Abstract:
Information display device and method for a vehicle are provided. The information display device for a vehicle includes: a camera unit that generates and outputs image information on the rear side of the vehicle; a main processing unit that performs predetermined functions including an image processing function on the image information; and a sub processing unit that processes the image information and displays the processed image information on a display unit until the main processing unit ends a booting operation, when the image information is output from the camera unit in a state where the main processing unit is performing the booting operation. Accordingly, it is possible to guarantee the safety at the time of backing a vehicle up even when the main processing unit is performing the booting operation and to make a driver not wait until the main processing unit ends the booting operation for the purpose of acquiring necessary information.

Description:
CROSS REFERENCE 
     This application is based on and claims priority under 35 USC 119 from Korean Patent Application No. 10-2010-0079601, filed on Aug. 18, 2010. 
     BACKGROUND 
     1. Field of the Invention 
     The present invention relates to vehicle information display device and method for a vehicle. 
     2. Description of the Related Art 
     In general, an information display device performing a car audio function, a route guiding function, and the like is mounted on a vehicle so as to comfort a driver&#39;s tedium or to help a driver drive the vehicle. The information display device further has a broadcast service function such as terrestrial DMB and a multimedia function such as video reproduction. 
     Recently, the information display device further has had a function of displaying an image supplied from a rear camera on a display unit when the vehicle backward moves in cooperation with the rear camera. 
     Such an information display device includes single processing means (for example, a processor). 
     However, since the information display device including the single processing means performs various complex functions, the booting time of the information display device increases to be equal to or greater than about 7 seconds. Accordingly, there is a problem in that the information display function can be performed normally after the booting is ended. 
     In consideration that a driver generally puts the transmission into reverse to backward drive the vehicle just after starting up the vehicle, such a problem may cause inconvenience that the driver waits until the booting of the information display device is ended, or may cause a dangerous situation that the driver starts driving the vehicle in a state where safety is not guaranteed for the rear side of the vehicle. 
     The above-mentioned related art is technical information which is thought out to make the invention or is learned by the inventor in the course of making the invention, but cannot be thus said to be technical information known to the public before filing the invention. 
     SUMMARY 
     An advantage of some aspects of the invention is that it provides information display device and method for a vehicle in which a sub processing unit processes an image input from a rear camera and displays the processed image on a display unit until a main processing unit ends a booting operation, when a vehicle enters a back-up mode in a state where the main processing unit is performing the booting operation. 
     Another advantage of some aspects of the invention is that it provides information display device and method for a vehicle which can guarantee safety at the time of backing a vehicle up even when a main processing unit is performing a booting operation and which can make a driver not wait until the main processing unit ends the booting operation for the purpose of acquiring necessary information. 
     Other advantages of the invention will be apparently understood from the following description. 
     According to an aspect of the invention, there is provided a information display device for a vehicle including: a camera unit that generates and outputs image information on the rear side of the vehicle; a main processing unit that performs predetermined functions including an image processing function on the image information; and a sub processing unit that processes the image information and displays the processed image information on a display unit until the main processing unit ends a booting operation, when the image information is output from the camera unit in a state where the main processing unit is performing the booting operation. 
     The main processing unit may activate firmware or an ROTS (Real-time Operation System) so as to allow the sub processing unit to process the image information and then loads OS (Operating System) data read from a storage medium into a memory so as to perform the booting operation, when a boot loader is activated. 
     The sub processing unit may include a sensor that receives a gear shift event for allowing a vehicle to enter a back-up mode, and may check whether the main processing unit ends the booting operation when the gear shift event is received. 
     The sensor may be one of a GPIO (General Purpose Input/Output) pin and an external interrupt unit. 
     The camera unit may be activated when a gear shift event for allowing a vehicle to enter a back-up mode is received. 
     The sub processing unit may determine whether the main processing unit is performing the booting operation on the basis of information stored in a storage space to be shared with the main processing unit. 
     The sub processing unit may determine whether the main processing unit is performing the booting operation on the basis of a signal received from the main processing unit through a signal line connected to the main processing unit. 
     The main processing unit and the sub processing unit may be embodied as a single chip or individual chips. 
     The information display device may further include: a first switching unit that sets an input path for inputting the image information output from the camera unit to one of the main processing unit and the sub processing unit; and a second switching unit that sets an output path for inputting display data output from one of the main processing unit and the sub processing unit to the display unit. 
     The sub processing unit may control the first and second switches to input the image information and to output the display data when the image information is output from the camera unit in the state where the main processing unit is performing the booting operation. 
     According to another aspect of the invention, there is provided an information display method carried out by a sub processing unit of an information display device, including the steps of receiving a gear shift event for allowing a vehicle to enter a back-up mode; determining whether a main processing unit is performing a booting operation; and processing image information output from a camera unit and outputting the processed image information to a display unit until the main processing unit ends the booting operation when it is determined that the main processing unit is performing the booting operation. 
     The main processing unit may activate firmware or an ROTS (Real-time Operation System) so as to allow the sub processing unit to process the image information and then loads OS (Operating System) data read from a storage medium into a memory so as to perform the booting operation, when a boot loader is activated. 
     The sub processing unit may include a sensor that receives a gear shift event, and may check whether the main processing unit ends the booting operation when the gear shift event is received. 
     The sensor may be one of a GPIO (General Purpose Input/Output) pin and an external interrupt unit. 
     The camera unit may generate and output image information on the rear side of a vehicle, and may be activated when a gear shift event for allowing the vehicle to enter a back-up mode is received. 
     The sub processing unit may determine whether the main processing unit is performing the booting operation on the basis of information stored in a storage space to be shared with the main processing unit. 
     The sub processing unit may determine whether the main processing unit is performing the booting operation on the basis of a signal received from the main processing unit through a signal line connected to the main processing unit. 
     The information display device may further include: a first switching unit that sets an input path for inputting the image information output from the camera unit to one of the main processing unit and the sub processing unit; and a second switching unit that sets an output path for inputting display data output from one of the main processing unit and the sub processing unit to the display unit. Here, the sub processing unit may control the first and second switches to input the image information and to output the display data when the image information is output from the camera unit in the state where the main processing unit is performing the booting operation. 
     According to the above-mentioned configurations, it is possible to allow a sub processing unit to process an image input from a rear camera and to display the processed image on a display unit until a main processing unit ends a booting operation, when a vehicle enters a back-up mode in a state where the main processing unit is performing the booting operation. 
     It is also possible to guarantee safety at the time of backing a vehicle up even when a main processing unit is performing a booting operation and a driver does not have to wait until the main processing unit ends the booting operation for the purpose of acquiring necessary information. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a diagram schematically illustrating the configuration of an information display device according to the related art. 
         FIG. 2  is a diagram schematically illustrating the configuration of an information display device according to an embodiment of the invention. 
         FIGS. 3 and 4  are diagrams schematically illustrating the flow of operations in an information display device according to an embodiment of the invention. 
         FIG. 5  is a flowchart illustrating the flow of processes of an information display device according to an embodiment of the invention. 
     
    
    
     DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     The invention can be variously modified in various forms and specific embodiments will be described and shown in the drawings. However, the embodiments are not intended to limit the invention, but it should be understood that the invention includes all the modifications, equivalents, and replacements belonging to the spirit and the technical scope of the invention. When it is determined that detailed description of known techniques associated with the invention makes the gist of the invention obscure, the detailed description will be omitted. 
     Terms such as “first” and “second” can be used to describe various elements, but the elements are not limited to the terms. The terms are used only to distinguish one element from another element. 
     The terms used in the following description are used to merely describe specific embodiments, but are not intended to limit the invention. An expression of the singular number includes an expression of the plural number, so long as it is clearly read differently. The terms such as “include” and “have” are intended to indicate that features, numbers, steps, operations, elements, components, or combinations thereof used in the following description exist and it should be thus understood that the possibility of existence or addition of one or more different features, numbers, steps, operations, elements, components, or combinations thereof is not excluded. 
     Terms, “unit”, “-er(-or)”, “module”, and the like, described in the specification mean a unit for performing at least one function or operation and can be embodied by hardware, by software, or by a combination of hardware and software. 
     So long as they are not defined differently, all the terms used herein, which include technical or scientific terms, have the same meanings as generally understood by those skilled in the art. The terms defined in dictionaries used in general should be analyzed to have the same meaning as in the contexts of the related art, but the terms should not be analyzed ideal or excessively formal as long as they are not clearly defined. 
     The exemplary embodiments of the invention will be described below in detail with reference to the accompanying drawings. 
       FIG. 1  is a diagram schematically illustrating the configuration of an information display device according to the related art. 
     Referring to  FIG. 1 , the information display device includes a camera unit  110 , an image processing unit  120 , and a display unit  130 . Although not shown, the information display device may further include a memory unit that stores image data processed by the image processing unit  120 . 
     The camera unit  110  is mounted on a vehicle so as to monitor the rear side of the vehicle and generates and outputs an image of the rear side of the vehicle. The camera unit  110  can be embodied by a camera device including a lens and an image processor and is turned on when a gear shift for allowing a vehicle to enter a back-up mode is sensed. The camera unit  110  may further include an A/D converter that converts analog image information into digital image information. 
     The image processing unit  120  includes a camera signal input unit  140 , a processor  145 , and a display data output unit  150 . 
     The camera signal input unit  140  provides the processor  145  with image information input from the camera unit  110 . 
     The processor  145  senses an external interrupt associated with the gear shift. When the external interrupt is associated with the gear shift for allowing the vehicle to enter the back-up mode, the processor  145  processes the image information input from the camera unit  110 , converts the processed image information into display data to be displayed on the display unit  130 , and outputs the display data to the display data output unit  150 . 
     The processor  145  may sense the external interrupt through a GPIO (General Purpose Input/Output) or may include an external interrupt unit for sensing the external interrupt. The configuration of the processor  145  for sensing the external interrupt is obvious to those skilled in the art and thus description thereof is not made. 
     The processor  145  performs an image process (for example, one or more of lens shading compensation, noise filtering, global contrast enhancement, auto white balance, encoding, and decoding) on the image information input from the camera unit  110 . 
     The processor  145  may be embodied as a chip including an image signal processor and/or a multimedia processor. 
     The display data output unit  150  provides the display data output from the processor  145  to the display unit  130  so as to display the display data on a display screen. 
     As described above, the image processing unit  120  can allow a driver to recognize the rear situation of the vehicle by repeatedly performing the procedure of processing the image information input from the camera unit  110  and updating a screen image to be displayed on the display unit  130 . 
     In this way, the information display device according to the related art includes only the single processor  145 . The booting time of the information display device has increased to perform various complex functions and the rear monitoring function desired by the driver is not normally performed in the course of booting. 
       FIG. 2  is a diagram schematically illustrating the configuration of an information display device according to an embodiment of the invention. 
     Referring to  FIG. 2 , the information display device includes a camera unit  210 , an image processing unit  220 , and a display unit  230 . Although not shown, the information display device may further include a memory unit that stores image data processed by the image processing unit  220 . 
     The camera unit  210  is mounted on a vehicle so as to monitor the rear side of the vehicle and generates and outputs image information on the rear side of the vehicle. The camera unit  210  can be embodied by a camera device including a lens and an image processor. The camera unit  210  may further include an A/D converter that converts analog image information into digital image information. 
     The image processing unit  220  includes a camera signal input unit  240 , a main processing unit  245 , a sub processing unit  250 , and a display data output unit  255 . 
     The camera signal input unit  240  provides the main processing unit  245  or the sub processing unit  250  with the image information input from the camera unit  210 . That is, in a back-up mode, the image information is supplied to the main processing unit  245  when the main processing unit ends a booting operation, and the image information is supplied to the sub processing unit  250  when the main processing unit  245  is performing the booting operation. 
     The main processing unit  245  is a processing unit that performs a function designated to be performed by the image processing unit  220  in a state where the booting of the information display device is normally ended. The sub processing unit  250  is a processing unit that performs a process (for example, one or more of lens shading compensation, noise filtering, global contrast enhancement, auto white balance, encoding, and decoding) on the image information input from the camera unit  210  and displays the processed image information on the display unit  230 . 
     The main processing unit  245  and the sub processing unit  250  may each include an image signal processor and/or a multimedia processor, and may be embodied as individual chips or as a single chip. When the main processing unit  245  and the sub processing unit  250  are embodied as individual chips, a camera signal input unit and a display data output unit may be included in each chip. 
     When the information display device is turned on, the main processing unit  245  starts performing the booting operation. In the booting operation of the main processing unit  245 , a boot loader is first activated, firmware or an ROTS (Real-time Operation System) is activated to allow the sub processing unit  250  to process the image information, OS (Operating System) data is read from a storage medium and is loaded into a memory, and then the actual booting operation is started. By this booting operation, the sub processing unit  250  can be switched to a state where the image information input from the camera unit  210  can be processed even when the main processing unit  245  is performing the booting operation. 
     The sub processing unit  250  includes an external interrupt unit that senses an external interrupt. Since the external interrupt unit is disposed in the sub processing unit  250 , the sub processing unit  250  can sense the external interrupt and perform necessary processes without interruption or help of the main processing unit  245 . The external interrupt may be sensed by the GPIO as described above. When the external interrupt associated with a gear shift for allowing the vehicle to enter the back-up mode is sensed, the sub processing unit  250  checks the state of the main processing unit  245 , and starts processing and outputting the image information input from the camera unit  210  when the main processing unit  245  is performing the booting operation. 
     When the main processing unit  245  and the sub processing unit  250  are embodied as a single chip, a storage space (not shown) used for the main processing unit  245  and the sub processing unit  250  to share information is disposed in the chip. One or more of information on a current state, information on processes, and setting and control information on other elements (for example, one or more of the camera signal input unit, the display data output unit, and the first and second switching units) is stored in the storage space. 
     The sub processing unit  250  recognizes the current state of the main processing unit  245  with reference to the storage space. The main processing unit  245  checks the processing state on the basis of the information stored in the shared storage space so as to perform the process, which is performed by the sub processing unit  250 , and control the other elements so as to input and output the image information, after the booting operation is ended. 
     However, when the main processing unit  245  and the sub processing unit  250  are embodied as individual chips and the shared storage space is not present, the main processing unit  245  notifies the sub processing unit of the end of the booting operation by the GPIO, receives and processes the image information by controlling the other elements (such as the first and second switching units), and outputs the processed information to the display unit  230 . 
     As described above, the image processing unit  220  according to this embodiment includes the main processing unit  245  and the sub processing unit  250  and can normally perform the rear side monitoring function by the use of the sub processing unit  250  switched to a state where it can normally perform processes even before the main processing unit  245  ends the booting operation. 
       FIGS. 3 and 4  are diagrams schematically illustrating the flow of operations in an information display device according to an embodiment of the invention.  FIGS. 3 and 4 , the main processing unit  245  and the sub processing unit  250  are embodied as individual chips, respectively. 
     Referring to  FIGS. 3 and 4 , the information display device includes a camera unit  210 , a first image processing unit  220   a  second image processing unit  220   b , a display unit  230 , a first switching unit  310 , and a second switching unit  320 . Although not shown, the information display device may further include a memory unit for storing image data processed by the image processing units  220   a  and  220   b.    
     The first switching unit  310  inputs image information input from the camera unit  210  to the first image processing unit  220   a  and the second image processing unit  220   b.    
     For example, the first switching unit  310  may set a default path (see  FIG. 3 ) so as to input the image information to the first image processing unit  220 ; may switch an input path of the image information to the second image processing unit  220   b  (see  FIG. 4 ) under the control of the sub processing unit  250  having received an external interrupt on the gear shift for allowing the vehicle to enter the back-up mode during the booting operation of the main processing unit  245 , or may switch the input path of the image information to the first image processing unit  220   a  again under the control of the main processing unit  245  having ended the booting operation. The path control of the main processing unit  245  and the sub processing unit  250  may be carried out, for example, using the GPIO. 
     The first image processing unit  220   a  and the second image processing unit  220   b  may include the main processing unit  245  and the sub processing unit  250 , respectively, as shown in the drawing. The first and second image processing units  220   a  and  220   b  may further include the camera signal input unit  240  and the display data output unit  250  described above. 
     The main processing unit  245  and the sub processing unit  250  can be connected to each other through the GPIO or an interrupt line. The main processing unit  245  outputs a high signal or a low signal to the sub processing unit  250  through the GPIO depending on whether it is performing the booting operation. The sub processing unit  250  senses the current state of the main processing unit  245  on the basis of the signal. 
     Accordingly, the sub processing unit  250  processes and outputs the image information input from the camera unit  210  only when the main processing unit  245  is performing the booting operation in the back-up mode of the vehicle, and controls the first and second switching units  310  and  320  to allow the main processing unit  245  to process and output the image information when the main processing unit  245  ends the booting operation. 
     In this case, the main processing unit  245  and the sub processing unit  250  output display data which is obtained by processing the image information input through the switching of the first switching unit  310 . 
     In addition, the main processing unit  245  having ended the booting operation may access a storage space, which stores processing information, in the sub processing unit  250  and sharing the processing information using a host port interface (HPI) method. In this way, when the HPI method is used, the booting state information of the main processing unit  245  may be supplied to the sub processing unit  250  through the HPI. 
     The main processing unit  245  or the sub processing unit  250  controls the second switching unit  320  to output the display data obtained by processing the image information to the display unit  230  for the purpose of the rear monitoring function. 
       FIG. 5  is a flowchart illustrating the flow of an information display method according to an embodiment of the invention. 
     Referring to  FIG. 5 , the sub processing unit  250  receives a gear shift event for allowing a vehicle to enter a back-up mode through the GPIO or the external interrupt unit in step  510 . 
     In step  520 , the sub processing unit  250  determines whether the main processing unit  245  is performing the booting operation, on the basis of the information stored in the storage space shared with the main processing unit  245  or on the basis of the signal supplied from the main processing unit  245  through the GPIO or using the HPI method. 
     When the main processing unit  245  ends the booting operation, the main processing unit  245  processes the image information input from the camera unit  210  and outputs the processed image information to the display unit  230  in step  530 . 
     On the contrary, when the main processing unit  245  is performing the booting operation, the sub processing unit  250  processes the image information input from the camera unit  210  and outputs the processed image information to the display unit in step  540 . At this time, the switching operation is carried out so that the input path of the image information from the camera unit  210  and the output path to the display unit  230  pass through the sub processing unit  250 . 
     When the vehicle is in the back-up mode (that is, when the image information is continuously being input from the camera unit  210 ), the sub processing unit  250  determines whether the main processing unit  245  ends the booting operation in step  550 . 
     When it is determined that the main processing unit  245  does not end the booting operation, the sub processing unit  250  processes and outputs the image information input from the camera unit  210  again in step  540 . 
     On the contrary, when it is determined that the main processing unit  245  ends the booting operation, the main processing unit  245  processes and outputs the image information input from the camera unit  210  in step  530 . At this time, the switching operation is carried out so that the input path of the image information from the camera unit  210  and the output path to the display unit  230  pass through the main processing unit  245 . 
     The above-mentioned vehicle information display method may be put into practice in the form of a time-series automated procedure by a software program built in the vehicle information display device. Codes and code segments of the program will be easily obtained by programmers skilled in the art. The program can be stored in a computer-readable recording medium and can be read and executed by a computer to embody the above-mentioned method. Examples of the recording medium include a magnetic recording medium, an optical recording medium, and a carrier wave medium. 
     While the invention has been described with reference to the exemplary embodiments, it will be understood by those skilled in the art that the invention can be modified and changed in various forms without departing from the spirit and scope of the invention described in the appended claims.