JP2012191387A - Image recording apparatus and retrieval and reproduction apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image recording apparatus and a retrieval and reproduction apparatus capable of recording and retrieving/reproducing an image including motion without needing an enormous amount of signal processing such as signal expansion processing.SOLUTION: The image recording apparatus according to the present invention is provided with: motion detection modules 122 as detection means which detects motion information indicating a momentary motion level, on the basis of the data size of each piece of frame data of compressed image data; and a storage device 13 as storage means which stores the compressed image data and the motion information in association with time information on the image data.

Description

  The present invention relates to a recording device for recording video data and a search / playback device for displaying video based on motion information of the video data.

  A recording device in a conventional monitoring system or the like first records images from a number of cameras for a long time. Then, search and reproduction are performed, and monitoring or the like is performed by confirming whether any abnormal state such as the occurrence of an incident has occurred. Therefore, the video search function is important, and it is particularly effective for searching for an abnormal state in a short time by searching based on the motion in the video taken by the camera. Here, the motion indicates a change in position or movement of a person or object in the video.

  The surveillance system disclosed in Patent Document 1 extracts an image with motion by performing image processing on an image captured by a surveillance video camera, adds time information, and records the information as image search information. ing.

JP 2004-282675 A

  Here, in the conventional monitoring system, the video recorded in the recording device is subjected to various video processes to search for a video with motion. In the case of using a network camera that distributes video data compressed by H.264, MPEG4, or the like, it is necessary to decompress the compressed video data in a recording device and perform various video processing before creating search data.

  Therefore, a huge amount of signal processing is required to create search data, and using a high-performance signal processing device capable of performing these signal processings for the monitoring system increases the overall cost. .

  The present invention has been made to solve the above-described problems, and it is an object of the present invention to provide a recording device and a search / playback device capable of recording, searching and playing back motion images without requiring enormous signal processing. To do.

  The recording apparatus according to the present invention detects motion information indicating a momentary motion level based on an acquisition means for acquiring compressed video data and a data size of each frame data of the compressed video data. It is characterized by comprising a detection means and a storage means for storing the compressed video data and the motion information in association with time information of the video data.

  The search / playback apparatus according to the present invention reads out the motion information from the storage means and displays the time of the video to be displayed based on the display by the first reading means and the display by the first reading means. It is characterized by comprising: a selecting means that can be selected further; and a second reading means that reads out the video data related to the selected time from the storage means, expands it and displays it on the display means.

  According to the recording apparatus of the present invention, the acquisition means for acquiring the compressed video data, and the motion information indicating the momentary motion level based on the data size of each frame data of the compressed video data. By providing detection means for detecting and storage means for storing the compressed video data and the motion information in association with the time information of the video data, the compressed video data is not decompressed, and the data is stored. Since motion information can be obtained from the size, video data expansion processing and video data video processing can be reduced, and a cost-effective recording apparatus can be provided.

  According to the search / playback apparatus of the present invention, the motion information is read from the storage means and displayed on the display means, and the time of the video to be displayed based on the display by the first readout means. And a second reading unit that reads out the video data related to the selected time from the storage unit, expands it, and displays it on the display unit. The time can be selected based on the motion information without the need for processing, and the corresponding video can be displayed.

It is a figure which shows the monitoring system structure concerning Embodiment 1 of this invention. It is a figure explaining the video recording operation concerning Embodiment 1 of this invention. It is a figure explaining the structure of the video data preserve | saved at the input buffer 121 concerning Embodiment 1 of this invention. It is a figure which shows the data size of each flame | frame of the video data concerning Embodiment 1 of this invention. It is a figure which shows the data size of P frame concerning Embodiment 1 of this invention. It is a figure which shows the data of the motion detection concerning Embodiment 1 of this invention. It is a figure explaining the search operation | movement and reproduction | regeneration operation | movement concerning Embodiment 1 of this invention. It is a figure explaining the reproduction | regeneration screen in the monitoring terminal concerning Embodiment 1 of this invention.

<A. Embodiment 1>
<A-1. Configuration>
FIG. 1 is a system configuration diagram showing a configuration of a monitoring system using a network recording apparatus according to the first embodiment of the present invention.

  The network 100 is a network such as the Internet or a LAN. For example, the network 100 includes four network cameras 20a, a network camera 20b, a network camera 20c, a network camera 20d, two monitoring terminals 30a, and a monitoring terminal. It is assumed that the terminal 30b and one network recording device 10 are connected. As for the number of units, the number of units necessary for the configuration of the monitoring system can be freely determined.

  The monitoring terminal 30a and the monitoring terminal 30b are obtained by operating application software for monitoring on a personal computer, and display live video from a network camera or search for video recorded on the network recording device 10. And a function for making necessary settings for the network recording device 10. A plurality of monitoring terminals can be installed in the same monitoring system and operated simultaneously.

  The network camera 20a, the network camera 20b, the network camera 20c, and the network camera 20d are configured to monitor the compressed video data via the network 100 in response to a request from the monitoring terminal 30a and the monitoring terminal 30b. Send to 30b. The monitoring terminal 30a and the monitoring terminal 30b expand and display the compressed video data.

  The network camera 20a, the network camera 20b, the network camera 20c, and the network camera 20d send compressed video data for recording to the network recording device 10 via the network 100 based on a request from the network recording device 10. . The network recording device 10 records the compressed video data.

  The video data sent from the network camera 20a, the network camera 20b, the network camera 20c, and the network camera 20d is, for example, H.264. It is compressed by the H.264 video compression method. As a result, the amount of communication can be reduced. For example, even when the Internet line is used and the bandwidth of the network 100 is not so large, the monitoring system functions normally.

  The network recording device 10 includes an I / F 11 (InterFace) for connection to the network 100, a controller 12 that performs various controls, and a storage device 13 that stores video data and search data.

  The controller 12 is composed of a microcomputer, and performs various controls by a built-in program. The storage device 13 is composed of a hard disk drive and can store video data and search data.

<A-2-1. Recording operation>
Next, the recording operation will be described. FIG. 2 is a functional configuration diagram for explaining a recording operation of the network recording apparatus according to the first embodiment of the present invention.

  For example, the four network cameras 20a, 20b, 20c, and 20d shown in FIG. Video data compressed by the H.264 system is sent.

  The controller 12 acquires the compressed video data via the I / F 11 as an acquisition unit, sorts the video data for each network camera in the input buffer 121 in the controller 12 and temporarily stores the video data. At this time, the video data is associated with the time information of the video data so that the acquisition time can be known. Here, the time information is, for example, information indicating the time when the video is captured, and is defined for each frame of the video.

  H. Temporarily stored in the input buffer 121. As shown in FIG. 3, the video data compressed by the H.264 system is composed of an I frame and a P frame.

  The I frame has a large data size because it has information for all of one screen. On the other hand, since the P frame is difference information from the previous screen, the data size is smaller than that of the I frame. Since the data size of the P frame is the difference information as described above, there is a feature that the data size is small if there is no motion (motion) and increases according to the motion if there is motion.

  The controller 12 extracts video data from each input buffer 121 in frame units in the order of the acquired time. Then, header information including camera identification information and time information is added to the video data, and the video data is temporarily stored in the video data construction buffer 125. Thereafter, recording is performed on the storage device 13 via the storage device control module 126.

<A-2-2. Search data generation operation>
On the other hand, on the search data construction buffer 123, search data for performing time search is constructed and stored in the storage device 13 in association with the video data.

  At this time, the motion detection module 122 analyzes each frame size of the video data in the input buffer 121 to generate search data, associates it with the time information of the video data on the search data construction buffer 123, and 13 is stored.

  Here, the search data generation operation will be described in detail. 4 shows the H.264 acquired from the network camera. 6 is a graph showing a change in frame size of H.264 compressed data.

  Since the GOV (Group of Video Object Plane) is 32, there is shown a state in which there are approximately 30 Kbytes of I frames at a rate of 1 frame per 32 frames.

  FIG. 5 is a graph showing changes in the data size of the P frame with the I frame removed. In the case shown in FIG. 5, there is no moving object in the video in 0 to 19 seconds, so the data size of the P frame is kept small. Between 20 and 25 seconds, for example, when a person passes in front of the camera, a motion is generated in the video, and the data size of the P frame is increased.

  Here, as a process of converting the data size of each frame shown in FIG. 4 to the data size of the P frame shown in FIG. 5, the header analysis of each frame is performed, and the process of extracting only the P frame is performed. However, other conversion processing may be used for extraction. For example, the data sizes of two adjacent frame data may be compared and the smaller one may be used for the motion detection process. Usually, the I frame is larger in size than the P frame, and the I frames are not adjacent to each other. Therefore, motion can be detected by such a simple processing method.

  Since these conversion processes are performed using only the data size as a criterion, The same processing can be performed using data of different formats such as H.264 and MPEG4.

  FIG. 6 is a graph in which the maximum value of the data size of the P frame per second is motion information (motion level). The unit time of the data size is not limited to 1 second. The motion information indicates the momentary motion level, and may be any information indicating a reference value based on the data size, such as the maximum value or the average value of the data size within a predetermined time.

  By associating this motion information with the time information of the video data, it can be seen at which time there is a motion, for example, in 20 to 25 seconds. Further, when combined with video data stored separately, it is possible to specify which video the motion is.

  The motion detection module 122 as detection means detects the motion information at each time in each network camera by the method as described above and writes it in the search data construction buffer 123 as search data. Further, the video data is associated with time information and stored in the storage device 13.

  In this way, H.C. Since the motion information is detected from the data size of the P frame of the H.264 compressed data and the search data is generated, the search data can be generated by a simple process. In addition, since the performance required for the controller 12 can be kept low, the cost of the network recording device 10 can be reduced.

<A-2-3. Search and playback operations>
FIG. 7 is a diagram for explaining search and playback operations according to the first embodiment of the present invention.

  When the monitoring terminal 30a (or the monitoring terminal 30b) requests the network recording device 10 for search data at the designated time, the controller 12 first reads the search data for the requested date from the storage device 13. The data is read into the search data read buffer 127 as a means, and the search data is transmitted to the monitoring terminal 30a.

  When receiving the search data at the designated time, the monitoring terminal 30a displays a graph of motion information (motion level) for each network camera on the screen for 24 hours, for example. Motion information (motion level) data is detected from the search data.

  If necessary, only a graph of motion information (motion level) of a specific network camera is displayed, or the graph display screen is enlarged, for example, a graph is displayed in a range of 1 hour from 10 to 11 o'clock. You can also.

  For example, a user who uses the monitoring terminal 30a determines a network camera to be played back and a time thereof with reference to a change in motion level of each network camera displayed on the screen, and requests execution of the playback. This operation is executed, for example, by placing the cursor on the motion level graph displayed on the screen and pressing the play button.

  Based on the requested network camera and time information, the monitoring terminal 30a identifies, for example, the ID of the video data associated with the search data, and requests the video recording device 10 for the video data of that ID.

  The controller 12 reads the video data of the specified ID from the storage device 13 into the video data read buffer 128 as the second reading means, and transmits it to the monitoring terminal 30a.

  The monitoring terminal 30a extracts the video data at the designated time of the requested network camera from the received video data, decompresses it, and reproduces the video.

  An example of the playback screen is shown in FIG. A playback video 300 is displayed at the center, and the playback time can be changed by the time change slider 301. With the current playback time as the center, the motion level of 5 minutes before and after (total 600 seconds) is displayed in the motion level window 302, and it is possible to know when and how much motion has occurred. In this way, the target video can be easily found.

  Further, when the time change slider 301 is operated, the playback video 300 at the specified time is displayed and the motion level data displayed in the motion level window 302 is also displayed in conjunction with the movement (from a wide range). It is easy to find video with motion.

  As described above, since the graph of the motion level is displayed on the screen and the playback time is selected, the target playback video can be easily searched. In addition, it is not limited to the aspect which displays an image | video and motion information (motion level) on the same screen.

  In the present embodiment, the video data compression method is H.264. H.264 is shown, but other compression methods may be used, for example, MPEG4.

<A-3. Effect>
According to the first embodiment of the present invention, in the recording apparatus, motion as detection means for detecting motion information indicating the momentary motion level based on the data size of each frame data of compressed video data. By providing the detection module 122 and the storage device 13 as storage means for storing the compressed video data and motion information in association with the time information of the video data, the compressed video data can be decompressed without decompression. Since motion information can be obtained from the data size, video data expansion processing and video data video processing can be reduced, and a cost-effective recording apparatus can be provided.

  Further, according to the first embodiment of the present invention, in the recording apparatus, the I / F 11 as the acquisition unit is H.264. By acquiring video data compressed in the H.264 format, Motion information can be obtained from the data size of the P frame of H.264 compressed data.

  Further, according to the first embodiment of the present invention, in the recording apparatus, the I / F 11 as the acquisition unit acquires the video data compressed by the MPEG4 method, so that the compressed video data corresponding to MPEG4 can be used. Motion information can be obtained.

  In the method according to the present invention, motion information is acquired based only on the data size. The same processing can be applied to data in different formats such as H.264 and MPEG4.

  Further, according to the first embodiment of the present invention, in the recording apparatus, the motion detection module 122 as the detection unit compares the data sizes of adjacent frame data, and based on the smaller data size, the motion information By detecting, motion can be detected with a simple processing method.

  Further, according to the first embodiment of the present invention, in the search / playback device, the search data reading buffer 127 as the first reading means for reading the motion information from the storage device 13 as the storage means and displaying it on the display means, Based on the display by the search data reading buffer 127, the selection means that can select the time of the video to be displayed from the outside, and the video data related to the selected time are read from the storage device 13, decompressed, and displayed on the display means. By providing the video data reading buffer 128 as the second reading means to be displayed, it is possible to reproduce the video at a desired time from the motion information without expanding the video data.

  Further, according to the first embodiment of the present invention, in the search / playback device, the display means displays the video data and the motion information at the same time, thereby selecting the playback time from the motion information displayed on the screen, The video at the time can be easily searched.

  10 network recording device, 11 I / F, 12 controller, 13 storage device, 20a to 20d network camera, 30a, 30b monitoring terminal, 100 network, 121 input buffer, 122 motion detection module, 123 search data construction buffer, 125 video Data construction buffer, 126 storage device control module, 127 retrieval data read buffer, 128 video data read buffer, 300 playback video, 301 time change slider, 302 motion level window.

Claims (6)

Acquisition means for acquiring compressed video data;
Detection means for detecting motion information indicating a momentary motion level based on the data size of each frame data of the compressed video data;
A storage means for storing the compressed video data and the motion information in association with time information of the video data,
Recording device. The acquisition means is H.264. Obtaining video data compressed in the H.264 format,
The recording device according to claim 1. The acquisition means acquires video data compressed by the MPEG4 system,
The recording device according to claim 1. The detection means compares the data size of each adjacent frame data and detects the motion information based on a smaller data size,
The recording device according to claim 1. First reading means for reading out the motion information from the storage means according to any one of claims 1 to 4 and displaying the motion information on a display means;
Selection means capable of selecting the time of video to be displayed from outside based on the display by the first reading means;
The video data relating to the selected time is read from the storage means, and is expanded and displayed on the display means.
Search and playback device. The display means displays the video data and the motion information at the same time,
The search reproduction apparatus according to claim 5.