JP5488624B2 - Video output device and video output method - Google Patents

Description

  The present invention relates to a video output apparatus and a video output method suitable for use in, for example, a video device having a picture-in-picture function.

  Currently, a large number of video devices that output video such as projectors and liquid crystal plasma televisions are in widespread use. Video equipment has become capable of supporting various types of video sources (personal computers, DVD players, high-definition televisions) as the day goes by. Further, with the increase in the screen size of video equipment, it is no exaggeration to say that a picture-in-picture function that simultaneously outputs a sub-screen video as part of the parent screen video is essential.

  In relation to this, for example, Japanese Patent Application Laid-Open No. H11-228688 corresponds to a scan conversion scanning line for the purpose of preventing deterioration of a sub-picture signal (small-screen video) when a picture-in-picture processed signal is scan-converted. A technique is described in which a frame memory for a plurality of frames is provided and a sub-video signal is directly written in the frame memory.

Japanese Patent Laid-Open No. 10-51687

  However, when the picture-in-picture function simultaneously outputs the sub-screen video to a part of the main-screen video, the video method of the sub-screen video is different from the main-screen video, and the frame frequency between them is different. The frame timing of the output video (display video) is synchronized with the frame timing of the main screen video, and a synchronization shift inevitably occurs in the frame timing of the sub screen video (see FIG. 7). Therefore, in the above case, tearing occurs in the sub-screen portion of the output video, that is, the upper part of one of the preceding and following frames is displayed at the same time as the lower part of the other frame, causing a phenomenon that the image is shifted vertically. However, such tearing cannot be solved even by the technique described above. The tearing can be eliminated by matching the frame timing of the output video to the frame frequency of the sub-screen video. In this case, however, there is a problem that tearing occurs in the parent screen video.

The present invention, such conventional has been made in view of the problems, the image output apparatus can output a more satisfactory display images for use for business, and a video output method, are used for their realization The purpose is to provide a program.

In order to solve the above-mentioned problem, in the invention of claim 1, a video output device that generates a single display moving image in which a display area for each input moving image is secured from a plurality of input moving images and outputs the generated display moving image. in a determination unit for changing the contents between frames to determine the highest input moving among said plurality of input video, synchronization to synchronize the frame frequency of the display video on either a frame frequency of said plurality of input moving And setting means for setting an input moving image determined by the determining unit as the largest change among the plurality of input moving images as a synchronization target to be synchronized with a frame frequency of a display moving image by the synchronizing unit. It was assumed.

Further, in the invention of claim 4, in the video output method of generating a single display image in which the display region of each input image is secured by a plurality of input video, and outputs the generated display image, said plurality A determination step of determining an input video having the largest change in content between frames among the input video of the input video, and an input video determined to have the largest change by the determination step among the plurality of input videos. The method includes a setting step of setting as a frame frequency synchronization target in the video and a synchronization step of generating the display video in synchronization with the set frame frequency of the input video.

According to a fifth aspect of the present invention, there is provided a computer having a video output device that generates a single display video in which a display area for each input video is secured from a plurality of input videos and outputs the generated display video. A determination process for determining an input video having the largest change in content between frames among the plurality of input videos; and an input video for which the change is determined to be the largest by the determination process among the plurality of input videos. and a program to be executed and setting processing to set as the synchronization target frame frequency of the display image, and a synchronization process to generate the display image in synchronism with the frame frequency of the input video set.

  As described above, according to the present invention, the display area of the display video in which tearing occurs when the frame frequencies of a plurality of input videos are different can be changed according to a predetermined selection rule. Therefore, when a plurality of videos having different frame frequencies are output at the same time, it is possible to output a better display video for the user.

It is a block diagram of the projector common to each embodiment. It is a block diagram which shows the detail of the image processor in 1st Embodiment. It is a flowchart which shows the processing content of CPU. It is a flowchart which shows a frame lock process. It is the figure which showed the setting menu of the picture in picture function. It is a figure which shows the relationship of the frame timing in an output frame, a parent frame, and a child frame. It is a figure which shows the example of tearing which arises on a subscreen. It is a figure which shows the relationship between the magnitude | size of a child screen, the screen area | region where tearing produces, and the position of a frame boundary. It is a block diagram which shows the detail of the image processor in 2nd Embodiment. It is a conceptual diagram which shows the operation | movement content of the 1st and 2nd moving image detection block, Comprising: It is the figure which illustrated the case where an input image | video is a still image etc. It is a conceptual diagram which shows the operation | movement content of the 1st and 2nd moving image detection block, Comprising: It is the figure which illustrated the case where an input image | video is a moving image. It is the figure which showed the setting menu of the picture in picture function. It is a flowchart which shows the processing content of CPU. It is a figure which shows the relationship between the difference of an input image | video, the screen area | region where tearing occurs, and the position of a frame boundary.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a block diagram showing a schematic configuration of a projector according to the present invention and common to the respective embodiments. This projector is compatible with two types of analog video signals of different methods and has a picture-in-picture function, and has the following configuration.

  That is, the projector has a two-channel input system, and the first and second A / D converters 1 and 2 for digitally converting the first and second analog video signals (input video) input to each channel, respectively. It has.

  The first and second digital video signals digitally converted by the first and second A / D converters 1 and 2 are sent to the image processor 3.

  The image processor 3 combines the input first and second digital video signals when the picture-in-picture function is used, deformation processing such as enlargement / reduction and trapezoidal distortion correction for the combined video data, setting menu screen, etc. (The details will be described later), and the processed video signal (digitally modified video signal) is output to the projection processing LSI 4.

  The projection processing LSI 4 drives the projection device 5 based on the gradation information for each pixel included in the input digital modified video signal. The projection device 5 of the present embodiment is an image conversion element including a micromirror array, and the projection processing LSI 4 converts gradation information for each pixel into a mirror control signal, and drives the projection device 5 by the mirror control signal. . The projection device 5 can be replaced with another image conversion element such as a transmissive liquid crystal shutter.

  The projection device 5 is driven by the mirror control signal and changes the reflection angle of the beam light source having a constant light amount from the lamp unit 6 for each mirror (pixel) to control the image light amount of each pixel to generate image light. Then, the image light generated by the projection device 5 is diffused by the optical lens 7 so that the input image or the synthesized image is projected onto an arbitrary screen as a projection image (display image).

  The basic operation of the image processor 3 is controlled by the CPU 8. The CPU 8 controls the entire projector according to a control program stored in the program memory 9. The control program includes a program that causes the CPU 8 to function as the synchronization means, setting means, selection control means, confirmation means, and setting control means of the present invention.

  The program memory 9 is a flash memory or the like in which stored data can be rewritten. In addition to the control program, setting data relating to various operation contents including operations relating to a picture-in-picture function in a projector that can be changed by the user is stored. Has been.

  A key block (KEY) 10 is connected to the CPU 8. A key block (KEY) 10 includes a plurality of operation keys used when the user operates the projector and sets basic operations, that is, a power key, a zoom key, up / down / left / right keys, and an AFK (automatic focus and keystone correction) key. , Input switching keys, menu keys, decision keys, and the like, and the operation state of the keys is regularly scanned by the CPU 8.

  FIG. 2 is a block diagram showing details of the image processor 3 described above. As shown in the figure, the image processor 3 mainly includes first and second input timing control blocks 11 and 12 corresponding to input channels, a frame image memory 13, an output input timing control block 14, a scaling block 15, an OSD (On Screen). Display) block 16.

  The first and second input timing control blocks 11 and 12 determine the frame start timing of the digital video signal in each input channel, and the digital video according to the setting contents (register values) of the control registers 11a and 12a in the block. Video data of a predetermined range (projection range) in the signal is stored at a predetermined address in the frame image memory 13. At that time, a timing signal indicating the frame start timing is output to the output input timing control block 14.

  The output input timing control block 14 synchronizes with the digital video signal of one of the input channels based on any one of the timing signals sent from the first and second input timing control blocks 11 and 12 at regular intervals. Video data (frame images) stored in the frame image memory 13 are sequentially extracted and output to the scaling block 15. At this time, the digital video signal to be synchronized is determined by the setting contents (register value) of the control register 14a in the block.

  The scaling block 15 arranges the input video data according to the setting contents (register value) of the control register 15a in the block, and generates display video data by performing deformation processing such as enlargement / reduction and trapezoidal distortion correction. The generated video data is output to the OSD block 16.

  The OSD block 16 overlays a set menu, its submenu, characters, and the like as necessary on the input video data after the deformation processing according to a command of the CPU 8, and then outputs it to the projection processing LSI 4.

  3 and 4 are flowcharts showing the operation contents of the CPU 8 according to the present invention. In this flowchart, a picture-in-picture (P-IN-P) setting menu (see FIG. 5), which will be described later, is displayed from a setting menu that is OSD-displayed on the projection screen by operating the menu key described above. This is the operation when setting the in-picture function.

  The CPU 8 controls the OSD block 16 in accordance with a predetermined key operation by the user, and causes the P-IN-P setting menu 101 shown in FIG. 5 to be OSD displayed on the projection screen (step SA1).

  As shown in the drawing, the P-IN-P setting menu 101 includes setting contents for four types of setting items of “sub-screen input source”, “sub-screen size”, “sub-screen position”, and “frame lock priority”. This is an option type sub-menu for selecting. “Sub-screen input source” relates to an input channel of video to be displayed on the sub-screen, and options are “input 1” or “input 2”. “Sub-screen size” relates to the display size of the sub-screen, and there are five options from “minimum” to “maximum”. “Sub-screen position” is a position for displaying a sub-screen, and is arbitrary. “Frame lock priority” is a synchronization target of the frame rate in the output video, and there are three choices: “parent screen”, “child screen”, and “area”.

  Then, the CPU 8 appropriately changes the selection state of the setting contents in accordance with the user's key operation (step SA2), and when the setting operation is ended by re-operation of the menu key or the like (YES in step SA3), P-IN- The display of the P setting menu 101 is terminated (step SA4), and the new setting contents are stored in the program memory 9. That is, the existing setting data is updated (step SA5). Thereafter, the frame lock process shown in FIG. 4 is executed based on the new setting contents (step SA6). Actually, processing other than the frame lock processing is also executed, but the description is omitted here for convenience.

  In the frame lock process, the CPU 8 first confirms the setting content related to “frame lock priority” (step SA101). Here, when the setting content is “parent screen”, the frame lock screen (synchronization target etc.) is determined as the parent screen (step SA102), and when the setting content is “child screen”, The frame lock screen is determined as a child screen (step SA103).

  In addition, when the setting content is “area”, the effective area (substantial display area) of the parent screen and the child screen on the projection screen based on the setting content of the “child screen size” described above. Is confirmed (step SA104). If the effective area of the parent screen is larger than that of the child screen, the frame lock screen is determined as the parent screen (step SA105). Conversely, if the effective area of the child screen is greater than or equal to the parent screen, the frame lock screen is determined as the child screen. Is determined (step SA106). In the present embodiment, when the setting content of “child screen size” is “large” or “maximum”, the effective area of the child screen is larger than the parent screen.

  Subsequently, the control register 14a of the output input timing control block 14 in the image processor 3 described above (see FIG. 2) based on the determined contents of the frame lock screen and the set contents of the “child screen input source”. The input channels to be synchronized (frame lock) are set as follows.

  That is, when the frame lock screen is the parent screen (step SA107 is “parent screen”) and “input 1” is set as the “sub-screen input source” (“input 1” in step SA108), the control register If “input 2” is set in 14a (step SA109) and “input 2” is set as “sub-screen input source” (“input 2” in step SA108), “input 1” is set in the control register 14a. Is set (step SA110).

  When the frame lock screen is a child screen (step SA107 is “child screen”) and “input 1” is set as the “child screen input source” (“input 1” in step SA111), the control is performed. If “input 1” is set in the register 14a (step SA112), and “input 2” is set as the “sub-screen input source” (“input 2” in step SA1111), “input 2” is set in the control register 14a. "Is set (step SA113).

  As described above, in the projector, when using the picture-in-picture function, if the frame rates of the two video images input to the projector are different, the user can select “frame” in the P-IN-P setting menu 101 as necessary. By selecting “parent screen” or “slave screen” as “lock priority”, the frame rate of the projected video is selectively synchronized with the frame rate of the video on the desired side of the parent screen or the slave screen (frame Can be locked).

  That is, FIG. 6 shows the relationship between the frame timing of the projected video frame (output frame) and the frame timing of the input video frame (parent frame) of the parent screen and the input video frame (child frame) of the child screen. FIG.

  If the frame lock target is the parent screen as shown in FIG. 5A, the output frame can be synchronized with the parent frame. However, in that case, since a synchronization shift inevitably occurs in the child frame, for example, tearing occurs in the child screen in the output frames indicated by [1] to [3] in the drawing. FIGS. 7A to 7C are diagrams showing examples of a small-screen image of the projected image 201 corresponding to the output frames [1] to [3]. If the frame lock target is a child screen as shown in FIG. 5B, the output frame can be synchronized with the child frame. In this case, however, the parent frame is inevitably out of synchronization. For example, tearing occurs in the parent screen in the output frames indicated by [4] to [7] in the figure.

  Therefore, the user can prevent the occurrence of tearing in the screen image on the more important side of the parent screen and the child screen by setting the frame lock target as the parent screen or the child screen as necessary. it can. As a result, it is possible to obtain a good projection image in which the tearing is not much concerned.

  In addition to the above, by selecting “Area” as “Frame Lock Priority” in the P-IN-P setting menu 101, the frame rate of the projected image is set to the side with the larger effective area of the parent screen or the child screen. Can be automatically synchronized (frame locked) with the frame rate of the video.

  That is, FIG. 8 shows the relationship between the difference in the setting of the “child screen size” described above, the screen area (parent screen or child screen) where tearing occurs in the projected image 201, and the position of the frame boundary in the frame where tearing occurs. FIG. 8A shows a case where the “child screen size” is “small”, FIG. 10B shows a case where the “child screen size” is “medium”, and FIG. It is the figure which illustrated the case where "small screen size" is "large."

  As is clear from this figure, if the user selects “Area” as “Frame lock priority”, it is effective when “Sub-screen size” is set to “Minimum”, “Small”, or “Medium”. It is possible to automatically prevent the occurrence of tearing on the parent screen whose area is larger than that of the child screen. When the setting value of “Child screen size” is “Large” or “Maximum”, the effective area is larger than that of the parent screen. Occurrence of tearing in a large child screen can be prevented.

  That is, it is possible to automatically prevent the occurrence of tearing in the screen image having the larger effective area between the main screen and the sub screen. As a result, the area where tearing occurs can be made as small as possible, and a good projected image with less noticeable tearing can be obtained.

  In the present embodiment, the case where the size of the sub-screen that can be set is limited to one of the five sizes prepared in advance has been described. (Including sizes having different aspect ratios) can be set. In that case, in the frame lock process described above, the effective area of the arbitrarily set sub-screen size is calculated immediately before step SA104, and then the calculation result is subtracted from the total area of the projected video to thereby calculate the parent screen. What is necessary is just to calculate an effective area.

  Unlike the present embodiment, for example, when there are three or more video input channels and the number of sub-screens that can be displayed in the picture-in-picture function is two or more, the steps described above are used. The comparison in SA104 may be performed using the sum of the effective areas of all the child screens as the effective area of the child screens.

(Embodiment 2)
Next, a second embodiment of the present invention will be described. In the present embodiment, in the configuration shown in FIG. 1, the above-described image processor 3 has the configuration shown in FIG.

  That is, in the present embodiment, the first and second moving image detection blocks 21 and 23 are provided after the first and second input timing control blocks 11 and 12, and the first and second moving image detection blocks are provided. First and second previous frame memories 22 and 24 are added to the blocks 21 and 23, respectively.

  The first and second previous frame memories 22 and 24 are memories that always hold video data (frame data) input to the first and second moving image detection blocks 21 and 23 at the previous frame timing.

  The first and second moving image detection blocks 21 and 23 are calculation means of the present invention, and the video data input from the first and second input timing control blocks 11 and 12 are respectively stored in the frame image memory 13. The following operation is performed.

  That is, the first moving image detection block 21 calculates the absolute difference between the luminance values of predetermined reference pixels for the video data input at the current frame timing and the previous video data held in the first previous frame memory 22. The luminance absolute difference as a value is calculated, and the accumulated result is output to the CPU 8. In the present embodiment, the reference pixels are pixels arranged in a predetermined specific line L (see FIGS. 10 and 11) in each video data. The first moving image detection block 21 stores the video data input at the current frame timing after the calculation in the first previous frame memory 22. Note that the second moving image detection block 23 operates in the same manner as the first moving image detection block 21.

  FIGS. 10 and 11 are conceptual diagrams showing the above-described operation contents in the first and second moving image detection blocks 21 and 23. FIG. 10A shows the video data 301 of the previous frame and its specific line. The luminance distribution of the pixels on L, (b) in both figures shows the video data 302 of the current frame and the luminance distribution of the pixels on the specific line L, respectively, (c) in both figures shows the previous frame It is the figure which showed the luminance absolute difference between this luminance distribution and the present flame | frame.

  FIG. 10 shows an example in which the input video data is video data of a still image (or a moving image in a substantially stationary state), and FIG. 11 shows an example in which the input video data is a moving image. . As illustrated, the absolute luminance difference is extremely small when the input video data is a still image or the like, and is large when the input video data is a moving image. In the case of a moving image, the larger the change between frames, the larger the absolute luminance difference.

  In the program memory 9, when setting the picture-in-picture function by the user, the CPU 8 notifies the CPU 8 of “frame” as shown in FIG. 12 instead of the setting menu 101 shown in FIG. 5. The setting menu 102 in which “moving image” is added to the “lock priority” option is displayed on the projection screen in an OSD manner, and the frame lock process shown in FIG. The program is stored. Other configurations are the same as those in the first embodiment.

  FIG. 13 shows the steps described in FIG. 3 when the user sets the picture-in-picture function from the setting menu 102 and the setting content related to “frame lock priority” is “moving image”. It is the flowchart which showed the frame lock process performed following SA1-step SA5.

  In the frame lock process, the CPU 8 confirms the cumulative result of the luminance absolute difference sent from the first and second moving image detection blocks 21 and 23, respectively (step SB101).

  Here, when the cumulative result sent from the first video detection block 21 is larger than the cumulative result sent from the second video detection block 23, the control register 14a of the output input timing control block 14 (FIG. 9). (Reference)), “input 1” (first input timing blocking block 11 side) is set as an input channel to be synchronized (frame lock) (step SB102).

  When the cumulative result sent from the first video detection block 21 is less than or equal to the cumulative result sent from the second video detection block 23, the control register 14a of the output input timing control block 14 is synchronized. “Input 2” (second input timing control block 12 side) is set as an input channel to be (frame locked) (step SB103).

  Thereafter, the processing of steps SB101 to SB103 is repeatedly executed until the setting content related to “frame lock priority” is changed to other than “moving image”. If it is set to other than “moving image”, the frame lock process shown in FIG. 4 is executed in the first embodiment.

  Thus, in the present embodiment, when the setting content related to “frame lock priority” is “video”, the frame rate of the projected video is always set regardless of the input video displayed on the parent screen and the sub-screen input video. The frame rate of the input video on the side where the change between frames is large can be synchronized (frame locked).

  That is, FIG. 14 shows a difference in input video, a screen area where a projection occurs in the projected video 201 (a parent screen or a child screen), and a tearing in the case where the setting contents of the “child screen size” are the same. It is a figure which shows the relationship with the position of the frame boundary in a flame | frame, Comprising: The same figure (a) has a larger accumulation result of the brightness | luminance absolute difference of "input 1" (1st input timing control block 11 side). In this case, FIG. 7B is a diagram illustrating cases where the cumulative result of the luminance absolute difference of “input 2” (on the second input timing control block 12 side) is larger. This relationship is the same even when the setting contents of “sub-screen position” are the same.

  Therefore, it is possible to automatically prevent the occurrence of tearing in the screen image on the side where the change between frames is large between the parent screen and the child screen, that is, the side where tearing is conspicuous. As a result, it is possible to obtain a good projection image in which tearing is not noticeable.

  In the present embodiment, the first and second moving image detection blocks 21 and 23 store the video data input at the previous frame timing in the first and second previous frame memories 22 and 24. The absolute luminance difference is calculated for each input video based on the previous frame video data and the current frame video data. However, the first and second previous frame memories 22 and 24 acquire the previous frame timing. Only the luminance information of the pixels arranged in the specified line L may be stored.

  In addition, the absolute luminance difference of each input video is calculated using the pixels on the specific line in each input video as the reference pixel, but the pixels other than the pixels on the specific line, for example, pixels in a plurality of predetermined areas are referred to It may be a pixel. Further, the degree of change in content between frames for each input video may be confirmed based on image information other than the absolute luminance difference.

  Also, unlike the present embodiment, for example, in a configuration in which there are three or more video input channels and the number of sub-screens that can be displayed in the picture-in-picture function is two or more, As many second video detection blocks 21 and 23 and first and second previous frame memories 22 and 24 as the number of input channels are provided, and instead of the frame lock process of FIG. What is necessary is just to perform a lock process. That is, among the input images, the input image having the maximum accumulated absolute difference is confirmed, and the input channel is to be synchronized (frame-locked) with the control register 14a of the output input timing control block 14. Can be set as

  Further, in the first and second embodiments described above, the case where the present invention is applied to a projector having a picture-in-picture function has been described. However, the present invention provides a display area for each input video from a plurality of input videos. As long as it generates a single display video in which is secured and outputs the generated display video, it can be applied to various video devices other than a projector.

  In addition to a video device having a picture-in-picture function, the present invention can also be applied to a video device having a multi-screen display function for displaying a plurality of input videos in a predetermined divided area and displaying them simultaneously.

3 Image processor 4 Projection processing LSI
5 Projection device 8 CPU
DESCRIPTION OF SYMBOLS 9 Program memory 11 1st input timing control block 12 2nd input timing control block 13 Frame image memory 14 Output timing control block 14a Control register 15 Scaling block 16 OSD block 21 1st moving image detection block 23 2nd moving image detection Block 101 Setting menu 102 Setting menu 201 Projected video 301 Video data 302 Video data

Claims (9)

In a video output device that generates a single display video in which a display area for each input video is secured from a plurality of input videos , and outputs the generated display video ,
A determination means for determining an input video having the largest change in content between frames among the plurality of input videos ;
Synchronization means for synchronizing the frame frequency of the display moving image with any one of the plurality of input moving images ;
A setting unit configured to set an input moving image that is determined to have the largest change by the determination unit among the plurality of input moving images as a synchronization target in which a frame frequency of a display moving image is synchronized by the synchronization unit; A featured video output device. The determining means always determines an input moving image having the largest content change between frames among the plurality of input moving images , and the setting means is determined to have the largest change based on the determination by the determining means. 2. The video output apparatus according to claim 1, wherein the input moving image is continuously set as a synchronization target in which a frame frequency of the displayed moving image is synchronized by the synchronization unit. For each of the plurality of input moving images, an arithmetic means for calculating a difference between luminance values of reference pixels in a predetermined region of each of the plurality of input images between successive frames,
The determining unit determines an input moving image having the largest change in content between frames among the plurality of input moving images based on a difference in luminance value of each of the plurality of input moving images calculated by the calculating unit. The video output device according to claim 1, wherein: The calculation means calculates a luminance absolute difference that is an absolute value of a difference between luminance values of the reference pixels for each of the plurality of input moving images ,
The determining means determines an input moving image having the largest change in content between frames among the plurality of input moving images based on a luminance absolute difference of each of the plurality of input moving images calculated by the calculating means. 4. The video output apparatus according to claim 3, wherein   5. The video output device according to claim 3, wherein the reference image is a pixel arranged in a predetermined line of each of the plurality of input images between successive frames. 6. 6. The method according to claim 3, wherein the determination unit determines an input moving image having the largest change in content between frames among the plurality of input moving images from a cumulative result of differences in luminance values of the reference pixels. Or the video output device described. 7. The video output apparatus according to claim 1, wherein display areas for each of the input moving pictures in the display moving picture are a main screen area and a sub screen area secured by a picture-in-picture function. In a video output method for generating a single display video in which a display area for each input video is secured from a plurality of input videos, and outputting the generated display video ,
A determination step of determining an input video having the largest change in content between frames among the plurality of input videos ;
A setting step of setting the input moving image determined to have the largest change by the determining step among the plurality of input moving images as a frame frequency synchronization target in the display moving image ;
A synchronization step of generating the display moving image in synchronization with the frame frequency of the set input moving image ;
A video output method comprising: A computer having a video output device that generates a single display video in which a display area for each input video is secured from a plurality of input videos , and outputs the generated display video ,
A determination process for determining an input video having the largest change in content between frames among the plurality of input videos ;
A setting process for setting, as a synchronization target of a frame frequency of the display moving image , an input moving image determined to have the largest change by the determination process among the plurality of input moving images ;
A synchronization process for generating the display video in synchronization with the frame frequency of the set input video ;
A program that executes