JP4632836B2 - Image search device - Google Patents

Description

  The present invention relates to an image search apparatus that searches a recording position of a desired image for a recording medium on which images of a plurality of channels are recorded in a random order for each frame.

Conventionally, as shown in FIG. 1, a monitoring system in which a plurality of cameras (2) are connected to a multiplexer-compatible image recording / retrieval device (1) is known (see Patent Document 1).
In the monitoring system, the image recording / retrieval device (1) includes image input terminals of a plurality of channels (for example, 16 channels), and a camera (2) is connected to each image input terminal.
The image recording / retrieval device (1) switches the image input from the image input terminals of a plurality of channels in a predetermined order by the multiplexer function, and transfers the image signal from each camera (2) to a large-capacity recording medium, for example, a built-in hard disk Record on device.

Here, the channel switching by the image recording / retrieval device (1) can be performed in an arbitrary order depending on the setting of the user. As a result, for example, as shown in FIG. When images of a plurality of frames of 0, 1, 2, 3, 4, 5,... Are sequentially recorded, the channel (CH) of these frames is 1, 2, 1, 7, 7, 2,.・ ・ There may be an irregular order.
In addition, as shown in FIG. 10, image information including a channel number, a recording time, an address, and the like is added to the image data of each frame, and one image data block (46) is formed for each frame. An image data block (46) is recorded on the recording medium.

  In this way, in the process of recording images of a plurality of channels in a random order for each frame in a series of recording areas of the recording medium, as shown in FIG. ID0, ID1, ID2, ID3... Are assigned. Each index includes an index number, a recording time, an address, and other information as shown in FIG. 9, and one index data block (47) is formed by these pieces of information, and a series of index data blocks (47). Is recorded on the recording medium.

  FIG. 11 shows the data structure of the recording medium (4). A setting value area (41) for storing various setting values, an index recording area (42) for storing a series of index data blocks, An image recording area (43) for storing a series of image data blocks is provided.

  In the image recording by the image recording / retrieval apparatus (1), as shown in FIG. 7C, a normal recording area and a pre-recording area each consisting of a plurality of frames are alternately set. In this case, a series of frames is recorded only once and is not overwritten. However, the pre-recorded area is repeatedly overwritten as shown in the figure, and when an event (for example, an alarm) occurs. Then, so-called pre-alarm recording is executed to shift to recording for the next normal recording area.

In pre-alarm recording, the frame is overwritten in the pre-recording area and at the same time the index is overwritten. For example, in the example shown in FIG. 7, the index ID1 assigned when the frame number 10 is recorded is overwritten when the frame number 20 is recorded. However, since the frame with the frame number 30 is recorded in the normal recording area, the index ID1 is not overwritten when the frame with the frame number 30 is recorded.
JP 2004-128533 A [H04N7 / 18]

  By the way, in the conventional image recording / retrieval apparatus (1), as shown in FIG. 7B, a designated channel and a designated date and time are specified for a recording medium in which images of a plurality of channels are recorded in a random order for each frame. By inputting, it is possible to search for a frame recorded on an image of a designated channel and at a designated date and time or the date and time closest to the designated date and time.

In the conventional image search, first, a frame recorded at a specified date and time is searched for the image recording area (43) of the recording medium (primary search), and then the search range is set from the frame to the previous and subsequent frames. While enlarging, the frame of the designated channel is searched (secondary search).
As a result, when a frame that is an image of the designated channel and is recorded at the designated date and time or the date and time closest to the designated date and time is found, the image is reproduced from the frame in response to a user operation or automatically. Start and display the image on the monitor screen.

  However, in the image search by the conventional image recording / retrieval device (1), if the frame of the designated channel exists near the frame of the designated date and time found by the primary search, the secondary search is quickly performed. Thus, the target image is displayed in a short time, but if the frame of the designated channel exists at a position far from the frame of the designated date and time found by the primary search, the secondary search is performed. Long time is required. In some cases, the image of the designated channel may not be recorded on the recording medium.

  As a result, the user must wait for a long time until the image of the designated channel is displayed or until a message indicating that the image of the designated channel is not recorded on the recording medium is displayed. Even if the image is displayed, if the recording time of the image is far from the specified date and time, the image is not worth checking and the waiting time is wasted.

  Accordingly, an object of the present invention is to provide an image search apparatus that can search for a target image without spending unnecessary waiting time.

The first image retrieval apparatus according to the present invention targets a recording medium on which images of a plurality of channels are recorded in a random order for each frame, in accordance with input of a designated channel and a designated date and time. And the recording position on the recording medium of the frame recorded at the designated date and time or the date and time closest to the designated date and time,
A primary search means for searching for a recording position of a frame of an arbitrary channel recorded on the designated date and time or the date and time closest to the designated date and time based on the inputted designated date and time;
Secondary search means for searching for the recording position of the frame of the designated channel within each search range while sequentially expanding the search range forward and backward around the recording position searched by the primary search means;
In the search process by the secondary search means, there is provided search range display means for displaying the front confirmation date and time and the backward confirmation date and time representing each search range on the monitor screen.

According to the image search device of the present invention, the forward confirmation date and time (search range start time) and backward confirmation date and time (search range end time) representing each search range in the search process by the secondary search means are displayed on the monitor screen. As a result, the user can recognize the progress of the search from both dates and times. As a result, the current search position is far away from the specified date and time, and the frame of the specified channel has been found after that. If it is determined that the image no longer needs to be confirmed, the search process can be forcibly stopped at that time.
As a result, useless waiting time can be avoided.

The second image retrieval apparatus according to the present invention is
In the process of recording an image of a plurality of channels on a recording medium, for each predetermined recording area composed of a plurality of frames, the representative frame identification data, the recording time of the frame, and the frame of each channel in each recording area Means for creating a channel information table that records a flag string indicating the presence or absence of
By referring to the channel information table based on the input designated date and time, the flag sequence for the recording area including the designated date and time is used as a starting point to search forward and backward flag sequences, Primary search means for searching a recording area in which a frame of a designated channel is recorded based on flag information included;
In the course of the search by the primary search means, the recording position on the recording medium of the frame that is the image of the designated channel and is recorded at the designated date and time or the date and time closest to the designated date and time for the searched recording area Secondary search means for searching for.

According to the image search apparatus of the present invention, the primary search is quickly performed because the primary search is performed by checking the flag stored in the channel information table. Then, since a highly accurate secondary search is executed for a predetermined recording area consisting of a plurality of frames found by the primary search, a long time is not required for the secondary search.
As a result, the target image is displayed on the monitor screen in a short time, and the waiting time of the user can be shortened.

  It should be noted that both the above-described search function (primary search and secondary search) of the first image search apparatus and the search function (primary search and secondary search) of the second image search apparatus are provided. The primary search and secondary search of the second image search device are executed, and when the target image is not found by this, the primary search and secondary search of the first image search device may be executed. It is valid.

  According to the image search device of the present invention, it is possible to search for a target image without spending unnecessary waiting time.

  Hereinafter, the embodiment in which the present invention is implemented in the monitoring system shown in FIG. 1 will be described in detail with reference to the drawings. As shown in the figure, a plurality of cameras (2) are connected to the image recording / retrieval apparatus (1), and multi-channel images taken by these cameras (2) are recorded in the image recording / retrieval apparatus (1). Are switched by the multiplexer function and recorded in the image recording / retrieval apparatus (1) as shown in FIG.

The image recording / retrieval device (1) includes a microcomputer and a hard disk device (both not shown) serving as a recording medium, and an image recording operation and an image retrieval operation are executed by the microcomputer.
Further, an image monitor is connected to the image recording / retrieval apparatus (1) when searching for an image, and the screen (3) shown in FIG. 2 is displayed on the monitor.

Note that the image recording / retrieval apparatus (1) is similar to the conventional case in the process of recording images of a plurality of channels in a random order for each frame in a series of recording areas of a recording medium, as shown in FIG. As shown, indexes ID0, ID1, ID2, ID3,... Are assigned at regular intervals (for example, every 10 frames).
Further, the image recording / retrieval apparatus (1) executes pre-alarm recording similar to the prior art as shown in FIG.

  FIG. 4 shows an image retrieval procedure executed by the image recording / retrieval apparatus (1) of the present invention. First, in step S1, a high-speed index search is executed. In step S2, it is determined whether the target image is found by the index search. When the target image is found, the search procedure is terminated and the target procedure is completed. If no image is found, a highly accurate all information search is executed in step S3.

When performing an index search, a channel information table (45) shown in FIGS. 3 (a) and 3 (b) is created in advance as part of the information of each index (47) during image recording.
The channel information table (45) is a block unit of a plurality (M) frames (10 frames in the example of FIG. 7) existing between two consecutive indexes, the index number ID (n), the index, The number N of the image (frame F) recorded synchronously, the recording time of the frame F (N) of the number N, and one frame block recorded immediately before the frame F (N), that is, the frame F (N−M) to F (N−1) include a flag string indicating whether or not a frame of each channel exists.

  As shown in FIG. 8, the channel information table (45) created by the image recording / retrieval device (1) includes a set area (41), an index recording area (42), and a recording area of the recording medium (4). The index recording area (42) is divided into image recording areas (43), and is composed of a collection of indexes (47) shown in FIG. 9, and one index (one index (1) (ID) as shown in FIGS. 47) is granted.

In the image recording / retrieval apparatus (1), since pre-alarm recording is performed as described above, the index (47) is also overwritten in the pre-recording area, and accordingly, the flag string in the channel information table (45) is also changed. It will be overwritten.
For example, for the frame blocks with frame numbers 0 to 9 shown in FIG. 7B, the index ID 1 is assigned when the frame number 10 is recorded. Since the channels of the frame numbers 0 to 9 are 1, 2, 1, 7, 7, 2, 1, 2, 3, 4 in order, the channel information table as shown in FIG. In (45), (1, 1, 1, 1, 0, 0, 1, 0, 0...) Is first stored as a flag string.

  However, in the process of recording the next frame number 10 to 19 by repetitive recording in the pre-recording area, the frame number 15 to 19 frame is overwritten on the frame number 8 to 12 image, and the frame 20 At the time of recording, the flag string in the channel information table (45) is also overwritten. As a result, as shown in FIG. 3B, for the index ID1, the flag string is rewritten to (0, 0, 1, 1, 1, 0, 0, 0, 0...).

However, in the process in which the next frame number 20-29 is recorded, the frame number 13-18 is erased by overwriting, but the frame number 26 is recorded in the next normal recording area when an event occurs. Since it is recorded, the flag string for index ID1 is not rewritten.
When the frame of frame number 30 is recorded, as shown in FIG. 3B, in the channel information table 45, the synchronous recording image, recording time and flag string (1, 1, 1, 1, 1) , 0, 0, 0...), And thereafter, similarly, the synchronous recording image, the recording time, and the flag string are stored for the indexes ID3, ID4, and ID5.

In the index search shown in FIG. 4, the target image is searched at high speed with reference to the channel information table (45) created as described above.
When searching for an image, the monitor screen (3) shown in FIG. 2 includes an input unit (31) for a target image channel (designated channel), and a date and time input unit (32) ) (33), forward confirmation date and time (start time of search range) and backward confirmation date and time (end time of search range) indicating the search range in all information search to be described later, and backward confirmation And a display unit (35) for the time obtained by subtracting the forward confirmation date and time from the date and time.

FIG. 5 shows a specific procedure for index search. In response to the input of the designated channel and the designated date and time on the monitor screen described above, first, in step S11, an index closest to the designated date and time is searched with reference to the channel information table (45) (primary search). For example, if the specified date is 10:30, index ID3 is found in the example of FIG.
Next, in step S12 in FIG. 5, a search is performed forward from the flag string for the index found by the primary search, and the search is performed backward in step S13.

  In the forward search of step S12, it is determined whether or not the flag of the designated channel is 1 in the flag string for the index found by the primary search. The frame nearest to the specified channel and the specified date and time is searched from the frame block before the frame number N of the frame, that is, the frames F (N−M) to F (N−1) (secondary search), and the image information ( X) is acquired.

If the flag of the designated channel is not 1 in the flag string for the index found by the primary search, the search proceeds to the immediately preceding flag string, and the flag of the designated channel is 1 in the flag string. If it is 1, the frame of the designated channel is searched from the frame block before the frame number N of the synchronous recording image of the index (secondary search), and the image information Get (X).
Thereafter, the forward search is executed in the same manner until the image information (X) of the designated channel is obtained. If no search is performed up to the last index in front, it is determined that there is no image information (X).

In the backward search in step S13, the search proceeds to the flag string immediately after the flag string for the index found by the primary search, and it is determined whether or not the flag of the designated channel is 1 in the flag string. If it is 1, the specified channel and the frame nearest to the specified date and time are searched from the frame block before the frame number N of the synchronously recorded image of the index (secondary search), and the image information (Y) is acquired. To do.
Thereafter, the backward search is executed in the same manner until the image information (Y) of the designated channel is obtained. If no search is made until the last index at the rear, it is determined that the image information (Y) is not present.

After that, in step S14, the acquisition status of the image information by the forward search and the backward search is determined, and when neither the image information X by the forward search and the image information Y by the backward search are acquired, the index search has failed. Complete the search as a thing.
When one of the image information X by the forward search and the image information data Y by the backward search is acquired, the acquired image information is retained and the search is completed.
When both the image information X by the forward search and the image information Y by the backward search are acquired, the process proceeds to step S15, and the image information closer to the designated date and time of the two image information X and Y is held. To complete the search.

  In the above-described index search, when the flag column of the channel information table (45) accurately indicates the presence of a channel, an accurate search is executed and a target image is found. As shown in (a) and (b), since the flag string is overwritten along with the pre-alarm recording, the flag string may not always reflect accurate channel information.

For example, in the example of FIG. 7 and FIG. 3B, the images of the frame numbers 0 to 7 remain, but the channel information (flag) for these images is stored in any index column of the channel information table (45). Is not left.
On the other hand, although the images of the frame numbers 10 to 18 do not remain, the channel information (flag) of these images remains in the index ID 1 of the channel information table (45).
Similarly, although the images of the frame numbers 34 to 37 do not remain, the channel information (flag) of these images remains in the index ID 3 of the channel information table (45). Further, although the images of the frame numbers 52 to 54 do not remain, the channel information (flag) of these images remains in the index ID 5 of the channel information table (45).

As described above, the flag column of the channel information table (45) may not represent accurate channel information. In such a case, there is a possibility that the index search will fail.
Therefore, in consideration of the case where the index search is unsuccessful, all information search is executed in step S3 of FIG.

  FIG. 6 shows a specific procedure for searching for all information. First, in step S21, the index recording area (42) of the recording medium (4) is searched for the front index closest to the designated date and time, and then in step S22, the recording medium (4 ) In the image recording area (43), the frame closest to the specified date and time is searched (primary search), and the image information of that frame is acquired.

Thereafter, in step S23, it is determined whether there is image information ahead, centering on the frame searched by the primary search means. If it is determined that there is information, the process proceeds to step S24, where With respect to the forward search range including a predetermined number of existing frames (for example, 5 frames), image information is sequentially read to search for an image that matches the designated channel.
In step S25, it is determined whether or not there is a channel matching image. If it is determined that there is no matching image, in step S26, the recording date and time of the first frame in the forward search range is set as the forward confirmation date and time. To display.

In step S23, it is determined that there is no information, or in step S26, the front confirmation date and time is displayed on the monitor screen. Then, the process proceeds to step S28, and the image is displayed backward with the frame searched by the primary search means as the center. It is determined whether information is present. If it is determined that the information is present, the process proceeds to step S29, and image information is sequentially read out for a backward search range including a predetermined number of frames (for example, 5 frames) existing behind. Search for an image that matches the specified channel.
In step S30, the presence / absence of a channel matching image is determined. When it is determined that there is no matching image, in step S31, the recording date / time of the last frame in the backward search range is set as the backward confirmation date / time. To display.

If it is determined in step S25 that there is a matching image, the image information of the image is acquired in step S27, and the search is completed. If it is determined in step S30 that a matching image exists, the image information of the image is acquired in step S32, and the search is completed.
For example, FIG. 7D shows a state in which the search range is expanded by 5 frames before and after the search range of frame numbers 26 to 30 when the specified time is 10:30, and all information search is being advanced. It represents.
In this way, when the target image is found by the index search and the all information search, the image data of the image is read in response to a user operation or automatically, and the image is displayed on the monitor screen.

  In the forward search in step S24 and the backward search in step S29, the search range is a predetermined number of frames, but may be a predetermined unit time range (for example, 1 hour).

  As described above, in the index search by the image recording / retrieval device (1) according to the present invention, a high-speed search is executed based on the channel information table (45) stored in the recording medium (4). The target image is displayed on the monitor screen in a short time, and the waiting time of the user can be shortened.

  Even if the target image is not found by the index search, a high-precision search is performed by the all-information search by the image recording / search apparatus (1). And the backward confirmation date and time are displayed on the monitor screen (3) as shown in FIG. 2, so that the user can recognize the progress of the search from both the date and time. Therefore, when the user determines that the current search position is far away from the designated date and time, and the frame of the designated channel is found after that, it is no longer necessary to confirm the image. It is possible to forcibly stop the search process. As a result, useless waiting time can be avoided.

  In addition, each part structure of this invention is not restricted to the said embodiment, A various deformation | transformation is possible within the technical scope as described in a claim. For example, the present invention is not limited to the monitoring system as shown in FIG. 1, and can also be implemented in an image recording apparatus that receives an image signal of multi-channel broadcasting and records it on a recording medium.

It is a figure which shows the apparatus structure of the monitoring system which concerns on this invention. It is a figure which shows the example of a display of a monitor screen. It is a figure which shows the storage data of a channel information table. It is a flowchart which shows the image search procedure of this invention. It is a flowchart which shows the specific procedure of an index search. It is a flowchart which shows the specific procedure of all information retrieval. It is a figure explaining the data recording system with respect to a recording medium. It is a figure explaining the data structure of a recording medium. It is a figure explaining the data structure of an index recording area. It is a figure explaining the data structure of an image recording area. It is a figure explaining the data structure of the recording medium in a conventional apparatus.

Explanation of symbols

(1) Image recording / retrieval device
(2) Camera
(3) Monitor screen
(4) Recording medium
(45) Channel information table

Claims (4)

For a recording medium on which images of multiple channels are recorded in a random order for each frame, according to the input of the designated channel and the designated date and time, the image is the designated channel and is closest to the designated date and time In an image search device for searching a recording position on a recording medium of a frame recorded at the time of day,
A primary search means for searching for a recording position of a frame of an arbitrary channel recorded on the designated date and time or the date and time closest to the designated date and time based on the inputted designated date and time;
Secondary search means for searching for the recording position of the frame of the designated channel within each search range while sequentially expanding the search range forward and backward around the recording position searched by the primary search means;
Search range display means for displaying a front confirmation date and time and a backward confirmation date and time representing each search range on the monitor screen in the search process by the secondary search means;
If the search range display means displays the forward confirmation date and time and the backward confirmation date and time representing each search range on the monitor screen, if a stop operation for stopping the search is performed, the search by the secondary search means An image search apparatus comprising: a cancel unit for canceling the image.   The search range display means displays a forward confirmation date and a backward confirmation date and time representing each search range on the monitor screen, and displays time data corresponding to a difference between the forward confirmation date and the backward confirmation date and time on the monitor screen. The image search device described in 1. For a recording medium on which images of multiple channels are recorded in a random order for each frame, according to the input of the designated channel and the designated date and time, the image is the designated channel and is closest to the designated date and time In an image search device for searching a recording position on a recording medium of a frame recorded at the time of day,
In the process of recording an image of a plurality of channels on a recording medium, for each predetermined recording area composed of a plurality of frames, the representative frame identification data, the recording time of the frame, and the frame of each channel in each recording area Means for creating a channel information table that records a flag string indicating the presence or absence of
By referring to the channel information table based on the input designated date and time, the flag sequence for the recording area including the designated date and time is used as a starting point to search forward and backward flag sequences, Primary search means for searching a recording area in which a frame of a designated channel is recorded based on flag information included;
In the course of the search by the primary search means, the recording position on the recording medium of the frame that is the image of the designated channel and is recorded at the designated date and time or the date and time closest to the designated date and time for the searched recording area And a secondary search means for searching for the image. For a recording medium on which images of multiple channels are recorded in a random order for each frame, according to the input of the designated channel and the designated date and time, the image is the designated channel and is closest to the designated date and time An image search apparatus for searching a recording position on a recording medium of a frame recorded at the time of day has a simple search means for performing a simple search and a detailed search means for performing a detailed search when a target frame is not found by the simple search. And simple search means
In the process of recording an image of a plurality of channels on a recording medium, for each predetermined recording area composed of a plurality of frames, the representative frame identification data, the recording time of the frame, and the frame of each channel in each recording area Means for creating a channel information table that records a flag string indicating the presence or absence of
By referring to the channel information table based on the input designated date and time, the flag sequence for the recording area including the designated date and time is used as a starting point to search forward and backward flag sequences, Primary search means for searching a recording area in which a frame of a designated channel is recorded based on flag information included;
In the course of the search by the primary search means, the recording position on the recording medium of the frame that is the image of the designated channel and is recorded at the designated date and time or the date and time closest to the designated date and time for the searched recording area Secondary search means for searching, and detailed search means,
A primary search means for searching for a recording position of a frame of an arbitrary channel recorded on the designated date and time or the date and time closest to the designated date and time based on the inputted designated date and time;
Secondary search means for searching for the recording position of the frame of the designated channel within each search range while sequentially expanding the search range forward and backward around the recording position searched by the primary search means;
An image search apparatus comprising: search range display means for displaying a forward confirmation date and time and a backward confirmation date and time representing each search range on a monitor screen in a search process by the secondary search means.

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