JP2012218505A - Display device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a display device for a vehicle capable of accurately superimposing an enhanced image on the image of a detection target while maintaining a simple configuration.SOLUTION: A display device 100 for a vehicle detects a pedestrian image 70 from frontal images 50 sequentially created by a near-IR camera 10 that photographs the frontal region 90 of the vehicle, and sequentially displays images by superimposing the frontal region 90 on the frontal images 50. The display device 100 for a vehicle sequentially acquires frontal images 50 by an image acquiring unit 21 from the near-IR camera 10, and extracts positional information and size information of the pedestrian image 70 from the frontal images 50 by a pedestrian detecting unit 23. According as the traveling speed of the vehicle acquired by a speed information acquiring unit 25 is increased, the size of an enhanced image 60 is enlarged with respect to a reference size corresponding to the size information. The enhanced image 60 enlarged and drawn is superimposed at a position CP corresponding to the positional information in the current frontal image 50n.

Description

  The present invention relates to a vehicle display device that displays a front image obtained by photographing a front area of a vehicle.

  Conventionally, in order to easily show the detection target existing in the front area of the vehicle to the viewer, an emphasized image that emphasizes the image of the detection target is superimposed on the front image obtained by photographing the front area, for example, A vehicle display device as disclosed in Patent Document 1 and Patent Document 2 is known.

  The vehicle display device disclosed in Patent Literature 1 includes an infrared night-vision camera that captures a front region, and a specific image extraction unit that calculates position coordinates in a front image of an image of a person or the like. The vehicular display device of Patent Document 1 pastes a mark as an emphasized image at a coordinate position calculated from a previous front image by a specific image extraction unit in a front image currently captured by an infrared night vision camera. Affixed by means and displayed sequentially on the display device.

  The vehicle display device disclosed in Patent Literature 2 includes an imaging device that captures a front region and an image analysis unit that performs an analysis that identifies the position of the image of the detection target. Further, the vehicular display device disclosed in Patent Document 2 is an image buffering that buffers the front image so that the image of the detection target in the front image and the marker image as the emphasized image superimposed on the front image do not shift. Department. The vehicular display device of Patent Literature 2 performs an analysis for specifying the position of the image of the detection target for the front image stored in the image buffering unit by the image analysis unit. Then, the vehicular display device superimposes the marker image on the position of the image of the detection target specified by the image analysis unit in the front image stored in the image buffering unit, and outputs the marker image from the image output unit. As described above, in the vehicle display device disclosed in Patent Document 2, the front image in which the analysis for specifying the position is performed and the front image in which the marker image is superimposed based on the analysis result are the same. Therefore, the shift between the detection target image and the marker image is suppressed.

JP 2000-46521 A JP 2009-255608 A

  Now, in the display apparatus for vehicles of patent document 2, since the image buffering part which buffers a front image is required, the structure of an apparatus becomes complicated. On the other hand, the vehicular display device of Patent Document 1 sequentially displays the current front image captured by the infrared night vision camera, so that the configuration can be simplified compared to the vehicular display device of Patent Document 2. However, in the vehicle display device of Patent Document 1, it is difficult to paste a mark accurately on a person's image. The reason will be described below.

  In the vehicle display device disclosed in Patent Document 1, the vehicle approaches an actual person existing in the front area during the time when the specific image extraction unit calculates the position coordinates of the human image from the front image. Therefore, the human image in the current forward image captured by the infrared night vision camera appears larger in the forward image than the human image in the past forward image whose position coordinates are calculated. Therefore, even if the mark corresponding to the human image in the past front image is pasted on the current front image, it may not be able to accurately correspond to the image of the detection target object such as a human shown in the current front image. It is.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a vehicle display device capable of accurately superimposing an emphasized image on an image of a detection target while maintaining a simple configuration. That is.

  In order to achieve the above object, in the invention described in claim 1, an image of a detection target existing in the front area is detected from a front image sequentially generated by an imaging unit that images the front area of the vehicle. A display device for a vehicle that sequentially displays an emphasized image that enhances an image of the detection target object in a superimposed manner on a front image, the image acquiring unit sequentially acquiring a front image from an imaging unit, and acquired by the image acquiring unit By detecting the image of the detection object from the front image, the object information extracting means for extracting the position information and the size information of the image of the detection object in the front image, and the speed information for acquiring the vehicle speed information The size of the emphasized image corresponding to the size information extracted by the acquisition means and the object information extraction means is set as a reference size, and the running based on the information acquired by the speed information acquisition means The position information extracted by the object information extracting means in the drawing means for drawing the emphasized image greatly enlarged with respect to the reference size as the speed increases, and the current forward image sequentially obtained by the image obtaining means The vehicle display device includes display means for sequentially displaying the emphasized images enlarged and drawn by the drawing means at positions corresponding to the above.

  According to this invention, the drawing unit corresponds to the size information extracted by the object information extracting unit as the vehicle traveling speed acquired by the traveling speed acquiring unit increases in size. Enlarges the reference size. Then, the display means is enlarged and drawn by the drawing means at a position corresponding to the position information extracted by the object information extracting means in the current front image sequentially acquired in time series by the image acquiring means. The highlighted images are superimposed and displayed sequentially.

  In the above processing, during the time when the object information extracting unit detects the image of the detection object from the front image and extracts the position information and the size information, the vehicle is detected as an actual detection object existing in the front area. To approach. Therefore, the image of the detection object in the current front image sequentially acquired by the image acquisition means is larger in the front image than the image of the detection object in the past front image from which the position information and the size information are extracted. It will be reflected. Furthermore, as the traveling speed of the vehicle increases, the image of the detection target object in the current front image is greatly enlarged with respect to the image of the detection target object in the past front image and appears in the front image. As described above, the emphasized image is greatly enlarged as the traveling speed of the vehicle increases, so that the size of the emphasized image becomes the size of the image of the detection object shown in the current front image acquired by the image acquisition unit. Can respond accurately.

  In addition, the display means sequentially displays the current front images sequentially acquired by the image acquisition means. Therefore, complication of the vehicular display device can be avoided. As described above, the display device for a vehicle can emphasize the image of the detection target object by accurately superimposing the emphasized image on the image of the detection target object while maintaining a simple configuration.

  In the second aspect of the invention, the speed information acquisition unit acquires the travel speed information from the position information and the size information acquired by the object information extraction unit, and the position information and the size information. The drawing means increases the emphasized image with respect to the reference size corresponding to the size information associated with the traveling speed information by the speed information acquiring means as the traveling speed increases. It is characterized by being drawn in an enlarged manner.

  According to the present invention, the object information extraction unit acquires the position information and the size information of the image of the detection object, so that the speed information acquisition unit acquires the information on the traveling speed and the position information and the size. The information on the traveling speed is associated with the information. Therefore, the difference between the timing at which the position information and the size information are extracted and the timing at which the vehicle travel speed information is acquired is reduced.

  Here, the ratio of the size of the image of the detection object in the current front image to the size of the image of the detection object in the past front image corresponds to the traveling speed of the vehicle. Therefore, by reducing the difference between the timing at which position information and size information are extracted and the timing at which travel speed information is acquired, the drawing means accurately reflects the travel speed of the vehicle in the enlargement of the emphasized image. Can do. As described above, the drawing unit can draw an emphasized image that accurately corresponds to the size of the detection target image in the current front image. Therefore, the vehicular display device can more accurately superimpose the emphasized image on the image of the detection target object to enhance the image of the detection target object.

  In the invention according to claim 3, the drawing means includes an enlargement ratio setting section that sets an enlargement ratio of the emphasized image that is enlarged with respect to the reference size as the traveling speed of the vehicle increases, and an enlargement ratio setting section. And a drawing unit that draws an emphasized image at a drawing size calculated by multiplying a set enlargement ratio by a reference size.

  In this invention, as the traveling speed of the vehicle increases, the enlargement ratio of the emphasized image that is enlarged with respect to the reference size is set larger by the enlargement ratio setting unit. Then, the drawing size of the emphasized image drawn by the drawing unit is calculated by multiplying the reference size by the enlargement rate set by the enlargement rate setting unit. In the above embodiment, the drawing size of the emphasized image surely increases as the traveling speed of the vehicle increases, and thus can correspond to the size of the image of the detection target in the current front image. Therefore, the vehicular display device can more accurately superimpose the emphasized image on the image of the detection target object to enhance the image of the detection target object.

  In the invention according to claim 4, the drawing means follows the horizontal direction when the position of the image of the detection target image in the position information in the front image is in a region on the right side of the center of the front image in the horizontal direction. If the emphasized image is enlarged and drawn in the right direction of the front image and the position of the image of the detection target image in the position information in the front image is in a region on the left side of the center of the front image in the horizontal direction, The emphasis image is enlarged and drawn in the left direction of the front image along the direction.

  In the present invention, when the image of the detection target object is reflected in the region on the right side of the center of the front image in the horizontal direction, the image of the detection target object is caused by the approach of the actual detection target object existing in the front region and the vehicle. It increases while moving to the right of the front image along the horizontal direction. Therefore, the emphasized image is drawn enlarged by the drawing unit in the right direction of the front image, and superimposed on the position corresponding to the position information extracted from the past front image by the display unit. It is possible to accurately correspond to the position and size of the image of the detection object in FIG.

  Similarly, when an image of the detection target object is displayed in a region on the left side of the center of the front image in the horizontal direction, the image of the detection target object becomes horizontal due to the approach between the actual detection target object existing in the front region and the vehicle. The image becomes larger while moving to the left of the front image along the direction. Therefore, the emphasized image is drawn enlarged by the drawing means in the left direction of the front image, and superimposed on the position corresponding to the position information extracted from the previous front image by the display means. It is possible to accurately correspond to the position and size of the image of the detection object in FIG.

  Accordingly, the vehicular display device can more accurately superimpose the emphasized image on the image of the detection target object to enhance the image of the detection target object.

  The invention according to claim 5 is characterized in that the drawing means draws an enhanced image having a shape surrounding an image of the detection target.

  As in the present invention, the enhanced image having a shape surrounding the detection object image can surely enhance the detection object image, while the size of the enhanced image does not correspond to the size of the detection object image. In this case, it overlaps with the image of the detection object, making it difficult to see the image of the detection object. However, as described above, the drawing size of the emphasized image by the drawing unit that enlarges and draws the emphasized image based on the traveling speed of the vehicle is the same as the size of the image of the detection target in the front image displayed by the display unit. It is possible to respond appropriately. Therefore, even if the enhanced image has a shape surrounding the image of the detection target object, a situation in which it is difficult to see the image of the detection target object is avoided, and the effect of enhancing the image of the detection target object is reliably exhibited. Become so. Therefore, the vehicular display device that superimposes the emphasized image of the shape surrounding the image of the detection object on the front image can further enhance the image of the detection object by enlarging the emphasized image according to the traveling speed. .

1 is a configuration diagram schematically illustrating a configuration of a night view apparatus according to an embodiment of the present invention. It is a figure which shows the example of the front image containing a pedestrian image, Comprising: (a) is a figure by which the front image from which position information and magnitude | size information are extracted is shown, (b) is a vehicle traveling speed. It is a figure in which the present front image on which an emphasis image is superimposed is shown using the position information and size information extracted from the front image of (a) at 30 kilometers per hour, (c) is a vehicle It is a figure in which the current front image with which an emphasis image is superimposed is shown using the positional information and magnitude | size information extracted from the front image of (a) when driving | running | working speed of 60 km / h. It is a flowchart in which the process for detecting a pedestrian image from a front image and outputting each information to a drawing part is shown. It is a flowchart in which the process for superimposing and displaying an emphasized image on a front image is shown. It is a figure in which the modification of an emphasized image is shown.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows a configuration of a night view apparatus 100 according to an embodiment of the present invention. The night view apparatus 100 detects an image 70 (hereinafter referred to as a pedestrian image) of a detection object such as a pedestrian existing in the front area 90 from a front image 50 obtained by capturing the front area 90 of the vehicle as shown in FIG. Is detected. And the night view apparatus 100 displays the front image 50 on which the emphasis image 60 for emphasizing the front image 50 was superimposed on the display screen 41 installed toward the driver's seat in the vehicle interior. Hereinafter, based on FIG.1 and FIG.2, the structure of the night view apparatus 100 and the image displayed by the night view apparatus 100 are demonstrated.

  The night view apparatus 100 is connected to the near infrared camera 10. The night view apparatus 100 includes an image processing circuit 20 that acquires a front image 50 from the near-infrared camera 10 and a liquid crystal display 40 having a display screen 41.

  The near-infrared camera 10 is an image sensor that converts the intensity of near-infrared light into an electrical signal by an image sensor and outputs it. The near-infrared camera 10 is installed so that the traveling direction of the vehicle is directed, and images the front area 90 of the vehicle. The near-infrared camera 10 can photograph the state of the front region 90 even in an environment with little visible light by detecting near-infrared light having a wavelength of about 0.7 to 2.5 micrometers. A vehicle on which the near-infrared camera 10 is mounted is provided with a near-infrared projector 11 that is configured integrally with, for example, a headlight module and projects near-infrared rays toward the front region 90. The near-infrared camera 10 is connected to the near-infrared projector 11 and starts photographing the front area 90 and causes the near-infrared projector 11 to start projecting light. The near-infrared camera 10 detects the near-infrared light reflected by the object in the front area 90, and sequentially generates the front images 50 in time series. The near-infrared camera 10 sequentially outputs the generated image data of the front image 50 toward the image processing circuit 20 by an analog electric signal such as the NTSC standard.

  The image processing circuit 20 is connected to the near-infrared camera 10, the liquid crystal display 40, and an in-vehicle local area network (LAN) 30. The image processing circuit 20 includes a plurality of processors that perform various arithmetic processes for control and drawing, a flash memory that stores a program used for the arithmetic processes and image data of the emphasized image 60, and a work area for the arithmetic processes. It is comprised by RAM etc. which function as. In addition, the image processing circuit 20 includes a communication interface for exchanging information with various in-vehicle devices connected to the in-vehicle LAN 30 through the in-vehicle LAN 30.

  The image processing circuit 20 having the above configuration includes an image acquisition unit 21, a pedestrian detection unit 23, a speed information acquisition unit 25, and a drawing unit 27 as functional blocks by causing a processor to execute a predetermined program.

  The image acquisition unit 21 sequentially acquires the image data of the front image 50 from the near-infrared camera 10 in time series. The image acquisition unit 21 converts the image data of the front image 50 acquired by the analog method into digital image data suitable for image processing. The image acquisition unit 21 sequentially outputs the converted image data of the front image 50 to the pedestrian detection unit 23 and the drawing unit 27.

  The pedestrian detection unit 23 performs a detection process for detecting the pedestrian image 70 from the front image 50 acquired from the image acquisition unit 21. In this detection process, a cut-out image having a preset size is cut out sequentially from the acquired one front image 50. Then, for each cut image, for example, Histograms of Oriented Gradients (HOG) feature values are extracted. The image processing circuit 20 stores a classifier that is used to identify the pedestrian image 70 and is constructed in advance using a large number of sample images prepared for learning. The pedestrian detection unit 23 determines whether or not the pedestrian image 70 is included in each cut-out image by examining the HOG feature amount of each cut-out image using a discriminator. The pedestrian detection unit 23 detects the pedestrian image 70 from the front image 50 by repeating the above determination process for each cut-out image.

  Furthermore, when the pedestrian image 70 is detected from the front image 50, the pedestrian detection unit 23 extracts position information and size information of the pedestrian image 70 in the front image 50. Specifically, an xy coordinate system in units of pixels is set in advance for the front image 50. The position information is, for example, coordinate data in the xy coordinate system indicating the position CP of the lower left corner of the cut-out image that is determined to include the pedestrian image 70. The size information is, for example, size data in units of pixels in the x direction and the y direction of the cutout image that is determined to include the pedestrian image 70. The pedestrian detection unit 23 extracts the position information and the size information and sequentially outputs them to the speed information acquisition unit 25.

  The speed information acquisition unit 25 acquires vehicle travel speed information (hereinafter, speed information) through the in-vehicle LAN 30 mounted on the vehicle. For example, a skid prevention device or an antilock brake system (ABS) control device is generally connected to the in-vehicle LAN 30 as a device capable of outputting vehicle speed information. The position information and size information acquired by the pedestrian detection unit 23 are input from the pedestrian detection unit 23, so that the speed information acquisition unit 25 outputs the current vehicle speed output by the skid prevention device or the like. Information is acquired through the in-vehicle LAN 30. In addition, the speed information acquisition unit 25 associates the speed information acquired through the in-vehicle LAN 30 with the position information and size information acquired from the pedestrian detection unit 23. Then, the speed information acquisition unit 25 sequentially outputs position information, size information, and speed information associated with each other to the drawing unit 27.

  The drawing unit 27 draws the front image 50 and sequentially outputs it to the liquid crystal display 40 when the pedestrian image 70 is not detected from the front image 50 by the pedestrian detection unit 23. On the other hand, when the pedestrian image 70 is detected from the front image 50 by the pedestrian detection unit 23, the drawing unit 27 superimposes the emphasized image 60 on the front image 50 and sequentially outputs it to the liquid crystal display 40. In the present embodiment, the emphasized image 60 drawn by the drawing unit 27 has a rectangular shape surrounding the pedestrian image 70 over the entire circumference. The emphasized image 60 is drawn in, for example, an orange color having excellent visibility.

  The drawing unit 27 has a plurality of layers for image processing for generating the forward image 50 on which the emphasized image 60 is superimposed. The drawing unit 27 draws the front image 50 on one of the plurality of layers (hereinafter referred to as layer 1). In addition, the drawing unit 27 draws the emphasized image 60 on another one of the plurality of layers (hereinafter referred to as layer 2).

  The drawing unit 27 first sets the size of the emphasized image 60 corresponding to the size information input from the speed information acquisition unit 25 as the reference size BS of the emphasized image 60 (reference size indicated by a broken line in FIG. 2). The BS is shown for convenience and is not displayed on the actual display screen 41). In this embodiment, the reference size BS of the emphasized image 60 matches the value of dimension data as size information. The drawing unit 27 stores in advance a function that defines the correlation between the traveling speed of the vehicle based on the speed information and the enlargement ratio of the emphasized image 60 with respect to the reference size BS. Based on this function, the drawing unit 27 sets the enlargement ratio of the emphasized image 60 that is enlarged with respect to the reference size BS as the traveling speed of the vehicle increases. Then, the drawing unit 27 draws the emphasized image 60 with the drawing size calculated by multiplying the set enlargement ratio by the reference size BS. As described above, the drawing unit 27 draws the emphasized image 60 on the layer 2 by enlarging the emphasized image 60 with respect to the reference size BS as the traveling speed of the vehicle based on the speed information increases. For example, when the vehicle speed information indicates 30 kilometers per hour (km / h), the drawing unit 27 draws the enhanced image 60 enlarged to 1.1 times the reference size BS (see FIG. 2 (b)). Further, for example, when the vehicle speed information indicates 60 km / h, the drawing unit 27 draws the emphasized image 60 enlarged to 1.3 times the reference size BS (FIG. 2 (c). )reference).

  Furthermore, when the position CP in the front image 50 of the pedestrian image 70 is in the region 50r on the right side of the center of the front image 50 in the horizontal direction, the drawing unit 27 moves the right side of the front image 50 along the horizontal direction. The enhanced image 60 is enlarged in the direction. Similarly, when the position CP in the front image 50 of the pedestrian image 70 is in the region 50l on the left side of the center of the front image 50 in the horizontal direction, the drawing unit 27 displays the front image 50 along the horizontal direction. The enhanced image 60 is enlarged and drawn in the left direction. Note that the horizontal direction of the front image 50 is along the x-axis direction.

  In the current front image 50n (see FIG. 2B, etc.) that is sequentially input from the image acquisition unit 21, the drawing unit 27 displays an enhanced image at a position CP corresponding to the position information extracted by the pedestrian detection unit 23. Layer 1 and layer 2 are combined so that 60 is superimposed. The image data of the front image 50 generated by the above combining process is sequentially output from the drawing unit 27 to the liquid crystal display 40. Accordingly, the drawing unit 27 sequentially displays the front image 50 on which the emphasized image 60 is superimposed on the display screen 41.

  The liquid crystal display 40 is a dot matrix type display device capable of color display by controlling a plurality of pixels arranged on the display screen 41. The liquid crystal display 40 provides various information to the driver by displaying various images on the display screen 41. The liquid crystal display 40 is disposed inside the instrument panel with the display screen 41 facing the driver's seat. The liquid crystal display 40 can show the state of the front area 90 to the viewer by an image formed by sequentially displaying the front image 50 acquired from the drawing unit 27 of the image processing circuit 20.

  A process in which the night view apparatus 100 described so far sequentially displays the front image 50 on which the emphasized image 60 is superimposed on the liquid crystal display 40 will be described in detail with reference to FIGS. 3 and 4. The processing described below is performed by the image processing circuit 20 together with the start of the operation of the night view device 100 by the user operating a switch for starting and stopping the operation of the night view device 100. These processes are repeated until the operation of the night view apparatus 100 is stopped based on the user's operation.

  First, based on FIG. 3, the process which detects the pedestrian image 70 from the front image 50 is demonstrated. The process shown in FIG. 3 is performed by the cooperation of the pedestrian detection unit 23 and the speed information acquisition unit 25.

  In S <b> 101, the pedestrian detection unit 23 determines whether or not there is an input of the front image 50 from the near-infrared camera 10 through the image acquisition unit 21. If the output of the front image 50 from the near-infrared camera 10 to the image acquisition unit 21 is started in S101, it is determined that there is an input of the front image 50, and the process proceeds to S102. On the other hand, when the output of the front image 50 from the near-infrared camera 10 to the image acquisition unit 21 is not started in S101, it is determined that there is no input of the front image 50, and S101 is repeated. Thus, the standby state is maintained until the output of the front image 50 is started.

  In S102, the pedestrian detection unit 23 acquires the front image 50 from the image acquisition unit 21, and proceeds to S103. In S103, the detection process which detects the pedestrian image 70 from the front image 50 acquired in S102 is implemented. In S103, when the pedestrian image 70 cannot be detected from the front image 50, the process returns to S102 again. On the other hand, when the enhanced image 60 is detected from the front image 50 in S103, the process proceeds to S104. In S104, the position information and size information of the pedestrian image 70 detected from the front image 50 are extracted, output to the speed information acquisition unit 25, and the process proceeds to S105.

  In S105, the speed information acquisition unit 25 acquires the vehicle speed information through the in-vehicle LAN 30 by acquiring the position information and the size information output from the pedestrian detection unit 23 in S104, and the process proceeds to S106. In S106, the vehicle speed information acquired in S105 is associated with the position information and size information extracted in S104. Then, the information is output to the drawing unit 27, and the process returns to S102 again. When the process of S102 to S106 is repeated by the pedestrian detection unit 23 and the speed information acquisition unit 25, when the pedestrian image 70 is reflected in the front image 50, the position information and the size of the pedestrian image 70 are displayed. Information and vehicle speed information are sequentially output to the drawing unit 27.

  Next, the process of drawing the front image 50 will be described based on FIG. The process illustrated in FIG. 4 is performed by the drawing unit 27.

  In S <b> 111, it is determined whether there is an input of the front image 50 from the near-infrared camera 10 through the image acquisition unit 21. In S111, when the output of the front image 50 from the near-infrared camera 10 to the image acquisition unit 21 is started, it is determined that there is an input of the front image 50, and the process proceeds to S112. On the other hand, if the output of the front image 50 from the near-infrared camera 10 to the image acquisition unit 21 has not been started in S111, it is determined that there is no input of the front image 50, and S111 is repeated. Accordingly, the standby state is maintained until the input of the front image 50 is started.

  In S112, the front image 50 is acquired from the image acquisition unit 21, and the process proceeds to S113. In S113, it is determined whether or not there is currently input of various types of information output from the speed information acquisition unit 25 in S105 illustrated in FIG. If it is determined in S113 that there is no input of information from the speed information acquisition unit 25, the process proceeds to S119. On the other hand, if it is determined in S113 that there is input of information from the speed information acquisition unit 25, the process proceeds to S114. In S114, the position information, the size information, and the speed information output from the speed information acquisition unit 25 are acquired, and the process proceeds to S115. Here, the front image 50 obtained by extracting the position information and the size information acquired in S114 is different from the front image 50 acquired in S112.

  In S115, the reference size BS of the emphasized image 60 is set based on the size information acquired in S114. In addition, in S115, the enlargement ratio of the emphasized image 60 is set based on the vehicle speed information acquired in S114, and the process proceeds to S116. In S116, the drawing size of the emphasized image 60 is determined by multiplying the reference size BS set in S115 by the enlargement ratio set in S115, and the process proceeds to S117. According to these processes of S115 and S116, the drawing size of the emphasized image 60 is greatly enlarged with respect to the reference size BS corresponding to the size information as the traveling speed of the vehicle increases.

  In S117, the front image 50 acquired in S112 is drawn on layer 1. In addition, in S117, the emphasized image 60 is drawn on the layer 2 with the drawing size set in S116, and the process proceeds to S118. In S117, when the position CP of the pedestrian image 70 based on the position information acquired in S115 is in the region 50r on the right side of the front image 50, the emphasized image 60 is displayed along the horizontal direction with the position CP as a base point. (See FIG. 2B and the like). In addition, the emphasized image 60 is enlarged above the front image 50 along the vertical direction with the position CP as a base point.

  In S118, the layer 2 in which the emphasized image 60 is drawn is combined with the layer 1 in which the forward image 50 is drawn, so that the emphasized image 60 is superimposed on the position CP corresponding to the position information acquired in S114. Image data of the image 50 is generated. Then, the process proceeds to S120. On the other hand, in S119 performed when there is no input of various types of information from the pedestrian detection unit 23, the image data of the front image 50 is drawn by drawing the front image 50 acquired in S112 on the layer 1. Generate and proceed to S120. In S120, the image data of the front image 50 generated by one of S118 and S119 is output to the liquid crystal display 40, and the process returns to S112 again.

  When the pedestrian image 70 is reflected in the front image 50 by repeating the above S112 to S120, the image is enlarged to the position CP corresponding to the position information in the current front image 50 sequentially acquired by the image acquisition unit 21. The emphasized image 60 drawn in this manner is superimposed. The current front image 50n is continuously output to the liquid crystal display 40. Thereby, the state of the front area 90 is displayed on the liquid crystal display 40 as a moving image by the front images 50 displayed sequentially.

  In the present embodiment described so far, the process of extracting the position information and the size information of the pedestrian image 70 requires time. Therefore, the front image 50p (see FIG. 2A) from which the position information and the size information are extracted with respect to the front image 50n on which the emphasized image 60 is superimposed (see FIGS. 2B and 2C). , Become a thing of the past. Even during the time when the pedestrian detection unit 23 extracts the position information and the size information of the pedestrian image 70, the vehicle is approaching the actual detection target existing in the front area 90. Therefore, the pedestrian image 70 in the current front image 50n sequentially acquired by the image acquisition unit 21 is the pedestrian image 70 in the past front image 50p in which the position information and the size information are extracted by the pedestrian detection unit 23. Rather than the front image 50n. Furthermore, as the traveling speed of the vehicle increases, the pedestrian image 70 in the current front image 50n is greatly enlarged with respect to the pedestrian image 70 in the past front image 50p and appears in the front image 50n.

  Therefore, in the present embodiment, the emphasized image 60 is greatly enlarged as the traveling speed of the vehicle increases. Thereby, the size of the emphasized image 60 can correspond exactly to the size of the pedestrian image 70 shown in the current front image 50n. In addition, the drawing unit 27 sequentially displays the current front image 50n sequentially acquired by the image acquisition unit 21 so as to be sequentially displayed on the liquid crystal display 40. Therefore, since the structure for buffering the front image 50 can be omitted, complication of the night view apparatus 100 is avoided. In addition, the display delay of the display screen 41 is reduced as compared with the mode in which the front image 50 is buffered. As described above, the night view apparatus 100 maintains the simple configuration, suppresses the delay in displaying the front image 50, and accurately superimposes the emphasized image 60 on the front image 50, thereby the pedestrian image 70. Can be emphasized.

  In addition, according to the present embodiment, the speed information acquisition unit 25 acquires speed information by acquiring position information and size information from the pedestrian detection unit 23. Therefore, the difference between the timing at which the position information and the size information are extracted by the pedestrian detection unit 23 and the timing at which the speed information associated with these information is acquired by the speed information acquisition unit 25 is reduced. Here, the ratio of the size of the pedestrian image 70 in the current front image 50n to the size of the pedestrian image 70 in the past front image 50p corresponds to the traveling speed of the vehicle. Therefore, by reducing the difference between the timing at which position information and size information are extracted and the timing at which speed information is acquired, the drawing unit 27 accurately reflects the traveling speed of the vehicle in the enlargement of the emphasized image 60. Can do. As described above, the drawing unit 27 can draw the emphasized image 60 that exactly corresponds to the size of the pedestrian image 70 in the current front image 50n. Therefore, the night view apparatus 100 can emphasize the pedestrian image 70 by more accurately superimposing the pedestrian image 70 on the enhanced image 60.

  In addition, according to the present embodiment, the drawing size of the emphasized image 60 is calculated by multiplying the enlargement ratio that is set larger as the traveling speed of the vehicle increases by the reference size BS. In the above embodiment, the drawing size of the emphasized image 60 is surely increased as the traveling speed of the vehicle is increased, so that the size of the pedestrian image 70 in the current front image 50n can be more accurately handled. Therefore, the night view device 100 can emphasize the pedestrian image 70 by more accurately superimposing the enhanced image 60 on the pedestrian image 70.

  Furthermore, in this embodiment, when the pedestrian image 70 is reflected in the area 50r on the right side of the front image 50, the pedestrian image 70 is aligned along the horizontal direction due to the approach of the actual pedestrian existing in the front area 90 and the vehicle. Thus, the image becomes larger while moving in the right direction of the front image 50 (see FIG. 2C and the like). Therefore, the emphasized image 60 can be accurately corresponding to the position and size of the pedestrian image 70 in the current front image 50n by being enlarged and drawn in the right direction of the front image 50.

  Similarly, when the pedestrian image 70 is reflected in the region 50l on the left side of the center of the front image 50 in the horizontal direction, the pedestrian image 70 is horizontal due to the approach of the actual pedestrian existing in the front region 90 and the vehicle. While moving in the left direction of the front image 50 along the direction, it becomes larger. Therefore, the emphasized image 60 can be accurately corresponding to the position and size of the pedestrian image 70 in the current front image 50n by being drawn enlarged in the left direction of the front image 50.

  Accordingly, the night view apparatus 100 can emphasize the pedestrian image 70 by more accurately superimposing the emphasized image 60 on the pedestrian image 70.

  Further, as described above, the ratio of the size of the current pedestrian image 70 to the size of the past pedestrian image 70 corresponds to the traveling speed of the vehicle. Therefore, as in the present embodiment, by previously defining the correlation between the traveling speed of the vehicle and the enlargement ratio of the emphasized image 60 by a function, the enlargement ratio can be set finely for each traveling speed of the vehicle. Thus, by appropriately adjusting the function, the drawing size of the enlarged emphasized image 60 and the current size of the pedestrian image 70 can be associated with each other with certainty. The pedestrian image 70 can be further emphasized by 60.

  In addition, according to the present embodiment, the emphasized image 60 that surrounds the pedestrian image 70 overlaps the pedestrian image 70 if the drawing size does not correspond to the size of the pedestrian image 70. This makes it difficult to see the pedestrian image 70. However, as described above, the drawing size of the emphasized image 60 from the drawing unit 27 that enlarges and draws the emphasized image 60 based on the traveling speed of the vehicle is the pedestrian in the current front image 50n displayed on the display screen 41. The size of the image 70 can be accurately handled. Therefore, even if it is the emphasis image 60 of the shape surrounding the pedestrian image 70, the situation which makes it difficult to see the pedestrian image 70 is avoided, and the effect of emphasizing the pedestrian image 70 is surely exhibited. become. As described above, the night view device 100 that superimposes the emphasized image 60 surrounding the pedestrian image 70 on the front image 50 can further enhance the pedestrian image 70 by enlarging the emphasized image 60 according to the traveling speed. .

  In the present embodiment, the near-infrared camera 10 corresponds to the “imaging means” recited in the claims, the image acquisition unit 21 corresponds to the “image acquisition means” recited in the claims, and the pedestrian The detection unit 23 corresponds to the “object information extraction unit” described in the claims, the speed information acquisition unit 25 corresponds to the “speed information acquisition unit” described in the claims, and the drawing unit 27 includes the patent. It corresponds to the “drawing means”, the “magnification setting unit”, and the “drawing part” described in the claims, and the drawing unit 27 and the liquid crystal display 40 cooperate to form the “display means” described in the claims. The pedestrian image 70 corresponds to the “image of the detection target” described in the claims, and the night view device 100 corresponds to the “vehicle display device” described in the claims.

(Other embodiments)
Although one embodiment according to the present invention has been described above, the present invention is not construed as being limited to the above-described embodiment, and can be applied to various embodiments without departing from the gist of the present invention. it can.

  In the above embodiment, the speed information acquisition unit 25 acquires the speed information from the in-vehicle LAN 30 by acquiring the position information and the size information output from the pedestrian detection unit 23. However, the timing at which the speed information acquisition unit acquires the speed information may not be immediately after the information is received from the pedestrian detection unit as in the above embodiment. For example, the pedestrian detection unit acquires and stores the current speed information for each preset time, thereby storing the current speed information stored in the position information and the size information acquired from the pedestrian detection unit. May be associated. Further, the night view apparatus may include a sensor for measuring the rotational speed of the tire as a “speed information acquisition unit” instead of the configuration such as the speed information acquisition unit 25 that acquires the speed information from the in-vehicle LAN 30. Good.

  In the above embodiment, the drawing unit 27 sets the drawing size of the emphasized image 60 by multiplying the reference size BS by the enlargement factor. The enlargement ratio is calculated by inputting the traveling speed of the vehicle to a predetermined function. Such a function used by the drawing unit 27 may output a magnification as a discrete value with respect to a traveling speed as an input, or output a magnification as a continuous value. There may be. In addition, in a range where the traveling speed as an input is low, for example, a magnification of 1 may be maintained regardless of the traveling speed. Further, the method of setting the drawing size by the drawing unit is not limited to the above method of multiplying the reference size BS by the enlargement ratio. For example, a table for determining the drawing size based on the traveling speed of the vehicle and the reference size BS is defined in advance. Then, based on this table, the drawing unit may determine the drawing size of the emphasized image.

  In the above embodiment, the reference size BS of the emphasized image 60 is determined so as to coincide with the dimension data of the cut-out image. However, the reference size of the emphasized image corresponding to the size information may not match the dimension data of the cut image. For example, a value obtained by adding or subtracting a predetermined value to the dimension data of the cutout image may be determined as the reference size of the emphasized image. Alternatively, a value obtained by multiplying the dimension data of the cutout image by a predetermined value may be determined as the reference size of the emphasized image.

  In the above embodiment, the enlargement ratio for enlarging the emphasized image 60 is set to 1.1 times at 30 km / h and 1.3 times at 60 km / h. However, the specific value of the enlargement ratio is determined by, for example, the emphasis image accurately matching the pedestrian image according to the angle of view of the lens included in the near-infrared camera that generates the front image, the attachment position of the near-infrared camera to the vehicle, and the like. It may be adjusted appropriately so that it can be emphasized.

  In the above embodiment, the emphasized image 60 is enlarged in the right direction of the front image 50 when the pedestrian image 70 appears in the right region 50 r of the front image 50, and the pedestrian image 70 is the left region of the front image 50. In the case of 50 l, the image was enlarged in the left direction of the front image 50. In addition, the lower left corner of the pedestrian image is a position CP that is the base point of enlargement. However, the position of the base point for enlarging the emphasized image and the direction for enlarging may be changed as appropriate according to the horizontal and vertical positions of the pedestrian image in the front image, the traveling speed of the vehicle, and the like. For example, when the pedestrian image is reflected in the left region of the front image, the lower right corner of the pedestrian image may be set as the position of the enlargement base point. Alternatively, the emphasized image may be enlarged in the horizontal direction and the vertical direction with the center of the pedestrian image as the position of the enlargement base point.

  In the embodiment described above, the emphasized image 60 is a rectangular image that surrounds the pedestrian image 70 with a solid line over the entire circumference. However, the shape of the enhanced image is not limited to the above shape. For example, as illustrated in FIG. 5A, the enhanced image 260 may be a rectangular image that surrounds the pedestrian image 70 with a broken line over the entire circumference. Or as FIG.5 (b) shows, the emphasis image 360 may be a rectangular frame-shaped image which pinches | interposes the pedestrian image 70 in a horizontal direction. Furthermore, as illustrated in FIG. 5C, the enhanced image 460 may be a rectangular frame image that sandwiches the pedestrian image 70 in the vertical direction. Alternatively, as illustrated in FIG. 5D, the emphasized image 460 may be an image that simulates the shape of a detection target such as a pedestrian and is superimposed on the detection target image 70. Furthermore, the emphasized image may not surround the pedestrian image. For example, the enhanced image may be a bar-shaped image that is superimposed adjacent to the image of the detection target and extends in the vertical direction or the horizontal direction along the image of the detection target.

  In the above embodiment, the emphasized image 60 is an orange image having excellent visibility, for example. However, the hue, brightness, saturation, and the like of the emphasized image may be changed as appropriate. In addition, the enhanced image may be a translucent image so as not to hinder the viewing of the pedestrian image by the viewer. Alternatively, the emphasized image may be a blinking image that repeats display and non-display so as to easily attract the viewer's attention.

  In the above-described embodiment, the night view apparatus 100 is connected to the near-infrared camera 10 as “imaging means”. However, the “imaging device” that outputs the front image to the night view device is not limited to the above-described embodiment as long as it can capture an image of the front area of the vehicle. For example, the “imaging means” may be a visible light camera that captures a front image by detecting visible light. Alternatively, it may be a far-infrared camera that captures a front image by detecting far-infrared rays. Furthermore, the night view apparatus may include a configuration corresponding to “imaging means”.

  In the above embodiment, the night view apparatus 100 includes a liquid crystal display as part of the “display unit”. However, the night view device may include a so-called head-up display device that projects a front image on a window shield of a vehicle and forms an image in front of the window shield instead of the liquid crystal display. Alternatively, the “display unit” of the night view device may be an output unit that outputs a front image toward an external display device such as a liquid crystal display provided in the navigation system.

  In the above-described embodiment, the drawing unit 27 draws the front image 50 and the emphasized image 60 on different layers, and performs a combining process for combining these layers, thereby superimposing the emphasized image 60 on the front image 50. It was. However, the drawing unit may superimpose the enhanced image on the front image by directly updating the gradation data of the pixels corresponding to the superimposed portion of the enhanced image in the front image.

  In the embodiment described above, the program is executed by the image processing circuit 20, whereby the pedestrian detection unit 23 and the drawing unit 27 as functional blocks are configured. However, the functions of the functional blocks may be performed by different circuits. The circuit functioning as each functional block may be a circuit that performs a predetermined function by executing a program by a processor, such as an image processing circuit, or may be an analog circuit that does not execute a program. Good.

  In the said embodiment, the night view apparatus detected the pedestrian as a detection target object. However, the detection target detected by the night view device is not limited to a pedestrian. For example, a person who rides in a vehicle, a bicycle or a two-wheeled vehicle, an animal such as a deer or a spider may be set in advance as a detection target.

BS-enhanced image reference size, CP pedestrian image position, 10 near-infrared camera (imaging means), 11 near-infrared projector, 20 image processing circuit, 21 image acquisition unit (image acquisition unit), 23 pedestrian detection unit (target Object information extraction means), 25 speed information acquisition section (speed information acquisition means), 27 drawing section (drawing means, enlargement ratio setting section, drawing section, display means), 30 in-vehicle LAN, 40 liquid crystal display (display means), 41 Display screen, 50 forward image, 50r right region, 50l left region, 50n current forward image, 50p past forward image, 60 weighted image, 70 pedestrian image (detected object image), 90 forward region, 100 Night view device (vehicle display device)

Claims (5)

An image of a detection target existing in the front area is detected from a front image sequentially generated by an imaging unit that captures a front area of the vehicle, and an enhanced image that emphasizes the image of the detection target is superimposed on the front image. A vehicle display device that sequentially displays,
Image acquisition means for sequentially acquiring the front images from the imaging means;
Object information extracting means for extracting position information and size information of the image of the detection object in the front image by detecting the image of the detection object from the front image acquired by the image acquisition means; ,
Speed information acquisition means for acquiring information on the traveling speed of the vehicle;
The size of the emphasized image corresponding to the size information extracted by the object information extracting unit is set as a reference size, and the emphasized image is changed as the traveling speed by the information acquired by the speed information acquiring unit increases. A drawing means for drawing with a large enlargement with respect to the reference size;
In the current front image sequentially acquired by the image acquisition unit, the emphasized image drawn by the drawing unit at a position corresponding to the position information extracted by the object information extraction unit is enlarged. Display means for superimposing and sequentially displaying;
A vehicle display device comprising: The speed information acquisition means acquires the travel speed information by acquiring the position information and the size information by the object information extraction means, and also adds the travel speed to the position information and the size information. Associate information with
The drawing unit enlarges the emphasized image greatly with respect to the reference size corresponding to the size information associated with the travel speed information by the speed information acquisition unit as the travel speed increases. The vehicle display device according to claim 1, wherein the display device is drawn. The drawing means includes
An enlargement rate setting unit for setting an enlargement rate of the emphasized image enlarged with respect to the reference size as the traveling speed of the vehicle increases;
A drawing unit for drawing the emphasized image at a drawing size calculated by multiplying the enlargement rate set by the enlargement rate setting unit by the reference size;
The vehicle display device according to claim 1, further comprising: The drawing means includes
When the position of the image of the detection object according to the position information in the front image is in a region on the right side of the center of the front image in the horizontal direction, the right direction of the front image along the horizontal direction Enlarge and draw the emphasized image,
When the position of the image of the detection object based on the position information in the front image is in a region on the left side of the center of the front image in the horizontal direction, the image is detected in the left direction of the front image along the horizontal direction. The vehicle display device according to claim 1, wherein the emphasized image is enlarged and drawn.   5. The vehicle display device according to claim 1, wherein the drawing unit draws the emphasized image having a shape surrounding an image of the detection object.

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