Network Camera

Abstract

We provide a network camera that can implement compensation measures for video interruptions. [Solution] The network camera 10 includes an imaging unit 14 that generates frame images at regular time intervals, a main processing unit 11 that performs video recording processing on video data captured by the imaging unit 14, an auxiliary processing unit 15 that operates independently of the main processing unit 11 and performs still image recording processing to record frame images received from the imaging unit 14 as still image data at predetermined time intervals, and a non-volatile storage unit 16 that records still image data through the still image recording processing of the auxiliary processing unit.

Description

Technical Field

[0001] The present disclosure relates to a network camera.

Background Art

[0002] Network cameras are often used for applications such as security and surveillance, and are often used to continuously operate and record video. In addition, network cameras are designed to receive user commands via a network and execute the instructed processing, and have software for that purpose. Patent Document 1 discloses a surveillance camera device that can record only necessary parts in high quality while continuously operating by combining a video camera and a high-quality still camera.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

Means for Solving the Problems

[0006] To solve the above problems, the network camera of this disclosure is characterized by comprising: an imaging unit that generates frame images at regular time intervals; a main processing unit that performs video recording processing of video data captured by the imaging unit; an auxiliary processing unit that operates independently of the main processing unit and performs still image recording processing to record frame images received from the imaging unit as still image data at predetermined time intervals; and a recording unit that records still image data through the still image recording processing of the auxiliary processing unit.

[0007] Furthermore, the network camera may be configured to include a power supply unit that supplies power to the entire network camera, and a power storage unit that stores power while the power supply unit is operating and supplies power to the imaging unit, the auxiliary calculation unit, and the recording unit when the power supply unit is stopped.

[0008] Furthermore, in the still image recording process of the auxiliary calculation unit, the network camera can be configured such that still image data is recorded in accordance with a count value that has an upper limit, the count value is updated so that it increases by one with each recording of still image data, and the count value is reset to its initial value when it reaches the upper limit.

[0009] Furthermore, in the above-mentioned network camera, the auxiliary calculation unit can be configured to operate at normal power consumption during the period when still image recording processing is being performed, and to enter a low-power standby mode when still image recording processing is not being performed. [Effects of the Invention]

[0010] The network camera disclosed herein has the effect of being able to compensate for interruptions in video by performing still image recording processing by the auxiliary processing unit, even when the main processing unit is unable to perform video recording processing. [Brief explanation of the drawing]

[0011] [Figure 1] This diagram shows the configuration of a network camera according to one embodiment of the present disclosure. [Figure 2]This flowchart shows an example of the processing flow for still image recording by the auxiliary calculation unit. [Figure 3] This diagram illustrates the process of interpolating video data in an NVR (Network Video Recorder). [Figure 4] This flowchart shows another example of the processing flow for still image recording by the auxiliary calculation unit. [Modes for carrying out the invention]

[0012] [First Embodiment] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. Figure 1 is a block diagram showing the configuration of a network camera 10 according to one embodiment of the present disclosure. As shown in Figure 1, the network camera 10 includes a main processing unit 11, a communication unit 12, a PoE (Power over Ethernet) power receiving unit (power supply unit) 13, an imaging unit 14, an auxiliary processing unit 15, a non-volatile storage unit (recording unit) 16, and a power storage unit 17. The network camera 10 is capable of communicating with external devices connected via a network (Ethernet in this embodiment). These external devices include a main PC (personal computer) 20 for operating the network camera 10 and an NVR (network video recorder) 21 for recording video data.

[0013] The main processing unit 11 runs the OS of the network camera 10 and manages the entire network camera system. For example, the main processing unit 11 encodes the video data captured by the imaging unit 14 in h.246 or h.265, and runs an HTTP server to receive operations from the user (operations from the main PC 20).

[0014] The communication unit 12 communicates with external devices via Ethernet. For example, the communication unit 12 sends video data encoded by the main processing unit 11 to the NVR 21 for recording, or receives operation requests from the main PC 20.

[0015] The PoE power receiving unit 13 receives the power transmitted via Ethernet and supplies power to the entire network camera 10.

[0016] The imaging unit 14 generates frame images at regular time intervals. When the PoE power receiving unit 13 is supplying power, the imaging unit 14 operates by receiving power from the PoE power receiving unit 13. When the PoE power receiving unit 13 is not supplying power, the imaging unit 14 operates by receiving power from the power storage unit 17.

[0017] The auxiliary arithmetic unit 15 operates independently of the main arithmetic unit 11. At a predetermined time interval (for example, every 1 second), it encodes the frame images received from the imaging unit 14 in JPEG or the like and stores them as still images in the non-volatile memory unit 16. The still images at this time are stored together with information indicating the stored date and time. When the PoE power receiving unit 13 is supplying power, the auxiliary arithmetic unit 15 operates by receiving power from the PoE power receiving unit 13. When the PoE power receiving unit 13 is not supplying power, the auxiliary arithmetic unit 1 operates by receiving power from the power storage unit 17.

[0018] The non-volatile memory unit 16 can be connected to both the main arithmetic unit 11 and the auxiliary arithmetic unit 15. The still images stored from the auxiliary arithmetic unit 15 can be viewed or retrieved through the main arithmetic unit 11. When the PoE power receiving unit 13 is supplying power, the non-volatile memory unit 16 operates by receiving power from the PoE power receiving unit 13. When the PoE power receiving unit 13 is not supplying power, the non-volatile memory unit 16 operates by receiving power from the power storage unit 17. Also, various programs for operating the main arithmetic unit 11 and the auxiliary arithmetic unit 15 are stored in the non-volatile memory unit 16.

[0019] The power storage unit 17 includes, for example, a capacitor. During the period when the PoE power receiving unit 13 is supplying power (when the PoE power receiving unit 13 is operating), it accumulates power. When the PoE power receiving unit 13 stops supplying power (when the PoE power receiving unit 13 is stopped), it supplies power to the imaging unit 14, the auxiliary arithmetic unit 15, and the non-volatile memory unit 16.

[0020] The main arithmetic unit 11 and the auxiliary arithmetic unit 15 realize various functions by reading and executing various programs stored in the non-volatile memory unit 16 (e.g., storage or ROM). The main arithmetic unit 11 and the auxiliary arithmetic unit 15 may be realized by one or more control devices / arithmetic devices (CPU (Central Processing Unit), SoC (System on a Chip)). Also, the main arithmetic unit 11 and the auxiliary arithmetic unit 15 may be composed of one or more control circuits.

[0021] During the normal operation of the network camera 10, the frame images generated by the imaging unit 14 are generated at a high frame rate. That is, the imaging unit 14 captures video data that is video, and this video data undergoes video recording processing by the main arithmetic unit 11. Specifically, the main arithmetic unit 11 transmits the video data to the NVR 21 via the communication unit 12 and causes the NVR 21 to record the video data. Here, the normal operation refers to an operating state in which the PoE power receiving unit 13 supplies power to the entire network camera 10 and the main arithmetic unit 11 normally manages the entire system according to the OS.

[0022] In the network camera 10, due to software defects or the like, the OS may enter a stopped state, and the video may be interrupted even when the imaging unit 14 can be activated. Also, when the network camera 10 is restarted to recover from software defects, the video is interrupted even during the restart. The network camera 10 performs still image recording processing by the auxiliary arithmetic unit 15 in case the recording of video data by the imaging unit 14 is interrupted.

[0023] Figure 2 is a flowchart showing an example of the processing flow for still image recording by the auxiliary calculation unit 15. This processing flow is executed at predetermined time intervals (for example, every second). In this embodiment, the still image recording process is performed even during the normal operation of the network camera 10, regardless of whether or not video data recording has been interrupted. Furthermore, if the PoE power receiving unit 13 is not supplying power, the power storage unit 17 supplies power to the imaging unit 14, the auxiliary calculation unit 15, and the non-volatile storage unit 16 to perform the still image recording process.

[0024] In step S1 of this processing flow, it is first determined whether the non-volatile storage unit 16 is enabled or not. If the non-volatile storage unit 16 is enabled (YES in S1), the process proceeds to step S2. If it is not enabled (NO in S1), still image recording to the non-volatile storage unit 16 cannot be performed, and the process ends.

[0025] In step S2, it is determined whether there is sufficient free space in the non-volatile memory unit 16 (i.e., whether it is possible to record one frame of still images). If there is sufficient free space (YES in S2), the process proceeds to step S4. If there is not enough free space (NO in S2), old still image files (still image data) are deleted to free up space (S3) before proceeding to step S4.

[0026] In step S4, it is determined whether a date and time folder corresponding to the current time exists in the non-volatile storage unit 16. In this embodiment, still image files are saved in a predetermined date and time folder. Therefore, if a date and time folder corresponding to the current time exists (YES in S4), the process proceeds to step S6; if the date and time folder does not exist (NO in S4), a new date and time folder is created (S5) before proceeding to step S6.

[0027] In step S6, the frame image received from the imaging unit 14 is encoded in JPEG or the like. The encoded frame image is saved as still image data in the date and time folder of the non-volatile storage unit 16 (S7).

[0028] As described above, the network camera 10 can save (record) still images at regular intervals even when video data cannot be recorded due to software malfunctions or system restarts (when the main processing unit 11 cannot perform video recording processing). In other words, the network camera 10 can take compensatory measures against interruptions in video. Still image recording processing is managed by an auxiliary processing unit 15 that operates independently of the main processing unit 11. The auxiliary processing unit 15 can be a single-function, low-power auxiliary circuit that only performs the task of saving still images to the non-volatile memory unit 16 at regular intervals.

[0029] Furthermore, since each component necessary for recording still images—namely the imaging unit 14, the auxiliary calculation unit 15, and the non-volatile storage unit 16—can operate using power supplied from the energy storage unit 17, still images can be recorded even when the PoE power receiving unit 13 is unable to supply power, such as during a system restart (as long as there is power remaining in the energy storage unit 17).

[0030] If there is a period during which the network camera 10 is unable to capture video data, the NVR 21, which stores the video data, will also experience gaps in the recorded video data. If gaps are detected in the video data recorded by the NVR 21, the NVR 21 can acquire still images from the network camera 10 for the time period corresponding to the gaps and use the acquired still images to fill in the gaps.

[0031] Figure 3 illustrates the video data interpolation process in NVR21. As shown in Figure 3, internally, video data is stored in files, for example, in one-minute increments. Figure 3 illustrates video data from 14:41 to 14:46, and in Figure 3(A), the video data is interrupted between 14:43 and 14:44. In this case, NVR21 can acquire still image data from the network camera 10 for the period from 14:43 to 14:44, convert the acquired still image data into video data, and insert it into the video data as interpolation data for storage (see Figure 3(B)).

[0032] [Second Embodiment] Figure 4 is a flowchart showing another example of the processing flow for still image recording by the auxiliary calculation unit 15. This processing flow is executed at predetermined time intervals (for example, every second). In this embodiment, the still image recording process is performed even during the normal operation of the network camera 10, regardless of whether or not video data recording has been interrupted.

[0033] In step S11 of this processing flow, the count value is updated. For example, if the count value is n (n=1,2,...Nmax), it is updated from n to n+1 (the count value increases by 1). If the updated count value is less than or equal to the upper limit (i.e., Nmax) (YES in S12), the process proceeds to step S14. If the count value exceeds the maximum value (NO in S12), the count value is initialized (i.e., returned to 1) (S13) before proceeding to step S14.

[0034] In step S14, the frame image received from the imaging unit 14 is encoded in JPEG or the like. The encoded frame image is saved in the non-volatile storage unit 16 with a file name corresponding to the count value (S15).

[0035] In the flow of this embodiment, the number of still image frames stored in the non-volatile storage unit 16 is limited to the upper limit of the count value, and still images can be recorded while rotating the count value. That is, once the number of still images to be stored reaches the upper limit, the oldest still images are overwritten in order. As a result, the data of the stored still images does not exceed the capacity of the recording area of ​​the non-volatile storage unit 16, eliminating the need for a free space check as in the flow of Figure 2, and shortening the processing time. As a result, the power required for still image recording can be reduced. Note that at the start of the flow in Figure 4, the file corresponding to the count value n at that time is the newest still image, and the file corresponding to the count value (n+1) is the oldest still image.

[0036] [Third Embodiment] As described above, the processing flow for still image recording by the auxiliary calculation unit 15 is performed at predetermined time intervals. It is preferable that the auxiliary calculation unit 15 operates at normal power consumption only during the period in which still image recording processing is performed, and remains in standby mode with low power consumption when recording processing is not being performed. This makes it possible to extend the operating time when the external power supply is interrupted and the unit operates by receiving power from the power storage unit 17.

[0037] [Fourth Embodiment] In each of the above embodiments, still image recording by the auxiliary calculation unit 15 is always performed regardless of whether or not video (moving image) recording by the main calculation unit 11 is performed. However, still image recording by the auxiliary calculation unit 15 may be performed only when video recording is not performed, and not when video recording is performed by the main calculation unit 11.

[0038] In this case, the auxiliary calculation unit 15 monitors the operation of the main calculation unit 11, and if the operation of the main calculation unit 11 can no longer be detected, the auxiliary calculation unit 15 should perform still image recording.

[0039] The embodiments disclosed herein are illustrative in all respects and are not intended to be restrictive. Therefore, the technical scope of this disclosure is not to be interpreted solely by the embodiments described above, but rather by the claims. [Explanation of Symbols]

[0040] 10 Network Cameras 11 Main calculation section 12 Communications Department 13. PoE Power Receiving Unit (Power Supply Unit) 14 Imaging Unit 15 Auxiliary calculation section 16. Non-volatile memory unit (recording unit) 17. Energy Storage Unit 20 Main PC 21 NVR

Claims

1. An imaging unit that generates frame images at regular time intervals, The main processing unit performs video recording processing on the video data captured by the imaging unit, An auxiliary calculation unit operates independently of the main calculation unit and performs still image recording processing to record frame images received from the imaging unit as still image data at predetermined time intervals. A network camera characterized by comprising a recording unit that records still image data through still image recording processing by the auxiliary calculation unit.

2. A network camera according to claim 1, A power supply unit that supplies power to the entire network camera, A network camera characterized by having a power storage unit that stores power while the power supply unit is in operation, and supplies power to the imaging unit, the auxiliary calculation unit, and the recording unit when the power supply unit is stopped.

3. A network camera according to claim 1, In the still image recording process of the auxiliary calculation unit, still image data is recorded in accordance with a count value that has an upper limit. The aforementioned count value is updated to increase by one with each recording of a still image, and the count value is reset to its initial value when it reaches an upper limit, characterized in that the network camera is configured to do so.

4. A network camera according to claim 1, The aforementioned auxiliary calculation unit operates at normal power consumption during the period when still image recording processing is performed, and enters a low-power standby mode when still image recording processing is not being performed, characterized in that it is a network camera.

Images