JP2007201866A - Video monitoring device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make visibility of additional information superposed on a monitoring video image excellent. <P>SOLUTION: A video monitoring device is provided which performs split allotment of each image obtained by video signals supplied from monitoring cameras 101-1 to 101-n respectively, into one image and superimposes the additional information on predetermined areas of each allocated image to display the additional information on a display device, and the video monitoring device is equipped with: a luminance level detection part 209 which divides the predetermined ares into blocks, calculates average values of luminance levels for each block and compares each average value of the luminance levels with a preset luminance level threshold; and an additional information composition part 205 which changes luminance levels and colors of the additional information to be superimposed in predetermined areas for each block. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a video monitoring apparatus, and more particularly to a video monitoring apparatus that superimposes additional information on a monitoring video so as to be visually recognized and displays the additional information on a display device.

  There are many video monitoring systems in which the monitor monitors the video by switching the monitor video captured by multiple monitoring cameras to, for example, a single monitor for monitoring, or by splitting and displaying the video simultaneously. It's being used. In this video monitoring system, when each video displayed on the monitor for monitoring is a video of which monitoring location, and when each video is video data recorded in a recording / reproducing apparatus, when that video is taken In order to present to the monitor whether or not it has been made, characters and date / time information such as the installation location of the surveillance camera and the shooting date / time are displayed in a superimposed manner for each video.

In such a video surveillance system, when the brightness of the installation location of the surveillance camera changes, the contrast between the captured video and the text / date / time information superimposed on the captured video also changes. Visibility is reduced. In order to solve such a problem, when the brightness of the background image changes, the average luminance value per frame of the entire screen is calculated, and the luminance level of the character information to be superimposed is calculated based on the average luminance value. A technique for adjustment is known (see, for example, Patent Document 1).
JP 2000-78470 A

  In the above-described video monitoring system, for example, video monitoring is performed in which one monitoring camera is installed in each of four monitoring locations with greatly different brightness, and the captured video is displayed on one monitoring monitor and the monitoring video is monitored. When the system is assumed, for example, in the case of displaying each monitoring video by switching four types of screens, the improvement technique described in Patent Document 1 can be applied. However, in the case where four monitoring images are simultaneously displayed on one screen by four-screen division processing, the method of calculating the average luminance value per frame of the entire screen described in Patent Document 1 cannot be expected to provide an appropriate effect. It had the problem that.

  Therefore, the present invention has been made in view of the above circumstances, and its purpose is to divide and allocate each image by a video signal supplied from a plurality of surveillance cameras installed in different places into one image. To provide a video monitoring device capable of maintaining good visibility of superposed information even if the brightness of each monitoring place changes when superimposing characters / date / time information, etc. It is.

In order to solve the above problems, the invention described in claim 1
Each image based on the video signal supplied from each of the plurality of monitoring cameras (101-1 to 101-n) is divided and assigned to one image (201), and additional information is superposed on a predetermined area of each assigned image. In the video monitoring device that poses (207, 205) and displays on the display device (103),
Block dividing means (209) for dividing the predetermined area of the one image into grid-like blocks;
Luminance average value calculating means (209) for calculating a luminance level average value for each block;
A brightness level comparing means (209) for comparing the calculated brightness level average value with a preset brightness level threshold value;
Luminance level changing means (210, 205) for changing the luminance level of the additional information superposed in the predetermined area for each block based on the comparison results;
An image monitoring apparatus (102) characterized by comprising
Is to provide.

The invention described in claim 2
Each image by the video signal supplied from each of the plurality of monitoring cameras (101-1 to 101-n) is divided and assigned to one image (201), and additional information is superposed on a predetermined area of each assigned image. In the video monitoring device that displays the pause (207, 205) on the display device (103),
Block dividing means (209) for dividing the predetermined area of the one image into lattice-like blocks;
Luminance average value calculating means (209) for calculating a luminance level average value for each block;
A brightness level comparing means (209) for comparing the calculated brightness level average value with a preset brightness level threshold value;
Color changing means (210, 205) for changing the color of the predetermined area for each block based on each comparison result;
An image monitoring apparatus (102) characterized by comprising
Is to provide.

  According to the present invention, when superimposing additional information by dividing and assigning each image based on video signals supplied from a plurality of surveillance cameras installed at different locations into one image, Even if the brightness changes separately, the luminance level and color of the additional information to be superimposed can be changed by determining in detail the luminance level of only a predetermined area of each image where the additional information is superimposed. Visibility can be kept good.

  The best mode for carrying out the present invention will be described below with reference to the drawings. First, FIG. 1 shows an overall configuration of a surveillance camera system to which a video surveillance apparatus as an embodiment of the present invention is applied. In the figure, the surveillance camera system 1 includes n (n is an integer of 2 or more) surveillance cameras 101-1 to 101 -n, a video surveillance device 102, and a display device 103.

  Each of the monitoring cameras 101-1 to 101-n is a video camera, and has a function of outputting a captured image as a video signal. In the present embodiment, the output video signal is an analog video signal.

  The video monitoring device 102 has a function as a control device of the monitoring camera system 1. In particular, the video signals respectively supplied from the monitoring cameras 101-1 to 101-n are encoded and then encoded and recorded on a built-in hard disk, and decoded or read from the hard disk. Decrypt data. Then, it has a function of superimposing character data of predetermined additional information, which will be described later, into decoded video and outputting video based on screen selection and screen division control. The display device 103 displays an image of the video signal supplied from the video monitoring device 102 (a monitoring video in which additional information is superimposed) on a monitor.

  Next, the internal configuration of the video monitoring apparatus 102 will be described based on the schematic functional block diagram of FIG. In the figure, an input signal processing unit 201 selects a maximum of n video signals coming from the monitoring cameras 101-1 to 101-n based on the control of the control unit 208, which will be described later, and converts them into digital signals. , Each of the n video signals is converted into a digital signal and divided and assigned to one screen, thereby generating a divided screen (for example, a 4-screen or a 16-screen).

  The encoding unit 202 has a function of encoding the digital signal supplied from the input signal processing unit 201. In this case, a known encoding method such as the JPEG method or the MPEG method can be applied to the encoding process, but in the present embodiment, the encoding method is based on the JPEG method.

  The recording unit 203 has a function of recording encoded data supplied from the encoding unit 202 via the control unit 208 and additional information supplied from the additional information management unit 207 described later via the control unit 208, A recording medium such as a hard disk or a memory can be applied. In this embodiment, a hard disk is used as a recording medium. The encoded data and additional information recorded in the recording unit 203 can be read out by the control unit 208.

  The decoding unit 204 encodes encoded data supplied from the input signal processing unit 201 via the encoding unit 202 and the control unit 208, or encoding read out from the recording unit 203 and supplied via the control unit 208. It has a function to decrypt data. Which encoded data is to be decoded is controlled by the control unit 208. The decoding method is a method capable of decoding corresponding to the encoding method of the encoding unit 202, and in this embodiment is the JPEG method.

  The additional information synthesis unit 205 is supplied with the decoded video signal decoded by the decoding unit 204 and is supplied with additional information managed by the additional information management unit 207 via the control unit 208 to generate character data. , And a function of superimposing character data on the supplied decoded video signal. The additional information combining unit 205 has a function of changing the luminance level of the character data based on the additional information and the color of the portion where the character data is combined, and a combining function with the decoded video signal.

  The signal output unit 206 has a function of outputting a decoded video signal in which character data is superimposed, and the output format thereof is, for example, an NTSC signal system based on analog or digital according to the input format of the display device 103, An RGB signal system and a color difference signal system can be applied.

  The additional information management unit 207 has a function of storing and managing information indicating the installation location of the monitoring cameras 101-1 to 101-n and shooting date / time information for each of the monitoring cameras 101-1 to 101-n. A user (monitoring person) of the monitoring camera system 1 can set information regarding the installation location of these monitoring cameras in a memory (not shown) provided in the additional information management unit 207 in advance. Further, the additional information management unit 207 includes a time measuring unit (not shown) for acquiring imaging date / time information.

  Based on the control of the control unit 208, the luminance level detection unit 209 converts one screen of the decoded video signal supplied from the decoding unit 204 into a plurality of grid blocks (for example, blocks of 8 × 8 pixels or 16 × 16 pixels). ), The average value of the luminance level is calculated for each block, compared with a preset luminance level threshold value, and the comparison result is output. In this case, the luminance level detection unit 209 may output the comparison result for all blocks constituting one entire screen, or a block corresponding to a preset area (this block portion includes character data based on additional information). May be output as a comparison result.

  Based on the comparison result of the blocks supplied from the luminance level detection unit 209, the additional information synthesis control unit 210 determines the luminance level of the character data to be superimposed by the additional information synthesis unit 205 and the block related to the portion where the character data is synthesized. It has a function of outputting a synthesis control signal for changing the color.

  And the control part 208 has a function which controls each part which comprises the video monitoring apparatus 102 as mentioned above.

  Next, the operation of the surveillance camera system 1 will be described. In the description of the operation of the present embodiment, an example in which four surveillance cameras 101-1 to 101-4 are connected will be described. In this example, it is assumed that the surveillance cameras 101-1 to 101-4 are respectively installed in the vicinity of an outdoor parking lot, in the vicinity of a badly lit daily street, in an office room, and in an underground warehouse room. . As described above, the brightness of the monitoring place where the monitoring cameras 101-1 to 101-4 are installed is not uniform due to the sunlight or illumination.

<4-screen split mode>
First, an example in which the video monitoring apparatus 102 divides the four screens of the four video signals supplied from the monitoring cameras 101-1 to 101-4 to the video monitoring apparatus 102 and displays them on the display apparatus 103 will be described. First, when the monitoring cameras 101-1 to 101-4, the video monitoring device 102, and the display device 103 are energized, each video signal starts to be supplied to the video monitoring device 102 from the monitoring cameras 101-1 to 101-4. The input signal processing unit 201 performs A / D conversion processing on each of the four video signals in response to the four-screen division control signal supplied from the control unit 208, and then performs four on a frame memory (not shown) for one screen. Divide the screen and map the video data. Since this video data mapping process can be realized by a known technique, a detailed description thereof will be omitted.

  Video data output from the input signal processing unit 201 (video data mapped in four divisions) is compressed by the encoding unit 202 by the JPEG method. The encoded data that has been subjected to data compression is recorded in the recording unit 203 as file data under the control of the control unit 208. At that time, information indicating the names of the four monitoring locations managed by the additional information management unit 207, date and time information acquired from the timing unit (collectively referred to as additional information) are multiplexed into the encoded data. Or linked to the recording unit 203.

  On the other hand, separately from the encoded data and additional information being recorded in the recording unit 203, the encoded data is supplied to the decoding unit 204 and decompressed by the JPEG method, and then added to the additional information combining unit 205 as decoded video data. And supplied to the luminance level detection unit 209.

  The luminance level detection unit 209 divides one screen of the supplied decoded video data into the plurality of blocks described above, calculates an average value of the luminance level for each block, and compares it with a preset luminance level threshold value. The comparison result is supplied to the additional information composition control unit 210. In this case, the luminance level detection unit 209 may output the comparison result for all the blocks constituting the entire screen, but outputs the comparison result only for the block corresponding to the data area where the character data is superposed later. It is preferable to do this.

  The additional information synthesis unit 205 generates a decoded video data supplied from the decoding unit 204 from a built-in character generator (not shown) based on the additional information supplied from the additional information management unit 207 via the control unit 208. Superimpose the character data to be played. At this time, a synthesis control signal for changing the luminance level of the character data at the time of superimposing and the color of the block corresponding to the portion where the character data is synthesized is added from the additional information synthesis control unit 210 to the additional information. The additional information combining unit 205 is supplied to the combining unit 205 and performs superimpose by converting the luminance level of the character data or the color of the character data combining block for each block based on the combining control signal.

  In the luminance level conversion process, for example, when the luminance level of the monitoring video is low at night or in a warehouse, the luminance level of the character data is converted to be high and superimposed. Further, when the luminance level of the surveillance video is high, such as in the daytime when the surveillance camera is installed in a backlight location, the luminance level of the character data is converted to be low and superimposed.

  In the color conversion process, when the luminance level of the block is high, the color is converted into a relatively dark color. When the luminance level of the block is low, the color is converted into a relatively bright color and superimposed.

  Then, the signal output unit 206 converts the superposed video data supplied from the additional information combining unit 205 into a format that can be displayed on the display device 103, outputs the converted data, and displays the converted data on the display device 103.

  The above description relates to a processing operation for encoding and decoding a video signal entering the input signal processing unit 201 in substantially real time and superimposing and displaying character data based on the additional information. The same processing is executed for the operation of reading the encoded data and the additional information recorded in the unit 203 to acquire the decoded video data and displaying it on the display device 103 through the superimpose processing.

  FIG. 3 shows a display example of the display device 103 in the 4-screen split mode. As shown in the figure, the monitoring images captured by the monitoring cameras 101-1 to 101-4 are displayed on the display device 103 as a four-divided screen. In this figure, the child screen at the upper left of the figure is a surveillance video near the outdoor parking lot imaged by the monitoring camera 101-1, and the child screen at the upper right of the figure is a surveillance video near the back street where the sun is badly lit, The sub-screen corresponds to the surveillance video of the office room, and the sub-screen at the bottom right of the figure corresponds to the surveillance video of the underground warehouse room. The two sub-screens on the upper left and upper right in the figure are examples displayed by changing the brightness level of the character data, and the two sub-screens on the lower left and lower right in the figure are in the area where the character data is combined. This is an example in which the color of the corresponding block is changed. As in this example, in the screen division mode, it is possible to control to change either the luminance level or the color for each child screen. Of course, it may be controlled to change both the luminance level and the color for each sub-screen.

<Single screen selection mode>
Next, an example in which the video monitoring device 102 selects one screen and displays it on the display device 103 for four video signals supplied from the monitoring cameras 101-1 to 101-4 to the video monitoring device 102 will be described. First, when the monitoring cameras 101-1 to 101-4, the video monitoring device 102, and the display device 103 are energized, each video signal starts to be supplied to the video monitoring device 102 from the monitoring cameras 101-1 to 101-4. The input signal processing unit 201 selects one video signal from the four video signals in response to the screen selection control signal supplied from the control unit 208, and performs A / D conversion processing on the selected video signal. The video data is stored in a frame memory (not shown). Subsequent processing is the same as in the above-described four-screen division mode, and thus description thereof is omitted.

  As described above in detail, according to this embodiment, each image based on the video signal supplied from each of the monitoring cameras 101-1 to 101-n installed at different locations is divided and added to one image. When superimposing character data based on information, even if the brightness of each monitoring location changes separately, the brightness level is detailed only in a predetermined area or in the whole of each image where the character data is superimposed By making the determination, it is possible to maintain good visibility by changing the luminance level and color of the character data.

  In addition, the same effect can be obtained in the case where the images by the video signals respectively supplied from the monitoring cameras 101-1 to 101-n are arbitrarily switched and displayed.

  In the present embodiment, the monitoring cameras 101-1 to 101-n are video cameras that output analog video signals, and these analog video signals are directly connected to the video monitoring device 102. The idea is not limited to this embodiment. For example, a plurality of monitoring cameras may be configured by network cameras and connected to the video monitoring apparatus via the network. In this case, it is preferable that the video captured by the surveillance camera is converted into encoded data such as JPEG data in the surveillance camera and supplied to the video surveillance apparatus.

It is the figure which showed the whole structure of the surveillance camera system to which the video surveillance apparatus as one Embodiment of this invention was applied. 1 is a schematic functional block diagram of a video monitoring apparatus as an embodiment of the present invention. FIG. It is the figure which showed the example of a display of the display apparatus in 4 screen division | segmentation mode of the video monitoring apparatus as one Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Surveillance camera system 101-1 to 101-n Surveillance camera 102 Image | video monitoring apparatus 103 Display apparatus 201 Input signal processing part 202 Encoding part 203 Recording part 204 Decoding part 205 Additional information synthetic | combination part 206 Signal output part 207 Additional information management part 208 Control unit 209 Luminance level detection unit 210 Additional information synthesis control unit

Claims (2)

In a video monitoring apparatus that divides and allocates each image based on video signals supplied from a plurality of surveillance cameras into one image and superimposes additional information on a predetermined area of each allocated image and displays it on a display device ,
Block dividing means for dividing the predetermined area of the one image into lattice blocks;
A luminance average value calculating means for calculating a luminance level average value for each block;
A brightness level comparing means for comparing each of the calculated brightness level average values with a preset brightness level threshold;
Luminance level changing means for changing the luminance level of the additional information to be superimposed in the predetermined area for each block based on each comparison result;
A video surveillance device comprising: In a video monitoring apparatus that divides and allocates each image based on video signals supplied from a plurality of surveillance cameras into one image and superimposes additional information on a predetermined area of each allocated image and displays it on a display device ,
Block dividing means for dividing the predetermined area of the one image into lattice blocks;
A luminance average value calculating means for calculating a luminance level average value for each block;
A brightness level comparing means for comparing each of the calculated brightness level average values with a preset brightness level threshold;
Based on each comparison result, color changing means for changing the color of the predetermined area for each block;
A video surveillance device comprising:

Images