the image projected by the projection device occupies; calculates a characteristic area that is a part of the projection area in the acquired image and has characteristics that can be distinguished from other parts; generates a test image that includes the calculated characteristic area based on coordinate correlation information that indicates the correlation between the coordinate system of the imaging device and the coordinate system of the projection device, to be projected onto the display surface to check whether the projection area deviates from a reference area; and outputs the generated test image to the projection device. [Effects of the Invention]

[0006] The present disclosure has an advantage in that it is easy to detect a shift over time in the display position of an image projected by a projection device. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a schematic diagram showing an overall configuration including a video processing system according to the first embodiment. [Figure 2] FIG. 2 is a block diagram showing the configuration of the projection device according to the first embodiment. [Figure 3] FIG. 3 is a flowchart illustrating an example of the operation of the control device according to the first embodiment. [Figure 4] FIG. 4 is a schematic diagram illustrating an example of the operation of the control device according to the first embodiment. [Figure 5] FIG. 5 is a diagram showing an example of a pattern image for coordinate detection. [Figure 6] FIG. 6 is a flowchart showing an example of the operation of the projection device according to the first embodiment. [Figure 7] FIG. 7 is an explanatory diagram of the shift over time in the display position of an image projected by a projection device. [Figure 8] FIG. 8 is a schematic diagram illustrating an example of the operation of the projection device according to the first embodiment. [Figure 9] FIG. 9 is a schematic diagram showing an overall configuration including a video processing system according to the second embodiment. [Figure 10] FIG. 10 is a flowchart illustrating an example of the operation of the control device according to the second embodiment. [Figure 11] FIG. 11 is a schematic diagram illustrating an example of the operation of the control device according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] [1. Findings that formed the basis of this disclosure] First, the inventor's point of view will be explained below.

[0009] Conventionally, a technology has been known in which a single image is displayed on a display surface of an object such as a screen by projecting images from each of a plurality of projection devices (projectors). For example, of two projection devices (a first projection device and a second projection device), a first image is projected onto the display surface from a first projection device, and a second image is projected onto the display surface from a second projection device, so that a single image made up of the first and second images is displayed on the display surface. The first and second images may or may not partially overlap on the display surface.

[0010] Incidentally, there are cases where an event is held over a long period of time in which an image is displayed on a display surface of an object. In such cases, if multiple projection devices are installed over a long period of time, there is a possibility that the image projected on the display surface will become misaligned over time. This misalignment can occur, for example, due to a misalignment in the installation position of at least one of the multiple projection devices. When this misalignment occurs, the image projected on the display surface will become distorted, and geometric correction must be performed to eliminate the misalignment.

[0011] Here, for example, when performing geometric correction using a media server for playing back images on multiple projection devices, in order to check whether the above-mentioned time-dependent deviation occurs, it is necessary to have each projection device project a test image that has been subjected to a corresponding geometric correction (i.e., the same geometric correction as that applied to the image) from the media server, which presents the problem that this is a cumbersome means of detecting the above-mentioned time-dependent deviation.

[0012] Furthermore, when performing geometric correction on each projection device, it is conceivable to check whether the above-mentioned misalignment occurs over time by projecting a test image with a crosshatching pattern stored in advance in each projection device onto the display surface. However, in this case, depending on the degree of edge blending, the lines of the test images projected from each projection device may not align, making it difficult to detect the above-mentioned misalignment over time.

[0013] In view of the above, the inventors have come up with the present disclosure.

[0014] Hereinafter, the first and second embodiments will be described with reference to the drawings. Note that the first and second embodiments described below are either comprehensive or specific examples. The numerical values, shapes, materials, components, component placement and connection forms, steps, step order, etc. shown in the first and second embodiments below are merely examples and are not intended to limit the present disclosure. Furthermore, among the components in the first and second embodiments below, components not recited in the independent claims will be described as optional components.

[0015] It should be noted that the drawings are schematic diagrams and are not necessarily strict illustrations. In addition, in the drawings, substantially the same components are denoted by the same reference numerals, and overlapping descriptions may be omitted or simplified.

[0016] (Embodiment 1) [2. Configuration] [2-1. Overall Structure] First, the overall configuration including the image processing system 100 according to the first embodiment will be described. FIG. 1 is a block diagram showing the overall configuration including the image processing system 100 according to the first embodiment. In the first embodiment, the image processing system 100 is realized by a control device 3 that controls a plurality of projection devices 1 (here, two projection devices 1A and 1B) and one imaging device 2. Hereinafter, when there is no need to distinguish between the two projection devices 1A and 1B, they will be referred to as "projection device 1."

[0017] Projection device 1 is a device with projector functions, and projects an image onto display surface 40 of object 4 (here, screen 41) based on video data included in a video signal transmitted from a playback device (not shown). Note that projection device 1 is not limited to projecting an image onto display surface 40 of screen 41, and may also project an image onto one surface of a structure 42 (see FIG. 9 ) other than screen 41, such as a wall surface, as display surface 40, as in a second embodiment described below. In the first embodiment, two projection devices 1A and 1B each project an image onto display surface 40, thereby projecting a composite image onto display surface 40.

[0018] A playback device is a device that has the function of playing back video recorded on optical media such as a DVD (Digital Versatile Disc, registered trademark) or a BD (Blu-ray (registered trademark) Disc). Note that a playback device may also be a device that has the function of playing back video recorded on a storage device such as an HDD (Hard Disc Drive).

[0019] The imaging device 2 is a device with a remotely controllable camera function, and captures the image projected on the display surface 40. In the first embodiment, the imaging device 2 receives control commands from the control device 3 to perform various controls such as adjusting exposure or focus, capturing the image, and acquiring the captured data. Note that in the first embodiment, the imaging device 2 is a separate device from the projection device 1, but it may be built into the projection device 1. Specifically, the imaging device 2 may be built into either the projection device 1A or 1B.

[0020] The control device 3 is an information terminal such as a desktop or laptop personal computer, and controls each of the projection devices 1 and the imaging device 2 by communicating with each of the projection devices 1 and the imaging device 2 via a network N1 such as a LAN (Local Area Network). The communication between each of the projection devices 1 and the imaging device 2 and the control device 3 is performed in accordance with a known network protocol such as HTTP (Hypertext Transfer Protocol), FTP (File Transfer Protocol), or TCP (Transmission Control Protocol).

[0021] In the first embodiment, the control device 3 is realized by installing software dedicated to the video processing system 100 in a general-purpose information terminal. Note that the control device 3 is not limited to a general-purpose information terminal, but may also be an information terminal dedicated to the video processing system 100. Furthermore, the information terminal is not limited to a personal computer, but may also be realized by, for example, a smartphone or a tablet terminal.

[0022] [2-2.Projection equipment] Next, the configuration of the projection device 1 will be described in detail. Fig. 2 is a block diagram showing the configuration of the projection device 1 according to the first embodiment. As shown in Fig. 2, the projection device 1 includes an image input unit 11, an image generation unit 12, an image synthesis / selection unit 13, an image adjustment unit 14, an image projection unit 15, an input unit 16, a communication unit 17, a control unit 18, and a storage unit 19. The image input unit 11, the image generation unit 12, the image synthesis / selection unit 13, the image adjustment unit 14, the image projection unit 15, the input unit 16, the communication unit 17, and the control unit 18 may each be realized by a dedicated circuit, or may be realized by a processor executing a corresponding computer program stored in a memory.

[0023] The video input unit 11 acquires a video signal input from an external device (here, a playback device) and converts the acquired video signal into an internal video signal. Here, the resolution and frame rate of the video signal are not particularly limited. In other words, video signals having various resolutions or frame rates are input to the video input unit 11 from the playback device.

[0024] Video generation unit 12 performs various processes on the internal video signal from video input unit 11. For example, when video generation unit 12 receives an input from input unit 16 instructing the display of a menu image, video generation unit 12 generates a menu image to be projected on display surface 40. Furthermore, when video generation unit 12 receives an input from input unit 16 instructing the display of a test image P3 (see FIG. 4 ), which will be described later, video generation unit 12 reads image data of test image P3 from storage unit 19 and generates test image P3 to be projected on display surface 40 based on the read image data.

[0025] When input unit 16 receives a menu operation input, video synthesis / selection unit 13 executes a process of selecting a composite video obtained by synthesizing the internal video signal from video input unit 11 with the video (image) generated by video generation unit 12 as the video to be projected on display surface 40. Furthermore, when input unit 16 receives an input instructing the display of test image P3, video synthesis / selection unit 13 executes a process of selecting test image P3 generated by video generation unit 12 as the video to be projected on display surface 40.

[0026] Image adjustment unit 14 performs image adjustment processing such as preset color correction or geometric correction on the internal image signal. Image adjustment data used by image adjustment unit 14 is stored in storage unit 19 and can be changed in response to a user's operation input at input unit 16 or by remote control via communication unit 17.

[0027] Image projection unit 15 projects an image onto display surface 40 in accordance with the image selected by image synthesis / selection unit 13. Image projection unit 15 has a light source, a modulation element such as a DMD (Digital Micro Mirror Device), and a projection lens. Image projection unit 15 can change the brightness of the light source and perform lens control such as zoom, shift, focus, or shutter in response to a user's operation input at input unit 16 or by remote control via communication unit 17.

[0028] The input unit 16 is an interface for accepting operation inputs from a user, and includes, for example, one or more buttons or an infrared light receiving unit provided on the main body of the projection device 1. In the first embodiment, the input unit 16 accepts, for example, an input of an instruction to project the test image P3 onto the display surface 40.

[0029] The communication unit 17 is a communication interface for communicating with an external device (for example, the control device 3 or another projection device 1) via the network N1. The communication unit 17 receives control commands or data transmitted from the external device. The data includes the test image P3. Note that the communication between the communication unit 17 and the external device may be wired or wireless.

[0030] The control unit 18 controls the projection device 1 by executing various processes related to the projection device 1. For example, when the communication unit 17 receives a control command or data from an external device, the control unit 18 controls the projection device 1 by executing a process according to the received control command or data. The control unit 18 also transmits the results of the process executed according to the received control command via the communication unit 17 to the external device that sent the control command. In the first embodiment, the control unit 18 executes a process to display a test image P3 on the display surface 40. Details of this process will be explained in "3-2. Example of Projection Device Operation" below.

[0031] The storage unit 19 is, for example, a semiconductor memory or the like, and stores various data related to the projection device 1. In the first embodiment, the storage unit 19 stores a test image P3 received from an external device by the communication unit 17. The storage unit 19 also stores a pattern image PP1 (see FIG. 5) for coordinate detection, which will be described later.

[0032] [2-3. Control Device] Next, a detailed description will be given of the configuration of the control device 3. As shown in Fig. 1, the control device 3 includes an input unit 31, a screen display unit 32, a communication unit 33, a processing unit 34, and a storage unit 35. The input unit 31, the screen display unit 32, the communication unit 33, and the processing unit 34 may each be realized by a dedicated circuit, or may be realized by a processor executing a corresponding computer program stored in a memory.

[0033] The input unit 31 receives an input from a user using, for example, a keyboard or a pointing device such as a mouse. In the first embodiment, the input unit 31 receives, for example, an input instructing execution of a process for generating a test image P3.

[0034] The screen display unit 32 displays a UI (User Interface) screen for operating the control device 3 on a display attached to the control device 3. For example, the screen display unit 32 displays an HTML page or the like generated by the imaging device 2 on the display.

[0035] The communication unit 33 is a communication interface for communicating with an external device (for example, the projection device 1 or the imaging device 2) via the network N1. The communication unit 33 transmits, for example, a control command to the external device. The communication unit 33 also transmits, for example, a test image P3 (see FIG. 4) generated by the processing unit 34 to each projection device 1. Note that the communication between the communication unit 33 and the external device may be wired communication or wireless communication.

[0036] The processing unit 34 executes various processes related to the control device 3. In the first embodiment, the processing unit 34 executes a process of generating a test image P3 and outputting (transmitting) the generated test image P3 to each projection device 1 via the communication unit 33. Details of this process will be explained in [3-1. Example of operation of the control device].

[0037] The storage unit 35 is, for example, a semiconductor memory or the like, and stores the captured image P1 (see FIG. 4) acquired from the imaging device 2. The storage unit 35 also stores, for example, a test image P3 generated by the processing unit 34 for each projection device 1.

[0038] [3. Operation] The operation of the entire configuration including the video processing system 100 (control device 3) according to the first embodiment will be described below.

[0039] [3-1. Example of control device operation] First, an example of the operation of the control device 3 according to the first embodiment will be described with reference to Figs. 3 and 4. Fig. 3 is a flowchart showing an example of the operation of the control device 3 according to the first embodiment. Fig. 4 is a schematic diagram showing an example of the operation of the control device 3 according to the first embodiment. In the following, as shown in Fig. 1, the description will be given assuming that each of the projection device 1A and the projection device 1B projects an image onto the display surface 40 of the screen 41. Therefore, an image that is a composite of the image projected by the projection device 1A and the image projected by the projection device 1B is displayed on the display surface 40.

[0040] Hereinafter, the area on the display surface 40 (or captured image P1) occupied by the image projected by the projection device 1A will be referred to as the "first projection area A11," and the area on the display surface 40 (or captured image P1) occupied by the image projected by the projection device 1B will be referred to as the "second projection area A12." Also, hereafter, the area on the display surface 40 (or captured image P1) where the first projection area A11 and the second projection area A12 overlap will be referred to as the "common area A2."

[0041] In the following description, it is assumed that the input unit 31 of the control device 3 has received an instruction from the user to execute the process of generating the test image P3.

[0042] 3, first, the processing unit 34 of the control device 3 instructs, via the communication unit 33, a specific one of the multiple projection devices 1 to project an image in which all pixels are white onto the display surface 40, and instructs all other projection devices 1 to project an image in which all pixels are black onto the display surface 40. Then, the processing unit 34 instructs the imaging device 2 via the communication unit 33 to capture an image of the display surface 40 and transmit the captured image P1 obtained by the capture. Thereafter, the processing unit 34 executes the above process for all projection devices 1. As a result, the processing unit 34 acquires the captured image P1 for each projection device 1 (S10).

[0043] Next, the processing unit 34 executes an appropriate extraction process for each acquired captured image P1 to extract a projection area in the captured image P1 occupied by the image projected by the projection device 1 (S11). Here, the projection area of ​​a specific projection device 1 in the captured image P1 is a white area, and the other areas are black areas, so by executing a known extraction process that extracts contours, it is possible to extract the projection area of ​​the specific projection device 1. Here, as shown in "S11" in FIG. 4, the processing unit 34 extracts a first projection area A11 that is the projection area for the projection device 1A in the captured image P1, and a second projection area A12 that is the projection area for the projection device 1B in the captured image P1.

[0044] Returning to FIG. 3, the processing unit 34 calculates a characteristic region from the extracted projection region in the captured image P1 of each projection device 1 (S12). A characteristic region is a part of the projection region in the captured image P1 and has characteristics that can be distinguished from other parts. Here, as shown in "S12" in FIG. 4, the processing unit 34 calculates the common region A2, which is an area where the first projection region A11 and the second projection region A12 overlap, as the characteristic region.

[0045] Returning to FIG. 3, the processing unit 34 generates a misalignment check image P2 that includes the characteristic region (here, the common region A2) and is used to check whether the projection region of each projection device 1 is misaligned from the reference region (S13). Here, the reference region refers to the projection region of the projection device 1 in its initial state when the projection device 1 is installed. Specifically, the processing unit 34 prepares an image with the same resolution as the captured image P1, and draws a predetermined pattern only in the region A21 of the image that corresponds to the common region A2, and masks the remaining region in a uniform color. Here, as shown in "S13" in FIG. 4, the processing unit 34 draws a cross-hatched pattern as the predetermined pattern only in the region A21 that corresponds to the common region A2, and generates the misalignment check image P2 in which the remaining region is masked in black.

[0046] 4, the color of the lines in the crosshatching pattern is white, but other colors may be used. Furthermore, the predetermined pattern drawn in the common area A2 is not limited to a crosshatching pattern, and may be any other pattern, such as a dot hatching pattern, as long as it allows the user to easily visually determine the deviation of the projection area. Furthermore, the remaining area is not limited to a mask area drawn in a uniform color, and may be a mask area drawn in a pattern that can be distinguished from the common area A2.

[0047] 3, based on the misalignment check image P2, the processing unit 34 generates a test image P3 for each projection device 1 to be projected onto the display surface 40 in order to check the misalignment of the projection area (S14). Specifically, the processing unit 34 refers to coordinate correlation information that indicates the correlation between the coordinate system of the imaging device 2 and the coordinate system of the projection device 1, which is stored in advance in the storage unit 35, and converts each coordinate of the misalignment check image P2 into the coordinate of the projection device 1, thereby generating the test image P3 from the misalignment check image P2.

[0048] Here, the processing unit 34 generates a test image P31 for the projection device 1A and a test image P32 for the projection device 1B, as shown in "S14" in FIG. 4. The test image P31 is an image obtained by cutting out the first projection area A11 for the projection device 1A from the misalignment check image P2. The test image P32 is an image obtained by cutting out the second projection area A12 for the projection device 1B from the misalignment check image P2. In the test image P31, a predetermined pattern (here, a cross-hatching pattern) is drawn in the first common area A31 that corresponds to the common area A2 in the misalignment check image P2. In addition, in the test image P32, a predetermined pattern (here, a cross-hatching pattern) is drawn in the second common area A32 that corresponds to the common area A2 in the misalignment check image P2.

[0049] Here, the colors of the lines in the predetermined pattern are different from one another in the multiple test images P3 corresponding to the multiple projection devices 1. Furthermore, here, the combination of the color of the lines in the predetermined pattern in any one test image P3 among the multiple test images P3 and the color of the lines in the predetermined pattern in another test image P3 has a complementary color relationship.

[0050] Specifically, the color of the lines in the predetermined pattern of test image P31 is magenta, and the color of the lines in the predetermined pattern of test image P32 is yellow. Magenta and yellow are complementary colors, and when mixed together they form red. Therefore, by looking at the color of the lines in the predetermined pattern, the user can easily visually determine whether the lines in the predetermined pattern overlap, i.e., whether there is a misalignment in the projection area.

[0051] The combination of the line colors in the predetermined pattern of test image P31 and the line colors in the predetermined pattern of test image P32 is not limited to magenta and yellow, but may be other combinations of complementary colors. The combination may also be a combination of colors that are not complementary. Furthermore, the line colors in the predetermined pattern of test image P31 and the line colors in the predetermined pattern of test image P32 may be the same.

[0052] Here, an example of a method for acquiring coordinate correlation information will be described. First, the processing unit 34 instructs one of the predetermined projection devices 1 via the communication unit 33 to project a pattern image PP1 (see FIG. 5) for coordinate detection onto the display surface 40. Then, the processing unit 34 instructs the imaging device 2 via the communication unit 33 to capture an image of the display surface 40 and transmit the captured image. Thereafter, the processing unit 34 executes the above process for all projection devices 1. As a result, the communication unit 33 acquires the captured image for each projection device 1.

[0053] FIG. 5 shows an example of a pattern image PP1 for coordinate detection. In FIG. 5, each pixel is color-coded according to the type of hatching. Here, the feature point SP1 is the intersection of four regions, where the colors of the upper region, lower region, right region, and left region are all different from one another. In the pattern image PP1, there is only one point where the colors of the upper region, lower region, right region, and left region form a specific combination. The processing unit 34 detects the intersection of the four regions in the captured image that form the specific color combination as the feature point SP1 of the pattern image PP1. Then, by referring to the detected feature point SP1, the processing unit 34 calculates the correlation between the coordinate system of the imaging device 2 and the coordinate system of the projection device 1, and stores the calculated correlation information in the storage unit 35 as coordinate correlation information. Subsequently, the processing unit 34 calculates the correlation for each projection device 1 and stores the coordinate correlation information for each projection device 1 in the storage unit 35.

[0054] Returning to FIG. 3, the processing unit 34 outputs the generated test image P3 to each projection device 1 (S15). Here, the processing unit 34 transmits the test image P3 to each projection device 1 via the communication unit 33. Upon receiving the test image P3 via the communication unit 17, each projection device 1 stores the received test image P3 in the storage unit 19.

[0055] 4, the processing unit 34 transmits a test image P31 to the projection device 1A and transmits a test image P32 to the projection device 1B. Then, when the projection device 1A receives the test image P31, the processing unit 34 stores the test image P31 in the storage unit 19. Furthermore, when the projection device 1B receives the test image P32, the processing unit 34 stores the test image P32 in the storage unit 19.

[0056] [3-2. Projector operation example] Next, an example of the operation of the projection device 1 according to the first embodiment will be described with reference to FIGS. 6, 7, and 8. FIG. 6 is a flowchart showing an example of the operation of the projection device 1 according to the first embodiment. FIG. 7 is an explanatory diagram of a time-dependent shift in the display position of an image projected by the projection device 1. FIG. 8 is a schematic diagram showing an example of the operation of the projection device 1 according to the first embodiment. (a) of FIG. 7 is a diagram showing a case where no time-dependent shift occurs in the first projection area A11 of the projection device 1A and the second projection area A12 of the projection device 1B on the display surface 40 of the screen 41. (b) of FIG. 7 is a diagram showing a case where time-dependent shift occurs in the second projection area A12 of the projection device 1B on the display surface 40 of the screen 41. In (b) of FIG. 7, the rectangular frame indicated by the dashed line represents the reference area of ​​the second projection area A12, and the rectangular frame indicated by the solid line represents the second projection area A12 where time-dependent shift occurs.

[0057] In the following description, it is assumed that the input unit 16 of a predetermined one of the plurality of projection devices 1 has received an instruction from the user to project the test image P3 onto the display surface 40.

[0058] First, upon receiving the above instruction, the control unit 18 of the predetermined projection device 1 reads out the test image P3 from the storage unit 19 and projects the read-out test image P3 onto the display surface 40. The control unit 18 of the predetermined projection device 1 also transmits the above instruction to all other projection devices 1 via the communication unit 17. Each of the other projection devices 1 that received the above instruction reads out the test image P3 from the storage unit 19 and projects the read-out test image P3 onto the display surface 40, just like the predetermined projection device 1. As a result, each projection device 1 projects the test image P3 onto the display surface 40 (S20). Here, the projection device 1A projects the test image P31 onto the display surface 40, and the projection device 1B projects the test image P32 onto the display surface 40.

[0059] The user can check whether there is any misalignment in the projection areas of the projection devices 1 by looking at each test image P3 projected onto the display surface 40. Here, a predetermined pattern (here, a cross-hatching pattern) is projected onto the display surface 40 in an area of ​​each test image P3 that corresponds to the common area A2. Therefore, the user can check whether there is any misalignment in the projection areas of the projection devices 1 by looking at only the predetermined pattern projected onto the display surface 40 from each projection device 1, without looking at the entire test image P3 projected onto the display surface 40.

[0060] Specifically, as shown in FIG. 8, the user checks the degree of overlap between the first common area A31 in the test image P31 and the second common area A32 in the test image P32. As previously mentioned, the color of the lines of the predetermined pattern in the test image P31 is magenta, and the color of the lines of the predetermined pattern in the test image P32 is yellow. Therefore, if the user can visually confirm these colors, as shown in FIG. 8(a), the user can determine that the first projection area A11 of the projection device 1A and the second projection area A12 of the projection device 1B are deviated from the reference state, i.e., that there is a deviation in at least one of the projection areas. On the other hand, if the user can visually confirm that the color of the predetermined pattern is red, not magenta or yellow, as shown in FIG. 8(b), the user can determine that the first projection area A11 of the projection device 1A and the second projection area A12 of the projection device 1B are not deviated from the reference state, i.e., that there is no deviation in either of the projection areas.

[0061] The color of the outline of the test image P3 may be the same as the color of the predetermined pattern. In this case, by looking at the color of the outline of the test image P3, the user can easily understand which projection device 1 has a misalignment in its projection area.

[0062] 6, if the user determines that an unacceptable misalignment has occurred in the projection area of ​​at least one of the projection devices 1 (S21: Yes), the user performs an operation such as adjusting the lens shift amount of that projection device 1. This causes the control unit 18 of that projection device 1 to correct the misalignment in accordance with the operation (S22). Here, the user simply adjusts the lens shift amount of that projection device 1 so that the predetermined patterns of the test images P3 projected on the display surface 40 match, making it easy to correct the misalignment.

[0063] On the other hand, if the user determines that there is no misalignment in the projection area of ​​any of the projection devices 1 (S21: No), the user operates one of the projection devices 1 to input an instruction to stop projecting the test image P3 onto the display surface 40. As a result, the control unit 18 of the projection device 1 that received the input of this instruction stops projecting the test image P3 onto the display surface 40. The control unit 18 of that projection device 1 also transmits the above instruction to all other projection devices 1 via the communication unit 17. All other projection devices 1 that have received the above instruction each stop projecting the test image P3 onto their display surfaces 40. This completes the process of checking whether there is any misalignment in the projection area of ​​any of the projection devices 1.

[0064] The misalignment correction in step S22 may be performed automatically by the processing unit 34 of the control device 3. For example, a user inputs an instruction to execute misalignment correction processing by operating any of the projection devices 1. Upon receiving the input of the instruction, the projection device 1 transmits the instruction to the control device 3 via the communication unit 17.

[0065] When the processing unit 34 of the control device 3 receives the instruction via the communication unit 33, it instructs the imaging device 2 via the communication unit 33 to capture an image of the display surface 40 and transmit the captured image obtained by capturing the image, thereby acquiring the captured image. Then, the processing unit 34 transmits an instruction via the communication unit 33 to one of the projection devices 1 to adjust the lens shift amount so that the predetermined patterns of each test image P3 match in the acquired captured image. Upon receiving the instruction, the projection device 1 adjusts the lens shift amount in accordance with the instruction. This automatically performs the misalignment correction in step S22.

[0066] [4. Advantages, etc.] The advantages of the video processing system 100 (video processing method) according to the first embodiment will be described below. As described above, the video processing system 100 according to the first embodiment generates, from a captured image P1 capturing the projection area of ​​each projection device 1, a deviation check image P2 that includes a characteristic region (here, the common region A2) and is used to check whether the projection area of ​​each projection device 1 is deviated from the reference region. Furthermore, the video processing system 100 according to the first embodiment generates, from the generated deviation check image P2, a test image P3 that is projected onto the display surface 40 for checking the deviation of the projection area, for each projection device 1, based on coordinate correlation information that indicates the correlation between the coordinate system of the imaging device 2 and the coordinate system of the projection device 1. Then, the video processing system 100 according to the first embodiment outputs the generated test image P3 to the projection device 1 for each projection device 1.

[0067] Therefore, if a user wants to check whether there is a shift over time in the display position of images projected by multiple projection devices 1, the user can project test image P3 from each projection device 1 onto display surface 40 and look at the feature area (here, common area A2) of each test image P3 projected onto display surface 40, thereby visually determining whether there is a shift in the projection area of ​​each projection device 1, even if geometric correction has not been performed by each projection device 1. Therefore, the image processing system 100 according to the first embodiment has the advantage that it is easy to detect a shift over time in the display position of images projected by the projection devices 1.

[0068] (Embodiment 2) An image processing system 100A according to the second embodiment will be described below with reference to FIG. 9. FIG. 9 is a schematic diagram showing the overall configuration including the image processing system 100A according to the second embodiment. As shown in FIG. 9, the second embodiment differs from the first embodiment in that the object 4 is not a screen 41 but a structure 42 such as a building. Therefore, in the second embodiment, one surface of the structure 42 becomes the display surface 40. Furthermore, in the second embodiment, the image processing system 100A is realized by the control device 3, similar to the first embodiment. Note that the configurations of the multiple projection devices 1 (here, projection devices 1A and 1B), the imaging device 2, and the control device 3 are the same as those in the first embodiment, and therefore, description of the common points will be omitted where appropriate.

[0069] The operation of the entire configuration including the image processing system 100A (control device 3) according to the second embodiment will be described below. FIG. 10 is a flowchart showing an example of the operation of the control device 3 according to the second embodiment. FIG. 11 is a schematic diagram showing an example of the operation of the control device 3 according to the second embodiment. In the following, it is assumed that each of the projection device 1A and the projection device 1B projects an image onto the display surface 40 of the structure 42, as shown in FIG. 9. Therefore, an image that is a composite of the image projected by the projection device 1A and the image projected by the projection device 1B is displayed on the display surface 40. In addition, in the following, it is assumed that the input unit 31 of the control device 3 has received an input from the user instructing it to execute processing to generate a test image P3.

[0070] 10, first, the processing unit 34 of the control device 3 acquires a captured image P1 for each projection device 1 (S30), similar to step S10 in the first embodiment. The processing unit 34 also acquires a captured image P1' (see FIG. 11) of only one surface of the structure 42 by having the imaging device 2 capture an image of the display surface 40 when no image is projected from each projection device 1 (S30).

[0071] Next, similar to step S11 in the first embodiment, the processing unit 34 executes an appropriate extraction process for each acquired captured image P1 to extract a projection area in the captured image P1 occupied by the image projected by the projection device 1 (S31). Here, as shown in "S31" in Fig. 11, the processing unit 34 extracts a first projection area A11 which is the projection area for the projection device 1A in the captured image P1, and a second projection area A12 which is the projection area for the projection device 1B in the captured image P1.

[0072] 10, similar to step S12 in the first embodiment, the processing unit 34 calculates a characteristic region from the extracted projection region in the captured image P1 of each projection device 1 (S32). Here, as shown in "S32" in FIG. 11, the processing unit 34 calculates the common region A2, which is the region where the first projection region A11 and the second projection region A12 overlap, as the characteristic region.

[0073] 10, the processing unit 34 generates a misalignment check image P2 (S33), similar to step S13 in embodiment 1. Here, as shown in "S33" in Fig. 11, the processing unit 34 draws a cross-hatching pattern as a predetermined pattern only in the area A21 corresponding to the common area A2, and generates the misalignment check image P2 with the remaining area as a black mask area.

[0074] 10, the processing unit 34 performs a known extraction process for extracting, for example, a contour on the acquired captured image P1', thereby generating an edge-extracted image P4 (see FIG. 11) including a portion of an edge of the structure 42 in the captured image P1' (S34). Here, as shown in "S34" in FIG. 11, the processing unit 34 generates an edge-extracted image P4 including the contour of the structure 42 viewed from the front, the contours of each of the multiple windows 421 (see FIG. 9), and the contour of the doorway 422 (see FIG. 9).

[0075] 10, the processing unit 34 generates a test image P3 for each projection device 1 based on the misalignment check image P2 and the edge extraction image P4 (S35). Specifically, the processing unit 34 refers to coordinate correlation information that indicates the correlation between the coordinate system of the imaging device 2 and the coordinate system of the projection device 1, which is stored in advance in the storage unit 35, and converts each coordinate of the misalignment check image P2 and the edge extraction image P4 into the coordinate of the projection device 1, thereby generating the test image P3 from the misalignment check image P2 and the edge extraction image P4.

[0076] 11, the processing unit 34 generates a test image P31 for the projection device 1A and a test image P32 for the projection device 1B. The test image P31 is an image obtained by cutting out the first projection area A11 for the projection device 1A from each of the misalignment check image P2 and the edge extraction image P4 and combining them. The test image P32 is an image obtained by cutting out the second projection area A12 for the projection device 1B from each of the misalignment check image P2 and the edge extraction image P4 and combining them. That is, in the second embodiment, a portion of the structure 42, which is the target object 4, is depicted in the test image P3.

[0077] 10, the processing unit 34 outputs the generated test image P3 to each projection device 1 (S36), similar to step S15 in the first embodiment. Here, as shown in "S36" in FIG. 11, the processing unit 34 transmits test image P31 to projection device 1A and transmits test image P32 to projection device 1B. Then, when projection device 1A receives test image P31, it stores test image P31 in the storage unit 19. Also, when projection device 1B receives test image P32, it stores test image P32 in the storage unit 19.

[0078] As described above, in the image processing system 100A according to the second embodiment, a test image P3 in which a portion of the structure 42 is drawn is generated for each projection device 1, and the generated test image P3 is output to each projection device 1. Therefore, when a user wants to check whether there is a time-varying shift in the display position of images displayed by multiple projection devices 1, the user can more easily visually determine whether there is a shift in the projection area of ​​each projection device 1 by looking at the feature area (here, the common area A2) of each test image P3 projected onto the display surface 40 and a portion of the structure 42. This is because the portion of the structure 42 drawn in the test image P3 does not change over time, and therefore the user can more easily determine whether there is a shift in the projection area by comparing the portion of the actual structure 42 with the portion of the structure 42 in the image projected onto the display surface 40.

[0079] (Other embodiments) Although the first and second embodiments have been described above, the present disclosure is not limited to the first and second embodiments.

[0080] In the first and second embodiments, the image processing systems 100 and 100A calculate the common area A2 where the first projection area A11 of the projection device 1A and the second projection area A12 of the projection device 1B overlap as the characteristic area, but this is not limited to this. For example, if the first projection area A11 and the second projection area A12 do not overlap, that is, if there is no common area A2, the image processing systems 100 and 100A may calculate a distinctive pattern that can be distinguished from other parts in each of the first projection area A11 and the second projection area A12 as the characteristic area.

[0081] Specifically, if the target object 4 is a structure 42, the image processing system 100, 100A may calculate a portion of the structure 42 included in the first projection area A11 as the feature area corresponding to the projection device 1A, and may calculate a portion of the structure 42 included in the second projection area A12 as the feature area corresponding to the projection device 1B. In this manner, the user can determine whether or not there is a misalignment in the projection area by comparing a portion of the actual structure 42 with the feature area in the image projected on the display surface 40. Note that the above manner can also be applied to the case where there is a single projection device 1.

[0082] In the first and second embodiments, the image processing systems 100 and 100A transmit (output) the generated test image P3 to the projection device 1 for each projection device 1 and store the test image P3 in advance in the projection device 1, but this is not limiting. For example, the image processing systems 100 and 100A may store the generated test image P3 in the storage unit 35 for each projection device 1. Then, when the image processing systems 100 and 100A execute the process of checking the deviation over time, they may read out the test image P3 from the storage unit 35 for each projection device 1 and transmit (output) the read out test image P3 to the projection device 1.

[0083] In the first and second embodiments, the number of the multiple projection devices 1 is two. However, this is not limited to this, and the number of the multiple projection devices 1 may be three or more. For example, assume that the number of the multiple projection devices 1 is three, namely, a first projection device, a second projection device, and a third projection device, and that the first projection area of ​​the first projection device overlaps with the second projection area of ​​the second projection device, and that the second projection area of ​​the second projection device overlaps with the third projection area of ​​the third projection device. In this case, the processing unit 34 of the control device 3 may generate a test image P3 in which a predetermined pattern is drawn in a common area where the first projection area and the second projection area overlap, and output the test image P3 to the first projection device. The processing unit 34 may also generate a test image P3 in which a predetermined pattern is drawn in each of the common area where the first projection area and the second projection area overlap, and the common area where the second projection area and the third projection area overlap, and output the test image P3 to the second projection device. Furthermore, the processing unit 34 may generate a test image P3 in which a predetermined pattern is drawn in the common area where the second projection area and the third projection area overlap, and output the test image P3 to the third projection device.

[0084] For example, in the first and second embodiments, the video processing system 100 is realized by a single control device 3, but this is not limiting. For example, the video processing system 100 may be realized by a plurality of devices.

[0085] In addition, in the first and second embodiments, the processing performed by a specific processing unit may be performed by another processing unit. Also, the order of multiple processing operations may be changed, or multiple processing operations may be performed in parallel.

[0086] Furthermore, in the first and second embodiments, each component may be realized by executing a software program suitable for that component. Each component may be realized by a program execution unit such as a CPU or processor reading and executing a software program recorded on a recording medium such as a hard disk or semiconductor memory.

[0087] Furthermore, each component may be realized by hardware. Each component may be a circuit (or integrated circuit). These circuits may form a single circuit as a whole, or each may be a separate circuit. Furthermore, each of these circuits may be a general-purpose circuit or a dedicated circuit.

[0088] Furthermore, the general or specific aspects of the present disclosure may be realized as a system, an apparatus, a method, an integrated circuit, a computer program, or a computer-readable recording medium such as a CD-ROM, or may be realized as any combination of a system, an apparatus, a method, an integrated circuit, a computer program, and a recording medium.

[0089] The present disclosure may also be realized as a video processing method executed by a computer such as the video processing system 100 of the above-described Embodiments 1 and 2. The present disclosure may also be realized as a program (computer program product) for causing a computer to execute such a video processing method, or as a computer-readable non-transitory recording medium on which such a program is recorded.

[0090] In addition, this disclosure also includes forms obtained by applying various modifications to each embodiment that a person skilled in the art would think of, or forms realized by arbitrarily combining the components and functions of each embodiment within the scope that does not deviate from the intent of this disclosure.

[0091] (summary) As described above, in the image processing method according to the first aspect, for each of a plurality of projection devices 1 that project an image onto a display surface 40 of an object 4, a captured image P1 is acquired by capturing an image of the projection area projected by the projection device 1 using the image capturing device 2 (S10). In the image processing method, for each of the plurality of projection devices 1, a characteristic area that is a part of the projection area in the captured image P1 and has characteristics that can be distinguished from other parts is calculated (S12). In the image processing method, for each of the plurality of projection devices 1, a test image P3 is generated that includes the calculated characteristic area based on coordinate correlation information that indicates the correlation between the coordinate system of the image capturing device 2 and the coordinate system of the projection device 1, and that is projected onto the display surface 40 to check whether the projection area is deviated from the reference area (S14). In the image processing method, the generated test image P3 is output to the projection device 1 for each of the plurality of projection devices 1 (S15).

[0092] With this type of image processing method, if a user wants to check whether or not there has been a shift over time in the display position of images displayed by multiple projection devices 1, the user can project a test image P3 from each projection device 1 onto the display surface 40 and view the feature area of ​​each test image P3 projected onto the display surface 40. This allows the user to visually determine whether or not there has been a shift in the projection area of ​​each projection device 1, even if no geometric correction has been performed by each projection device 1. Therefore, this type of image processing method has the advantage of making it easy to detect a shift over time in the display position of images displayed by the projection devices 1.

[0093] Also, for example, in the image processing method according to the second aspect, in the first aspect, the characteristic area is a common area A2 where a plurality of projection areas projected by a plurality of projection devices 1 overlap.

[0094] With this type of image processing method, the user only needs to focus on the common area A2, which is the characteristic area, and therefore has the advantage that it is easier to visually determine whether or not there is a misalignment in the projection area compared to when focusing on the entire projection area.

[0095] Also, for example, in the image processing method according to the third aspect, in the first aspect, when the target object 4 is a structure 42, the characteristic region is a part of the structure 42 included in the projection region.

[0096] In such an image processing method, the part of the structure 42 that becomes the feature area does not change over time, and therefore, the user has the advantage that by comparing the part of the actual structure 42 with the feature area in the image projected on the display surface 40, the user can easily visually determine whether or not there is a deviation in the projection area.

[0097] Also, for example, in the video processing method according to the fourth aspect, in the second or third aspect, a predetermined pattern is drawn in the characteristic area of ​​the test image P3, and the remaining area in the test image P3 is a mask area drawn in a uniform color.

[0098] This type of image processing method has the advantage that the user can check whether there is any misalignment in the projection area of ​​each projection device 1 by looking only at the predetermined pattern projected onto the display surface 40 from each projection device 1, without having to look at the entire test image P3 projected onto the display surface 40.

[0099] Also, for example, in the video processing method according to the fifth aspect, in the fourth aspect, the predetermined pattern is a cross-hatching pattern.

[0100] This type of image processing method has the advantage that the user can easily grasp the extent to which the projection areas of each projection device 1 are misaligned by looking at the cross-hatched patterns projected onto the display surface 40 from each projection device 1.

[0101] Furthermore, for example, in the video processing method according to the sixth aspect, the colors of the lines of the predetermined pattern are different from each other in the plurality of test images P3 corresponding to the plurality of projection devices 1 in the fifth aspect.

[0102] Such an image processing method has the advantage that by looking at the color of the lines in a predetermined pattern, the user can easily visually determine whether the lines in the predetermined pattern are overlapping, i.e., whether there is a misalignment in the projection area.

[0103] Also, for example, in the video processing method according to the seventh aspect, in the sixth aspect, the combination of the color of a line of a predetermined pattern in any one of the multiple test images P3 and the color of a line of a predetermined pattern in another test image P3 is in a complementary color relationship.

[0104] In such an image processing method, when lines in a predetermined pattern overlap, they appear to be a different color from the color of the lines in the predetermined pattern, which has the advantage that the user can more easily visually determine whether the lines in the predetermined pattern overlap, i.e., whether there is a misalignment in the projection area.

[0105] Also, for example, in the video processing method according to the eighth aspect, in any one of the fourth to seventh aspects, if the object 4 is a structure 42, a part of the structure 42 is further drawn in the test image P3.

[0106] In such an image processing method, the portion of the structure 42 depicted in the test image P3 does not change over time, and therefore the user can more easily visually determine whether or not there is a misalignment in the projection area by comparing a portion of the actual structure 42 with a portion of the structure 42 in the image projected onto the display surface 40.

[0107] Furthermore, for example, in a video processing method according to a ninth aspect, a captured image P1 is acquired by capturing an image of a projection area on the display surface 40 of an object 4, where the image projected by a projection device 1 projects an image onto the display surface 40. The video processing method calculates a feature area that is part of the projection area in the captured image P1 and has features that can be distinguished from other parts. The video processing method generates a test image P3 that includes the calculated feature area based on coordinate correlation information that indicates the correlation between the coordinate system of the imaging device 2 and the coordinate system of the projection device 1, and that is projected onto the display surface 40 to check whether the projection area is deviated from the reference area. The video processing method outputs the generated test image P3 to the projection device 1.

[0108] With this type of image processing method, if a user wants to check whether or not there has been a shift over time in the display position of an image by the projection device 1, the user can project a test image P3 from the projection device 1 onto the display surface 40 and look at the feature area of ​​the test image P3 projected onto the display surface 40. This allows the user to visually determine whether or not there has been a shift in the projection area of ​​the projection device 1, even if geometric correction has not been performed by the projection device 1. Therefore, this type of image processing method has the advantage of making it easy to detect a shift over time in the display position of an image by the projection device 1.

[0109] Also, for example, a program according to a tenth aspect causes one or more processors to execute the video processing method according to any one of the first to ninth aspects.

[0110] With such a program, if a user wants to check whether there is a shift over time in the display position of images displayed by multiple projection devices 1, the user can project test image P3 from each projection device 1 onto display surface 40 and view the feature area of ​​each test image P3 projected onto display surface 40. This allows the user to visually determine whether there is a shift in the projection area of ​​each projection device 1, even if geometric correction has not been performed by each projection device 1. Therefore, such a program has the advantage of making it easy to detect a shift over time in the display position of images displayed by the projection devices 1.

[0111] Furthermore, for example, image processing systems 100, 100A according to an eleventh aspect include a communication unit 33 capable of communicating with each of a plurality of projection devices 1 that project images onto a display surface 40 of an object 4 and an imaging device 2 that captures the display surface 40, and a processing unit 34. For each of the plurality of projection devices 1, the processing unit 34 acquires a captured image P1 of the projection area projected by the projection device 1 using the imaging device 2. For each of the plurality of projection devices 1, the processing unit 34 calculates a feature area that is part of the projection area in the acquired captured image P1 and has features that can be distinguished from other parts. For each of the plurality of projection devices 1, the processing unit 34 generates a test image P3 that includes the calculated feature area based on coordinate correlation information that indicates the correlation between the coordinate system of the imaging device 2 and the coordinate system of the projection device 1. The test image P3 is projected onto the display surface 40 to check whether the projection area deviates from the reference area. The processing unit 34 outputs the generated test image P3 to each of the plurality of projection devices 1 (S15).

[0112] In such image processing systems 100, 100A, if a user wants to check whether or not there is a shift over time in the display position of images displayed by multiple projection devices 1, the user can project test images P3 from each projection device 1 onto the display surface 40 and view the feature areas of each test image P3 projected onto the display surface 40. This allows the user to visually determine whether or not there is a shift in the projection areas of each projection device 1, even if geometric correction has not been performed by each projection device 1. Therefore, such image processing systems 100, 100A have the advantage of making it easy to detect a shift over time in the display position of images displayed by the projection devices 1. [Industrial Applicability]

[0113] The image processing method and the like of the present disclosure can be used in a system that corrects the deviation of the display position of an image projected on a display surface such as a screen. [Explanation of symbols]

[0114] 100,100A Video Processing System 1, 1A, 1B Projection device 11 Video input section 12 Image generation unit 13 Video composition / selection section 14 Image adjustment section 15. Video projection unit 16 Input section 17 Communications Department 18 Control Unit 19 Memory section 2. Imaging device 3. Control device 31 Input section 32 Screen display section 33 Communications Department 34 Processing section 35 Storage section 4. Object 40 Display surface 41 screens 42 Structures 421 Window 422 Entrance / Exit A11 First projection area A12 Second projection area A2 Common area A21 area A31 1st common area A32 2nd common area P1, P1' captured images P2 Image for checking misalignment P31, P32, P3 test images PP1 Pattern Image SP1 Minutiae P4 Edge extraction image

Claims

1. For each of a plurality of projection devices that project an image onto a display surface of an object, a captured image is obtained by capturing an image of a projection area on a display surface of an object that is occupied by an image projected by the projection device using an imaging device; calculating a feature area that is a part of the projection area in the acquired captured image and has features that can be distinguished from other parts; generating a test image including the calculated feature area based on coordinate correlation information indicating the correlation between the coordinate system of the imaging device and the coordinate system of the projection device, the test image being projected onto the display surface to check whether the projection area is misaligned from a reference area; outputting the generated test image to the projection device; Image processing method.

2. the characteristic area is a common area where a plurality of projection areas projected by the plurality of projection devices overlap; The video processing method according to claim 1 .

3. When the object is a structure, the feature area is a part of the structure included in the projection area. The video processing method according to claim 1 .

4. In the test image, a predetermined pattern is drawn in the feature region, and the remaining region in the test image is a mask region drawn in a uniform color. The video processing method according to claim 2 .

5. The predetermined pattern is a cross-hatching pattern. The video processing method according to claim 4 .

6. In the plurality of test images respectively corresponding to the plurality of projection devices, the colors of the lines of the predetermined pattern are different from each other; The video processing method according to claim 5 .

7. a combination of a color of the line of the predetermined pattern in any one of the plurality of test images and a color of the line of the predetermined pattern in another test image has a complementary color relationship; The video processing method according to claim 6.

8. If the object is a structure, a part of the structure is further depicted in the test image. The video processing method according to claim 4 .

9. a projection device projects an image onto a display surface of an object, and an image capturing device captures an image of a projection area on the display surface that is occupied by the image projected by the projection device; calculating a feature area that is a part of the projection area in the acquired captured image and has features that can be distinguished from other parts; generating a test image including the calculated feature area based on coordinate correlation information indicating the correlation between the coordinate system of the imaging device and the coordinate system of the projection device, the test image being projected onto the display surface to check whether the projection area is misaligned from a reference area; outputting the generated test image to the projection device; Image processing method.

10. one or more processors, Executing the video processing method according to any one of claims 1 to 9, program.

11. a communication unit capable of communicating with each of a plurality of projection devices that project images onto a display surface of an object and an imaging device that images the display surface; a processing unit, The processing unit, for each of the plurality of projection devices, a captured image is obtained by capturing an image of a projection area on a display surface of an object that is occupied by an image projected by the projection device using an imaging device; calculating a feature area that is a part of the projection area in the acquired captured image and has features that can be distinguished from other parts; generating a test image including the calculated feature area based on coordinate correlation information indicating the correlation between the coordinate system of the imaging device and the coordinate system of the projection device, the test image being projected onto the display surface to check whether the projection area is misaligned from a reference area; outputting the generated test image to the projection device; Video processing system.

Images