JP4186031B2 - Navigation device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a navigation device having a moving image playback function.
[0002]
[Prior art]
In a vehicle-mounted navigation device, a map can be displayed on a display according to map data read from a DVD-ROM or the like. And according to such an electronic map, since the display area can be changed easily or continuously, it can be used more conveniently than a general book-format map book.
[0003]
In addition, if a DVD-Video is reproduced by a DVD-ROM drive device of the navigation device, a movie or the like can be watched. Alternatively, in the case of a DVD-ROM, since its capacity is large, it is possible to store moving image data in addition to map data on the DVD-ROM, and it is possible to display a moving image related to the map by this moving image data. it can.
[0004]
In the following description, DVD-ROM and DVD-Video are collectively referred to as DVD as necessary.
[0005]
[Problems to be solved by the invention]
By the way, when moving image data is read from a DVD and displayed, the moving image data is transferred from the DVD drive device to the MPEG decoder circuit by CPU or DMA transfer. For this reason, since the CPU bus line is occupied by the transfer of the moving image data during the period of transferring the moving image data, the processing capacity of the CPU is significantly reduced.
[0006]
The present invention is intended to solve such problems.
[0007]
[Means for Solving the Problems]
For this reason, in the present invention,
CPU,
A display controller circuit for displaying an image according to the supplied data on the display;
A bus line connected between the CPU and the display controller circuit;
A DVD-ROM drive device for reading data from a DVD;
A video decoder circuit;
A buffer memory circuit provided in front of the moving picture decoder circuit;
A data selector circuit provided between the DVD-ROM drive device and the bus line and the buffer memory circuit ;
When map data is read from the DVD by the DVD-ROM drive device, the read map data is supplied to the CPU through the data selector circuit and the bus line for processing.
The processing result is supplied to the display controller circuit through the bus line ,
When moving image data is read from the DVD by the DVD-ROM drive device, the read moving image data is supplied to the buffer memory circuit through the data selector circuit,
The moving image data supplied to the buffer circuit is supplied to the moving image decoder circuit and decoded,
The navigation apparatus is configured such that the decoded moving image data is supplied to the display controller circuit.
Therefore, the bus line is released from the moving image data during the period in which the moving image data is read from the DVD.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
In FIG. 1, the code | symbol 10 shows DVD and this DVD10 is DVD-ROM or DVD-Video. When the DVD 10 is a DVD-ROM, navigation map data is stored. When the DVD 10 is a DVD-Video, moving image data such as a movie encoded by the MPEG system is stored.
[0009]
Reference numeral 20 denotes a microcomputer, and the microcomputer 20 constitutes a navigation device. That is, the microcomputer 20 includes a CPU 21 that executes various programs, a ROM 22 in which these programs are written, and a RAM 23 for a work area, which are connected to each other through a bus line (system bus) 29. ing.
[0010]
Furthermore, various operation keys 24 are connected to the bus line 29 through a key interface circuit 25, and a color LCD 27, for example, is provided as a display. The LCD 27 is provided through an LCD controller circuit 26 for displaying an image on the LCD 27. It is connected to the bus line 29.
[0011]
In addition, the navigation apparatus is provided with an autonomous navigation unit, for example, a gyro 31, from which data such as the speed at which the user moves is taken out and supplied to the microcomputer 20. In addition, a vehicle speed sensor 32 that detects the traveling speed of the vehicle is provided, and an output signal thereof is supplied to the microcomputer 20.
[0012]
Furthermore, radio waves from a navigation satellite, for example, a GPS satellite, are received by the GPS antenna 33, and the received signal is supplied to a GPS unit (receiving circuit) 34. From the GPS unit 34, data such as its own position is extracted, This data is supplied to the microcomputer 20.
[0013]
Further, a DVD-ROM drive device 41 and a DVD-ROM controller circuit 42 are provided. In this case, the drive device 41 reads data from the DVD 10, and therefore, in the case of navigation, the drive device 41 is loaded with the DVD 10 containing map data and reproduces a moving image. Is set with the DVD 10 storing the moving image data.
[0014]
Further, when a command and parameter are supplied from the outside to the DVD-ROM controller circuit 42, the DVD-ROM controller circuit 42 controls the DVD-ROM drive device 41 according to the command and parameter. For example, when commands and parameters such as a read and read start sector are supplied to the DVD-ROM controller circuit 42, the DVD-ROM drive device 41 reads data from the corresponding sector of the DVD 10.
[0015]
The drive device 41 is connected to the common contact of the data selector circuit 43 through the DVD-ROM controller circuit 42, the contact on the A side of the selector circuit 43 is connected to the bus line 29, and the contact on the B side is the buffer memory circuit 44. To the MPEG decoder circuit 45, and the output of the MPEG decoder circuit 45 is supplied to the LCD controller circuit 26.
[0016]
A buffer controller circuit 46 is connected to the buffer memory circuit 44. The buffer controller circuit 46 writes data to the buffer memory circuit 44 according to the amount of data remaining in the buffer memory circuit 44, and reads data from the buffer memory circuit 44 according to a read request from the outside. It is something to execute.
[0017]
In such a configuration, when navigation is performed and when a moving image such as a movie is reproduced, they are realized as follows.
[0018]
[For navigation]
In this case, output signals from the gyro 31, the vehicle speed sensor 32, and the GPS unit 34 are processed by the CPU 21 to determine the vehicle position, and map data including the vehicle position is read from the DVD-ROM 10 through the CPU 21. .
[0019]
That is, in the case of navigation, a predetermined control signal S43 is supplied from the CPU 21 to the selector circuit 43, and the selector circuit 43 is connected to the contact on the A side as shown in FIG. Further, a control signal S42 such as a read request is supplied from the CPU 21 to the DVD-ROM controller circuit 42 to control the drive device 41, and map data is read from the DVD-ROM 10.
[0020]
Then, the map data read from the DVD-ROM 10 is transferred to the RAM 23 through the drive device 41 → the DVD-ROM controller circuit 42 → the contact on the A side of the selector circuit 43 → the data line of the bus line 29. At this time, this data transfer is executed by the CPU 21.
[0021]
Then, the map data in the RAM 23 is processed by the CPU 21 and supplied to the LCD controller circuit 26 through the bus line 29. Therefore, a map including the vehicle position is displayed on the LCD 27. Thus, when the DVD 10 is a DVD-ROM storing map data, navigation can be performed.
[0022]
[When playing movies or other movies]
In this case, the selector circuit 43 is connected to the contact on the B side by the control signal S43 from the CPU 21, contrary to FIG. The buffer controller circuit 46 determines the amount of data remaining in the buffer memory circuit 44. When the amount is less than a specified value, for example, when the buffer is not full, the buffer controller circuit 46 requests the DVD-ROM controller circuit 42 to read out the data. The control signal S42 is supplied to control the drive device 41, and the moving image data is read from the DVD-Video 10.
[0023]
Then, the moving image data read from the DVD-Video 10 is written into the buffer memory circuit 44 through the data line at the contact point on the B side of the drive device 41 → DVD-ROM controller circuit 42 → selector circuit 43.
[0024]
At this time, the request signal S45 is output from the MPEG decoder circuit 45 to the buffer controller circuit 46 along with the decoding process of the MPEG decoder circuit 45. As a result, the moving image data is read out from the buffer memory circuit 44. The moving image data is transferred to the MPEG decoder circuit 45.
[0025]
Thus, the moving image data read from the DVD-Video 10 is decoded into the original moving image data by the decoder circuit 45, and this moving image data is supplied to the LCD controller circuit 26. Therefore, the LCD 27 receives moving images such as movies. Is displayed. Thus, when the DVD 10 is a DVD-Video in which moving image data such as a movie is stored, the movie can be viewed.
[0026]
[Summary]
As described above, according to the navigation device of FIG. 1, whether the DVD 10 is a DVD-ROM storing map data or a DVD-Video storing movie data such as a movie, The DVD 10 can be properly played back.
[0027]
In this case, in particular, according to the navigation device of FIG. 1, the DVD-ROM controller circuit 42 is separated from the bus line 29 by the data selector circuit 43 when the moving image is being reproduced. Even when the bus line 29 is not occupied by the transfer of the moving image data, and therefore, the equivalent processing capability of the CPU is not reduced.
[0028]
Furthermore, since there is no reduction in the equivalent processing capacity of the CPU, when map data and related moving image data are stored in the DVD 10, when performing processing such as positioning while reproducing moving image data from the DVD 10, The processing speed does not decrease.
[0029]
In the above description, during playback of a moving image, the buffer controller circuit 46 serves as a master to control the DVD-ROM controller circuit 42 and the buffer memory circuit 44. However, as long as the reduction in processing speed does not become a problem, the CPU 21 However, the processing of the buffer controller circuit 46 can be substituted or assisted to manage the data amount of the moving image data in the buffer memory circuit 44.
[0030]
For example, when the amount of moving image data written to or read from the buffer memory circuit 44 or the remaining amount of moving image data in the buffer memory circuit 44 is detected, the CPU 21 executes this and sends a command to the buffer controller circuit 46 according to the detection result. Can be sent to the buffer controller circuit 46 to write and read out the necessary moving image data.
[0031]
Alternatively, the CPU 21 instructs the DVD-ROM controller circuit 42 as the start sector when reading moving image data from the DVD 10, and the buffer controller circuit 46 can subsequently write the read moving image data into the buffer memory circuit 44. . Further, when the moving image data remaining in the buffer memory circuit 44 becomes unnecessary due to, for example, switching from moving image playback to navigation, the CPU 21 can delete the moving image data.
[0032]
【The invention's effect】
According to the present invention, even a DVD-ROM storing map data or a DVD-Video storing moving image data such as a movie can be appropriately reproduced. Even when a moving image is being played back, the bus line is not occupied by the transfer of the moving image data. Therefore, when processing such as positioning is performed while playing back the moving image data, the processing capacity is reduced. There is nothing.
[Brief description of the drawings]
FIG. 1 is a system diagram showing an embodiment of the present invention.
[Explanation of symbols]
10 ... DVD-ROM or DVD-Video, 20 ... microcomputer, 21 ... CPU, 22 ... ROM, 23 ... RAM, 24 ... key, 25 ... key interface circuit, 26 ... LCD controller circuit, 27 ... color LCD, 29 ... Bus line, 31 ... Gyro, 32 ... Vehicle speed sensor, 33 ... GPS antenna, 34 ... GPS unit, 41 ... DVD-ROM drive device, 42 ... DVD-ROM controller circuit, 43 ... Data selector circuit, 44 ... Buffer memory circuit, 45 ... MPEG decoder circuit, 46 ... Buffer controller circuit

Claims (2)

CPU,
A display controller circuit for displaying an image according to the supplied data on the display;
A bus line connected between the CPU and the display controller circuit;
A DVD-ROM drive device for reading data from a DVD;
A video decoder circuit;
A buffer memory circuit provided in front of the moving picture decoder circuit;
A data selector circuit provided between the DVD-ROM drive device and the bus line and the buffer memory circuit ;
When map data is read from the DVD by the DVD-ROM drive device, the read map data is supplied to the CPU through the data selector circuit and the bus line for processing.
The processing result is supplied to the display controller circuit through the bus line ,
When moving image data is read from the DVD by the DVD-ROM drive device, the read moving image data is supplied to the buffer memory circuit through the data selector circuit,
The moving image data supplied to the buffer circuit is supplied to the moving image decoder circuit and decoded,
A navigation device in which the decoded moving image data is supplied to the display controller circuit. The navigation device according to claim 1, wherein
A navigation device in which the CPU manages the data amount of the moving image data in the buffer memory circuit when moving image data is read from the DVD by the DVD-ROM drive device.

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