Recording/reproducing device, recording/reproducing method, and program for movable object and recording and reproducing captured by camera

A recording/reproducing device includes a captured data acquisition unit that acquires captured data, an event detection unit that detects occurrence of an event on a movable object, a recording control unit, a display unit that displays a video contained in event recording data, a line-of-sight detection unit, and a reproduction control unit. The recording control unit stores, as event recording data, the captured data for a predetermined period from at least part of the captured data on the basis of detection of an event. The line-of-sight detection unit detects that a user's line of sight is pointing towards the display unit. The reproduction control unit starts reproduction of the event recording data when it is detected that the user's line of sight is pointing towards the display unit within a predetermined period after detection of the event.

BACKGROUND

The present invention relates to a recording/reproducing device, recording/reproducing method, and program.

A dashboard camera that includes a means of taking pictures of the situation around a vehicle and acquiring data such as a video and a means of detecting that the vehicle has received some impact, and stores, in a reproducible manner, a video or the like for a predetermined period of time on the basis of the point of time when an impact on the vehicle is detected is widely used. For example, Japanese Unexamined Patent Application Publication No. 2009-087007 discloses a dashboard camera that records video data on the basis of the transition of acceleration. When an event such as an accident is detected, this dashboard camera stores the situation of the accident in a reproducible manner. Further, when abnormal acceleration due to dangerous driving or the like is detected, the dashboard camera stores the situation of the dangerous driving in a reproducible manner.

SUMMARY

However, not a few users of a dashboard camera do not fully know how to operate the dashboard camera. Further, when an event such as an accident is detected, a user cannot instantly perform a complicated operation. Thus, a user cannot appropriately reproduce a video or the like of an event stored in the dashboard camera in some cases.

The present embodiments have been accomplished to solve the above problems and an object of the embodiments is thus to provide a recording/reproducing device and the like that reproduce stored data without a complicated operation.

A recording/reproducing device according to an embodiment is a recording/reproducing device placed in a movable object and recording and reproducing captured data captured by a camera, the device including a captured data acquisition unit configured to acquire the captured data, an event detection unit configured to detect occurrence of an event on the movable object, a recording control unit configured to store, as event recording data, the captured data for a predetermined period from at least part of the captured data on the basis of detection of the event, a line-of-sight detection unit configured to detect that a user's line of sight is pointing towards a display unit configured to display the event recording data, and a reproduction control unit configured to start reproduction of the event recording data when the line-of-sight detection unit detects that a line of sight is pointing towards the display unit within a predetermined period after detection of the event.

A recording/reproducing method according to an embodiment is a recording/reproducing method of recording and reproducing captured data captured by a camera placed in a movable object, and it includes a captured data acquisition step, an event detection step, a recording control step, a line-of-sight detection step, and a reproduction control step. The captured data acquisition step acquires captured data captured by a camera placed in a movable object. The event detection step detects occurrence of an event on the movable object. The recording control step stores, as event recording data, the captured data for a predetermined period from at least part of the captured data on the basis of detection of the event. The line-of-sight detection step detects that a user's line of sight is pointing towards a display unit for displaying the event recording data. The reproduction control step starts reproduction of the event recording data when the line-of-sight detection step detects that a line of sight is pointing towards the display unit within a predetermined period after detection of the event.

A program according to an embodiment is a program to be executed by a computer to put a recording/reproducing device into operation. The recording/reproducing method includes a captured data acquisition step, an event detection step, a recording control step, a line-of-sight detection step, and a reproduction control step. The captured data acquisition step acquires captured data captured by a camera placed in a movable object. The event detection step detects occurrence of an event on the movable object. The recording control step stores, as event recording data, the captured data for a predetermined period from at least part of the captured data on the basis of detection of the event. The line-of-sight detection step detects that a user's line of sight is pointing towards a display unit for displaying the event recording data. The reproduction control step starts reproduction of the event recording data when the line-of-sight detection step detects that a line of sight is pointing towards the display unit within a predetermined period after detection of the event.

This embodiment provides a recording/reproducing device and the like that reproduce stored data without a complicated operation.

DETAILED DESCRIPTION

The following description and the attached drawings are appropriately shortened and simplified to clarify the explanation. In the figures, the identical reference symbols denote identical structural elements and the redundant explanation thereof is omitted according to need.

First Embodiment

A configuration according to a first embodiment is described hereinafter with reference to the drawings. A recording/reproducing device10according to this embodiment is used by being placed in a vehicle such as an automobile, which is a movable object, and records and reproduces captured data that has been taken by a camera, and it is a device called a dashboard camera, for example. The recording/reproducing device10has a function of, when a sudden impact or the like is applied, recording captured data for a predetermined period in such a way that it is reproducible as “event recording data”, triggered by the applied impact. A driver or the like of the automobile reproduces this event recording data and views a video of the reproduced event recording data, and thereby grasps the situation of the event.

FIG. 1is a block diagram showing the configuration of a recording/reproducing device according to the first embodiment. As shown therein, the recording/reproducing device10includes a control unit100that controls each component and a plurality of components connected to the control unit100. The control unit100is a control device that includes a circuit board on which a CPU (Central Processing Unit), a GPU (Graphics Processing Unit) memory, a plurality of interfaces and the like are mounted, and it executes a stored program and executes various processing.

The details of the control unit100are described hereinbelow. The control unit100includes a captured data acquisition unit120, a buffer memory121, a captured data processing unit122, a recording control unit123, a reproduction control unit124, an operation control unit125, a display control unit126, an event detection unit127, a location information acquisition unit128, a timer129, a line-of-sight detection unit130, and a light emission control unit131, and those elements of performing processing and control are implemented by a program executed by the control unit100. For the sake of convenience, those elements are represented in such a way that each of them is connected to a bus line110.

The captured data acquisition unit120acquires captured data that is supplied from a camera150. The captured data acquisition unit120supplies the captured data to the buffer memory121through the bus line110. Further, the captured data acquisition unit120acquires captured data that is supplied from a line-of-sight detection camera151, and supplies the acquired captured data to the line-of-sight detection unit130.

The buffer memory121is a volatile or non-volatile memory device. The buffer memory121sequentially receives captured data generated periodically by the camera150through the captured data acquisition unit120, and temporarily stores the received captured data. The captured data temporarily stored in the buffer memory121is data for a predetermined period. The buffer memory121sequentially erases the captured data after the predetermined period of time has elapsed or sequentially overwrites them with newly received captured data.

The captured data processing unit122generates a captured file in a format conforming to predetermined specifications from the captured data stored in the buffer memory121. The predetermined specifications are specifications such as H.264 or MPEG-4 (Moving Picture Experts Group), for example.

Note that the captured data processing unit122may generate a captured file with a predetermined angle of view by processing captured data. Further, the captured data processing unit122may generate a captured file by processing captured data output from the buffer memory121, generating captured data for a predetermined length of time or with a predetermined angle of view, and adding header information or the like such as a file name. Further, the captured data processing unit122may process captured data output from the buffer memory121and perform noise removal, distortion correction and the like of the captured data, or may generate a captured file in which time information, vehicle speed information, vehicle location information and the like are displayed on the captured data.

The recording control unit123performs control to store the captured file generated by the captured data processing unit122into a recording device160. When the event detection unit127detects an event, the recording control unit123stores, into the recording device160, a captured file for a predetermined period as event recording data that is not overwritable on the basis of the detection of an event. The recording control unit123stores the event recording data into a predetermined recording area in the recording device160. The predetermined recording area is a storage area that is protected from overwrite or erasure, for example. Alternatively, the event recording data that is supplied from the recording control unit123to the recording device160may be stored with a flag indicating protection from overwrite or erasure contained in a file.

Further, the recording control unit123records, into the recording device160, information indicating whether the event recording data stored in the recording device160has been reproduced by the reproduction control unit124in the past. The reproduction control unit124thereby identifies which event recording data has not been reproduced.

Note that, when the event detection unit127does not detect any event, the recording control unit123may store the captured file in an overwritable state into the recording device160. A captured file that is stored in the recording device160and different from the event recording data is referred to hereinafter as a “normal file”. When the recording device160reaches its maximum capacity, the recording control unit123may erase the oldest normal file and record a newly generated normal file into the recording device160.

The reproduction control unit124performs processing for reproducing the stored event recording data under a preset condition. The preset condition is the case where it is detected that a user's line of sight is pointing towards a display unit41within a predetermined period of time after an event is detected. In this case, the reproduction control unit124receives, from the line-of-sight detection unit130, a signal indicating that a user's line of sight is pointing towards the display unit141.

The reproduction control unit124monitors the timer129and determines whether a predetermined period of time has elapsed after detection of an event. When reproducing the event recording data, the reproduction control unit124reads the event recording data stored in the recording device160, and supplies the read event recording data to the display control unit126. Note that the above-described predetermined period of time is an appropriate period of time, such as 1, 3, or 5 minutes, for example, to make a request for reproducing the event recording data after the occurrence of an event such as an accident in order to check the event.

The reproduction control unit124starts reproducing the event recording data when it detects that a user's line of sight is pointing towards the display unit141within a predetermined period of time after an event is detected, which is the time when the event is detected. The reproduction control unit124may start reproducing the event recording data when it detects that a user's line of sight is pointing towards the display unit141within a predetermined period of time after an event is detected and storing of the event recording data is done. Further, when the reproduction control unit124detects that a user's line of sight is pointing towards the display unit141before storing of the event recording data is done, it may start reproducing the stored event recording data after storing of the event recording data is done, or may start reproducing the event recording data before storing of the event recording data is done if reproduction of the event recording data is possible.

The operation control unit125acquires operation information received by an operation unit140, and outputs an operation instruction based on the operation information to each component. When the operation control unit125acquires an instruction of selecting data to be reproduced from the operation unit140, it causes the reproduction control unit124to select a file or the like recorded in the recording device160. When the operation control unit125acquires an instruction related to reproduction of data from the operation unit140, it causes the reproduction control unit124to perform processing related to reproduction. The instruction related to reproduction of data is reproduction start, pause, reproduction stop, zoom display and the like, for example.

The display control unit126controls the display unit141to display various information. For example, the display control unit126causes the display unit141to display captured data which the camera150is taking. Further, the display control unit126receives the event recording data supplied from the reproduction control unit124, and causes the display unit141to display the received event recording data. When the display unit141is provided with a touch sensor as a function of the operation unit140, the display control unit126causes the display unit141to display an icon or the like corresponding to the touch sensor as appropriate.

The event detection unit127receives information related to acceleration detected by an acceleration sensor142, and detects the occurrence of a specified event from a signal size or a signal pattern of the received information. Externally applied acceleration is acceleration that is applied to the recording/reproducing device10from the outside, and it is acceleration caused by an impact or the like that occurs when an automobile collides with another object, for example.

When the event detection unit127detects that the information received from the acceleration sensor142corresponds to the occurrence of a specified event, it supplies a signal indicating that the occurrence of an event is detected to the captured data processing unit122. The occurrence of an event is the case where acceleration that occurs in the event of an accident such as an impact caused by sudden braking or an impact when an object hits a vehicle, for example, is detected. The event detection unit127detects the occurrence of an event when acceleration towards a predetermined direction exceeding a predetermined value is detected for a period exceeding a predetermined period of time or when there is a significant change in acceleration during a predetermined period of time, for example. Note that the event detection unit127may detect acceleration in x-axis, y-axis and z-axis, which are coordinate axes in a 3-axis coordinate system, or may detect acceleration in at least one direction among them. Further, weights may be assigned to acceleration received from the 3-axis directions. The event detection unit127supplies a signal indicating that occurrence of an event is detected also to the timer129.

The location information acquisition unit128receives a signal from a GPS satellite received by a GPS (Global Positioning System) receiving unit143, acquires location information, which is information about the current location from the received signal, and supplies the acquired location information to the recording control unit123. The location information contains the latitude and longitude of a vehicle at the time when the signal is received from the GPS satellite, for example.

The timer129receives a signal indicating that the occurrence of an event is detected from the event detection unit127, and on the basis of this signal as a trigger signal, resets a count value of the timer and activates itself. Once activated, the timer129counts up to the predetermined period.

The line-of-sight detection unit130receives the captured data acquired from the line-of-sight detection camera151by the captured data acquisition unit120, and detects that a user's line of sight is pointing towards the display unit141from the received captured data. The line-of-sight detection unit130detects a line of sight by recognizing the positions of eyes included in the user's face from the received captured data and analyzing the motion of the pupils and the Purkinje images in the detected eyes. Note that line-of-sight detection technology is widely known to those skilled in the art, and the detailed description thereof is omitted.

The line-of-sight detection unit130receives captured data corresponding to the frame rate (e.g., 30 frames per second) of the line-of-sight detection camera151from the captured data acquisition unit120. An example of the case of detecting that a user's line of sight is pointing towards the display unit141is when a user's line of sight is pointing towards the display unit141continuously for a predetermined period of time (e.g., 1 second). Another example of the case of detecting that a user's line of sight is pointing towards the display unit141is when a user's line of sight is pointing towards the display unit141at a frequency of 80 percents or more of a predetermined period of time (e.g., 1.5 seconds). In this manner, when the frequency that a user's line of sight is pointing towards the display unit141is high during a predetermined period of time, the line-of-sight detection unit130supplies a signal indicating that the user's line of sight is pointing towards the display unit141to the reproduction control unit124.

The light emission control unit131is a driver that controls a light emitting device152. The light emission control unit131supplies a signal for lighting the light emitting device152to the light emitting device152when performing line-of-sight detection.

Each of elements that are connected to the control unit100is described hereinafter. The recording/reproducing device10includes the operation unit140, the display unit141, the acceleration sensor142, the GPS receiving unit143, the camera150, the line-of-sight detection camera151, the light emitting device152, and the recording device160.

The operation unit140is a user interface for receiving a user's operation on the recording/reproducing device10. The user interface may be an operation button or a touch sensor placed on the display unit141, for example. Further, the user interface may be a receiving unit of infrared rays or radio communication, and it may receive a signal transmitted from a remote control or the like. The operation unit140supplies operation information, which is information about a received operation, to the control unit100through a specified interface. The operation information is an instruction for starting event recording or an instruction for reproducing event recording data, for example.

The display unit141is a display device that displays various information by control of the display control unit126. The display unit141at least includes a display panel such as a liquid crystal panel or an organic EL (Electro Luminescence), for example. The display unit141connects to the display control unit126and displays a signal supplied from the display control unit126. The display unit141is configured to display a video contained in the event recording data.

The acceleration sensor142is a 3-axis acceleration sensor, for example, and it is placed in an arbitrary position of the recording/reproducing device10. The acceleration sensor142detects acceleration applied to the acceleration sensor142, and supplies information about the detected acceleration to the control unit100according to the detected acceleration. The acceleration sensor142connects to the event detection unit127and supplies information about the detected acceleration to the event detection unit127. Note that the state about acceleration that is supplied from the acceleration sensor142to the control unit100can be used also by another element and, to be more specific, the reproduction control unit124also uses the information about acceleration received from the acceleration sensor142. Note that the acceleration sensor142may be a 1-axis or 2-axis acceleration sensor instead of a 3-axis acceleration sensor.

The GPS receiving unit143receives information about the current location of a vehicle by a satellite positioning system called GPS or GNSS (Global Navigation Satellite System). The GPS receiving unit143may be an antenna for receiving a GPS signal or a communication interface for receiving location information acquired by a vehicle. The GPS receiving unit143supplies a signal about the received current location to the location information acquisition unit128.

The camera150is an imaging device that includes an objective lens, an imaging element, an A-D (Analog to Digital) conversion element and the like.

The camera150captures video images containing the view around a vehicle, which is a movable object, and generates captured data, which is data of the captured video images. The camera150supplies the generated captured data to the captured data acquisition unit120.

The line-of-sight detection camera151is an imaging device for detecting a user's line of sight included in a captured user's face. The line-of-sight detection camera151captures video images of a user's face and generates video data, which is data of the captured video images. The line-of-sight detection camera151supplies the generated video data to the captured data acquisition unit120.

The light emitting device152is a device that emits light for line-of-sight detection, and it is a LED (light-emitting diode), for example. The light emitting device152emits infrared light with a wavelength of 850 nanometers, for example, towards the imaging range of the line-of-sight detection camera151. The light emitting device152emits infrared light and the line-of-sight detection camera151captures images of eyeballs of the user on which the infrared light is reflected, and thereby detects the user's line-of-sight.

The recording device160is a recording device that stores captured data supplied from the camera150. The recording device160is a memory card including a flash memory or a nonvolatile recording device such as an SSD (Solid State Drive) or an HDD (Hard Disc Drive), for example. The recording device160connects to the recording control unit123, receives specified data from the recording control unit123, and records the received data. Further, the recording device160supplies an event file containing the recorded event recording data to the reproduction control unit124in response to an instruction from the reproduction control unit124. The recording device160may be configured to be detachable or undetachable from the recording/reproducing device10.

A mechanical configuration of the recording/reproducing device10is described hereinafter with reference toFIGS. 2 to 4.FIG. 2is a right side view of the recording/reproducing device10according to the first embodiment.FIG. 3is a back view of the recording/reproducing device10according to the first embodiment, which is viewed from the imaging direction.FIG. 4is a front side view of the recording/reproducing device10according to the first embodiment, which is viewed from the display direction. Note that, for the convenience of illustrating the positional relationship of the components, a right-handed orthogonal coordinate system is shown inFIGS. 2 to 4. Further, when an orthogonal coordinate system is shown in the following figures, the x-axis, y-axis, and z-axis directions ofFIGS. 2 to 4and the x-axis, y-axis, and z-axis directions of the orthogonal coordinate system respectively coincide with each other.

As shown inFIG. 2, the recording/reproducing device10is fixed to a wind shield (WS) of a vehicle through a bracket900. The bracket900includes a bonding part901, a holding part902, and a ball joint903.

The bonding part901is a member where an adhesive is applied onto the surface in contact with the wind shield WS. The bonding part901is bonded to an arbitrary position of the wind shield WS, which allows the bracket900to be fixed.

The holding part902is attachable/detachable from an attach/detach part921of the recording/reproducing device10and fits this part to prevent that the mounted recording/reproducing device10comes off while the vehicle is moving or displacement of the shooting direction occurs. For example, the holding part902has a rib or a groove that is slidably engaged with the attach/detach part921of the recording/reproducing device10in a specified direction, and when it is slid by a specified dimension, it is locked by a lock mechanism (not shown) and fixed tight.

The ball joint903is a joint mechanism that is placed to adjust the angle between the bonding part901and the holding part902, and it moves when a specified external force acts. In the state where the bonding part901is bonded to the wind shield WS and the holding part902fits the recording/reproducing device10, the ball joint903does not move unless a specific external force is applied.

A user who uses the recording/reproducing device10bonds the bonding part901to the wind shield WS and also causes the holding part902to fit the attach/detach part921of the recording/reproducing device10. The recording/reproducing device10is thereby fixed to the vehicle.

It should be noted that, when removing the recording/reproducing device10fixed to the vehicle, a user releases the attach/detach part921of the recording/reproducing device10from the holding part902. When releasing the attach/detach part921from the holding part902, a user unlocks the lock mechanism (not shown) and slides the attach/detach part921to separate off the holding part902. The recording/reproducing device10is thereby detached from the vehicle, and a user can hold the recording/reproducing device10.

As shown inFIGS. 2 to 4, the recording/reproducing device10has a substantially rectangular parallelepiped shape in which the front side and the backside are the principal surfaces of a rectangle and the thickness is about a fraction of the length of the short sides of the rectangle projected from the front side. The recording/reproducing device10is covered with a case920made of resin.

The recording/reproducing device10has an objective lens of the camera150which is uncovered and visible from the outside on its back face, and also has the attach/detach part921on its top face. Thus, the attach/detach part921on the top surface of the recording/reproducing device10fits the holding part of the bracket900, and thereby the recording/reproducing device10is fixed to the vehicle with the objective lens of the camera150visible from the outside in the travelling direction of the vehicle. The front face of the recording/reproducing device10faces the user side in the state where it is fixed to the vehicle in this manner. On the front face of the recording/reproducing device10are placed a display panel of the display unit141, the line-of-sight detection camera151, and the light emitting device152. The recording/reproducing device10is installed in this way, and thereby the recording/reproducing device10captures video images the travelling direction and displays the captured video to the user. The display unit141shown inFIG. 4is in the state of displaying the event recording data.

Further, the recording/reproducing device10has the line-of-sight detection camera151and the light emitting device152on the display surface side of the display unit141. In this structure, the emitting device152emits infrared light to the user's face facing the display unit141, and the line-of-sight detection camera151captures images of the user's face irradiated with infrared light. The size of the display panel of the recording/reproducing device10is 1.5 to 4 inches in the diagonal line, for example. Further, the size of the case920is about 5 to 10 centimeters in the width direction (x-axis direction), for example.

Captured data is described hereinafter with reference toFIG. 5.FIG. 5is a first view showing the relationship between captured data stored in the recording/reproducing device and time. The horizontal axis of the figure indicates time, and it shows that the time elapses in the direction of the arrow (rightward) from time t10to time t11.

The elongated shape shown along the time axis is captured data C11at time t11. The captured data C11is captured data generated by the camera150and stored in the buffer memory121. The recording/reproducing device10is configured to constantly store the captured data for a predetermined period Pn. The period Pn is a period of 60, 120, or 150 seconds, for example. The captured data C11at time t11is captured data from time t10, which precedes time t11by the period Pn, to time t11. Further, in the buffer memory121, the past captured data that is older than the period Pn is sequentially erased with the lapse of time.

The example shown inFIG. 5assumes that the recording/reproducing device10detects the occurrence of an event at time t11. Thus, the recording/reproducing device10performs processing of generating event recording data, using time t11as a reference.

Captured data and event recording data after the occurrence of an event is detected is described hereinafter with reference toFIG. 6.FIG. 6is a second view showing the relationship between captured data stored in the recording/reproducing device and time.FIG. 6shows the structure of data at time t21, which is later than time t11. Data stored in the buffer memory121at time t21is captured data C21from time t20, which precedes time t21by the period Pn, to time t21.

The rectangle shown under the captured data C21is event recording data E11. The event recording data E11is extracted from the captured data according to an event detected at time t11. In this embodiment, using time t11when an event is detected as a reference, the recording/reproducing device10sets time ts, which precedes time t11by the period P1, as the start time of the event recording data. Further, in this embodiment, the recording/reproducing device10sets time te, at which a period P2has elapsed from the time t11when an event is detected as a reference, as the end time of the event recording data. The period P1and the period P2are periods of 10, 15, or 20 seconds, for example. Specifically, the recording/reproducing device10stores the captured data for the period from time ts to time te as the event recording data E11.

By generating the event recording data as described above, the recording/reproducing device10is able to record the captured data for the period before and after the event occurred. This allows a user to visually check the situation around the vehicle before and after the occurrence of the event by reproducing the event recording data stored by the recording/reproducing device10after the occurrence of the event.

Note that the recording/reproducing device10may record a normal file, in addition to the event recording data, into the recording device160. In this case, the recording/reproducing device10extracts captured data for a specified period from the captured data stored in the buffer memory121, and records the extracted captured data as a normal file into the recording device160. The recording/reproducing device10may perform processing of recording a normal file and processing of storing event recording data in parallel.

A process that is performed by the recording/reproducing device10is described hereinafter with reference toFIG. 7.FIG. 7is a flowchart in the case where the recording/reproducing device detects the occurrence of an event.FIG. 7shows the process that is performed by the control unit100in the case where the recording/reproducing device10detects an event. The flowchart ofFIG. 7is started under arbitrary conditions, such as when power is supplied from a vehicle to the recording/reproducing device10at the operation start of the vehicle or the like.

First, the control unit100starts acquiring captured data (Step S10). In Step S10, the control unit100also starts detecting an event. The captured data is supplied from the camera150at regular time intervals (e.g., 30 flames per second). The captured data acquisition unit120supplies the captured data supplied from the camera150to the buffer memory121. The buffer memory121stores the captured data of a predetermined period (e.g. 60 seconds), and after the captured data of a predetermined period is stored, sequentially deletes old captured data and stores new captured data.

Next, the event detection unit127determines whether the occurrence of an event is detected from information supplied from the acceleration sensor142(Step S11). When it is determined that the occurrence of an event is detected (Step S11: Yes), the recording control unit123generates event recording data and records it into the recording device160(Step S12). On the other hand, when it is not determined that the occurrence of an event is detected in Step S11(Step S11: Yes), the control unit100proceeds to Step S13without generating the event recording data.

Then, the control unit100determines whether to end the process (Step S13). When it is not determined to end the process (Step S13: No), the control unit100returns to Step S11and determines whether the occurrence of an event is detected again. On the other hand, when it is determined to end the process (Step S13: Yes), the control unit100ends the process.

An event recording data reproduction process that is performed by the control unit100is described hereinafter with reference toFIG. 8.FIG. 8is a flowchart in the case where the recording/reproducing device reproduces event recording data. The process ofFIG. 8is started when Step S11in the process ofFIG. 7results in Yes, that is, when an event is detected.

First, upon detection of an event, the reproduction control unit124resets a count value of the timer129(Step S110), and then starts the timer129(Step S111). Note that the timer129increments the count value sequentially with the lapse of time. Next, the reproduction control unit124reads the count value of the timer129and determines whether the count value has reached the period PX (Step S112). When it is determined that the count value has reached the period PX (Step S112: Yes), the control unit100ends the process shown inFIG. 8.

When, on the other hand, it is not determined that the count value has reached the period PX in Step S112(Step S112: No), the reproduction control unit124determines whether a user's line of sight is pointing towards the display unit141from a signal related to line-of-sight detection received from the line-of-sight detection unit130(Step S113).

When it is not determined that the user's line of sight is pointing towards the display unit141(Step S113: No), the control unit100determines whether the count value has reached the period PX again in Step S112. On the other hand, when it is determined that the user's line of sight is pointing towards the display unit141in Step S113(Step S113: Yes), the reproduction control unit124stops counting the timer129(Step S114), and starts reproducing the event recording data to be reproduced (Step S115). The event recording data to be reproduced is the event recording data stored in the process ofFIG. 7on the basis of the event that has triggered the start of the process inFIG. 8, which is the event recording data stored most recently when the line of sight has pointed towards the display unit.

Next, the reproduction control unit124determines whether to end the reproduction of the event recording data (Step S116). To be specific, the reproduction control unit124detects whether the operation control unit125that receives a user's operation has received an operation to stop the reproduction of event recording data. When the reproduction ending operation is not received (Step S116, No), the control unit100continues the reproduction of event recording data. On the other hand, when the reproduction ending operation is received (Step S116, Yes), the reproduction control unit124performs processing of ending the reproduction of event recording data (Step S117), and thereby ends the process shown inFIG. 8.

The event recording data reproduction process performed by the control unit100is described above. In the above process, Step S114and Step S115may be interchanged or may be performed simultaneously.

When starting reproducing event recording data in Step S115, display that prompts a user to perform an operation of permitting the start of reproduction may be shown, and reproduction of event recording data may be started when a user's permission is given. This allows the recording/reproducing device10to reproduce event recording data according to a user's intention without need of a complicated operation.

The first embodiment is described above. In the above configuration, when a user's line of sight is pointing towards the display unit141before the predetermined period PX has elapsed after the occurrence of a specified event, the recording/reproducing device10reproduces the most recent event recording data. This allows a user to check the event recording data by looking at the display unit of the recording/reproducing device immediately after the occurrence of an event such as an accident, for example. Therefore, according to the first embodiment, there are provided a recording/reproducing device and the like that reproduce stored data without a complicated operation.

Modified Example of First Embodiment

A modified example of the first embodiment is described hereinafter. In a recording/reproducing device according to the modified example of the first embodiment, a recording device that at least includes the camera150and the captured data acquisition unit120that generate captured data and a reproducing device that at least includes the line-of-sight detection camera151and the display unit141are separated.

FIG. 9is an overview of a recording/reproducing device according to a modified example of the first embodiment. As shown in the figure, the recording/reproducing device10includes a recording unit20and a reproducing unit30. The recording unit20shown in the upper part of the figure includes a camera150and an attach/detach part921, and it is fixed to a bracket900and captures the scene in the traveling direction of the vehicle. The reproducing unit30shown in the lower part of the figure is separated from the recording unit20, and it includes a line-of-sight detection camera151, a light emitting device152, and a display unit141. The reproducing unit30is a mobile terminal that includes a built-in battery and is portable by a user. The recording unit20and the reproducing unit30are connected by wireless communication. The reproducing unit30shown in the figure is in the state of displaying event recording data C1on the display unit141. Note that, as shown therein, in addition to the video of the event recording data, the date and time of the occurrence of an event, the latitude and longitude, the traveling speed and the like may be displayed on the display unit141.

The configuration of the recording unit20is described hereinafter with reference toFIG. 10.FIG. 10is a block diagram showing the configuration of the recording unit according to the modified example of the first embodiment. The recording unit20includes, as main elements, a control unit200, and a camera150, a recording device160, an operation unit240, an acceleration sensor142, a GPS receiving unit143, and a communication unit270, which are connected to the control unit200. Further, the control unit200includes a captured data acquisition unit120, a buffer memory121, a captured data processing unit122, a recording control unit123, a reproduction control unit124, an operation control unit225, an event detection unit127, a location information acquisition unit128, a timer129, and a communication control unit232, which are connected to the bus line110. In the above-described elements, the elements having the same function as the elements included in the recording/reproducing device10according to the first embodiment are denoted by the same reference symbols. The description of the elements denoted by the same reference symbols is omitted as appropriate, and the elements denoted by new reference symbols are described hereinbelow.

The operation unit240is a user interface for receiving a user's operation on the recording unit20. The user interface may be an operation button or a touch sensor, for example. Further, the user interface may be a receiving unit of infrared rays or radio communication, and it may receive a signal transmitted from a remote control or the like. The operation unit240may be an interface that receives an instruction for a specified operation from the reproducing unit30through the communication unit270. The operation unit240supplies operation information, which is information about a received operation, to the operation control unit225through a specified interface. The operation information is an instruction for starting event recording, for example.

The communication unit270is an interface that is connected for communication with the reproducing unit30, and it is composed of an antenna and a circuit that modulates or demodulates a signal transmitted through the antenna and the like, for example. The communication unit270receives a signal from the reproducing unit30and transmits event recording data to the reproducing unit30.

The operation control unit225acquires operation information received by the operation unit240, and outputs an operation instruction based on the operation information to each component. The communication control unit232controls communication with the reproducing unit30performed through the communication unit270. For example, when the communication control unit232receives a signal that requests reproduction of event recording data from the reproducing unit30, it supplies this request signal to the reproduction control unit124. Further, when the reproduction control unit124outputs event recording data in response to a request from the reproducing unit30, the communication control unit232transmits this event recording data to the reproducing unit30through the communication unit270.

The reproducing unit30is described hereinafter with reference toFIG. 11.FIG. 11is a block diagram showing the configuration of the reproducing device according to the modified example of the first embodiment. The reproducing unit30includes, as main elements, a control unit300, and a display unit141, a line-of-sight detection camera151, a light emitting device152, an operation unit340, and a communication unit370, which are connected to the control unit300. Further, the control unit300includes a captured data acquisition unit120, a light emission control unit131, a display control unit126, a line-of-sight detection unit130, a buffer memory321, a communication control unit332, and an communication control unit332, which are connected to a bus line310.

The communication unit370is an interface that is connected for communication with the recording unit20, and it has the same configuration as the communication unit270included in the recording unit20, for example. The communication unit370transmits a signal that requests event recording data to the recording unit20, and also receives event recording data from the recording unit20and supplies the received event recording data to the communication control unit332.

The operation control unit325acquires operation information received by the operation unit340, and outputs an operation instruction based on the operation information to each component. The communication control unit332controls communication with the recording unit20performed through the communication unit370. For example, the communication control unit332transmits a signal that requests reproduction of event recording data to the reproducing unit30through the communication unit370. Further, the communication control unit332supplies event recording data received through the communication unit370to the buffer memory321.

The operation unit340is a user interface for receiving a user's operation on the reproducing unit30. The user interface may be an operation button or a touch sensor placed on the display unit141, for example. The operation unit340supplies operation information, which is information about a received operation, to the operation control unit325through a specified interface. The operation information is an instruction for starting the reproduction of event recording data or an instruction for ending the reproduction of event recording data being reproduced, for example.

The buffer memory321is a volatile memory. The buffer memory321temporarily stores event recording data transmitted from the recording unit20, and supplies the stored event recording data to the display control unit126.

Note that the above-described reproducing unit30may be implemented by a smartphone or tablet having a wireless communication function. In the case of using a smartphone as the reproducing unit30, the function of the reproducing unit30may be exerted by installing an application program for reproducing event recording data into this smartphone and executing the installed application program, for example.

A modified example of the first embodiment is described above. When a specified event occurs, the recording/reproducing device10according to the modified example of the first embodiment records event recording data into the recording device160in the recording unit20. When the line-of-sight detection unit130in the reproducing unit30detects that a user's line of sight is pointing towards a display unit41before the period PX is reached after the occurrence of the event, it displays event recording data on the display unit141. This structure allows a user who uses the recording/reproducing device10according to the modified example of the first embodiment to visually check the event recording data of the event that has occurred most recently by looking at the reproducing unit30at hand. Therefore, according to the modified example of the first embodiment, there are provided a recording/reproducing device and the like that reproduce stored data without a complicated operation in an optimum manner at a position easily viewable to a user.

Second Embodiment

A second embodiment is described hereinafter. In a recording/reproducing device according to the second embodiment, the function of the line-of-sight detection unit130is different from that of the first embodiment in the process of reproducing event recording data. In the recording/reproducing device10according to the second embodiment, the line-of-sight detection unit130detects the position of user's both eyes from captured data acquired from the line-of-sight detection camera151, and measures the distance between the detected both eyes.

FIG. 12is a view showing an example of captured data acquired by the line-of-sight detection camera151according to the second embodiment. A video image D1shown in the figure is an image of video data acquired by the line-of-sight detection camera151. In the video image D1, a user U1is shown on the left and a user U2is shown on the right, when viewed from the front. The face of the user U1is closer to the line-of-sight detection camera151than the face of the user U2is. The line-of-sight detection unit130recognizes the face and eyes of a person from pixel values contained in the captured data, and calculates the distance between two eyes contained in the recognized face on the captured data. For example, a distance B1between both eyes of the user U1is greater than a distance B2between both eyes of the user U2. In this manner, a user's face captured by the line-of-sight detection camera151tends to be farther as the distance between both eyes is shorter, and a user's face tends to be closer as the distance between both eyes is longer. The line-of-sight detection unit130determines whether a value corresponding to the distance between both eyes of a user is greater than a predetermined threshold Bth or not. The recording/reproducing device10is configured to start the reproduction of event recording data when the distance between both eyes is greater than the threshold Bth. Specifically, the reproduction control unit124calculates the distance between both eyes of a user, and when the calculated value is greater than a predetermined threshold, starts reproducing event recording data. The threshold Bth is set to a value when a user's face is as close as about 50 cm to the display surface of the display unit141on the basis of the average width of both eyes, for example.

A process of the recording/reproducing device according to the second embodiment is described hereinafter with reference toFIG. 13.FIG. 13is a flowchart in the case where the recording/reproducing device according to the second embodiment reproduces event recording data. The flowchart according to the second embodiment is different from the process according to the first embodiment in that Step S120is inserted between Steps S113and S114. The same points as in the flowchart of the first embodiment are not redundantly described below, and different points from the first embodiment are described.

In Step S113, when it is determined that a user's line of sight is pointing towards the display unit141in Step S113(Step S113: Yes), the reproduction control unit124determines whether a distance BX between both eyes of the user is greater than the threshold Bth (Step S120). When it is not determined that the distance BX is greater than the threshold Bth (Step S120: No), the control unit100proceeds to Step S112. On the other hand, when it is determined that the distance BX is greater than the threshold Bth (Step S120: Yes), the reproduction control unit124proceeds to Step S114.

The second embodiment is described above. In the above configuration, when a user's line of sight is pointing towards the display unit141before the predetermined period PX has elapsed after the occurrence of a specified event and when the user's face is not away from the display unit141, the recording/reproducing device10according to the second embodiment reproduces the most recent event recording data. This allows a user to check the event recording data by coming closer to the display unit of the recording/reproducing device and looking at the display unit immediately after the occurrence of an event such as an accident, for example. Therefore, according to the second embodiment, there are provided a recording/reproducing device and the like that reproduce stored data without a complicated operation.

The above-described program can be stored and provided to the computer using any type of non-transitory computer readable medium. The non-transitory computer readable medium includes any type of tangible storage medium. Examples of the non-transitory computer readable medium include magnetic storage media (such as floppy disks, magnetic tapes, hard disk drives, etc.), optical magnetic storage media (e.g. magneto-optical disks), CD-ROM (Read Only Memory), CD-R, CD-R/W, and semiconductor memories (such as mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (Random Access Memory), etc.). The program may be provided to a computer using any type of transitory computer readable medium. Examples of the transitory computer readable medium include electric signals, optical signals, and electromagnetic waves. The transitory computer readable medium can provide the program to a computer via a wired communication line such as an electric wire or optical fiber or a wireless communication line.

The present embodiment is not restricted to the above-described embodiments, and various changes and modifications may be made without departing from the scope of the invention. For example, although the above-described recording/reproducing device is described as an example of a dashboard camera that is mounted on an automobile, the recording/reproducing device may be mounted on different types of vehicles such as a motorcycle and a bicycle. Further, the recording/reproducing device is not necessarily mounted on a vehicle, and it may be mounted on movable objects such as a railroad car, a ship and an aircraft. Further, the recording/reproducing device may be worn by human, a walking robot, or the like.

The present application is applicable to a recording/reproducing device that is mounted on a vehicle and records and reproduces a video.