JPH06295565A - Image processing method - Google Patents

Abstract

(57) [Summary] [Purpose] Perform image data search work that can be used in video tape editing work and plant monitoring systems without the need for large amounts of randomly accessible memory or advanced image processing. To provide a possible image processing method. A thinned image data obtained by thinning out image data stored in a first storage medium at regular intervals, and position information of the thinned image data on the first storage medium are randomly accessible. An image processing method, wherein the image data is stored in a second storage medium, and the image data on the first storage medium is searched from the thinned-out image data on the second storage medium and its position information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image suitable for video editing for retrieving and editing a necessary video image (image on video tape) from moving image data stored on a video tape or the like on an information processing device. More specifically, the present invention relates to an image processing method characterized in that the position of image data to be searched for is determined using image data in which images obtained by thinning out video images at regular intervals and digitized are stored in secondary storage. .

[0002]

2. Description of the Related Art Conventionally, when searching an edited portion from a video image, a video tape is searched from the beginning to specify a necessary scene. In this method, since the video tape cannot be randomly accessed, there is a drawback that fast-forwarding and rewinding must be performed, and it takes time to find a portion to be searched. On the other hand, it is conceivable to store the video image in a randomly accessible storage medium such as a hard disk and detect the necessary scene, but in this case, many images are stored in order to store all the images. However, there is a problem that the storage medium is required and the storage medium is more expensive than a video tape or the like. As a method for solving the above-mentioned problems, for example, there is a method disclosed in Japanese Patent Application Laid-Open No. 04-111181, "Method for detecting change point of moving image". This method calculates the feature amount including the color histogram in each frame of the moving image,
This is a method in which the correlation with the immediately preceding frame is obtained, and the correlation is compared with the correlation of the past frame to obtain the change rate, whereby a place with a large change rate is detected as a scene change. According to this method, image data can be extracted each time the scene changes, and the still image can be used to cue the video image for each scene.

[0003]

The above-mentioned prior art is a method of automatically detecting a scene change and using it for cueing image data. Therefore, it cannot be detected as a change unless the screen is greatly changed. , It is difficult to detect an image to be used for cueing from moving image data that does not change much in a scene. In addition, this processing method requires advanced image processing for extracting change points. Therefore,
There is a problem in that it takes a long time to perform a process of determining a frame required for the cue. Further, this processing method has a problem that it is not suitable for a surveillance system that continuously monitors the same object all day long when it is necessary to detect a slight change in image data. is there. The present invention has been made in view of the above circumstances, and an object of the present invention is to solve the above-described problems in the prior art and to use image data that can be used in videotape editing operations, plant monitoring systems, and the like. An object of the present invention is to provide an image processing method capable of executing the search operation of (1) without requiring a large amount of randomly accessible memory or advanced image processing.

[0004]

The above object of the present invention is to provide thinned-out image data obtained by thinning out image data stored in a first storage medium at regular intervals, and the first thinned-out image data. Position information on a storage medium is stored in a randomly accessible second storage medium, and image data on the first storage medium is searched from the thinned-out image data on the second storage medium and the position information. This is achieved by an image processing method characterized by:

[0005]

In the image processing method according to the present invention, the image data on the storage medium such as a video tape is thinned out at a constant interval to be associated with the original image data, and the secondary storage capable of random access is created. Store as a digital image. Then, the digital image on the secondary storage is used to determine a necessary portion on the video tape. Regarding the selection of the necessary image data, the operator's judgment is awaited. In the image processing method according to the present invention, not all image data is stored in the randomly accessible secondary storage, so a huge memory is not required, and a video tape for detecting specific image data is used. It is possible to reduce the detection work time by eliminating the trouble of searching in sequence from the beginning.

[0006]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a block diagram showing the hardware configuration of a video tape editing apparatus according to an embodiment of the present invention. In the figure, 11 is a processor for controlling each device, which operates according to a program stored in the program memory 20. Reference numerals 12 and 13 denote video devices for playing back and recording analog video images, and include a processor 1
Controls such as fast-forwarding and cueing from 1. Reference numeral 14 is an A / D converter for converting a video image into an analog / digital signal. The image input from the video device (1) 12 is thinned out at a constant interval to be digitized, and a frame memory 15 is provided.
To store. A secondary storage 16 stores the digital image in the frame memory 15 in association with the image data on the video tape in the video device (1) 12. This is randomly accessible, and a hard disk is used in this embodiment. A display device 17 displays a digital image through the frame memory 15 or a video image from the video device (1) 12. Also, 18, 19
Is a pointing device and an input device used for inputting a time interval for thinning out an image on a video tape and designating a desired one of still images displayed on the display device 17. Here, a pointing device and an input device are respectively used. I use the keyboard.

FIG. 2 is a flow chart showing the outline of the processing procedure of video tape editing in this embodiment. In step 21, the time A during which the image is recorded on the video tape in the video device (1) 12, the time interval B to be thinned when the video image is stored in the secondary storage 16 as a digital still image, and the still image. A size C of a video image when storing an image and a storage medium D for storing the still image are input from the input device 19 and designated. And step 22
Then, the remaining capacity is checked in order to know whether or not the still image can be stored in the secondary storage 16 according to the data designated in the above step 21. Here, it is assumed that the memory capacity is sufficient if the following formula is established. Remaining capacity of secondary memory 16> (Recording time A / time interval B) ×
Size of still image C × number of bits required for one pixel If this equation is satisfied and it is confirmed that the digitized still image can be stored in the secondary storage 16, step 23
Then, the analog signal recorded on the video tape in the video device (1) 12 is thinned out at every interval B in the video tape recording time A designated in step A to D / D.
Digitized by converter 14, and frame memory 15
Sequentially stored in the secondary storage 16 via.

When the above process is completed, in step 24 and step 25, the data to be searched for the image to be edited is input from the input device 19, and the still image stored in the secondary storage 16 is displayed accordingly. To do. Then, the time to start editing and the time to end editing are sequentially designated by the pointing device 18 and the input device 19 and stored in the memory 20. When the designation of the edited portion is completed, the video tape in the video device (1) 12 is searched at the start time by using the designated data in step 26,
(2) The video is recorded on the tape 13 and when the end time is reached, the video device (2) 13 is temporarily stopped and the video device (1) 12 is cued for the next start time. This is repeated until the data of the recording start time and the end time stored in the memory 20 is exhausted, and the video tape is edited. FIG. 3 is a detailed flowchart of the process of step 23, and is a flowchart of the operation of converting an analog image on a video tape into a digital image and storing it in a secondary storage. In step 31, the recorded portion of the video tape contained in the video device (1) 12 is searched for. At that time, the video tape counter set in the memory 20 is initialized. Further, as the header information for storing the still image in the secondary storage, the recording time A of the video tape, the thinning time interval B, and the memory capacity necessary for storing the still image of one screen are stored. Then, in the process of step 32, the first frame is digitized using the A / D converter 14 and stored in the frame memory 15.

Next, in step 33, the video tape is advanced by the time interval B. Meanwhile, in step 34, a still image is stored in the secondary storage 16 from the frame memory 15. When the processing of step 33 and step 34 is completed, step 35
Then, the video tape counter is incremented by the time interval B. In step 36, the total recording time A on the video tape is compared with the value of the video tape counter, and A
If is larger, the process returns to step 32. This process is repeated until the recording time A of the video tape ends. FIG. 4 is a diagram showing an example of a data structure when a still image is stored in the secondary storage 16. In the figure, 41 is a header for specifying the storage location 46 of the still image in the secondary storage 16, and 42 and 43 are the total recording time A and the time interval B designated in step 21. 44 is step 21
It is the size C for storing the still image designated in step 1 multiplied by the number of bits required for the digital image per dot. The still images digitally converted in step 23 are stored in the storage location 46 in order from the location pointed by the pointer 45. Here, since the memory amount required for a still image per frame is constant, if the relative value from the video tape start time is known, the still image stored in the storage location 46 is uniquely determined from the information of the header 41. be able to.

FIG. 5 is a diagram showing an example of a screen for designating the start time and the end time of editing the video tape, and shows the situation displayed on the display device 17. This is a detailed description of the processing in steps 24 and 25. In the figure, 51 is a display example of the screen, which indicates the time zone of the video image displayed in the input area 52,
The intervals of the still images displayed in the input area 53 are
Input is made using the pointing device 18 and the input device 19. Based on this input result, the still image designated in the display area 54 is read from the secondary storage 16 and an image for 6 screens is displayed. Next, with the mouse cursor 55, the pointing device 18 is used to designate a still image in a time zone that is desired to be seen more finely from the images of the six planes displayed in the display area 54. The screen shown in is displayed. The same operation as that described above is repeated on this screen to display still images at finer time intervals. If the interval specified in the input area 53 is smaller than the interval B specified in step 21, the videotape contained in the video device (1) 12 is rewound or fast-forwarded, and the moving image is displayed in the display area 54. To do. By repeating these operations, the position of the required moving image is confirmed, the recording start time or the end time is determined, and the input area 56 or 57 is input using the input device 19 and the pointing device 18.

For example, consider a case where the recording time A of the video tape is designated as 30 minutes and the time interval B for storing the still image is designated as 5 seconds in step 21. First, in the input area 52, the time zone to be displayed is 15 to 20 minutes, and in the input area 53,
The time interval is designated as every one minute (see FIG. 5 (a)). As a result, a still image is recalled from the secondary storage 16 every 15 minutes, and every 15 minutes, 16 minutes, 17 minutes, 18 minutes, 19 minutes, 2 minutes.
Six 0th screens are displayed in the display area 54 in order. Next, if the 16-minute portion is to be detailed, the 16-minute image is designated by the pointing device 18. And
After switching to the screen of display example 58, input area 5 should be displayed every 5 seconds from 16 minutes 20 seconds to 45 seconds.
9 and 510 are designated by the input device 19 (see FIG. 5B). If it is displayed on 511 as specified, from that,
512-second still image of 25 seconds near the image you want to edit
Specify using the pointing device with. Here, since still images are not stored in the secondary storage 16 in units smaller than 5 seconds, the display is moved to 16 minutes 25 seconds to display the moving image of the video device (1) 12. Then, a moving image for 5 seconds from there is displayed on 511. From that, the time to start editing is input in the input area 56. For the end time, the same processing is repeated and input in the input area 57. The above operation is repeated several times to set all editing times.

FIG. 6 is a flowchart showing a processing procedure for video editing according to the recording start time or end time designated in FIG. 5, and is a detailed description of step 26 in FIG. In step 61, the first recording start time is read out from the editing time index stored in the memory 20. According to the data, in step 62, the video tape in the video device (1) 12 is cued. When it is finished, in step 63, the video device (2) 13 with a tape for recording the edited video image.
Is set to a recordable state, the video device (1) 12 is reproduced, and dubbing is performed. In step 64, the recording end time is read out from the memory, and when it is equal to the time of the video tape of the video device (1) 12, the video device (2) 13 is suspended. The processing from step 62 to step 65 described above is performed until the index in the memory 20 containing the editing time data is completed. This step
The moving image edited according to the data designated by 25 is recorded on the video tape in the video device (2) 13. Through the above processing, video editing using the image processing method according to the present invention can be carried out.

In the above-mentioned embodiment, the example in which the present invention is applied to the video editing apparatus has been shown. Next, the present invention is applied to a monitoring apparatus for recording a moving image obtained from a video camera in the video apparatus. Is also applicable. FIG. 7 is a diagram showing a hardware configuration of a monitoring system according to another embodiment of the present invention. In the figure, symbols 11, 12 and 1
4 to 20 show the same components as those used in the above-mentioned embodiment. Reference numeral 71 is a camera for photographing. Figure 8
2 is a flowchart showing an outline of a processing procedure of the monitoring system according to the present embodiment. In step 81, a time interval B for thinning out a video image to be recorded for monitoring and storing it as a digital image, a size C for storing it as a still image, and a secondary memory D for storing the still image are designated. Then, in step 82, the camera 71 is operated to bring the video device (1) 12 into a recording state, and a video image obtained by monitoring the object is recorded. In the meantime, according to the time interval B, the thinned-out video image is converted into a digital image using the A / D converter 14, and the secondary storage 16 is performed via the frame memory 15.
To store. Repeat this for the time you want to monitor or all day. Next, when referring to the recorded video, in step 83, the due date and the time zone to be investigated are designated, and the still image between them is read from the secondary storage 16 and displayed on the display device 17.

In step 84, the still image in the time zone to be investigated in detail is designated by using the pointing device 18 or the input device 19, and the moving image in the designated time zone is designated by the video device (1) 12.
It is called from the video tape inside and displayed on the display device 17. FIG. 9 is a detailed description of the process of step 82 in FIG. 8, in which the image taken by the surveillance camera 71 is recorded on the tape in the video device 12 and at the same time the step is performed.
22 is a flowchart showing a process of storing a digital image in the secondary storage 16 according to the data designated by 81. In step 91, the surveillance camera 71 is operated and the video is recorded by the video device (1) 12. At that time, the secondary memory 16
Then, the due date and the time zone of the day are stored as header information of the still image. Next, in step 92, the first frame is A
The digital image is converted by the / D converter 14 and stored in the secondary storage 16 through the frame memory 15. When this process is completed, in step 93, the time counter for measuring the recording time of the video tape set in the memory 20 is reset. Then, in steps 94 and 95, the processing of steps 92 and 93 is repeated every time the counter reaches the time interval B specified in step 81 until the end time is reached.

FIG. 10 is a diagram showing an example of the data structure of the video image stored in the secondary storage 16 in step 82.
In the figure, 101 is a table showing the year of absolute time when a video image was recorded, 102 is a month, 103 is a day, 104 is a time, and 105 is a minute. Then, the minute table 105 is provided with a pointer indicating a place 106 where the digitized still image is stored. The still image is stored in the size C for each time interval B designated in step 81, and the amount of data used by each image is constant. Therefore, by tracing these, if the absolute time is specified, the still image at that time can be called. FIG. 11 is an example of a display screen when the time zone to be investigated on the surveillance video tape is set, and is displayed on the display device 17. This is step 83,
This is a detailed description of the process of step 84. 111
Is a display example of the first screen. In the input area 112, the time zone to be investigated by using the input device 19 and the pointing device 18 is designated in absolute time. Also, the input area 113
For, specify how often the still images in that time period should be displayed. According to this value, the display area 11
In 4, a still image read from the secondary storage 16 is displayed for 6 screens.

A scene desired to be seen in detail is designated by 115 using the pointing device 18. In accordance therewith, the display screen is switched from 111 to 116, and the time zones for newly displaying a still image are set in the input areas 112 and 113. By repeating this operation, the part where the necessary image is recorded is confirmed. When a moving image is to be displayed, the portion is designated by a pointing device at 117, and the moving image display is selected at 118. Then, when the screen is switched to the screen of 119, how long from that time the moving image is to be displayed is designated at 120. According to these designations, the video image recorded on the video tape of the video device 12 is cueed, and the moving image is displayed in the display area 121 for the time designated by 120 from that position. For example, in 112, “15 October 1992 15:
Consider the case of specifying "30". Next, if you specify to display every 2 minutes from 15:30, 15:30, 3
Still images of 2 minutes, 34 minutes, 36 minutes, 38 minutes, and 40 minutes are sent from the secondary storage 16 to the frame memory 15 and displayed on the display device 17 like a display screen 114. Here, if there is a still image at 15:34 that seems to have a necessary scene, it is clicked with the pointing device 18. As a result, the display screen is switched from 111 to 116, so that the input area 113 is set to display a still image at intervals of 30 minutes from 15 minutes 34 seconds.

By this designation, six still images are displayed in the display area 115 every 15 minutes 34 seconds to 30 seconds.
Here, if it is confirmed from the still image that the required moving image is around 15 minutes 34 seconds 30 seconds, the pointing device 1
That is designated by 8 and designated by 118 to display a moving image. Next, a screen for designating how many minutes to display on the display screen 119 is displayed.
Cue at 15:35 on October 15, 2nd, and display in the display area 121. After that, if you want to display it again, 122
Select to re-display with, and to end when you want to end. By this processing, it becomes possible to display the required portion of the moving image on the display device 17. In the present embodiment, the above processing makes it possible to improve the efficiency of the work for specifying the scene to be watched in the monitoring work such as plant monitoring. It is needless to say that each of the above embodiments is an example of the present invention and the present invention should not be limited to this.

[0018]

As described above in detail, according to the present invention, a large amount of randomly accessible memory or memory can be used for image data search work that can be used in video tape editing work or plant monitoring systems. This has the remarkable effect of realizing an image processing method that can be executed without requiring advanced image processing.

[Brief description of drawings]

FIG. 1 is a hardware configuration diagram of a video editing apparatus according to an embodiment of the present invention.

FIG. 2 is a flowchart showing an outline of the operation of the embodiment.

3 is a flowchart showing details of step 23 shown in FIG. 2. FIG.

FIG. 4 is a data structure when a still image is stored in a secondary storage.

FIG. 5 is a display example of a control screen of the video editing apparatus according to the embodiment.

FIG. 6 is a flowchart showing the operation of the embodiment.

FIG. 7 is a hardware configuration diagram of a monitoring system according to another embodiment of the present invention.

FIG. 8 is a flowchart of the operating procedure of the embodiment.

FIG. 9 is a flowchart showing the operation of the embodiment.

FIG. 10 is a data structure when a still image is stored in the secondary storage.

FIG. 11 is an example of a control screen of the monitoring system according to the embodiment.

[Explanation of symbols]

11: processor, 12: video device, 13: video device, 14: analog / digital converter, 15: frame memory, 16: secondary storage device, 17: display device,
18: pointing device, 19: input device, 20: memory, 61: camera.

Front page continuation (72) Inventor Akitsugu Nakamura 1099, Ozenji, Aso-ku, Kawasaki, Kanagawa Inside the Hitachi, Ltd. system development laboratory (72) Masanori Honda, 1099, Ozenji, Aso-ku, Kawasaki, Kanagawa Hitachi, Ltd. System Development Laboratory

Claims (6)

[Claims] 1. Random access is possible between thinned image data obtained by thinning out image data stored in a first storage medium at regular intervals and position information of the thinned image data on the first storage medium. Image processing method for storing the image data in the first storage medium on the basis of the thinned image data on the second storage medium and the position information thereof. 2. The thinning-out interval of image data for obtaining the thinned-out image data is determined by the remaining storage capacity of the second storage medium, the storage capacity required to store one image, and the total storage capacity in the first storage medium. The image processing method according to claim 1, wherein the time interval is determined based on the number of images. 3. The first storage medium is a first video tape, and a necessary image in the first video tape is set to a third image based on a search result by the image processing method according to claim 1. And a second video tape which is a storage medium of the above. 4. The image data sent from the image input device is stored in a first storage medium, and at the same time, the thinned image data obtained by thinning out the image data at a constant interval and the first thinned image data. The position information on the storage medium is stored in a second storage medium that is randomly accessible,
The image processing method for searching image data on the first storage medium from the thinned-out image data on the storage medium and position information thereof. 5. The thinning-out interval of image data for obtaining the thinned-out image data is determined by the remaining storage capacity of the second storage medium, the storage capacity required to store one image, and the total storage capacity in the first storage medium. The image processing method according to claim 4, wherein the time interval is determined based on the number of images. 6. The image input device is a video camera, and the first storage medium is a first video tape. Based on a search result by the image processing method according to claim 4 or 5, An image processing method characterized in that a necessary image in the first video tape is stored in a second video tape which is a third storage medium.