JP2008278323A - Network camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a network camera which can record an image and sound before the occurrence of a change by sending information of sound change and image change prior to corresponding image and sound and eliminates the need of a buffer in a server when performing storage. <P>SOLUTION: An image encoding part 4 encodes an input image, a sound encoding part 5 encodes sound, a sound change recognition processing part 7 outputs sound change information when input sound changes more than a threshold, to notify a server for storing the encoded image and sound of storing timing, and an IP converting part 6 performs IP conversion of image and sound encoded data and sound change change information, and transmits the sound change information prior to the image and sound encoded data to the outside. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a network camera capable of delivering, for example, images (video) and audio.

  A conventional network camera encodes and outputs an input image and sound. For example, as in Patent Document 1, a subject is imaged and a video input unit that generates an analog video signal is input. A voice input unit for generating an analog audio signal, an A / D converter for digitizing the analog video signal and the analog audio signal and converting them into digital data, and compressing the digital data into compressed digital data An information compression unit, a packet generation unit for placing the compressed digital data on a payload of a packet conforming to a predetermined protocol, and the congestion state of a network using the predetermined protocol, the packetized compressed digital data, Various transmission systems including information on the bandwidth of the network and whether or not transmission is possible. A transmission control unit that performs various transmission controls with reference to information, a network interface unit that transmits a packet permitted to be transmitted by the transmission control unit, and a control unit that controls each unit. It was.

  Further, as an additional function, there is a function having an image motion detection function, and as in Patent Document 2, a video signal subjected to noise suppression (noise reduction) processing can be obtained by performing inter-field signal processing of the captured video signal. In the television camera according to the present invention, a motion detection (motion detection) circuit that determines whether the captured subject is moving or stationary, and a noise suppression processing circuit that is controlled in accordance with a detection signal from the detection circuit. I had it.

  Some conventional network cameras monitor the presence / absence of voice. When the voice data is received via the network as in Patent Document 3, the voice data is temporarily stored in the voice reception buffer unit. A buffer control unit that stores and decodes audio data output from the audio reception buffer unit by an audio processing unit and outputs audio after DA conversion, and performs input / output control of audio data to the audio reception buffer unit And reception buffer level determination means for determining that there is no data or no sound when the audio data in the audio reception buffer unit continues for a certain period of time and is below a predetermined peak value, and determines that there is sound when the peak value is exceeded. And the buffer control means discards the audio data determined to be no data or no sound, closes the remaining audio data, and outputs it to the audio processing means. It was.

  In the server, images and sounds from the network camera are stored and recorded. However, due to storage capacity, only images and sounds when an environmental change occurs can be stored instead of continuous recording for 24 hours. there were.

JP 2004-147262 A (paragraph 0010) JP 2002-77704 A (paragraph 0005) JP 2006-14150 (paragraph 0012)

  A conventional network camera is configured as described above, and in a system that uses changes by motion detection or voice emitted by a network camera as a trigger for accumulation, recording of images and sounds is started from the time when the change emitted by the camera is received. However, there is a problem that it is necessary to always store a certain amount of data in a buffer in the server because it is impossible to record before the change occurs.

  The present invention has been made to solve the above-described problems, and records the image and sound before the occurrence of the change by sending the information of the sound change and the image change before the corresponding image and sound. An object of the present invention is to obtain a network camera that does not require a buffer in the server when storing.

  A network camera according to the present invention stores an image encoding unit that encodes an input image, an audio encoding unit that encodes audio input together with the image, and a server that stores the encoded image and audio. In order to notify the timing, when the input voice changes by a predetermined threshold or more, a voice change recognition processing unit that outputs voice change information indicating the change, encoded data of the image, and encoded data of the voice, An IP conversion unit for performing IP conversion on audio change information and transmitting the audio change information converted before the encoded image and audio data to the outside before the encoded image and audio data; It is to be prepared.

  According to the present invention, by sending information on audio changes and image changes before the corresponding images and sounds, it is possible to record the images and sounds before the occurrence of the change. This produces the effect of eliminating the need for a buffer.

An embodiment of the present invention will be described below.
Embodiment 1 FIG.
FIG. 1 is a configuration diagram of a network camera system including a network camera 1 according to Embodiment 1 of the present invention.
In FIG. 1, the network camera system is such that, for example, the network camera 1 transmits an IP packet to the server 2 via the network 3. The network camera 1 includes an image encoding unit 4, a voice encoding unit 5, an IP conversion unit 6, and a voice change recognition processing unit 7. The server 2 includes a packet determination unit 8 and a storage unit 9. Prepare.

  Here, the image encoding unit 4 performs A / D conversion and encoding on the input image, and the audio encoding unit 5 performs A / D conversion and encoding on the input audio.

  The voice change recognition processing unit 7 provides voice change information indicating that the input voice has changed when the input voice changes by a predetermined threshold value or more in order to notify the storage timing in the server 2 for storing the encoded image and voice. The level of the input voice is monitored, and when the threshold level specified in advance is exceeded, it is determined that the environmental change has occurred due to the voice change, and the IP conversion unit 6 Tell the voice change occurrence. The voice input to the network camera 1 is transferred to the voice change recognition processing unit 7 simultaneously with the voice encoding unit 5.

  In addition to the above, the voice change IP packet creation condition in the voice change recognition processing unit 7 is specified when the input voice level falls below a predetermined threshold level, or falls within a specific range. It can be arbitrarily settable when the state within the range continues for a certain period of time.

  The IP conversion unit 6 performs IP conversion on the encoded image data, the encoded audio data, and the audio change information, and converts the audio change information converted before the encoded image and audio data, The data is transmitted to the outside prior to the encoded data of the image and sound, and the IP packet of the image, sound and sound change is created and distributed to the network 3.

  In the server 2, the packet determination unit 8 determines whether an IP packet distributed to the network 3 is received by the server 2 on the receiving side and should be stored. When the packet determining unit 8 recognizes the voice change information of the voice change IP packet, it starts to store the image and the voice, and when the arbitrarily set time has elapsed, the storage of the image and the voice ends.

  The accumulating unit 9 accumulates the packets that are determined to be accumulated by the packet determining unit 8, and in order to save the storage capacity, the accumulation of images and sounds is not always recorded, but there is an environmental change around the network camera 1 Limited to time. The data stored in the storage unit 9 can be arbitrarily read by the user.

  Since the network camera 1 can create a voice change IP packet in a shorter time than the encoding of an image due to a small amount of information, the distributed voice change IP packet is a server on the receiving side. 2 can be reached earlier than the image encoded IP packet at the time of detecting the change. Further, the voice change recognition processing unit 7 can be preferentially processed.

  The time required for audio encoding can be reduced in a short time compared to image encoding. However, in order to synchronize the image and audio on the receiving side, it is common to provide a delay in audio distribution. Therefore, it can be considered that the image-encoded IP packet and the audio-encoded IP packet reach the receiving server 2 at the same time.

Next, the operation will be described.
FIG. 2 is a diagram showing an example of the time required for speech change recognition and the time difference required for image coding in Embodiment 1 of the present invention.
Considering the delay time of the image and voice encoding inside the network camera 1, the arrival time of the IP packet of the image, voice and voice change to the server is shown in time series, for example, as shown in FIG. When the image and sound are input to the network camera 1 in the order of image A (audio A), image B (audio B), image C (audio C),. If the unit 7 recognizes the change, the IP packet of the audio change information triggered by the audio B can be distributed before the image A before the audio B is encoded and distributed in the network camera 1. The arrival order to the server 2 is the order of the IP packet of the voice change information and the image (voice) encoded packet A triggered by the voice B, and the temporal order in the network camera 1 is switched.
In FIG. 2, the delay of image encoding is one frame, but the amount of delay differs depending on the structure of the network camera 1. (If the delay time is about 300 ms, a time difference of 10 frames occurs).

  In the server 2 on the receiving side, the received IP packet is determined by the packet determining unit 8, and when the voice change IP packet arrives, it is determined that an environmental change has occurred in the vicinity of the network camera 1, and the received image code The storage unit 9 starts storing the encrypted IP packet and the voice encoded IP packet as image and voice data.

  As shown in FIG. 2, after receiving the voice change IP packet, encoded image A (voice A) encoded data before the voice change arrives at the server 2 on the receiving side. Since the storage of the image and the sound is started upon arrival of the voice change IP packet, the storage can be started from the image A (voice A) before the image B (voice B) in which the environmental change has occurred. Since the image and sound before the environment change can be accumulated only by the unit 9, it is not necessary to provide a buffer. The number of frames that can be acquired before the environmental change changes depending on the length of the delay time of image encoding in the network camera 1. The larger the delay, the more image frames that can be acquired.

  In the prior art, recording is started after the change in sound is detected. Therefore, in order to record the image and sound before the change is detected (image A and sound A in FIG. 2), data is temporarily stored in a buffer in the server 2 in advance. However, in the first embodiment, the server 2 side starts buffering the image and sound by using the IP packet detection of the sound change information distributed from the network camera 1 as a trigger. It is possible to store images and sounds before the occurrence of environmental changes.

Although the first embodiment has been described by delaying the sound and synchronizing with the image, it is also possible to encode the sound prior to the image without synchronizing and distribute it from the network camera 1.
In this case, since it is not necessary to perform a delay for synchronizing with the image in the audio encoding unit 5, the structure in the network camera 1 is simplified.

  As described above, according to the first embodiment, the network camera 1 includes the image encoding unit 4 that encodes the input image, the audio encoding unit 5 that encodes the audio input together with the image, and the encoding. A voice change recognition processing unit 7 for outputting voice change information indicating that the input voice has changed when the input voice has changed by a predetermined threshold value or more in order to notify the storage timing to the server for storing the generated image and voice; The encoded data, the encoded audio data, and the audio change information are IP-converted, and the audio change information converted before the encoded image and audio data is converted into the encoded image and audio By providing the IP conversion unit 6 that transmits to the outside prior to the data, it is possible to send the information on the sound change and the image change before the corresponding image and sound, and to record the image and sound before the occurrence of the change. Can, when performing accumulation, an effect that eliminates the need for buffer in the server.

  In addition, according to the first embodiment, there is an effect that the storage capacity is improved on the server 2 side.

Embodiment 2. FIG.
FIG. 3 is a configuration diagram of a network camera system including the network camera 1 according to the second embodiment of the present invention.
The network camera 1 according to the second embodiment is obtained by adding an image change recognition processing unit 10 to the configuration of the network camera 1 according to the first embodiment.
The input image is sent to the image change recognition processing unit 10 simultaneously with the image encoding unit 4.

  When the image change recognition processing unit 10 detects a change in the image, the image change recognition processing unit 10 recognizes that the environment change has occurred, and notifies the IP conversion unit 6 of the occurrence of the environment change. The IP conversion unit 6 generates an image change IP packet and distributes it to the network 3. Other than the image change recognition processing unit 10, the operation is performed in the same manner as in the first embodiment, and image and sound encoding and sound change recognition are performed.

  In the second embodiment, when a change in image and sound occurs in the vicinity of the network camera 1, both the sound change IP packet and the image change IP packet are distributed, but both the sound change and the image change occur. Only when it occurs, it is recorded in the storage unit 9 by the server, thereby preventing unnecessary recording and saving storage capacity.

  When both the audio change and the image change occur in the vicinity of the network camera 1, first, after the audio change IP packet arrives at the server 2, the recording of the image and audio is started, and then the image is set within the set time. Since the changed IP packet arrives, accumulation is continued without discarding the accumulated data in the accumulation unit 9.

  When both the image change and the sound change occur around the network camera 1 and the image IP packet is issued before the sound change IP packet, within the arbitrarily set time after receiving the image change IP packet In addition, if the voice change IP packet is received, the stored data is not discarded, and the storage in the storage unit 9 is continued.

  When only a voice change occurs around the network camera 1, a voice change IP packet is transmitted from the network camera 1, but the image change IP packet is not distributed. The packet determination unit 8 of the server 2 starts recording the image and audio after arrival of the audio change IP packet. If the image change IP packet does not arrive within an arbitrarily set time, Until the image and sound data recorded in the storage unit 9 are discarded, the subsequent storage is stopped.

  When only an image change occurs around the network camera 1, an image change IP packet is issued, but an audio change IP packet is not issued. In the server 2, recording of an image and a sound is started by receiving the image change IP packet. However, if the sound change IP packet does not arrive within an arbitrarily set time, the storage unit 9 until that time. Discards the image and sound data recorded in, and stops the subsequent accumulation.

Since accumulation is performed only when an environmental change is detected for both images and sounds, unnecessary data accumulation can be avoided.
Even when the image change IP packet is issued first, the storage is performed only when the environmental change is detected in both the image and the sound, so that unnecessary data storage can be avoided. Further, the image change IP packet can be stored in the storage unit 9 only by arrival.

  As described above, according to the second embodiment, when the input image changes by a predetermined threshold or more, the image change recognition processing unit 10 that outputs the image change information indicating the change is provided. By converting the image change information into IP and transmitting the image change information and the audio change information converted before the encoded image and audio data to the outside before the encoded image and audio data By sending audio change and image change information before the corresponding image and sound, it is possible to record the image and sound before the change occurs, and no buffer is required in the server when storing The effect of doing.

1 is a configuration diagram of a network camera system including a network camera according to a first embodiment of the present invention. It is a figure of an example which showed the time required for the audio | voice change recognition in Embodiment 1 of this invention, and the time difference required for image coding. It is a block diagram of the network camera system containing the network camera of Embodiment 2 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Network camera, 2 servers, 3 networks, 4 Image coding part, 5 Voice coding part, 6 IP conversion part, 7 Voice change recognition process part, 8 Packet judgment part, 9 Storage part, 10 Image change recognition process part

Claims (2)

An image encoding unit for encoding the input image;
An audio encoding unit for encoding audio input together with the image;
A voice change recognition processing unit that outputs voice change information indicating that the input voice has changed when the input voice changes by a predetermined threshold value or more in order to notify the storage timing of the encoded image and voice in the server. When,
The image-encoded data, the audio encoded data, and the audio change information are IP-converted, and the audio change information converted before the image and audio encoded data is converted to A network camera, comprising: an IP conversion unit that transmits to the outside prior to encoded image and audio data. An image change recognition processing unit that outputs image change information indicating a change when the input image changes by a predetermined threshold value or more;
The IP conversion unit performs IP conversion on the image change information and converts the image change information and sound change information converted before the image and sound encoded data into the image and sound encoded data. 2. The network camera according to claim 1, wherein the network camera is transmitted to the outside earlier.

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