JP2006119544A - Image display apparatus and image display method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a memory capacity from increasing and also to prevent costs from increasing by adjusting an optimal memory bandwidth and a necessary memory amount. <P>SOLUTION: A display information storage part 101 stored display information that is control information relating an image area constituting one screen with a display form. A display data output control part 102 recognizes the display form for displaying the image by referring to the display information stored in the display information storage part 101, and controls a destination of the image output from a memory 103 or a display data producing part 104 based on a recognized display format. The display data producing part 104 processes a source image inputted from the memory 103 to produce display data based on the control of the display data output control part 102, and outputs the produced display data to the memory 103 or a display control part 105. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an image display device and an image display method, for example, an image display device and an image display method for combining and displaying a plurality of images.

With the increase in the screen size of the display device, having a RAM in the display device has become a factor in increasing the cost. Display data stored in the RAM is placed on a low-cost system memory and refreshed to the display device. Systems that drive data to display devices at rates are becoming mainstream. In such a display device, a display data generation unit transfers a plurality of image areas to the display device as one screen display data in accordance with the refresh rate of the display device. As a method for transferring display data, there is a method in which display data is once created in a memory by a display data generation unit and then transferred to a display device. In this case, since the problem that the access frequency to the memory increases occurs, it has been devised to arrange the display data in a memory that can be secured by another path (for example, Patent Document 1).
JP 2002-64697 A

  However, the conventional apparatus has a problem that the capacity of a memory that can be secured by another path increases as the display apparatus becomes larger, and the cost increases.

  The present invention has been made in view of the above points, and by adjusting the optimum memory bandwidth and the necessary memory amount, it is possible to prevent the memory capacity from increasing and to increase the cost. An object of the present invention is to provide an image display device and an image display method capable of preventing the above-described problem.

  The image display apparatus of the present invention includes a storage unit that stores image data, a display data generation unit that reads and processes the image data stored in the storage unit, and the processing unit that processes the display data generation unit. Display data output control means for selecting a display format to be displayed after image data is stored in the storage means and a display format to display the image data processed by the display data generating means as it is; and the display data And display means for displaying the image data in the display format selected by the output control means.

  The image display method of the present invention includes a step of reading and processing image data stored in a memory, a display format for displaying the processed image data after being stored in the memory, and the processed image data Selecting a display format for displaying the image data as it is, and displaying the image data in the selected display format.

  According to the present invention, the optimum memory bandwidth and the necessary amount of memory can be adjusted, thereby preventing an increase in memory capacity and suppressing an increase in cost.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Embodiment)
FIG. 1 is a block diagram showing a configuration of an image display apparatus 100 according to an embodiment of the present invention.

  The display information storage unit 101 stores display information that is control information in which image areas constituting one screen are associated with display formats. The display information stored in the display information storage unit 101 can be updated in synchronization with various source images, the update timing of the image area, the refresh timing of the image display device 100, or the like. Here, the display format is a format when an image is displayed on the display unit 106. For example, a format in which a plurality of source images are combined and displayed, a format in which the source image is enlarged and displayed, and a source image are displayed. For example, a reduced display format or a source image change format is used. Details of the display information will be described later.

  The display data output control unit 102 selects the display format of the image to be displayed by referring to the display information stored in the display information storage unit 101 using the information of the image area to be displayed, and sets the selected display format. Based on this, the image output destination of the memory 103 or the display data generation unit 104 is controlled. Specifically, the display data output control unit 102 reads the source image stored in the memory 103 and displays the display data generation unit when the display format requires the source image (image data) to be processed. The display data generation unit 104 controls the display data generation unit 104 to output the processed image from the display data generation unit 104 to the memory 103 or the display control unit 105. When the display data output control unit 102 is a display format that displays the source image as it is, the display data output control unit 102 reads the source image stored in the memory 103 and does not pass through the display data generation unit 104. Control to output to 105.

  The memory 103 stores a source image at a predetermined address, and outputs the stored source image to the display data generation unit 104 or the display control unit 105 based on the control of the display data output control unit 102. The memory 103 also stores display data, which is a processed source image input from the display data generation unit 104, at a predetermined address.

  Based on the control of the display data output control unit 102, the display data generation unit 104 processes the source image read from the memory 103 to generate display data, and outputs the generated display data to the memory 103 or the display control unit 105. To do. Here, the processing applied to the source image includes combining a plurality of source images, converting the format of the image, changing the size of the image, and the like.

  The display control unit 105 performs control so that the display data input from the display data generation unit 104 or the display data input from the memory 103 can be displayed, and outputs the display data to the display unit 106.

  The display unit 106 displays an image of display data input from the display control unit 105.

  Next, the operation of the image display apparatus 100 will be described with reference to FIG. FIG. 2 is a flowchart showing the operation of the image display apparatus 100.

  First, the image display apparatus 100 refers to the display information stored in the display information storage unit 101 by the display data output control unit 102 (step ST201). Next, the display data output control unit 102 determines from the display information whether the source image needs to be processed (step ST202).

  When the source image needs to be processed, the display data output control unit 102 controls to read the source image stored in the memory 103 and output it to the display data generation unit 104 (step ST203). Next, the image display apparatus 100 performs processing on the source image in the display data generation unit 104 (step ST204) to generate display data. Next, the image display apparatus 100 determines whether or not the generated display data is written back to the memory 103 from the display information in the display data output control unit 102 (step ST205).

  When data is written back to the memory 103, the display data output control unit 102 controls the display data to be input from the display data generation unit 104 to the memory 103, and as a result, the display data is stored in the memory 103 ( Step ST206). Next, in the image display apparatus 100, the display data output control unit 102 reads the display data, that is, the processed source image from the memory 103 at the access timing corresponding to the refresh rate (step ST207), and the display unit 106 An image of the display data is displayed (step ST208).

  In step ST205, when the data is not written back to the memory 103, the display data output control unit 102 controls the display data to be input from the display data generation unit 104 to the display control unit 105, and as a result, the display unit 106 An image of the display data is displayed (step ST208).

  On the other hand, if it is not necessary to process the source image in step ST202, the display data output control unit 102 reads the source image stored in the memory 103 (step ST209), and the read source image is the display control unit 105. As a result, the source image is displayed on the display unit 106 as an image of display data (step ST208).

  Next, a more detailed operation of the image display apparatus 100 will be described with reference to FIGS. 3 and 4. 3 and 4 are diagrams showing display information. The display information of FIG. 3 includes the area number of the image area constituting one screen, the range of the display area, the image as the source for display, information on whether to write back to the memory 103 after generating the image area, the memory Control information such as a start address and an end address on the memory 103 when the data is written back to 103 is included. The display information in FIG. 4 includes the source number used for reference, the address of the memory area where the source image exists, the information related to propagation, the information related to format conversion, and whether to write the source image to the memory 103 after various conversions. It includes control information such as information and addresses on the memory 103 when data after conversion is written back.

  First, the case of the image region 1 in FIG. 3 will be described with reference to FIGS. 3 and 4. In the case of the image area 1, the area from the display address 1 to the end address 1 is written back to the memory 103 based on the data of the source image S0 and the source image S1, and the data of the source image S0 and the source image S1 is not changed. As long as it is transferred from the memory 103 to the image area 1. In other words, in the case of the image area 1, the display data output control unit 102 controls the source image S0 and the source image S1 to be read from the memory 103 and output to the display data generation unit 104. S0 and the source image S1 are combined by the display data generation unit 104 and generated as an image of the image area 1. Thereafter, the display data output control unit 102 writes back the synthesized image as display data in the area from the display data generation unit 104 to the start address M1 to the end address M1 of the memory 103, and corresponds to the refresh rate of the image display device 100. The display data written back to the memory 103 is controlled to be output from the memory 103 to the display control unit 105 at the access timing. The source image S0 is converted each time the format conversion from YUV to RGB is performed with reference to the source number S0 in order to form the image region 1, and the source image S1 has the source number S1 in order to form the image region 1. It is read from the memory 103 every time it is referred.

  Next, the case of the image region 2 in FIG. 3 will be described with reference to FIGS. 3 and 4. In the case of the image area 2, S2 is used as a source image, and is transferred directly from the memory 103 to the display control unit 105 in accordance with the refresh rate of the display data output control unit 102 and the image display device 100. Further, the source image S <b> 2 is doubled at each change timing and written to the memory 103. That is, the source image S <b> 2 is enlarged at the display data generation unit 104 at each update timing of the source image S <b> 0 and stored as display data in the memory 103. Then, the display data output control unit 102 transfers display data from the memory 103 to the display control unit 105 in accordance with the refresh rate of the image display apparatus 100.

  As described above, according to the present embodiment, in the process until the source image is displayed, it is possible to select the case of passing through the memory 103 and the case of not passing through the memory 103. Since the necessary amount of memory can be adjusted, it is possible to prevent an increase in memory capacity and suppress an increase in cost. Further, according to the present embodiment, whether or not to store the source image to be displayed in the memory 103 after being processed can be determined simply by referring to the display information in the display information storage unit 101, so that the source image can be easily processed. Whether or not to pass through the memory 103 can be selected. In addition, according to the present embodiment, when the update cycle of the source image and the update cycle of the image area are slower than the refresh rate of the image display device 100, the data for display is created from the amount of data to be displayed. When the amount of image data is large, it is possible to reduce the amount of access to the memory 103 by passing through the memory 103, and when the display area is not enough in the memory 103 or the update timing of the source image is early The display data can be transferred to the display unit 106 without going through the memory 103. Further, according to the present embodiment, in a system that displays a plurality of image areas on a display device, the source image stored in the memory 103 for each image area is transferred to the display unit 106 as display data, or stored in the memory 103. By making it possible to select whether a plurality of stored source images are converted or combined and transferred to the display unit 106, an optimum memory bandwidth and a necessary memory amount can be adjusted.

  In this embodiment, the display information storage unit 101 and the memory 103 are provided separately. However, the present invention is not limited to this, and the display information, the source image, and the display data are stored in a single memory separately. May be. In this embodiment, the display data output control unit 102 controls the output destination with reference to the display information stored in the display information storage unit 101. However, the present invention is not limited to this, and the display information storage unit Instead of providing 101, the display data output control unit 102 may control the output destination in a predetermined order. In the present embodiment, the number of source images and image areas is not limited, and display information stored in the display information storage unit 101 can be arbitrarily set. Further, the display data generation unit 104 can be applied with an arbitrary one such as a CPU, DSP, or dedicated hardware.

  The image display apparatus and the image display method according to the present invention can prevent an increase in the memory capacity and increase the cost by adjusting the optimum memory bandwidth and the necessary memory amount. It has an effect of preventing and is useful for displaying an image.

The block diagram which shows the structure of the image display apparatus which concerns on embodiment of this invention The flowchart which shows operation | movement of the image display apparatus which concerns on embodiment of this invention. The figure which shows the display information which concerns on embodiment of this invention The figure which shows the display information which concerns on embodiment of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Image display apparatus 101 Display information storage part 102 Display data output control part 103 Memory 104 Display data generation part 105 Display control part 106 Display part

Claims (4)

Storage means for storing image data;
Display data generation means for reading out and processing the image data stored in the storage means;
Select a display format for displaying the image data processed by the display data generating means after storing it in the storage means, and a display format for displaying the image data processed by the display data generating means as they are Display data output control means,
Display means for displaying the image data in the display format selected by the display data output control means;
An image display device comprising:   2. The image according to claim 1, wherein the display data output control means selects a display format for directly displaying the image data stored in the storage means without being processed by the display data generation means. Display device. The storage means stores in advance display information that associates an image area constituting one screen with the display format,
3. The image display device according to claim 1, wherein the display data output control means selects the display format by referring to the display information using information on the image area to be displayed. Reading and processing image data stored in the memory; and
Selecting a display format to be displayed after the processed image data is stored in the memory, and a display format to display the processed image data as they are;
Displaying the image data in the selected display format;
An image display method comprising:

Images