JP5750590B2 - Imaging device, intercom device, intercom system - Google Patents

Description

  The present invention relates to an imaging device, an interphone device including the imaging device, and an interphone system including the interphone device.

  2. Description of the Related Art As conventional imaging devices, there are devices mounted on intercom devices of interphone systems (mainly door phone slaves and lobby intercoms used by visitors). For example, the conventional device described in Patent Document 1 detects a position to be magnified such as a visitor's face from an image captured by a camera of a door phone slave unit, and then detects it by a position detection unit. The position of the enlarged display is changed following the movement of the visitor.

JP-A-6-38214

  By the way, in recent imaging apparatuses, with the advance of image processing technology, a face area is recognized from a person's subject image and an enlargement process is automatically performed so that the recognized face area is positioned at the approximate center of the angle of view. It has been broken. However, both the process of tracking a visitor (tracking process) and the process of detecting the visitor's position (face area) (face detection process) as in the conventional example described in Patent Document 1 are executed. In this case, there is a possibility that the image processing load in the imaging apparatus is significantly increased, and it is difficult to track visitors. If the hardware that executes image processing (CPU, image processing IC, etc.) is high-performance, it can handle the increased burden of image processing, but such high-performance hardware is used. If it does, there exists a problem that the manufacturing cost of an imaging device will rise.

  The present invention has been made in view of the above problems, and an object thereof is to reliably track and image a human face while suppressing an increase in manufacturing cost.

  An image pickup apparatus according to the present invention includes an image pickup means for picking up an image, a storage means for storing the image, a face detection means for detecting a human face existing area in the image, and an enlargement of a partial area of the image. And an adjustment unit that adjusts an imaging range of the imaging unit or an enlargement area of the enlargement unit so that the person does not deviate from the image, and stores the memory during the detection process of the face detection unit. An adjustment process of the adjustment unit is performed on the image stored in the unit.

  In this imaging apparatus, it is preferable that the storage unit stores images at a constant cycle.

  In this imaging apparatus, the storage means stores an image with a first period longer than the frame period of the imaging means when there is a high possibility that a person is within the imaging range of the imaging means, and otherwise, the storage means It is preferable to store the image in a second period shorter than the first period and not longer than the frame period.

  The imaging apparatus preferably includes image generation means for generating an image in which a plurality of types of images including images adjusted by the adjustment means are distributed to a main screen and a sub screen.

  The imaging apparatus includes an output unit that selects and outputs an image adjusted by the adjustment unit and an image that is not adjusted by the adjustment unit, and whether the adjustment unit is selected by the output unit. Regardless, it is preferable to adjust the image.

  The intercom apparatus according to the present invention includes any one of the imaging apparatuses and a transmission unit that transmits an image captured by the imaging apparatus.

  The intercom system according to the present invention includes the intercom apparatus and an intercom apparatus including display means for displaying an image transmitted from the intercom apparatus.

  The imaging apparatus, intercom apparatus, and intercom system of the present invention have an effect that it is possible to reliably track and image a person's face while suppressing an increase in manufacturing cost.

It is a block diagram showing an embodiment of an imaging device, an intercom device, and an intercom system according to the present invention. It is a top view of the intercom child machine in the same as the above. It is a time chart for operation | movement description same as the above.

  Interphone cordless handset with camera (installed in lobby if lobby is installed) S installed in the exterior entrance of housing unit or common entrance (lobby) of apartment housing with built-in imaging device The present invention is applied to an interphone system including an interphone master unit (hereinafter abbreviated as “master unit”) M that performs a call with an interphone slave unit (hereinafter abbreviated as “slave unit”) S. Embodiments will be described in detail with reference to the drawings. However, the imaging device may be configured separately from the slave unit S.

  As shown in FIG. 1, a master unit M and a slave unit S corresponding to an interphone device are connected by a signal line Ls. In the intercom system according to the present embodiment, a voice signal is transmitted between the slave unit S and the master unit M via the signal line Ls to make a call, and an image (moving image) captured by the imaging device of the slave unit S is used. Image) is transmitted to the base unit M via the signal line Ls and displayed on the display unit 101 of the base unit M. Although not shown, the master unit M and the slave unit S transmit the sound collected by the microphone, the speaker, and the microphone via the signal line Ls (or a communication line (not shown)) and the other party. Calling means is provided for sounding the sound transmitted from the side from the speaker. However, since such communication means is well known in the art, illustration and description thereof are omitted.

  Base unit M includes display unit 101, signal transmission unit 100, operation input unit 103, base unit control unit 102, and the like. The display unit 101 includes a display device such as an LCD panel and a driver circuit that drives the display device to display a moving image (video). The signal transmission unit 100 transmits an audio signal, a video signal, and a control signal to the slave unit S via the signal line Ls (digital transmission or frequency division multiplex transmission), and a video transmitted from the slave unit S. Signal demodulation and decoding are performed. The operation input unit 103 receives an operation input such as a response button described later, and outputs an operation signal corresponding to the operation input to the parent device control unit 100. The parent device control unit 102 includes hardware such as a microcomputer and a memory and software, and controls the entire parent device M.

  The subunit | mobile_unit S is provided with the imaging part 1, the buffer memory 2, the image process part 3, the signal transmission part 4, the face detection process part 5, the view angle adjustment part 6, the operation input part 7, the control part 8, etc. The signal transmission unit 4 transmits an audio signal, a video signal, and a control signal to and from the signal transmission unit 101 of the parent device M via the signal line Ls. The imaging unit 1 serving as an imaging unit includes an imaging element 10 formed of a CCD image sensor or a CMOS image sensor, a lens 11 that collects light on an imaging surface of the imaging element 10, and the like. Note that the image sensor 10 can output a digital video signal (video signal) composed of a luminance component of Y and color difference components of U and V.

  The buffer memory 2 stores (buffers) a video signal (image data) output from the imaging unit 1 in accordance with an instruction from the control unit 8, and is an electrically rewritable nonvolatile semiconductor such as a flash memory. Consists of memory. However, the timing at which the buffer memory 2 stores (buffers) image data is determined by an instruction from the control unit 8.

  The image processing unit 3 performs an enlargement process (so-called digital zoom), a tracking process, an adjustment process, and the like in addition to a modulation process that digitally modulates a video signal read from the buffer memory 2 (for example, BPSK or QPSK). The enlargement process is an image for enlarging and displaying an arbitrary area (hereinafter referred to as “enlarged area”) smaller than one screen (one frame) from the original video signal. This is a process for creating a signal. The tracking process is a process for detecting the position on the image of the moving object (visitor) extracted by the interframe difference. However, since specific processing contents of this type of enlargement processing (digital zoom) and tracking processing are well known in the art, detailed description thereof will be omitted. Further, the adjustment process is a process of adjusting the imaging range of the imaging unit 1 or the enlargement area in the enlargement process so that a face existing area described later does not deviate from the image (view angle). Note that adjustment of the imaging range of the imaging unit 1 is realized by angle of view adjustment by the angle of view adjustment unit 6 as described later.

  The face detection processing unit 5 performs processing (face detection processing) for detecting a human face existing region (face existing region) in the captured image of the imaging unit 1. The face detection process is, for example, extracting a human face feature (such as eyes, nose, mouth) from an image captured in advance by the image capturing unit 1 to create a template, and creating an actual captured image. In contrast, this is a process of scanning a template and determining an area having a high matching (correlation) with the template as a face existing area. Note that the position information (position coordinates on the image) of the face existing area detected by the face detection processing unit 5 is transmitted to the image processing unit 3.

  The angle-of-view adjustment unit 6 adjusts the direction of the optical axis of the lens 11, that is, the angle of view of the imaging unit 1 by performing panning that rotates the imaging unit 1 in the horizontal direction and tilting that rotates the imaging unit 1 in the vertical direction. To do. Note that panning and tilting are realized by driving each rotation mechanism with a motor. The angle of view adjustment by the angle of view adjustment unit 6 is performed according to an instruction from the control unit 8 as described later.

  The signal transmission unit 4 transmits an audio signal, a video signal, and a control signal to and from the signal transmission unit 101 of the parent device M via the signal line Ls. The signal transmission unit 4 also performs encoding (compression) processing of the video signal and modulation processing for digitally modulating the encoded video signal (for example, BPSK and QPSK).

  The operation input unit 7 has a large number of push button switches. When these push button switches are turned on, the operation input unit 7 accepts operation inputs corresponding to the push button switches, and sends an operation signal corresponding to the received operation input to the control unit 8. Send it out. The operation input unit 7 also includes a display (for example, a 7-segment LED display) for displaying input contents as will be described later.

  The control unit 8 includes hardware such as a microcomputer and a memory, and software for executing various controls described later. For example, when an operation input for calling the base unit M is received by the operation input unit 7, the control unit 8 transmits a call signal from the signal transmission unit 4 to the base unit M via the signal line Ls. Then, a ringing tone is generated from the speaker of the base unit M that has received the calling signal. Further, when the response button of the base unit M is operated within a predetermined time after the ringing tone is sounded, a communication path via the signal line Ls is formed between the base unit M and the handset S, and the base unit M Interphone call is possible between the mobile phone S and the handset S. That is, in this embodiment, the handset S used by a visitor for a call corresponds to an image pickup apparatus and an interphone device provided with the image pickup apparatus. The system is configured.

  FIG. 2 shows an external view (front view) of the handset S configured as a lobby intercom. The housing 200 of the slave unit S is formed in a rectangular box shape when viewed from the front, and includes an imaging unit 1, a buffer memory 2, an image processing unit 3, a signal transmission unit 4, a face detection processing unit 5, and an angle of view adjustment. The unit 6, the operation input unit 7, and the control unit 8 are accommodated. In the center of the front surface of the housing 200, operation members (operation buttons) 201 and 202 for pressing the push button switch of the operation input unit 7 are disposed. One operation button 201 corresponds to a push button switch for inputting a number from 0 to 1 or * (asterisk) and a push button switch for deleting the inputted number or asterisk. Further, the other operation button 202 determines the contents inputted by operating the operation button 201 (the dwelling unit number of the dwelling unit in which the parent device M is installed), and transmits a calling signal from the child device S to the parent device M. This corresponds to a push button switch. The contents (numerals) input by pressing the operation button 201 are displayed on a display (for example, a 7-segment LED display) 203 disposed on the operation button 201 on the front surface of the housing 200. Is done. Further, the lens 11 of the imaging unit 1 is disposed next to the display 203 on the front surface of the housing 200. However, the lens 11 is hidden by a cover 204 made of frosted glass. The position where the lens 11 is disposed may be a position where the face of the visitor who presses the operation button 201 can be imaged.

  Next, with reference to the time chart of FIG. 3, an operation until the visitor calls the parent device M of the visited dwelling unit using the child device S will be described. First, a visitor stands in front of the handset S and presses the operation button 201 to input the dwelling unit number of the visited dwelling unit. The operation input unit 7 outputs an operation signal corresponding to the push button switch pressed by the operation button 201 to the control unit 8 every time the operation button 201 is pressed. The control unit 8 determines that there is a high possibility that a person (visitor) is within the imaging range of the imaging unit 1 when the first operation signal is received from the operation input unit 7.

  Then, after determining that there is a high possibility that a person is in the imaging range, the control unit 8 activates the imaging unit 1 to perform imaging, and instructs the face detection processing unit 5 to execute face detection processing. Further, the control unit 8 stores (buffers) image data in the buffer memory 2 with a period TB (TB = TF × 5 in the illustrated example) longer than the frame period TF of the imaging unit 1. Here, before the operation button 201 is operated by the visitor, the imaging unit 1, the buffer memory 2, the image processing unit 3, the signal transmission unit 4, the face detection processing unit 5, and the view angle adjustment unit 6 are in a pause state. Only the operation input unit 7 and the control unit 8 are operating. However, the control unit 8 is in a standby state in which the power consumption of the microcomputer is suppressed, and returns to a normal operation state when the first operation signal is received from the operation input unit 7.

  The face detection processing unit 5 performs a face detection process on the image captured by the image capturing unit 1 to detect a region (face existing region) in which a visitor's face is shown, and the position of the detected face existing region Information is passed to the control unit 8. The control unit 8 determines whether or not the enlargement process in the image processing unit 3 is necessary based on the position information of the face existing area received from the face detection processing unit 5. For example, if the visitor is at a position away from the child device S and the ratio of the face existing area to the screen is equal to or less than a predetermined threshold, the control unit 8 determines that the enlargement process is necessary and determines the image. The processing unit 3 is instructed to execute enlargement processing. On the other hand, if the visitor is approaching the face of the child device S and the ratio of the face existing area to the screen exceeds the threshold value, the control unit 8 determines that the enlargement process is unnecessary, and the image processing unit 3 Is not instructed to execute enlargement processing.

  Further, when receiving the position information of the face existing area from the face detection processing unit 5, the control unit 8 causes the image processing unit 3 to start tracking processing and adjustment processing. This tracking process is performed by a plurality of frames of images stored in the buffer memory 2 from the start of operation of the operation buttons 201 and 202 to the end of the face detection process of the face detection processing unit 5 (face detection process period TX). Start with data. However, the first stored frame is not used for the tracking process, but only for the face detection process. Furthermore, when the processing of the image data stored in the buffer memory 2 is completed during the face detection processing period TX, the image processing unit 3 subsequently uses the latest image data stored in the buffer memory 2 to perform the tracking process. Continue. Note that after the processing of the image data stored during the face detection processing period TX is completed, the control unit 8 makes the buffering cycle TB of the buffer memory 2 coincide with the frame cycle TF of the imaging unit 1. Therefore, all the image data output from the imaging unit 1 is stored in the buffer memory 2 in order.

  Then, based on the position of the moving object (visitor) on the image detected by the tracking process, the image processing unit 3 performs an imaging range or enlargement process of the imaging unit 1 so that the face existing area does not deviate from the image (view angle). The enlargement area at is adjusted (adjustment process). Further, the image processing unit 3 executes enlargement processing, tracking processing, and adjustment processing in accordance with instructions from the control unit 8, and when the processed image (video signal) or any processing is not executed, the original image (video Signal) is modulated and output to the signal transmission unit 3. Therefore, an image (video) in which the face of the visitor is shown in an appropriate size is displayed on the display unit 101 of the parent device M.

  When the operation button 202 of the operation input unit 7 is pressed, the control unit 8 determines the number sequence indicated by the operation signal received from the operation input unit 7 so far as the dwelling unit number, and the dwelling unit number is assigned. The control signal (calling signal) is transmitted from the signal transmission unit 3 to the parent device M. Further, the control unit 8 instructs the image processing unit 3 and the signal transmission unit 4 to transmit an image.

  On the other hand, when the base unit M receives a control signal (calling signal) matching the dwelling unit number assigned to itself at the signal transmission unit 100, the base unit control unit 102 sounds a ringing tone from the speaker. Further, the image transmitted from the slave unit S is received by the signal transmission unit 100 and the image is displayed on the display unit 101 of the master unit M.

  As described above, in the slave unit S, the image processing unit 3 performs adjustment processing on the image data stored in the buffer memory 2 during the face detection processing of the face detection processing unit 5. Therefore, even if the hardware constituting the image processing unit 3 and the face detection processing unit 5 is not high-performance and it takes a relatively long time for the face detection processing, the face of the person is reliably tracked. An image can be taken and an increase in manufacturing cost can be suppressed.

  By the way, it is highly likely that a visitor who presses the operation buttons 201 and 202 of the handset S is reflected in the image subjected to the face detection processing by the face detection processing unit 5. In the following, for the sake of simplicity, a short-time image on which face detection processing has been performed as described above will be referred to as an “intro image”. The intro image is stored in a memory (not shown) different from the buffer memory 2.

  In the conventional intercom system, a real-time image captured after a call operation is performed on the slave unit is displayed on the monitor of the master unit. For this reason, the visitor who has finished the call operation is unconsciously or intentionally deviated from the imaging range of the imaging unit 1 and is displayed on the display unit 101 of the main unit M at the time when the resident (responder) who heard the ringing sound watches. There were cases where visitors were not shown in the image. On the other hand, in the present embodiment, visitors who move to some extent can be accommodated within the imaging range of the imaging unit 1 by the tracking process and the adjustment process of the image processing unit 3.

  Here, in the response waiting period (hereinafter referred to as “intro period”) from when the ringing tone is sounded until the response button is operated, the intro image and the real-time image are distributed to the main screen and the sub screen. You may display on the display part 101 of the main | base station M simultaneously. That is, the image processing unit 3 of the child device S executes parent-child screen processing, combines the intro image stored in the memory and the real-time image (image after adjustment processing), and sets one image as the parent screen, An image that simultaneously displays the other image as a child screen in the same screen is created. Then, the image of the parent-child screen created by the image processing unit 3 is transmitted from the signal transmission unit 4 to the parent device M, and two types of images (intro image I2 and real-time image I1) are displayed on the display unit 101 of the parent device M. Displayed as a parent-child screen. When an operation input for switching the parent / child screen is received by the operation input unit 103 of the parent device M, the parent device control unit 102 causes the signal transmission unit 100 to transmit a control signal instructing switching of the parent / child screen. The control unit 8 of the child device S that has received the control signal instructs the image processing unit 3 to switch (replace) the image displayed on the parent screen and the image displayed on the child screen. As a result, the position of the image on the parent / child screen displayed on the display unit 103 of the parent device M is switched. That is, in this embodiment, the image processing unit 3 corresponds to an image generation unit, and the control unit 8 corresponds to an output unit. However, it is also possible for the master unit control unit 102 of the master unit M to combine and replace the master screen and the slave screen.

  Here, even when the control unit 8 transmits only the intro image from the signal transmission unit 4 according to the control signal, the image processing unit 3 continues the tracking process and the adjustment process. Therefore, when the control unit 8 switches the image to be transmitted from the signal transmission unit 4 from the intro image to a real-time image or a parent-child image including a real-time image, the adjusted real-time image can be transmitted immediately.

M Interphone main unit (interphone device)
S Interphone cordless handset (imaging device, intercom device)
1 Imaging unit (imaging means)
2 Buffer memory (memory means)
3 Face detection processing unit (face detection means)
4 Image processing unit (enlarging means, adjusting means)

Claims (7)

  Imaging means for picking up an image, storage means for storing the image, face detection means for detecting a human face existing area in the image, enlargement means for enlarging a partial area of the image, and the person Adjustment means for adjusting an imaging range of the imaging means or an enlargement area of the enlargement means so as not to deviate from the image, and the image stored in the storage means during the detection process of the face detection means The image pickup apparatus is characterized in that adjustment processing of the adjustment means is performed.   The imaging apparatus according to claim 1, wherein the storage unit stores an image at a constant period.   The storage means stores an image with a first period longer than the frame period of the imaging means when a person is likely to be within the imaging range of the imaging means, and at other times than the first period. The imaging apparatus according to claim 2, wherein the image is stored in a second period that is shorter and not longer than the frame period.   The apparatus according to claim 1, further comprising an image generation unit configured to generate an image in which a plurality of types of images including images adjusted by the adjustment unit are distributed to a main screen and a sub screen. Imaging device.   Output means for selecting and outputting an image adjusted by the adjustment means and an image not adjusted by the adjustment means, the adjustment means regardless of whether the output means is selected or not The imaging apparatus according to any one of claims 1 to 4, wherein the adjustment is performed.   An intercom apparatus comprising: the imaging apparatus according to claim 1; and a transmission unit that transmits an image captured by the imaging apparatus.   An intercom system comprising: the intercom apparatus according to claim 6; and an intercom apparatus including display means for displaying an image transmitted from the intercom apparatus.

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