JP2006127206A - Image recording apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To record image data from just before an accident up to just after the accident at the occurrence of a collision accident or the like of an automobile. <P>SOLUTION: An image recording apparatus is constituted of: an image pickup camera 1 for photographing the outside of the automobile; a collision sensing sensor 2 for sensing shock or the like; an image buffering part 3 for temporarily storing image data; an image compression part 4 for performing the compression processing of the image data; an image recording part 5 for recording the compressed image data, a power supply part for receiving power supply from a car battery 7; and a secondary feeding device built in the power supply part. Until reception of a signal from the shock sensing sensor 2, only the image buffering part 3 is driven to attain low-consumption driving, and since the secondary feeding device 6 is arranged, the drive of the apparatus is not hindered by the stop of power supply from the car battery 7. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image recording apparatus capable of recording image data immediately before a collision in a traffic accident or the like, and image data after the collision, for the purpose of image recording before and after the generation of an impact detection signal, and more particularly to the generation of an impact detection signal. The present invention relates to an image recording apparatus that takes into account efficient apparatus operation before and after.

Various proposals and inventions have been made so-called drive recorders for analyzing the cause of a traffic accident using an image after the accident has occurred.
These are described in, for example, JP-A-5-197858 (driving recorder), JP-A-9-198858 (vehicle-mounted image recording apparatus), JP-A-10-210395 (image recording apparatus), and the like.
JP-A-5-197858 JP-A-9-198858 Japanese Patent Laid-Open No. 10-210395

  The first problem is the problem of recording capacity. When trying to analyze the cause of an instantaneous event such as a traffic accident using images, it is most important that the image is clear and that the frequency of images per unit time is sufficient, and that an accident occurs. If it is attempted to record not only the previous situation but also the situation after the occurrence, the amount of data required for recording and storage becomes considerably large.

  As an example, when recording 10 seconds (total 20 seconds) before and after the accident in RGB (24 bits) format with resolution VGA (640 dots × 480 dots) at a frequency of 30 frames / second, 550 A recording capacity of megabytes or more is required. When such a capacity is mounted on a device using a nonvolatile memory such as a Flash-ROM, an increase in the size of the device and a significant price increase are inevitable.

   The second problem is a power supply problem. In-vehicle image recording devices normally operate with power supplied from a car battery. However, when a traffic accident occurs, recording after the accident has occurred even if power supply is stopped and the device itself is not damaged. May not be possible. Moreover, since the car battery itself is not a very powerful power source, it is essential to reduce the power consumption of the device during normal operation.

  In the present invention, in order to solve the first problem, image compression means such as JPEG or MPEG encoder is provided in the apparatus. As an example, when JPEG compression is performed, the data capacity of 550 megabytes can be compressed to about 30 to 40 megabytes with almost no deterioration in image sharpness. However, when the compression means as described above is provided, the compression processing circuit itself has power consumption in addition to the normal image storage, so that the normal method acts rather negatively on the second problem. . Therefore, in the present invention, in order to solve the second problem at the same time as the first problem, one or more of the following means are used.

  (1) In the apparatus, there is provided an image compression means, a nonvolatile memory medium such as a Flash-ROM for writing compressed data, and a writing means for the medium, and a buffer circuit constituted by an SD-RAM or the like Until the signal from the impact sensor is received, overwriting of the image data for a desired time is repeated in the buffer circuit. Further, at this time, the image compression means and the medium writing means are stopped or put into a power saving standby state to suppress the power consumption of the entire apparatus.

  (2) A signal from the impact sensor is received, overwriting to the buffer circuit is stopped after a desired time elapses, the image compression means and the writing means are activated, and the data stored in the buffer circuit is sequentially compressed. And writing onto a non-volatile memory medium. At this time, it is desirable that the compression processing time is as short as possible. However, since the image data to be processed already exists in the buffer, it goes without saying that there is no problem even if the compression is performed slowly in accordance with the performance of the compression processing means.

  (3) In preparation for the case where the power supply from the car battery is stopped due to a collision or the like, a reserve power supply is provided inside the apparatus in order to secure power for performing the process (2). The process (2) may always be performed using the standby power supply regardless of the external power supply, or may be performed using the standby power supply only when the power supply is stopped.

  In the present invention, since any one of the above means (1) and (2) or a plurality of means can be used, low power consumption driving is possible, so that the load on the car battery used as a power source can be reduced. By providing a secondary power supply device as a standby power source in this device, image compression is applied to the image data for the desired time (from the time immediately before the accident to a certain time after the accident) regardless of the power supplied from the car battery. It is possible to reliably complete the processing operations of the image compression unit serving as the means and the image recording unit serving as the image writing means.

  A block diagram of the present invention for enabling the above functions is shown in FIGS.

  FIG. 1 shows a block diagram of a first embodiment of the present invention. An image recording apparatus according to the present invention includes an imaging camera 1 for shooting outside a vehicle, an impact detection sensor 2 that detects an impact and outputs a signal, and temporarily holds image data output from the imaging camera 1. An image buffering unit 3, an image compression unit 4 for performing data compression processing on the image data, an image recording unit 5 for recording the compressed image data, and a microcomputer for controlling or managing each processing unit (CPU) 8 and a car battery 7 as power supply from the outside of the apparatus.

  The imaging camera 1 is an imaging device that can capture image data in any shooting scene such as daytime, nighttime, and bad weather, such as a MOS imaging device or a CCD camera. The installation position of the imaging camera 1 should be consistent with the installation position of the impact detection sensor 2 to be described later, considering that it is a camera for capturing images outside the vehicle in the direction of impact generation, which is necessary information. Installed at a position where a video outside the vehicle in the direction of the collision can be taken. The impact detection sensor 2 outputs an impact detection signal by detecting an impact or a sudden speed change, and the installation position thereof corresponds to the impact from any direction on the vehicle. Install on the side.

The image recording apparatus according to the present invention is in a normal processing state until the microcomputer 8 built in the apparatus receives a signal from the impact detection sensor 2 that outputs an impact detection signal by detecting an impact or a rapid speed change. In this normal processing state, the image buffering unit 3 constituted by an SD-RAM or the like is always operated in order to temporarily hold the image data output from the imaging camera 1. The image buffering unit 3 repeats the process of sequentially overwriting the image data for the desired time and replacing the old image data with new image data. Therefore, the image buffering unit 3 does not need to secure an unnecessarily large memory capacity, and a buffering circuit can be configured with an SD-RAM having a minimum memory capacity necessary for image buffering.

  In the state shown above, until the microcomputer 8 built in the apparatus receives a collision detection signal from the impact detection sensor 2, that is, in the normal processing state, an image compression unit which is an image compression unit. 4 and the image recording unit 5 that records and stores the compressed image data are configured to be able to suppress drive power consumption in the normal processing state of the apparatus by stopping or waiting in a power saving state.

  When the microcomputer 8 built in the apparatus shown above receives a collision detection signal from the impact detection sensor 2, the image buffering unit 3 stores the image data after receiving the signal for a desired time. Temporarily save the image without stopping the image data overwrite process. When the desired time elapses from the time when the microcomputer 8 built in the apparatus receives the collision detection signal from the impact detection sensor 2, the image buffering unit 3 stores the image data in accordance with a command from the microcomputer 8 built in the apparatus. The buffering means that is a temporary holding process is stopped.

  After stopping the temporary holding process of the image data in the image buffering unit 3 described above, the image data temporarily held in the image buffering unit 3 is several tens before and after the collision, which is a required time. The storage position of the image data corresponding to the second is determined, and the determined compression processing for the required image data is sequentially performed in the image compression unit 4 provided with image compression means such as JPEG or MPEG encoder. The image compression unit 4 is handled by processing by a soft encoder or a DSP with a built-in microcomputer.

  The image data compressed by the image compression unit 4 shown above is stored in the image recording unit 5 which can be connected to a CF card which is a nonvolatile memory medium such as a flash ROM or various recording media such as a memory stick. It is recorded as compressed image data in a recording medium. At this time, the memory capacity of the recording medium is sufficient to record the compressed image data of the video outside the vehicle in the direction of impact for several tens of seconds before and after the collision detection signal is generated.

  FIG. 2 shows a block diagram of the second embodiment of the present invention. 2 is different from FIG. 1 in that a block diagram relating to a power supply unit of the image recording apparatus according to the present invention is shown, and a secondary power supply device 6 serving as a standby power supply is provided in the apparatus. In the image recording apparatus according to the present invention, during the buffering process for temporarily storing the image data in the image buffering unit 3 in the normal processing state as shown in the first embodiment, the car battery 7 mounted on the vehicle as a power source is used. Receive the power.

  However, in the event of a collision with the vehicle, the car battery 7 itself is damaged, or an unexpected situation such as disconnection of the power supply wiring from the car battery 7 to the apparatus occurs. In order to prevent this apparatus from stopping when the supply is interrupted or when the power supply voltage from the car battery 7 to this apparatus is lowered for some reason, the secondary power supply apparatus 6 as a standby power supply apparatus is It is provided in the apparatus. As a power storage means of the secondary power feeding device 6 as the standby power source, a large-capacity capacitor is provided in the device.

The microcomputer 8 built in the apparatus always monitors the power supply voltage supplied from the car battery 7 and may hinder the processing operation of the apparatus, such as a decrease in the power supply voltage from the car battery 7. When it is sensed that there is a risk that the system will be in a negative state, the power supply to this apparatus is not supplied from the car battery 7 but from the secondary power supply apparatus 6 which is a standby power supply provided in this apparatus. Switch to feeding.
By using the power supply switching means from the standby power supply as described above, it is possible to compress the necessary image data over several tens of seconds after the collision detection and to the memory medium as a recording medium, as shown in the first embodiment. Therefore, the processing is not stopped in the middle of the recording and storing process of the compressed image data, and the image data outside the vehicle before and after the required collision can be stored in the recording medium for the desired time in the form of the compressed image data.

  In this apparatus that enables the series of processing operations shown in the first embodiment and the second embodiment, the image data stored in the recording medium can be used as an important information record as objective evidence in accident verification and the like later. It is possible.

1 is a block diagram illustrating an image recording apparatus according to a first embodiment of the present invention. The block diagram which shows the image recording device of the 2nd Example of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Imaging camera 2 ... Impact detection sensor 3 ... Image buffering part 4 ... Image compression part 5 ... Image recording part 6 ... Secondary electric power feeder (UPS)
7 ... Car battery on board 8 ... Microcomputer (CPU)

Claims (2)

  An imaging camera unit or an image signal input unit, a sensor unit that detects an impact or a sudden speed change and outputs an impact detection signal, and an image buffer circuit that temporarily stores a video signal from the imaging camera unit or the image signal input unit An image buffering unit having an image buffering unit, an image compression unit for data compression processing of a video signal stored in the image buffering unit, an image recording unit for storing data from the image compression unit in a nonvolatile semiconductor memory, and each unit of the device In an image recording apparatus for recording images before and after the generation of the impact detection signal, comprising an electric power supply apparatus that supplies a desired voltage, the image compression is performed during a period from when power supply to the apparatus is started until the generation of the impact detection signal. Either the image recording unit or the image recording unit, or both of them are set to a standby state that is in a stopped state or a power saving state, and when the impact detection signal is generated, the image compression unit and the image recording unit Image recording apparatus is characterized by providing a means allowed to start the operation of the recording unit.   2. The image recording apparatus according to claim 1, wherein a secondary power feeding device having power storage means is provided, and during operation, a power supply voltage from a car battery, which is power fed from outside the device, is constantly monitored by a microcomputer built in the image recording device. However, when a phenomenon such as a drop in power supply voltage or disconnection occurs, there is provided means for switching the device power supply to the secondary power supply device provided in the device instead of the conventional car battery power supply and operating the device. An image recording apparatus.

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