JPH0619452A - Image scrolling device - Google Patents

Abstract

PURPOSE:To provide the scraping device which scrolls an image in real time through a small-capacity memory by using a line memory means. CONSTITUTION:An image data memory means 1 sends stored run-length data to a decoding means 2 from the head of an output start line set by an output start position setting means 4. The decoding means 2 decodes and sends the run-length data, sent from the image data memory means 1, to the line memory means 3. The line memory means 3 stores data of each line sent from the decoding means 2 in order and sends the data from the position set by the output start position setting means 4. The output start position setting means 4 sets the output start position according to the pixel quantity and direction of scrolling. A display means 5 displays an image with the output data from the line memory means 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image display device for displaying compressed image data on a display.

[0002]

2. Description of the Related Art In recent years, CD-I has been in the spotlight as a home multimedia device. The CD-I decodes the compressed image data and displays the image. Also, CD-I
Has a visual effect by scrolling the image.

A conventional CD-I image scroll device will be described below. FIG. 2 is a block diagram of a conventional CD-I image scroll device. In FIG. 2, 11
Is an image data memory means, 12 is a decoding means, 13 is a bitmap file memory means, 14 is an output start position setting means, and 15 is a display means.

The operation of the apparatus configured as described above will be described below. As an example, consider the case where the compressed image data is run length data.

The CD-I run length data has a run length 7 mode and a run length 3 mode. A single pixel has 1 byte (color lookup table address), and a continuous pixel of the same color has 2 bytes (color lookup). Up table address and length data) are encoded. The color lookup table address is set to 2 in the color lookup table.
Of 62,144 colors, 128 colors (in run length 7 mode) or 8 colors (in run length 3 mode) can be specified. It also indicates how many pixels or pixel pairs of the color specified by the length data continue. Then, this run length data is decoded, and a color lookup table address is assigned to each pixel to display an image.

First, the image data memory means 11 transmits the stored run length data to the decoding means 12 from the beginning of the data. The decoding means 12 decodes the run length data transmitted from the image data memory means 11, allocates a color look-up table address to each pixel, and transmits it to the bitmap file memory means 13. Bitmap file memory means 13
Sequentially stores the data transmitted from the decoding means 12, and transmits the data from the position set by the output start position setting means 14. The output start position setting means 14 sets the output start position in accordance with the scrolling pixel amount and the scroll direction. When scrolling to the right, the output start position of each line is sequentially decreased, and when scrolling to the left, the output start position of each line is sequentially increased and transmitted to the bitmap file memory means 13. Further, when scrolling up, the output start line is sequentially reduced, and when scrolling down, the output start line is sequentially increased and transmitted to the bitmap file memory means 13. Display means 1
5 displays the output data from the bit map file memory means 13 as an image. That is, run length data is once converted into a bitmap file format, and the output start position of the bitmap file is changed according to the scrolling pixel amount and the scroll direction, thereby scrolling the image of the run length data.

Here, the area of the bitmap file and C
FIG. 3 shows the relationship between the DI full-size display area (384 × 240 pixels) and the output start position. In FIG. 3, 21 is a bitmap file area and 22 is a CD-
I is a full-size display area, and 23 is an output start position.

However, in the above-mentioned conventional configuration, it takes time since the run-length data is once expanded into a bitmap file and then an image is displayed, and a large-capacity memory is required for the bitmap file. Had a point.

The present invention solves the above conventional problems and provides a scroll device for scrolling an image in real time with a small capacity memory by using a line memory means for storing image data of one line. The purpose is to

[0010]

In order to achieve this object, an image scroll device of the present invention stores image data and outputs the image data from a set output start position; Decoding means for decoding the image data output from the image data memory means, line memory means for sequentially storing the output data from the decoding means and outputting the data from a set position, pixel amount for scrolling and scrolling Output start position setting means for setting the output start position of the image data memory means and the output start position of the line memory means according to the direction, and display means for displaying the output data from the line memory means as an image. ing.

[0011]

According to the present invention, with the above structure, by using the line memory means for storing the image data of one line and the output start position setting means for setting the output start position according to the scrolling pixel amount and the scroll direction, Images can be scrolled in real time even with compressed data such as run length data in a small capacity memory.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a CD-I image scroll device according to an embodiment of the present invention. In FIG. 1, 1 is an image data memory means, 2 is a decoding means, 3
Is a line memory means, 4 is an output start position setting means, and 5 is a display means.

The operation of the apparatus configured as described above will be described below. As an example, consider the case where the compressed image data is run length data.

First, the image data memory means 1 transmits the stored run length data to the decoding means 2 from the head of the output start line set by the output start position setting means 4. The decoding means 2 decodes the run length data transmitted from the image data memory means 1, allocates a color lookup table address to each pixel, and transmits it to the line memory means 3. The line memory means 3 sequentially stores the data of one line transmitted from the decoding means 2, and transmits the data from the position set by the output start position setting means 4. The output start position setting means 4 sets the output start position in accordance with the scrolling pixel amount and the scroll direction. When scrolling to the right, the output start position of each line is sequentially decreased, and when scrolling to the left, the output start position of each line is sequentially increased and transmitted to the line memory means 3. Further, when scrolling up, the output start line is sequentially reduced, and when scrolling down, the output start line is sequentially increased and transmitted to the image data memory means 1. The display means 5 displays the output data from the line memory means 3 as an image. That is, the run length data image can be scrolled in real time by changing the decode start line of the run length data and the output start position of the data of one line according to the scrolling pixel amount and the scroll direction.

As described above, according to the present embodiment, the line memory means for storing the data of one line and the output start position setting means for setting the output start position according to the scrolling pixel amount and the scroll direction are used. The image display position can be arbitrarily set by, and the image can be scrolled in real time even with compressed data such as run length data.

[0017]

As described above, the present invention provides an image scroll device capable of scrolling an image in real time even with compressed data such as run length data in a small capacity memory (line memory means 3). You can

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a CD-I image scroll device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a conventional CD-I image scroll device.

FIG. 3 is a schematic diagram showing a relationship between a bitmap file area, a CD-I full-size display area, and an output start position.

[Explanation of symbols]

 1 image data memory means 2 decoding means 3 line memory means 4 output start position setting means 5 display means

Claims (1)

[Claims] 1. An image data memory unit that stores image data and outputs the image data from a set output start position; a decoding unit that decodes the image data output from the image data memory unit; Line memory means for sequentially storing output data from the decoding means and outputting the data from a set position, and an output start position of the image data memory means and the line memory means according to a scrolling pixel amount and a scroll direction. An image scrolling device comprising an output start position setting means for setting the output start position of the above and a display means for displaying the output data from the line memory means as an image.