Patent Publication Number: US-9428111-B2

Title: Vehicle video system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation that claims priority under 35 U.S.C. §120 to U.S. application Ser. No. 13/608,646, filed on Sep. 10, 2012, the entire contents of which are hereby incorporated herein by reference. 
    
    
     BACKGROUND 
     1. Field of the Invention 
     The present invention generally relates to a vehicle video system. More specifically, the present invention relates to vehicle video system that includes a camera aimed to capture video images of a cargo area of the vehicle and a system for converting video images captured by the camera into a simulated overhead view of the cargo area. 
     2. Background Information 
     Many vehicles have been provided with video cameras, primarily video cameras that provide captured images of areas rearward of the vehicle. One such vehicle includes a display mounted to or installed within an instrument panel of the vehicle, the display showing streaming video images of the areas rearward of the vehicle captured by the video camera. The streaming video images of the areas rearward of the vehicle are displayed in order to assist the driver of the vehicle during the process of parking the vehicle, or for other maneuvers, where the vehicle is moving in reverse (moving backward). 
     Similarly, a plurality of video cameras have been mounted to a front end and sides of the vehicle such that the driver can observe the streaming video on the display of the images captured by one or all of the plurality of cameras. The plurality of cameras are for the purpose of providing streaming video that the driver can observe while parking the vehicle, to avoid contact with other parked vehicles or stationary objects. Thus, the driver of the vehicle is able to observe movement and/or the location of objects within the areas outside and adjacent to the vehicle as captured by the plurality of cameras. 
     SUMMARY 
     One object is to provide a vehicle having a cargo area with a camera that captures video images of the cargo area, with the captured video images being used to generate a simulated overhead view of the cargo area such that the vehicle operator can view a streaming video of the cargo area on a display within the vehicle. 
     In view of the state of the known technology, in one aspect of the present disclosure, a method for capturing and displaying images, includes fixedly attaching a first video camera to a vehicle at a first fixed location in a prescribed orientation relative to a cargo area defined within a vehicle body structure of a vehicle; providing an electronic display within the vehicle; capturing video images of the cargo area using the first video camera; processing the video images of the cargo area captured by the first video camera and generating a simulated video overhead view of the cargo area; and, displaying on the electronic display a still image representing an overhead view of the vehicle, and superimposing on the display on an area of the still image corresponding to the location of the cargo area the generated simulated video overhead view of the cargo area. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Referring now to the attached drawings which form a part of this original disclosure: 
         FIG. 1  is a perspective view of a vehicle that includes a cargo area, the vehicle having a vehicle video system with a camera positioned to capture video of the cargo area in accordance with a first embodiment; 
         FIG. 2  is a schematic view of the vehicle video system showing a plurality of cameras, including a front camera, a rear camera, a passenger&#39;s side camera and a driver&#39;s side camera, the cargo area camera, an image processor and a video display in accordance with the first embodiment; 
         FIG. 3  is a view of a passenger compartment of the vehicle showing the video display of the vehicle video system in an instrument panel in accordance with the first embodiment; 
         FIG. 4  is a front view of the vehicle showing the position of the front camera of the vehicle video system in accordance with the first embodiment; 
         FIG. 5  is a perspective view of a rear portion of the vehicle showing the position of the rear camera on a tailgate of the vehicle in accordance with the first embodiment; 
         FIG. 6  is another perspective view of the vehicle showing the position of the driver&#39;s side camera (and indicating the position of the passenger&#39;s side camera) on a side view mirror assembly of the vehicle in accordance with the first embodiment; 
         FIG. 7  is a rear view of a rear portion of a cabin structure of the vehicle showing the position of the cargo area camera in accordance with the first embodiment; 
         FIG. 8  is another perspective view depicting the rear portion of the cabin structure of the vehicle further showing the position of the rear camera in accordance with the first embodiment; 
         FIG. 9  is a schematic view of the vehicle showing a virtual or imaginary point above the vehicle pre-programmed into the image processor for generating simulated overhead views of the cargo area and areas around the vehicle (as indicated in  FIG. 13 ), the image processor using video captured by the cargo area camera, the front camera, the rear camera, the passenger&#39;s side camera and the driver&#39;s side camera, in accordance with the first embodiment; 
         FIG. 10  is a flowchart showing operational steps performed by the image processor in accordance with the first embodiment; 
         FIG. 11  is schematic view of the video display with a split screen, one side (the left side) showing the video captured by the cargo area camera and the other side (the right side) streaming a simulated overhead view streaming at least a portion of the cargo area and areas adjacent to the rear of the vehicle superimposed over a still image of the vehicle in accordance with the first embodiment; 
         FIG. 12  is another schematic view of the video display with the split screen, one side streaming the video captured by the cargo area camera and the other side streaming a simulated overhead view of the cargo area that is squared off and superimposed over the still image of the vehicle in accordance with the first embodiment; 
         FIG. 13  is another schematic view of the video display with the split screen, one side streaming the video captured by the cargo area camera and the other side streaming the simulated overhead view of the cargo area and simulated overhead views of each of the areas around the vehicle captured by the front, rear, passenger&#39;s side and driver&#39;s side cameras, all superimposed over the still image of the vehicle in accordance with the first embodiment; 
         FIG. 14  is another schematic view of the video display with the split screen, one side streaming the video captured by the cargo area camera with the tailgate down and the other side streaming a simulated overhead view the cargo area and simulated overhead views of each of the areas around the vehicle captured by the front, passenger&#39;s side and driver&#39;s side cameras, all superimposed over the still image of the vehicle, with an area rearward from the vehicle being captured by the cargo area camera in accordance with the first embodiment; 
         FIG. 15  is a top view of the vehicle showing an indication of a field of view of the rear camera with the tailgate down, with a trailer rearward of the vehicle and with the vehicle aligning with the trailer in order to connect to the trailer in accordance with the first embodiment; 
         FIG. 16  is another schematic view of the vehicle showing the imaginary point above the vehicle determined by the image processor for producing the simulated overhead views of the areas around the vehicle as indicated in  FIG. 14 , using video captured by the cargo area camera, the front camera, the passenger&#39;s side camera and the driver&#39;s side camera, with the rear camera being disabled and the cargo area camera capturing video images of the cargo area and an area rearward of the vehicle, in accordance with the first embodiment; 
         FIG. 17  is a schematic view of a vehicle showing an imaginary point above the vehicle pre-programmed into the image processor for producing simulated overhead views of an internal cargo area of the vehicle and areas around the vehicle as indicated in  FIG. 18 , using video captured by a cargo area camera, a front camera, a rear camera, a passenger&#39;s side camera and a driver&#39;s side camera, in accordance with a second embodiment; 
         FIG. 18  is a schematic view of a video display with the split screen, one side showing the video captured by the cargo area camera and the other side showing a simulated overhead of view the cargo area and simulated overhead views of each of the areas around the vehicle captured by the front, rear, passenger&#39;s side and driver&#39;s side cameras, all superimposed over a still image of the vehicle in accordance with the second embodiment; 
         FIG. 19  is a rear view of a cabin structure portion of a vehicle showing two cargo area cameras in accordance with a third embodiment; and 
         FIG. 20  is an overhead view of the vehicle showing the approximate areas captured by the two cargo area cameras in accordance with the third embodiment. 
     
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
     Selected embodiments will now be explained with reference to the drawings. It will be apparent to those skilled in the art from this disclosure that the following descriptions of the embodiments are provided for illustration only and not for the purpose of limiting the invention as defined by the appended claims and their equivalents. 
     Referring initially to  FIG. 1 , a vehicle  10  is illustrated in accordance with a first embodiment. The vehicle  10  includes a video system  12  depicted schematically in  FIG. 2 , and is described in greater detail below. 
     The vehicle  10  includes a vehicle body  16  with a front end  18 , a rear end  20 , a driver&#39;s side  22 , a passenger&#39;s side  24 , a cargo area  26  and a cabin structure  28  with a passenger compartment  30  therein. It should be understood that the driver&#39;s side  22  and the passenger&#39;s side  24  are merely labeled as such with reference to a left-hand drive vehicle and that the functionality of the video system  12  according to the present invention can be identical in a right-hand drive vehicle. The driver&#39;s side  22  includes a driver&#39;s side mirror assembly  32 , and the passenger&#39;s side  24  includes a passenger&#39;s side mirror assembly  34 . The cargo area  26  can include a variety of features, for example, a tailgate  36  and a trailer hitch receiver  38 . As shown in  FIG. 1 , the cargo area  26  is a conventional pickup truck structure that includes a floor  26   a  and side walls  26   b  that define an interior space  26   c  that is configured to receive cargo (not shown). An upper area of an interior space  26   c  of the cargo area  26  is exposed in a conventional manner. The interior space  25   c  of the cargo area  26  is defined between side walls  26   a  and the floor  26   b  of the cargo area  26 . The tailgate  36  (a movable member) is movable between a closed position ( FIG. 1 ) confining a rear portion of the interior space  26   c  of the cargo area  26  and an open position (indicated in  FIGS. 14-16 ) providing easy access to the rear portion of the interior space  26   c  of the cargo area  26 . The tailgate  36  can also be completely removed from the vehicle  10 . 
     The passenger compartment  30  includes an instrument panel  40 , as shown in  FIG. 3 . The instrument panel  40  includes a variety of features, such as lighting switches, air conditioning controls, radio, an ignition switch  42  (only shown in  FIG. 2 ), a display  44  and a video control panel  46 . 
     As shown in  FIG. 2 , the video system  12  includes the display  44 , the video control panel  46 , vehicle sensors  48 , an image processor  50 , a front camera  52 , a rear camera  54 , a passenger&#39;s side camera  56 , a driver&#39;s side camera  58  and a cargo area camera  60 . 
     In the depicted embodiment of the video system  12 , there are five cameras, the front camera  52 , the rear camera  54 , the passenger&#39;s side camera  56 , the driver&#39;s side camera  58  and the cargo area camera  60 . However, it should be understood from the drawings and the description herein that the number of cameras installed to the vehicle  10  can be varied. For example, in one embodiment, the vehicle  10  can be provided with just one camera (e.g., the cargo area camera  60 ), multiple cargo area cameras, and/or the plurality of video cameras depicted schematically in  FIG. 2  capturing video images of the area around the periphery of the vehicle  10 , as described below. 
     In the description of the video system  12 , several terms are used in a manner consistent with the definitions provided below. 
     Specifically, the terms “video”, “video image” or “video images” as used herein refer to a series of captured images showing current movement or lack of movement in a predetermined area captured by each respective one of the plurality of cameras including the cargo area camera  60 . 
     The term “simulated live overhead view” as used herein refers to a video image of an area that is captured by one or more cameras that are not physically oriented capture a literal top plan view of the area. Rather, the captured video images are processed to generate or form an appearance of a top plan view of the corresponding area. 
     The terms “stream”, “streaming”, “streaming video”, or other similar forms as used herein include storing the video image in a storage device (e.g. RAM, hard drive, FLASH memory, etc.,) prior to displaying. However, preferably, the streaming has only a prescribed amount of latency (125 milliseconds delay or less—125 milliseconds is ⅛ th  of a second) between the moment of capture and the moment the video image or video images are displayed on the display  44 . 
     As is described in greater detail below, the display  44  is configured to display a variety of video images in the form of streaming video. Specifically, the display  44  receives processed video data from the image processor  50  based upon video images captured by one, selected ones or all of the plurality of cameras of the video system  12  depicted in  FIG. 2 . The display  44  can be configured in any of a variety of ways. For example, the display  44  can display: streaming video from just one selected camera at a time; streaming video from all of the cameras; or a simulated overhead view where some or all of the captured video images are manipulated by the image processor  50  and then superimposed over a still image of the vehicle  10 , to produce the simulated overhead view of the vehicle  10  and surrounding areas on all sides of the vehicle  10 , as is described in greater detail below. In the depicted embodiments, the display  44  is also configured to provide a split screen where half of the viewing area of the display  44  shows the actual streaming video images from the selected camera and the other half of the display  44  shows a selected overhead simulated view of the vehicle  10  and the areas around the vehicle  10 . 
     The video control panel  46  in the instrument panel  40  is provided with one or more controls that allow an occupant of the vehicle  10  to select the type of view desired for output on the display  44 . For example, the video control panel  46  can be provided with quick glance buttons or inputs (not shown) that cause the image processor  50  to stream captured images from a specific one of the plurality of cameras for just a short, predetermined period of time. One example of such a quick glance button includes a request to stream the captured video from the passenger&#39;s side camera  38  for ten (10) to fifteen (15) seconds to the display  44  so that the driver monitor the status of objects within the field of view of the passenger&#39;s side camera  38 . Another example of a quick glance button includes a request to stream the captured video from the cargo area camera  60  for ten (10) seconds to fifteen (15) seconds so that the driver monitor the status of objects in the cargo area  26 . Other features of the video system  12  are explained in greater detail below. 
     The vehicle sensors  48  vary from vehicle to vehicle. The vehicle sensors  48  can be a single sensor or an array of sensors. However in the depicted embodiment, the vehicle sensors  48  can include a vehicle speed sensor (not shown), a transmission sensor (not shown) and a tailgate position sensor within the tailgate  36  or at the rear end  20  of the vehicle  10 . The speed sensor provides vehicle speed information to the image processor  50  such that, below a prescribed speed, the image processor automatically sets the display  44  to, for example, display a video image captured by a predetermined one of the cameras, or alternatively, can shut off the display  44  during high speed operation of the vehicle  10  (e.g., above speeds typically associated with parking procedures). The transmission sensor can be configured to provide the image processor  50  with the status of the transmission of the vehicle  10 . For example, when the transmission is set in reverse such that the vehicle  10  is capable of moving rearward, the video image captured by the rear camera  54  can be automatically displayed on the display  44 . The tailgate position sensor provides an indication of the position of the tailgate  36 . As is described in greater detail below, when the tailgate  36  is in an open position, the performance of the rear camera  54  may be compromised. The tailgate position sensor of the plurality of sensors  48  provides the image processor  50  with an indication of the status of the rear camera  54 . 
     The image processor  50  is configured to process the various video images captured by the plurality of cameras  52 ,  54 ,  56 ,  58  and  60  in a manner described in greater detail below. The image processor  50  preferably includes a microcomputer (i.e., a central processing unit or CPU) with a video processing control program that processes streaming video output to the display  44 . The image processor  50  can also include other conventional components such as an input interface circuit, an output interface circuit, and storage devices such as a ROM (Read Only Memory) device and a RAM (Random Access Memory) device. The microcomputer of the image processor  50  is programmed to process the video images from the plurality of cameras in order to generate simulated overhead views of the areas captured by each of the plurality of cameras, as is described in greater detail below. The memory circuit stores processing results and control programs such as ones for video processing operations that are run by the image processor  50 . The image processor  50  is operatively coupled to the plurality of cameras and the display  44  in a conventional manner, such as by coaxial cables, computer cables, wireless connections or other similar configurations capable of transferring video images or video data from one location to another within a vehicle. The internal RAM of the image processor  50  stores statuses of operational flags and various control data. The internal ROM of the image processor  50  stores image data and transformational data for various operations. The image processor  50  is capable of selectively controlling any of the components of the video system  12  in accordance with the control program. It will be apparent to those skilled in the art from this disclosure that the precise structure and algorithms for the image processor  50  can be any combination of hardware and software that will carry out the functions of the present invention. 
     It should also be understood from the drawings and the description herein that the image processor  50  can be programmed to stream any of a variety of combinations of video images to the display  44 . The depictions of the display  44  and its streamed content shown in  FIGS. 11-14  are some examples of the types of streamed video images that can be shown in the display  44 . However, the present invention is not limited to the examples of streamed video images shown on the display  44  in  FIGS. 11-14 . The display  44  can show a full screen video image or multiple split screen configurations depending upon the pre-programming and configuration of the image processor  50 . 
     A description of the plurality of cameras is now provided with respect to  FIGS. 1 and 4-8 . As shown in  FIG. 4 , the front camera  52  is fixedly attached to the vehicle body  16  at the front end  18  of the vehicle  10 . In the depicted embodiment, the front camera  52  is fixedly attached to an emblem of the front grille at the front end  18  of the vehicle  10 . The front camera  52  is fixed in position relative to the front end  18  such that the front camera  52  captures video of the area frontward of the front end  18  of the vehicle  10 . The front camera  52  is aimed downwardly, but is angled relative to vertical so that the front camera  52  is aimed at the area frontward of the front end  18  of the vehicle  10 . The angle A F1  in  FIG. 4  provides an approximate frontal indication of the field of view captured by the front camera  52 . The angle A F2  in  FIG. 9  shows an approximate side indication of the field of view captured by the front camera  52 . 
     As shown in  FIGS. 1 and 5 , the rear camera  54  is fixedly attached the tailgate  36  at the rear end  20  of the vehicle  10 . In the depicted embodiment, the rear camera  54  is fixed to a plate or housing of the latch release handle of the tailgate  36 . The rear camera  54  is fixed in position relative to the tailgate  36  such that the rear camera  54  captures the area rearward of the rear end  20  of the vehicle  10 . With the tailgate  36  in the closed position, the rear camera  54  is aimed downwardly, but is angled relative to vertical so that the rear camera  54  is aimed at the area rearward of the rear end  20  of the vehicle  10 . The angle A R1  in  FIG. 1  provides an approximate indication of the side-to-side field of view captured by the rear camera  54 . The angle A R2  in  FIG. 9  shows an approximate side indication of the rearward field of view captured by the rear camera  54 . 
     As shown in  FIG. 6 , the driver&#39;s side camera  58  is fixedly attached an underside of the driver&#39;s side mirror assembly  32  at the driver&#39;s side  22  of the vehicle  10 . The passenger&#39;s side camera  56  is similarly attached to an underside of the passenger&#39;s side mirror assembly  34 . The driver&#39;s side camera  58  is fixed in position relative to the driver&#39;s side mirror assembly  32  with the driver&#39;s door closed such that the driver&#39;s side camera  58  captures the area along the side of the driver&#39;s side  22  of the vehicle  10 . The angle ADS in  FIG. 9  provides an approximate indication of the field of view captured by the driver&#39;s side camera  58 . 
     Since the passenger&#39;s side camera  56  is symmetrically installed to the passenger&#39;s side mirror assembly  34  in a manner consistent with the driver&#39;s side camera  58 , further description of the passenger&#39;s side camera  56  is omitted for the sake of brevity. 
     As shown in  FIGS. 1, 7 and 8 , the cargo area camera  60  is fixedly attached the rearward end of the roof of the cabin structure  30  of the vehicle  10 . The cargo area camera  60  is fixed in position relative to the cabin structure  28  such that the cargo area camera  60  captures the cargo area  26  and areas rearward of the rear end  20  of the vehicle  10  when the tailgate  36  is in the down or open position. The cargo area camera  60  is aimed downwardly, but is angled relative to vertical so that the cargo area camera  60  is aimed primarily at the cargo area  26 , but as is described further below, the cargo area camera  60  can also capture the area rearward of the rear end  20  of the vehicle  10  with the tailgate  36  in the open position. The angle A C1  in  FIGS. 1 and 7  provides an approximate indication of the side-to-side field of view captured by the cargo area camera  60 . The angle A C2  in  FIG. 9  provides an approximate side indication of the rearward field of view captured by the cargo area camera  60 . 
     Each of the plurality of cameras (the front camera  52 , the rear camera  54 , the passenger&#39;s side camera  56 , the driver&#39;s side camera  58  and the cargo area camera  60 ) are installed at predetermined, fixed locations relative to the vehicle body  16 . These predetermined, fixed locations are used by the image processor  50  such that a simulated overhead view is generated, as described below. As is explained in greater detail below, the generation of each of the simulated overhead views from the images captured by each of the plurality of cameras requires that the position of each camera relative to the vehicle body  16  be fixed. For the rear camera  54 , the fixed position is predetermined with the tailgate  36  in the closed position. For the passenger&#39;s side camera  56  and the driver&#39;s side camera  58 , the respective fixed positions are predetermined with the passenger and driver doors in their respective closed positions. 
     Hence, the cargo area camera  60  is fixedly mounted to the vehicle  10  at the rear portion of the roof of the cabin structure  28 , which is a fixed location relative to the vehicle  10 . Further, the cargo area camera  60  is fixed in a prescribed orientation relative to the vehicle  10  to capture video images of the cargo area  26 , as indicated in 1, 7 and 9. 
     A description of the image processor  50  and its operation is now provided with reference to  FIGS. 9 through 16 . As mentioned above, the image processor  50  is configured to receive the video images captured by any one and/or all of the plurality of cameras and stream them to the display  44  such that the driver of the vehicle  10  can look at the display  44  and observe the streaming video. The image processor  50  is also configured to: receive the video images captured by any one and/or all of the plurality of cameras; process each of the images thereby producing simulated overhead views of the area captured by a selected one and/or all of the plurality of cameras; and stream the simulated overhead view or views to the display  44 , overlaying the simulated views over a still image of the vehicle  10 , such that the driver of the vehicle  10  can look at the display  44  and observe streaming video of the simulated overhead view or views. 
       FIG. 9  shows a side view of the vehicle  10  showing the front camera  52 , the rear camera  54 , the driver&#39;s side camera  58  and the cargo area camera  60 . It should be understood that the passenger&#39;s side camera  56  is symmetrically placed on the passenger&#39;s side  24  of the vehicle  10 , opposite from the driver&#39;s side  22  of the vehicle  10 , and therefore captures an area along the side of the vehicle  10  opposite from the driver&#39;s side camera  58 . 
     In  FIG. 9 , the angle A F2  shows the indication of the field of view captured by the front camera  52 , the angle A R2  shows the indication of the field of view captured by the rear camera  54 , the angle ADS shows the indication of the field of view captured by the driver&#39;s side camera  58  and the angle A C2  shows the indication of the field of view captured by the cargo area camera  60 . As indicated above, the passenger&#39;s side camera  56  captures a field of view similar to that of the driver&#39;s side camera  58 . The image processor  50  receives the video images from each of the plurality of cameras and processes them to produce corresponding overhead simulated views, with a virtual or imaginary view point I, also shown in  FIG. 9 . 
     In other words, the image processor  50  includes programming that takes the video images captured within the field of view corresponding to angle A F2  by the front camera  52  and produces an overhead view V F  as shown at the right side of the display  44  in  FIGS. 13 and 14 . The overhead view V F  is generated by the image processor  50  to make it appear that the overhead view V F  is actually captured from the imaginary view point I with a field of view corresponding to the overhead angle O F  shown in  FIG. 9 . 
     Similarly, the image processor  50  takes the video images captured within the field of view corresponding to angle A R2  by the rear camera  54  and produces an overhead view V R  as shown at the right side of the display  44  in  FIG. 13 . The overhead view V R  is generated by the image processor  50  to make it appear that the overhead view V R  is actually captured from the imaginary view point I with a field of view corresponding to the overhead angle O R  shown in  FIG. 9 . 
     Further, the image processor  50  takes the video images captured within the field of view corresponding to angle ADS by the driver&#39;s side camera  58  (and similarly from the passenger&#39;s side camera  56 ) and produces an overhead view V D  (and overhead view V P ) as shown at the right side of the display  44  in  FIGS. 13 and 14 . The overhead view V D  (and overhead view V P ) is generated by the image processor  50  to make it appear that the overhead view V D  (and overhead view V P ) is actually captured from the imaginary view point I with a field of view corresponding to the overhead angle O S  shown in  FIG. 9 . 
     The image processor  50  is further configured to process video images captured by the cargo area camera  60  in any of a variety of manners. Specifically, the image processor  50  can process the video images captured by the cargo area camera  60  to generate an unaltered streaming video of a view of the cargo area  26 , as shown on the left side of the display  44  in each of  FIGS. 11-14 . The image processor  50  also processes the video images captured by the cargo area camera  60  to generate a first overhead image V C1  of the cargo area  26  and limited areas rearward and to either rearward side of the vehicle  10  with the tailgate  36  in the closed position, as shown on the right side of the display  44  in  FIG. 11 . The image processor  50  can also process the video images captured by the cargo area camera  60  to generate a second overhead image V C2  of the cargo area  26  as shown on the right side of the display  44  in  FIGS. 12 and 13 . 
     As well, the image processor  50  takes the video images captured within the field of view corresponding to angle A C2  by the cargo area camera  60  and produces an overhead view V C3  as shown on the right side of the display  44  in  FIG. 14 , which includes the cargo area  26  and areas rearward from the vehicle  10  with the tailgate  36  in the open position. The overhead views V C1 , V C2  and V C3  are generated by the image processor  50  to make it appear that the overhead view V R  is actually captured from the imaginary view point I with a field of view corresponding to the overhead angle O R  shown in  FIG. 9 . The driver of the vehicle  10  can select which of the overhead views V C1 , V C2  and V C3  are to be streamed to the display by manually operating the video control panel  46 . 
     The image processor  50  generates the various overhead views using any of a variety of algorithms. For example, in one embodiment, the image processor  50  is pre-programmed to include three dimensional coordinates relative to the vehicle body  16 , of the predetermined locations of each of the front camera  52 , the rear camera  54 , the passenger&#39;s side camera  56 , the driver&#39;s side camera  58  and the cargo area camera  60 . The planar coordinates of the field of view of each of the plurality of cameras using an assumed level or generally flat ground under the vehicle  10  as a reference relative to the vehicle  10  are also pre-programmed or stored in the image processor  50 . These three dimensional relationships are used to construct a conversion table (not shown) that is used by the image processor  50  to manipulate the captured images to generate the simulated overhead view V F , V D , V P , V R  and V C3 . 
     Since the predetermined locations of the plurality of cameras are fixed relative to the overall structure of the vehicle body  16 , the processing work done by the image processor  50  is conducted using fixed coordinates or fixed reference points relative to the vehicle body  16 . Specifically, the ground under the vehicle  10  is assumed to be flat providing a planar frame of reference and the plurality of cameras are at fixed locations relative to the vehicle body  16  and the ground under the vehicle  10 . The image processor  50  is therefore provided with the three dimensional relative distances and three dimensional relative coordinates between the ground under the vehicle  10  and each of the plurality of cameras relative to the vehicle  10 . 
     The image processor  50  carries out a coordinate conversion of each of the sets of video images captured by the front camera  52 , the rear camera  54 , the passenger&#39;s side camera  56 , the driver&#39;s side camera  58  and the cargo area camera  60  using the known predetermined locations of the plurality of cameras, the areas relative to the vehicle  10  that each camera views and the imaginary view point I, and synthesizes or generates the simulated overhead views V F , V D , V P , V R  and V C3  and superimposes them on the still image of the vehicle  10 , as shown on the right side of the display  44  in  FIG. 13 . 
     The vehicle surroundings or areas around the vehicle  10  captured by the plurality of cameras, and the cargo within the cargo area  26  are included in the video images processed by the image processor  50 . The image processor  50  can also process the video images of objects in the cargo area  26  and in the areas surrounding the vehicle  10  by using a relation between pixel addresses of the images before and after the conversion. Specifically, the image processor  50  carries out a viewpoint conversion (of the respective images of vehicle surroundings taken by the plurality of cameras) to the simulated overhead views. Then, after the viewpoint conversion, the image processor  50  joins the video images of the vehicle surroundings. With this, the image processor  50  converts the video images of the vehicle surroundings to the overhead view images (looking down the image-taking area from directly overhead at the center of the vehicle). 
     More detailed descriptions of various processes used to generate overhead simulated views can be found in, for example, U.S. Patent Application Publication No. 2010/0238051, published Sep. 23, 2010 (application Ser. No. 12/680,423), U.S. Patent Application Publication No. 2012/0069182, published Mar. 22, 2012 (application Ser. No. 13/232,146), and U.S. Pat. No. 8,243,994, issued Aug. 14, 2012 (application Ser. No. 12/298,837) all commonly assigned to Nissan Motor Co. Ltd. The disclosures of U.S. Patent Application Publication No. 2010/0238051, U.S. Patent Application Publication No. 2012/0069182, and U.S. Pat. No. 8,243,994 are incorporated herein by reference in their entirety. 
     A description of the basic operations of the image processor  50  is now provided with respect to the flowchart in  FIG. 10 . The video system  12  starts up when the ignition switch  42  is turned on. Further, if the ignition switch  42  is not on, the video system  12  is disabled or turned off. The ignition switch  42  can be a keyless switch or a switch that requires a key, depending upon the specific vehicle design. Once the ignition switch  42  is turned on, operation moves to step S 1  where the image processor  50  waits for instructions or view requests inputted by an occupant or driver of the vehicle  10 . 
     At step S 1 , a determination is made by the image processor  50  whether or not the driver or an occupant of the vehicle  10  has inputted to the video control panel  46  (a controller) a request for the video images from a specific camera to be streamed to the display  44 . If such a request has been inputted, the image processor  50  streams the selected captured video images to the left side of the display  44 . 
     Included in the processing at step S 1  is also detection based on signals from the vehicle sensors  48 , and a determination whether or not the transmission of the vehicle is set in reverse gear indicating that the driver is backing up the vehicle  10 . If the transmission is in reverse, the image processor  50  interprets that information as a request for an unaltered streaming of the area rearward of the vehicle  10  captured by the rear camera  54  (or captured by the cargo area camera  60  if the rear camera  54  is disabled). As a result, the image processor  50  streams to the left side of the display  44  unaltered video images captured by the rear camera  54  (or captured by the cargo area camera  60 ). 
     At step S 2 , the video images from the selected one of the plurality of cameras streamed by image processor  50  to the left side of the display  44 . In the depicted examples shown in  FIGS. 11-14 , the selected one of the plurality of cameras is the cargo area camera  60 . Thus, in each of the examples in  FIGS. 11-14 , the image processor  50  streams the video images from the cargo area camera  60  to left side of the display  44 . 
     From step S 2 , operations return back to the top of the flowchart in  FIG. 10 , and consequently step S 1  is repeated. If no further requests are made (if there is no change in the requested camera), operation moves to step S 3 . At step S 3 , the image processor  50  determines whether or not the video control panel  46  has received a request for a simulated overhead view of only the cargo area, and which type of simulated overhead view has been requested. If the image processor  50  determines that such a request has been made at step S 3 , then operation moves to step S 4  where the image processor  50  streams one of the overhead simulated views of the cargo area  26  to the right side of the display  44 . Specifically, the image processor  50  can stream the simulated overhead view V C1  to the right side of the display  44 , as indicated in  FIG. 11 . As shown in  FIG. 11 , the simulated overhead view V C1  includes a wide angle view of the cargo area  26  and areas rearward from the rear end  20  of the vehicle  10 . Alternatively, if requested by the driver or occupant, the image processor  50  can stream the simulated overhead view V C2  to the right side of the display  44 , as indicated in  FIG. 12 . As shown in  FIG. 12 , the simulated overhead view V C2  includes only a simulated overhead view of the cargo area  26 . 
     At step S 3 , if a request for not only the cargo area has been made, operation moves to step S 5 . At step S 5 , a determination is made as to whether or not a composite simulated overhead view has been requested. If a composite view has been requested, then operation then moves to step S 6 . At step S 6 , the image processor  50  determines whether or not the rear camera  54  is operable or not, for example, by receiving a signal from the tailgate sensor of the vehicle sensors  48 . For example, if the tailgate  36  is in the closed position ( FIG. 13 ), then the rear camera  54  is operable. If the tailgate  36  is down or in the open position ( FIG. 14 ), then the rear camera  54  is not operable. Further, if the tailgate  36  has been removed from the vehicle  10 , then the rear camera  54  is not operable. 
     Once a determination has been made at step S 6 , if the rear camera  54  is operable, operation moves to step S 7 . If the rear camera  54  is not operable, operation moves to step S 9 , described below. 
     At step S 7 , since the rear camera  54  is operable, the video images captured by the rear camera  54  are processed by the image processor  50 , along with the images captured by the front camera  52 , the passenger&#39;s side camera  56 , the driver&#39;s side camera  58  and the cargo area camera  60  and operation moves to step S 8 . At step S 8 , the image processor  50  generates the simulated overhead views V F , V R , V D , V P  and V C2 , and overlays them on a still image of the vehicle  10 , as shown at the right side of the display  44  in  FIG. 13 . 
     If at step S 6 , the image processor determines that the rear camera  54  is not operable, operation moves to step S 9 . At step S 9 , the video images captured by the front camera  52 , the passenger&#39;s side camera  56 , the driver&#39;s side camera  58  and the cargo area camera  60  are processed and the image processor  50  generates the simulated overhead views V F , V D , V P  and V C3 , and overlays them on a still image of the vehicle  10 , as shown at the right side of the display  44  in  FIG. 14 . As shown in  FIG. 14 , the simulated overhead view V C3  provides a simulated overhead view V C3  of the cargo area  26  and simulated overhead view of perceivable areas rearward of the rear end  20  of the vehicle  10 . 
     The simulated overhead view V C3  is generated in a manner consistent with the depiction in  FIG. 16  of the overhead angle O C  which corresponds to the area viewed by the cargo area camera  60  with the tail gate open. In  FIGS. 14 and 16 , the tailgate  36  is in the lowered or open position, thereby rendering the rear camera  54  inoperable. 
     The cargo area camera  60  provides many advantages. For example, since the rear camera  54  is installed to the tailgate  36 , the cargo area camera  60  can provide s substitute rear view of the vehicle  10  when the tailgate  36  is in the open position or removed completely from the vehicle  10 . Further, the cargo area camera  60  is disposed on the vehicle body  16  at a location that facilitates convenient capturing of a view of the trailer hitch receiver  38  installed to the cargo area  26  such that the driver (the vehicle operator) viewing the display  44  observes the trailer hitch receiver  38  as the vehicle moves toward a trailer hitch of a trailer T, as depicted in  FIG. 15 . The driver can view both the overhead simulated view V C3  and an unaltered view of the video images captured by the cargo area camera  60  while coupling the vehicle  10  to the trailer T. 
     Second Embodiment 
     Referring now to  FIGS. 17 and 18 , a vehicle  10 ′ depicted in accordance with a second embodiment will now be explained. In view of the similarity between the first and second embodiments, the parts of the second embodiment that are identical to the parts of the first embodiment will be given the same reference numerals as the parts of the first embodiment. Moreover, the descriptions of the parts of the second embodiment that are identical to the parts of the first embodiment may be omitted for the sake of brevity. The parts of the second embodiment that differ from the parts of the first embodiment will be indicated with a single prime (′). 
     In the second embodiment, the vehicle  10 ′ is a van that has a van structure. The vehicle  10 ′ includes a cargo area  26 ′ that defines an enclosed space  26   c ′ within the van structure of the vehicle  10 ′. As shown in  FIG. 18 , the cargo area  26 ′ includes a floor  26   a ′, side walls  26   b  and a roof (removed in  FIG. 18 ) that define the enclosed space  26   c ′ that is configured to receive cargo (not shown). The enclosed space  26   c ′ of the cargo area  26 ′ is defined between side walls  26   a ′ and above the floor  26   b ′ of the cargo area  26 ′. The cargo area  26 ′ includes a cargo area camera  60  that is basically identical to the cargo area camera  60  of the first embodiment, but is positioned to view the enclosed space  26   c ′ of the cargo area  26 ′. The vehicle  10 ′ includes a video system that is virtually identical to the video system  12  of the first embodiment as shown in  FIG. 2 , including the front camera  52 , the rear camera  54 , the passenger&#39;s side camera  56  (not shown in  FIGS. 17 and 18 ), the driver&#39;s side camera  58  and the cargo area camera  60 . In the second embodiment, the rear camera  54  is located on one of two cargo area doors of the van structure of the vehicle  10 ′. Further, as shown in  FIG. 18 , the display  44 ′ in the second embodiment shows the interior of the cargo area  26 ′ on the left side of the display  44 ′ and shows the various simulated overhead views superimposed over a still image of the van structure of the vehicle  10 ′. 
     The video system in the second embodiment operates in a manner identical to the video system  12  described with respect to  FIGS. 2 and 10 . For example, the vehicle sensors  48  depicted in  FIG. 2  can include a sensor that senses whether or not the rear cargo doors of the vehicle  10 ′ are closed. If the rear cargo doors are not closed (doors are open), the performance of the rear camera  54  may be compromised. As described above, the cargo area camera  60  can be used to capture video images of areas rearward of the vehicle  10 ′ as well as capture images of the cargo area  26 ′ when the rear cargo doors are open. This feature is the same as that described above with respect to  FIGS. 2 and 10 . 
     Since all aspects of the video system described above with respect to the first embodiment are identical and operate in the same manner as in the first embodiment, further description is omitted for the sake of brevity. 
     Third Embodiment 
     Referring now to  FIGS. 19 and 20 , a vehicle  10 ″ in accordance with a third embodiment will now be explained. In view of the similarity between the first and third embodiments, the parts of the third embodiment that are identical to the parts of the first embodiment will be given the same reference numerals as the parts of the first embodiment. Moreover, the descriptions of the parts of the third embodiment that are identical to the parts of the first embodiment may be omitted for the sake of brevity. The parts of the third embodiment that differ from the parts of the first embodiment will be indicated with a double prime (″). 
     In the third embodiment, the video system  12  is identical to that of the first embodiment, except that the cargo area camera  60  is removed and replaced with two cargo area cameras  60 ″. The cargo area cameras  60 ″ are installed to the vehicle  10 ″ at opposite rear end corners of the cabin structure and are both aimed at the cargo area  26  in order to capture video images of the cargo area. In the third embodiment, the image processor  50  is further configured to process the video images from the cargo area cameras  60 ″ such that the simulated video overhead view of the cargo area is a composite image based upon the video images captured by the cargo area cameras  60 ″. Further, in the event that one of the cargo area cameras  60 ″ is blocked by cargo or another object, the image processor  50  can still generate the simulated video overhead view of the cargo area based primarily or solely on video images from a remaining unblocked one of the cargo area cameras  60 ″. 
     The vehicles  10 ,  10 ′ and  10 ″ include various conventional components that are well known in the art. Since these conventional components are well known in the art, these structures will not be discussed or illustrated in detail herein. Rather, it will be apparent to those skilled in the art from this disclosure that the components can be any type of structure and/or programming that can be used to carry out the present invention. 
     General Interpretation of Terms 
     In understanding the scope of the present invention, the term “comprising” and its derivatives, as used herein, are intended to be open ended terms that specify the presence of the stated features, elements, components, groups, integers, and/or steps, but do not exclude the presence of other unstated features, elements, components, groups, integers and/or steps. The foregoing also applies to words having similar meanings such as the terms, “including”, “having” and their derivatives. Also, the terms “part,” “section,” “portion,” “member” or “element” when used in the singular can have the dual meaning of a single part or a plurality of parts. Also as used herein to describe the above embodiments, the following directional terms “forward”, “rearward”, “above”, “downward”, “vertical”, “horizontal”, “below” and “transverse” as well as any other similar directional terms refer to those directions of a vehicle equipped with the vehicle video system. Accordingly, these terms, as utilized to describe the present invention should be interpreted relative to a vehicle equipped with the vehicle video system. 
     The term “detect” as used herein to describe an operation or function carried out by a component, a section, a device or the like includes a component, a section, a device or the like that does not require physical detection, but rather includes determining, measuring, modeling, predicting or computing or the like to carry out the operation or function. 
     The term “configured” as used herein to describe a component, section or part of a device includes hardware and/or software that is constructed and/or programmed to carry out the desired function. 
     The terms of degree such as “substantially”, “about” and “approximately” as used herein mean a reasonable amount of deviation of the modified term such that the end result is not significantly changed. 
     While only selected embodiments have been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. For example, the size, shape, location or orientation of the various components can be changed as needed and/or desired. Components that are shown directly connected or contacting each other can have intermediate structures disposed between them. The functions of one element can be performed by two, and vice versa. The structures and functions of one embodiment can be adopted in another embodiment. It is not necessary for all advantages to be present in a particular embodiment at the same time. Every feature which is unique from the prior art, alone or in combination with other features, also should be considered a separate description of further inventions by the applicant, including the structural and/or functional concepts embodied by such features. Thus, the foregoing descriptions of the embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.