JP2006147114A - Recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recorder which can utilize the existing analog type recorder, reduce cost and improve the performance of analog and digital mixed recording. <P>SOLUTION: In this recorder, a frame switcher 108 synchronizes a signal from an analog signal input interface 103 with a clock. An encoder 111 converts a signal from the frame switcher 108 into a digital signal. The converted digital signal and the digital signal from a digital signal input interface 107 are transferred to recording media 116 and 117 through a recording medium interface circuit 115 to be digitally recorded. An analog signal is processed by a circuit 120 for an indicator to be analogly displayed, and a digital signal is temporarily buffered by a decoding memory 119 when a decoder 118 decodes the digital signal and displayed later than a signal from an analog camera. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a recording apparatus capable of processing a signal input through an input interface, whether it is an analog signal or a digital signal, and recording it in a digital format.

  Conventionally, digitalization of image recording apparatuses has progressed also in the field of surveillance cameras, and conventionally, a signal from a camera such as a time lapse recorder is transmitted to a recording apparatus as an uncompressed analog signal, and is recorded on a recording medium as it is. Type recording devices have been used. On the other hand, in recent years, a full digital recording apparatus that transmits a signal from a camera to a recording apparatus as a digital signal and records the signal on a recording medium as it is has been developed and is becoming popular.

  As a recording device capable of both long-time recording and recording with priority on the amount of information when there is an abnormality, for example, a plurality of cameras that compress the captured video signal and output it as digital video data, and digital output from the plurality of cameras Transmission means for transmitting video data, display means for displaying the digital video data, detection means for detecting the presence or absence of an intruder or an intruder, and changing the picture configuration of the digital video data according to the detection result of the detection means There has been proposed a surveillance camera system including a variable compression unit capable of recording and a recording unit that records video data output from the variable compression unit on a recording medium (Patent Document 1).

When using such a digital recording device, install a camera with one or more digital outputs, construct a digital signal transmission network, and record these digital data in the recording device. Become. Since such digital recording is possible, the initial purpose can be achieved while maintaining the monitor image quality. However, the system configuration is complicated and the system cost is increased. Furthermore, in the case of a full digital recording apparatus, an analog signal from an analog camera cannot be directly input, so that an existing analog camera or the like cannot be directly connected to the recording apparatus.
JP 2002-262272 A (paragraphs [0011] to [0016], FIG. 1)

  Therefore, when an analog recording system already exists, it can be integrated by adding a digital recording system, and in addition to displaying analog signals on a display unit, digital input signals can be displayed simultaneously. There is a problem to be solved.

  An object of the present invention is to consider the above points and to add a digital recording system by utilizing an existing analog recording apparatus. At that time, it is possible to suppress cost increase and to perform analog / digital mixed recording. It is an object of the present invention to provide a recording apparatus capable of improving the performance.

  In order to achieve the above object, a recording apparatus according to the present invention includes one or more analog signal input interfaces capable of inputting an analog signal, one or more digital signal input interfaces capable of inputting a digital signal, and the analog signal input. One or more frame switchers that synchronize a signal from the interface with a reference clock, one or more encoders that convert the analog signal from the frame switcher into a digital signal, and the digital signal that is converted by the encoder Alternatively, a recording medium interface circuit for transferring the digital signal from the digital signal input interface to a recording medium, a digital recording medium connected to the recording medium interface circuit so as to be able to input / output, and the digital signal input interface One or more decoders for decoding the digital signal or the digital signal through the recording medium interface circuit into an analog signal, the analog signal from a previous frame switcher, and the analog signal converted from the digital signal by the decoder And a clock generation circuit for supplying the reference clock to the frame switcher, the encoder, the decoder and the display circuit in addition to the digital signal input interface to synchronize with each other. And.

  According to this recording apparatus, the analog signal input from the analog signal input interface is synchronized with the reference clock by the frame switcher, and then input to the encoder and converted into a digital signal. The digital signal converted by the encoder is recorded in a digital format on a recording medium through a recording medium interface circuit. The analog signal synchronized with the reference clock by the frame switcher is directly input to the display circuit and displayed on a display device such as a monitor. On the other hand, the digital signal input from the digital signal input interface is recorded in a digital format on the recording medium through the recording medium interface circuit. The digital signal input from the digital signal input interface or the digital signal reproduced from the recording medium through the recording medium interface circuit is converted into an analog signal through the decoder, input to the display circuit, and displayed on the display. The clock generation circuit supplies a reference clock to the encoder, decoder, and display circuit in addition to the frame switcher, and synchronizes with each other.

  The recording apparatus may further include a buffer memory that is connected to and can be input / output from / to the decoder and can temporarily buffer the digital signal transferred to the decoder. By providing the buffer memory, the signal from the digital signal input interface can be temporarily buffered by the buffer memory when the signal is decoded by the decoder. When a digital signal is transmitted via a LAN or the like and data overflow or underflow occurs due to jitter or the like, the digital signal input from the digital signal input interface is temporarily buffered in the buffer memory. By doing so, the monitor display screen is prevented from being stationary by displaying it later than the analog signal input from the analog signal input interface.

  This recording apparatus may further include a display memory that is connected to the display circuit so as to be able to input and output and can temporarily buffer an analog signal input to the display circuit. In digital signal processing, it is inevitable that the delay time associated with digital processing will occur, but by temporarily buffering the analog signal from the analog signal input interface in the display memory connected to the display circuit, By delaying the display timing of the signal, it is displayed in accordance with the display timing of the delayed digital signal from the digital signal input interface, so that both signals are displayed at the same time when simultaneously displayed on the display unit. It is possible to prevent a sense of incongruity that can be remembered due to a timing shift.

  In this recording apparatus, the internal or external recording medium connected to the recording medium interface circuit can record the analog signal from the analog signal input interface and the digital signal from the digital signal input interface individually or simultaneously. be able to. With this configuration, analog / digital duplex signals can be recorded individually or simultaneously, and a flexible recording apparatus can be obtained. When recording at the same time, it is preferable to record both signals in synchronization by attaching a time code or the like.

  In the recording apparatus capable of recording both types of signals individually or simultaneously, signals from one or more inputs recorded on the recording medium can be reproduced simultaneously. By simultaneously reproducing signals from one or more inputs recorded on a recording medium, a reproduction screen that is simultaneously displayed through a plurality of channels can be used according to the type and manner of the signal source.

  In the recording apparatus, an analog output camera can be connected to the analog signal input interface, and a digital output camera can be connected to the digital signal input interface directly or through a LAN. Each interface can be applied to a surveillance camera system using two types of signals, analog and digital, by connecting a camera corresponding to the type of signal to be handled. There are existing analog output camera monitoring systems. By using this existing system, it is possible to obtain a recording apparatus that allows connection of a digital output camera in a manner that requires as little change in configuration as possible. Can do.

  According to the recording apparatus of the present invention, the analog signal input from the analog signal input interface is converted into a digital signal by the encoder, and then recorded in a digital format on the recording medium through the recording medium interface circuit, from the digital signal input interface. The input digital signal is recorded in a digital format on a recording medium through a recording medium interface circuit. In addition, the analog signal synchronized with the reference clock by the frame switcher is directly input to the display circuit. If there is an existing analog display, it is displayed on the analog display, and from the digital signal input interface. An input digital signal or a digital signal reproduced from a recording medium through a recording medium interface circuit is converted into an analog form through a decoder, input to a display circuit, and displayed using the same display. Since the clock generation circuit supplies a reference clock to the encoder, decoder, and display circuit in addition to the frame switcher to synchronize with each other, there is no signal synchronization deviation. In this way, the existing analog input can be used without changing the power supply or facilities for installing the analog-digital converter, etc., and the recording device equipped with the existing analog display can be used, which reduces the cost. It is possible to suppress the rise and improve the performance of the analog / digital mixed recording. Further, when an input analog signal and digital signal are displayed in real time or when reproduction is performed, analog and digital image display timing can be performed simultaneously.

  Embodiments of a recording apparatus according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram of a recording apparatus showing a first embodiment of the present invention. In FIG. 1, uncompressed analog signals input from a plurality of analog output cameras 101 and 102 that output analog signals are input to a recording device 121 through an analog signal input interface 103. Although the clock generation circuit 114 will be described later, the analog output cameras 101 and 102 operate asynchronously with the recording device 121, respectively. Therefore, the input analog signal is input to the frame switchers 108, 109... 110, and 108 in the first embodiment, and the frame switcher 108 synchronizes the signals with the recording device 121. In the digital output cameras 104 and 105, the built-in encoder has been synchronized with the recording device 121, and time information can be added to the captured data.

  The captured uncompressed analog signal is input from the frame switcher 108 to the encoders 111, 112,... 113, and in the first embodiment, the encoder 111 is digitally compressed and the digital compressed signal is recorded on a recording medium such as an HDD. The data is input to a recording medium interface circuit (hereinafter referred to as a recording medium I / F circuit) 115. Signals output from the analog output cameras 101 and 102 and converted into digital compressed signals are recorded on recording media 116 and 117 such as HDDs by the recording media I / F circuit 115. The signal from the frame switcher 108 is also input to the display circuit 120 for display on a monitor or the like in real time.

  Next, the digital compressed signals output from the plurality of digital output cameras 104 and 105 are input to the recording device 121 through the digital signal input interface 107 via the LAN 106. The digital compressed signal input to the recording device 121 is input to the recording medium I / F circuit 115 and recorded on recording media 116 and 117 such as HDDs in the same manner as an analog signal. The digital signal input interface 107 has an interface function for synchronizing clocks with the digital output cameras 104 and 105.

  The signal input to the digital signal input interface 107 is also input to the decoder 118 via the recording medium I / F circuit 115 or directly in order to display it on a monitor or the like in real time. 120.

  For the signal from the digital output camera, there is a possibility that data overflow or underflow may occur due to jitter or the like via the LAN 106. When the data overflow or underflow occurs, the display screen of the monitor becomes stationary. Therefore, the data is buffered by using the decoding memory 119, and the data always delayed from the display of the analog output cameras 101 and 102 is displayed. This prevents the monitor display screen from being stationary.

  The signals recorded on the recording media 116 and 117 such as HDDs are read out via the recording medium I / F circuit 115, and the digital compressed signal is decompressed by the decoder 118 and converted into an uncompressed signal. This signal is output to an external monitor or the like through the display circuit 120. Further, since the digital output cameras 104 and 105 and the recording device 121 are synchronized, the signal digitally compressed by the digital output cameras 104 and 105 and the signal synchronized by the frame switcher 108 are converted into the encoder 111 of the recording device 121. The digitally compressed signals are synchronized with each other. Therefore, at the time of reproduction, it is possible to correctly synchronize even when the analog output cameras 101 and 102 and the digital output cameras 104 and 105 reproduce a plurality of channels.

  Next, the output of the clock generation circuit 114 is output from the frame switchers 108, 109... 110 of the recording device 121, the encoders 111, 112, 113, the decoder 118, the display circuit 102, and the digital output camera 104, via the LAN 106. These circuits operate according to the synchronization generated by the clock generation circuit 114 in the recording apparatus 121. However, the analog output cameras 101 and 102 operate asynchronously with the clock of the clock generation circuit 114. Therefore, the recording device 121 is provided with frame switchers 108, 109... 110 to synchronize the signals input from the analog output cameras 101 and 102 with the recording device 121.

  Next, in the first embodiment shown in FIG. 1, an example of a time delay when displaying an imaging screen on a monitor in real time is shown in FIG. 2, and a timing chart at that time is shown in FIG.

  As shown in FIG. 2, images of the subjects 203 to 206 captured by the analog output camera 201 and the digital output camera 202 are displayed on the monitor 208 through the recording device 207. For example, it is assumed that the monitor displays a quadrant screen, and an image from the analog output camera 201 is displayed on the upper left 209 of the monitor. It is assumed that an image from the digital output camera 202 is displayed on the lower left 210 of the monitor. The two cameras 201 and 202 are caused to image the objects 203 and 205 displaying the same times 204 and 206, and how the images of the analog output camera 201 and the digital output camera 202 are delayed. When a clock or the like is imaged in such a situation, the time displayed on the monitor 208 is 12:00:10 for the image of the analog output camera 201 and 12:00:08 for the image of the digital output camera 202. Is displayed. From this display result, the signal of the digital output camera 202 is displayed on the monitor 208 with a delay of 2 seconds from the signal of the analog output camera 201.

  FIG. 3 shows a timing chart of the analog output camera 201 and the digital output camera 202 when the time delay phenomenon shown in FIG. 2 occurs. First, the imaging timings 301 and 302 of the analog output camera 201 and the digital output camera 202 are simultaneous, and then the display timing of the analog output camera 201 is corresponded to the recording device 207 by the frame switcher 108 (corresponding to the recording device 121 in FIG. 1). Assuming that a delay of one field is made to synchronize with the clock (clock of the clock generation circuit 114), the timing displayed on the monitor 208 is a timing 305 that is delayed by one field from the imaging timing. On the other hand, it is assumed that a signal captured by the digital output camera 202 is encoded by the digital output camera 202 into the camera digital compression signal and the compression is performed at timing 303. The compressed signal is transmitted to the recording device 207 via the LAN, and decoded by the decoder 118 for monitor display. The decoded signal is delayed by 2 seconds by combining buffering (using the decoding memory 119) for preventing signal over / underflow due to LAN jitter and the like and the delay of the LAN. Then, the display timing 306 is reached. As a result, the image 210 of the digital output camera 202 is displayed on the monitor 208 at a timing 306 with a delay of 2 seconds from the display timing 305 of the analog output camera 201.

  FIG. 4 is a diagram showing an example of delaying a signal from an analog camera and performing display processing at the same timing as a signal from a digital camera as a second embodiment of the recording apparatus according to the present invention. That is, when the signals from the analog output cameras 401 and 402 and the signals from the digital output cameras 404 and 405 input to the recording device 422 are displayed on a monitor or the like in real time, the signals from the analog output cameras 401 and 402 are displayed. By performing buffering by the display memory 421, display processing is performed at the same timing as the digital output cameras 404 and 405. In the second embodiment, elements equivalent to those in the first embodiment are replaced with reference numerals in the 400s instead of the reference numerals in the 100s, and the repetitive description is omitted unless otherwise specified.

  In the second embodiment, signals from the analog output cameras 401 and 402 and signals from the digital output cameras 404 and 405 are input to the recording device 422, and these signals are displayed on a monitor or the like in real time. At this time, since the signals from the digital output cameras 404 and 405 are buffered using the decoding memory 419 in order to prevent data underflow or overflow, the display timing is delayed. Therefore, in the second embodiment, signals from the analog output cameras 401 and 402 are digitally output by buffering the signals from the analog output cameras 401 and 402 in the display memory 421 provided in the display system circuit or the like. The display timing of the signals of the cameras 404 and 405 on the monitor is matched.

  Next, in the second embodiment shown in FIG. 4, FIG. 5 shows an example of a time delay when the imaging screen is displayed on the monitor in real time, and FIG. 6 shows a timing chart thereof. In the second embodiment, as in the first embodiment, as shown in FIG. 5, the images of the subjects 503 to 506 taken by the analog output camera 501 and the digital output camera 502 are recorded in the recording device 507 (FIG. 4). Then, it is displayed on the monitor 508 through the recording device 422). It is assumed that an image from the analog output camera 501 is displayed on the upper left 509 of the monitor. It is assumed that an image from the digital output camera 502 is displayed on the lower left 510 of the monitor. As in FIG. 5, when an object 504, 506 such as a watch is imaged, in this embodiment, the signal from the analog output camera 501 is displayed on the monitor by buffering the display memory 421 (FIG. 1). At the respective times, the image of the analog output camera 501 is displayed as 12:00:08, the image of the digital output camera 502 is also displayed as 12:00:08. In the second embodiment, the signal of the analog output camera 501 is also delayed and displayed on the monitor or the like in accordance with the signal delay of the digital output camera 502 as described above.

  A timing chart of the analog output camera 501 and the digital output camera 502 at this time is shown in FIG. As in FIG. 4, first, the imaging timings 601 and 602 of the analog output camera 501 and the digital output camera 502 are the same. In order to synchronize with the clock at 414), the display memory 421 is used for buffering in order to synchronize with the display timing of the digital output camera 502. Therefore, the monitor display becomes the display timing 605. On the other hand, the signal 602 picked up by the digital output camera 502 is encoded into a digital compression signal in the digital output camera 502 as in the first embodiment, and the compression is performed at timing 603. The compressed signal is transmitted to the recording device 422 via the LAN 406 and is decoded (by the decoder 418, the timing is 604) for monitor display, but the decoded signal is the jitter of the LAN 406, etc. By combining the buffering for preventing signal over / underflow (using the decoding memory 419) and the delay of the LAN 406, if the decoding timing is delayed by 2 seconds, the display timing 606 is obtained. As a result, the display timing 606 is displayed on the monitor at the same display timing 605 as the display of the analog output camera 501.

  By processing as described above, the display timings 605 and 606 when the signal from the analog output camera 501 and the signal from the digital output camera 502 are displayed on the monitor can be matched, and the images captured by the camera at the same timing are the same timing. Can be displayed. In each of the above embodiments, each interface and decoder has been described as one, but it is apparent that a plurality of interfaces and decoders may be provided. It is also clear that the display may be arranged with a plurality of display panels, or a single large screen display may be divided into a plurality of small screens and assigned to each. Further, with respect to the reproduction, it is possible to perform one of the follow-up reproductions with a variable speed, or reproduction with a certain time (including immediately after).

1 is a block diagram showing a configuration of a first embodiment of a recording apparatus according to the present invention. The figure which showed the delay state at the time of the monitor display of the analog output camera and digital output camera in this invention. The figure which showed the display timing chart to the monitor of the analog output camera and digital output camera in this invention. The block diagram which shows the structure of 2nd Embodiment of the recording device by this invention. The figure which showed the delay state at the time of the monitor display of the analog output camera and digital output camera in this invention. The figure which showed the display timing chart to the monitor of the analog output camera and digital output camera in this invention.

Explanation of symbols

101, 102 Analog output camera 103 Analog signal input interface 104, 105 Digital output camera 106 LAN
107 Digital signal input interface 108, 109, 110 Frame switcher 111, 112, 113 Encoder 114 Clock generation circuit 115 Recording medium interface circuit (recording medium I / F circuit)
116, 117 Recording medium 118 Decoder 119 Decoding memory 120 Display circuit 121 Recording device 201 Analog output camera 202 Digital output camera 203, 204, 205, 206 Subject 207 Recording device 208 Monitor 209 Analog output camera monitor display screen 210 Digital output Camera monitor display screen 301 Analog output camera imaging timing 302 Digital output camera imaging timing 303 Digital output camera encoding timing 304 Digital output camera decoding timing 305 Analog output camera display timing 306 Digital output camera display timing 401, 402 Analog output camera 403 Analog signal Input interface 404, 405 Digital output camera 406 LAN
407 Digital signal input interface 408, 409, 410 Frame switcher 411, 412, 413 Encoder 414 Clock generation circuit 415 Recording medium interface circuit (recording medium I / F circuit)
416, 417 Recording medium 418 Decoder 419 Decoding memory 420 Display circuit 420 Display memory 421 Recording device 501 Analog output camera 502 Digital output camera 503, 504, 505, 506 Subject 507 Recording device 508 Monitor 509 Analog output camera monitor display Screen 510 Digital output camera monitor display screen 601 Analog output camera imaging timing 602 Digital output camera imaging timing 603 Digital output camera encoding timing 604 Digital output camera decoding timing 605 Analog output camera display timing 606 Digital output camera display timing

Claims (6)

One or more analog signal input interfaces capable of inputting analog signals;
One or more digital signal input interfaces capable of inputting digital signals;
One or more frame switchers that synchronize a signal from the analog signal input interface with a reference clock;
One or more encoders for converting the analog signal from the frame switcher into a digital signal;
A recording medium interface circuit for transferring the digital signal converted by the encoder or the digital signal from the digital signal input interface to a recording medium;
A digital recording medium connected to the recording medium interface circuit in an input / output manner;
One or more decoders for decoding the digital signal from the digital signal input interface or the digital signal through the recording medium interface circuit into an analog signal;
A display circuit for displaying the analog signal from the frame switcher and the analog signal converted from the digital signal by the decoder on a display;
A recording apparatus comprising: in addition to the digital signal input interface, a clock generation circuit that supplies the reference clock to the frame switcher, the encoder, the decoder, and the display circuit to synchronize with each other.   2. The recording according to claim 1, further comprising a buffer memory connected to the decoder so as to be able to input and output, and capable of temporarily buffering the digital signal transferred to the decoder. apparatus.   2. A display memory which is connected to the display circuit so as to be able to input and output and is capable of temporarily buffering the analog signal input to the display circuit. The recording device described in 1.   4. The analog signal from the analog signal input interface and the digital signal from the digital signal input interface can be recorded individually or simultaneously on the recording medium. Recording device.   The recording apparatus according to claim 4, wherein signals from one or more inputs recorded on the recording medium can be reproduced simultaneously.   6. An analog output camera can be connected to the analog signal input interface, and a digital output camera can be connected to the digital signal input interface directly or through a LAN. The recording device described.

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