JP2014154995A - Visual recognition device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display a subject image equivalent to an image viewed through the mirror of a vehicle on a display even when the same on-vehicle camera is attached to the vehicle differing in vehicle model.SOLUTION: An on-vehicle camera 8 includes: an imaging optical system 9 for imaging a subject; an imaging element 10 for forming a subject image G1 by the imaging optical system 9; a signal processing circuit 11 for digitizing the subject image G1 formed in the imaging element 10 and generating an image G2' corresponding to the aspect ratio of a screen GA; and a digital/analog signal conversion circuit 12 for converting the image G2' generated by the signal processing circuit 11 into an NTSC image signal and outputting the signal to a display 7. The signal processing circuit 11 has a selectable rectangular frame for segmentation corresponding to the area of a posterior visual field to be viewed through an on-vehicle mirror and also a posterior visual field having a different horizontal angle for each vehicle model.

Description

  The present invention relates to an improvement of a vehicular visual recognition device.

  Conventionally, a vehicular visual recognition device has an aspect ratio corresponding to an aspect ratio of a horizontal width and a vertical width of an in-vehicle mirror. The thing of the structure displayed on vehicle-mounted displays, such as a liquid crystal display device, is known (for example, refer patent document 1).

Japanese Utility Model Publication No. 03-28947

    By the way, the aspect ratio between the horizontal width and the vertical width of the subject image photographed by the in-vehicle camera and the aspect ratio between the horizontal width and the vertical width of the in-vehicle display are, for example, the aspect ratio of the subject image is 4: 3. On the other hand, the aspect ratio of the display screen is 4: 1, and the aspect ratio of the subject image is different from the aspect ratio of the display screen.

    In view of this, a vehicular visual recognition device is being developed that cuts out a subject image from the subject image using a rectangular frame corresponding to the aspect ratio of the display, creates a cut-out image, and displays the cut-out image on the display as the subject image.

    However, as shown in FIG. 1, in the vehicle 1 and the vehicle 2 having different vehicle types, as shown in FIG. 1 (A) and FIG. 1 (B), the rear side seen through the window by the same in-vehicle mirror 3 The horizontal angles H1 and H2 of the field of view may be different.

    Therefore, as shown in FIG. 2, the subject area G1 seen through the mirror 3 of the vehicle 1 and the subject area G2 seen through the mirror 3 of the vehicle 2 are different for a subject existing at the same distance from the vehicle body.

For this reason, when the subject image is cut out by the same rectangular frame and displayed on the display, depending on the vehicle model, the rear view seen through the mirror 3 and the subject image seen through the display built in the mirror 3 are seen. Is not desirable from the standpoint of complying with laws and regulations.

    The present invention has been made in view of the above circumstances, and even when the same in-vehicle camera is attached to a vehicle of a different vehicle type, a subject image equivalent to the view seen through the mirror of the vehicle is incorporated in the mirror. An object of the present invention is to provide a vehicular visual recognition device that can be displayed on a display.

The present invention provides a vehicular visual device for displaying a subject image captured by a vehicle-mounted camera on a vehicle-mounted display having a screen having an aspect ratio different from the aspect ratio of the subject image. The vehicle-mounted camera includes: A photographing optical system for photographing a subject, an imaging element on which a subject image is formed by the photographing optical system, and a subject image formed on the imaging element is digitized and cut out with an aspect ratio corresponding to the aspect ratio of the screen An image cutout circuit that creates a cutout image, and a digital / analog signal conversion circuit that converts the cutout image created by the image cutout circuit into a video signal that matches the input form of the display and outputs the video signal to the display, The image cut-out circuit is a rear view that can be seen through a vehicle-mounted mirror, and depends on the vehicle type. And having a square frame for excision of selected depending the clipped image is horizontally angle corresponding to the regions of different rear view in models Te.

    According to the present invention, it is possible to select a cut-out image corresponding to a rear view field that is visible through a vehicle-mounted mirror and has a different horizontal angle depending on the vehicle type according to the vehicle type. Even when the is attached to a vehicle of a different vehicle type, it is possible to display on the display a subject image equivalent to the view seen through the mirror of the vehicle.

FIG. 1 is an explanatory diagram for explaining that the horizontal angle of the rear view seen through the mirror differs depending on the vehicle type. FIG. 2 is an explanatory diagram showing an example of the rear view. FIG. 3 is an explanatory diagram showing an example of a vehicle equipped with the vehicle-mounted camera according to the present invention. FIG. 4 is a block circuit diagram of the vehicle visual recognition device according to the present invention. FIG. 5 is an explanatory diagram showing an example of a subject image captured by the in-vehicle camera shown in FIG. FIG. 6 is an explanatory diagram of the display shown in FIG. FIG. 7 is an explanatory diagram showing an example of a cut-out image cut out by the rectangular frame shown in FIG. FIG. 8 is an explanatory diagram showing an example of an expanded image expanded by the image expansion circuit shown in FIG. FIG. 9 is an explanatory diagram of the cut-out image displayed on the display shown in FIG. FIG. 10 is an explanatory diagram showing a problem when a cutout image is converted into a video signal without being expanded.

    FIG. 3 is a plan view showing a state in which a vehicle equipped with the vehicle visual recognition device according to the present invention is viewed from above. In FIG. 3, reference numerals 5 and 6 denote vehicles having different vehicle types, 7 denotes a display as a vehicle-mounted mirror (a display built in the vehicle-mounted mirror), and 8 denotes a vehicle-mounted camera.

    The in-vehicle camera 8 is provided on the roofs of the vehicles 5 and 6, and has the same shooting angle of view H in the horizontal direction of a subject located at an equal distance from the display 7. That is, the vehicle-mounted camera 8 mounted on the vehicle 5 and the vehicle 6 is the same model.

    In addition, in FIG. 3, the codes | symbols H1 and H2 have each shown the horizontal direction angles H1 and H2 of the rear view which can be seen through a window, when a vehicle-mounted display is functioned as a mirror.

    As shown in FIG. 4, the in-vehicle camera 8 is roughly composed of a photographing optical system 9, an image pickup device 10 such as a CMOS and a CCD, a signal processing circuit 11, and a digital / analog signal conversion circuit 12. A subject image G 1 shown in FIG. 5 is formed on the image sensor 10 through the photographing optical system 9.

    The aspect ratio between the horizontal width H3 and the vertical width V3 of the subject image G1 is 4: 3. On the other hand, as shown in FIG. 6, the aspect ratio of the horizontal width H3 and the vertical width V3 of the screen GA of the display 7 is 4: 1.

    The subject image G1 formed on the image sensor 10 is digitized by the signal processing circuit 11 shown in FIG. 4 and stored as a digital image in a frame memory (buffer memory) (not shown), for example.

    The signal processing circuit 11 includes an image cutout circuit 11a and an image decompression circuit 11b. The image cutout circuit 11a cuts out an image having a horizontal width H3 and a vertical width V3 of 4: 1 from the subject image G1 using the rectangular frames FR1 and FR2 shown in FIG. 5, and cuts out the images as shown in FIGS. It has a role of creating images G1 ′ and G2 ′, respectively.

    The rectangular frames FR1 and FR2 are stored in the image cutout circuit 11a, for example. The rectangular frames FR1 and FR2 are selected by a camera control signal from an electronic control unit (ECU) 13 mounted on the vehicles 5 and 6, for example.

    Here, the rectangular frames FR1 and FR2 are selected by the electronic control unit (ECU) 13. However, the present invention is not limited to this, and for example, the in-vehicle camera 8 is provided with a selection switch for the rectangular frames FR1 and FR2. It can also be set as the structure provided.

    Image data composed of the cut-out images G1 'and G2' having an aspect ratio of 4: 1 is input to the image expansion circuit 11b. The image decompression circuit 11b decompresses the cut-out images G1 ′ and G2 ′ shown in FIGS. 7A and 7B to create a decompressed image G1 ″ having an aspect ratio of 4: 3 between the horizontal width H3 and the vertical width V3. Have a role to play.

    FIG. 8 shows an expanded image G1 ″ obtained by extending the cutout image G1 ′ and extending in the vertical direction. That is, the image expansion circuit 11b uses the same image data corresponding to one line in the horizontal direction. Three lines of image data are created, whereby a decompressed image G1 ″ shown in FIG. 8 is created.

    The image data composed of the expanded image G1 ″ is input to the digital / analog signal conversion circuit 12. The digital / analog signal conversion circuit 12 converts the expanded image G1 ″ into a video signal of the NTSC system (interlace system). Output to the display 7.

    Thereby, when the vehicle-mounted camera 8 is mounted on the vehicle 5, the rectangular frame FR1 shown in FIG. 5 is selected, and the cutout image G1 corresponding to the horizontal angle H1 of the rear view of the vehicle 5 shown in FIG. 'Is displayed on the screen GA of the display 7 as shown in FIG.

    Further, when the in-vehicle camera 8 is mounted on the vehicle 6, the rectangular frame FR2 shown in FIG. 5 is selected, and the cutout image G2 ′ corresponding to the horizontal angle H2 of the rear view of the vehicle 6 shown in FIG. Is displayed on the screen GA of the display 7 as shown in FIG.

    In this embodiment, the two types of cutout rectangular frames FR1 and FR2 are prepared. However, the present invention is not limited to this, and a cutout rectangular frame is provided for each vehicle type having different horizontal angles of the rear view. A configuration in which a plurality of pieces are prepared in advance can also be adopted.

    According to this embodiment, the in-vehicle camera 8 is provided with an image clipping circuit 11a, and a plurality of rectangular frames for clipping are prepared in the image clipping circuit 11a for each vehicle type having different horizontal angles of the rear view, Since it is possible to select a cut-out image corresponding to the rear view area that is visible through the in-vehicle mirror and has a different horizontal angle depending on the vehicle type, it is necessary to prepare an in-vehicle camera for each vehicle type Therefore, there is an effect that it is possible to prepare an in-vehicle camera of a unified standard and create a cut-out image required for the vehicle type according to the vehicle type.

    In this embodiment, the cutout images G1 ′ and G2 ′ cut out by the rectangular frames FR1 and FR2 are extended in the vertical direction by the image extension circuit 11b to create the extended image G1 ″. The reason is as follows.

    As described above, the aspect ratio of the subject image G1 photographed by the in-vehicle camera 7 is 4: 3, whereas the aspect ratio of the cutout images G1 ′ and G2 ′ cut out by the rectangular frames FR1 and FR2 is as follows. 4: 1.

    When the image data composed of the cut-out images G1 ′ and G2 ′ is converted into an NTSC video signal (video signal adapted to the input form of the display) by the digital / analog signal conversion circuit 12 and output to the display 7, the NTSC video signal is output. Since the number of scanning lines is 525 and there is no image data of the cut subject image, the subject image G ′ having a black region GB at the top and bottom and compressed in the vertical direction, that is, as shown in FIG. The subject image G ′ is distorted in the direction.

    On the other hand, according to this embodiment, after the decompression image having the aspect ratio corresponding to the aspect ratio of the subject image G1 is created by the image decompression circuit 11b, the image data composed of the decompression image G1 ″ is converted into a video signal. Therefore, the cut-out images G1 and G2 having no distortion are displayed corresponding to the aspect ratio of the display 7 having an aspect ratio different from that of the subject image G captured by the in-vehicle camera 8. 7 can be displayed.

5, 6 ... Vehicle 7 ... Display 8 ... In-vehicle camera 11a ... Image clipping circuit 11b ... Image decompression circuit 12 ... Digital / analog signal conversion circuit G1 ... Subject image GA ... Screens H1, H2 ... Rectangular frames FR1, FR2 ... Rectangular frames G1 ', G2' ... clipped image

Claims (4)

In a vehicular visual recognition device that displays a subject image captured by a vehicle-mounted camera on a vehicle-mounted display having a screen with an aspect ratio different from the aspect ratio of the subject image,
The in-vehicle camera has a photographing optical system for photographing a subject, an image sensor on which a subject image is formed by the photographing optical system, and digitizes the subject image formed on the image sensor to correspond to the aspect ratio of the screen An image clipping circuit that creates a clipped image by clipping with an aspect ratio, and a digital / analog signal conversion that converts the clipped image created by the image clipping circuit into a video signal that matches the input form of the display and outputs the video signal to the display With circuit,
The image cut-out circuit has a cut-out rectangular frame that allows selection of a cut-out image corresponding to a rear view area that is visible through an in-vehicle mirror and has a different horizontal angle depending on the vehicle type, depending on the vehicle type. A vehicular visual recognition device.     The vehicular visual recognition device according to claim 1, wherein the image cut-out circuit selects the cut-out rectangular frame by a control signal from an electronic control unit of a vehicle on which the vehicle-mounted camera is mounted.     An image decompression circuit configured to decompress the cropped image and create an decompressed image having an aspect ratio corresponding to an aspect ratio of the subject image between the image cropping circuit and the digital / analog signal conversion circuit; 3. The vehicular visual recognition device according to claim 1, wherein the analog signal conversion circuit converts the expanded image into an NTSC video signal and outputs the video signal to the display.     The vehicular visual recognition device according to claim 3, wherein the image expansion circuit expands the clipped image in a vertical direction.