JP2002142199A - Data broadcasting display method and data broadcasting receiving apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a data broadcasting display method wherein clear characters which are little jaggy can be displayed when a data broadcast is received in such a way that graphics which contain figures and characters of the data broadcast are plotted so as to be displayed on a display. SOLUTION: In a front ROM 43, character fonts in various sizes which contain a character font in a size enlarged so as to match the display size of the display 24 are stored. When the characters are plotted and displayed, the size of the character fonts is calculated on the basis of the relationship between the size of a plotting plane designated by the data broadcast and the display size of the display 24. The character fonts in the size are read out from the font ROM 43. The character fonts which are read out are written (plotted) in an SDRAM 42 as they are, and they are read out from the SDRAM 42 so as to be output to a composition processing part 22. When the figures are plotted and displayed, the enlargement ratio of the figures is calculated, the figure of each object is enlarged in the enlargement ratio, it is potted on the SDRAM 42, ant it is read out from the SDRAM 42 so as to be output to the composition processing part 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to receiving a data broadcast such as a data broadcast of a BS (broadcast satellite) digital broadcast, drawing graphics including graphics and characters of the data broadcast, and displaying the graphics on a display. The present invention also relates to a method and apparatus for outputting for display.

[0002]

2. Description of the Related Art In BS digital broadcasting, graphics including graphics and characters are broadcast as data broadcasting in addition to video and audio, and the receiving side receives the data broadcasting, draws the graphics, and displays the graphics. Can be displayed above.

In this case, in the data broadcasting, the size of the drawing plane when drawing the graphics after receiving the data broadcast on the receiving side is, for example, 960 × 540 dots (960 dots in the horizontal direction, 960 dots in the vertical direction). (540 dots)
And so on.

Therefore, for example, the display size of the display is 1920 × 1080 dots (192 dots in the horizontal direction).
0 pixels, 1080 lines vertically)
A half of the size (1/4 area as an area) is a drawing plane.
Each object of graphics is drawn in an area of 0 dots, the drawn graphics are enlarged twice in the horizontal and vertical directions, and displayed on a display as an image of 1920 × 1080 dots.

[0005] However, a large-sized drawing memory is prepared on the receiving side, graphics are enlarged to 1920 × 1080 dots and drawn, and the drawn graphics are displayed on the display in the same size. It can also be displayed. Even in this case, the image displayed on the display is the same as the case where the image is drawn to a size of 960 × 540 dots and then enlarged and displayed twice.

[0006]

However, as described above, a character font read from a font memory is drawn on a drawing memory and then enlarged to a size matching the display size and displayed on a display. When the image is drawn on a drawing memory after being enlarged to a size suitable for the display size and then displayed on a display, the character font is enlarged anyway, so that a jaggy (jaggy: There is a problem that jagged characters appear and look like dirty characters.

[0007] Therefore, the present invention is to reduce jaggies,
It is designed to display beautiful characters.

[0008]

A data broadcast display method according to the present invention is a method for receiving a data broadcast, drawing graphics including graphics and characters of the data broadcast, and displaying the graphics on a display. For, after drawing the figure in the specified size, enlarge it to the size that fits the display size and display it on the display, or draw the figure to the size that fits the display size, and then draw it on the display The font generation unit generates a character font having a size matching the display size, and displays the character font on a display without enlargement.

In this case, the font generation unit reads out a character font having a size matching the display size from a font memory in which the character font having a size matching the display size is stored. It is assumed that a character font having a size matching the display size is generated.

[0010] In the data broadcast display method according to the present invention according to the above method, for a character, a font generating unit generates a character font having an enlarged size corresponding to the display size, and displays the character font without enlarging the character font. Since it is displayed on the upper side, the character font as originally designed is displayed on the display, and beautiful characters with less jaggies are displayed.

[0011]

FIG. 1 shows an embodiment of a data broadcast receiving apparatus according to the present invention, in which the data broadcast receiving apparatus is configured as a receiver having a display and a speaker.

In this example, a signal of a BS digital broadcast received by a parabolic antenna 11 is selected by a tuner 12, demodulated, and MPEG (Moving Pict).
The stream is output from the tuner 12 as a transport stream (represented by “TS” in the figure) of the Ue Experts Group system.

The transport stream is supplied to a demultiplexer 13, which outputs a video PES (Packetized Element).
target stream, audio PES, data broadcast stream, and SI / PSI signal (SI: Serv)
ice Information: Program information, PS
I: Program Specific Information
ation: program specifying information) are obtained separately.

The encoded data of the video PES from the demultiplexer 13 is decoded by the video decoder 21, and the decoded video data is synthesized with the enlarged graphics data by the synthesizing processor 22, The synthesized video data is converted into an analog video signal for display by a video processing unit 23, and the analog video signal is supplied to a display 24 such as a CRT display or a liquid crystal display, and an image is displayed on a display screen of the display 24. Is displayed.

The encoded data of the audio PES from the demultiplexer 13 is decoded by an audio decoder 25.
The decoded audio data is stored in a DAC (Digital
The signal is converted into an analog audio signal by a to-analog converter (Analog Converter) 26, the analog audio signal is amplified by an audio amplifier 27, supplied to a speaker 28, and a sound is output from the speaker 28.

SI / PSI from demultiplexer 13
The stream of the signal and the data broadcast is taken into the control unit 30.

The control unit 30 has a CPU 31. A ROM 32 in which a program to be executed by the CPU 31 is written and a RAM 34 functioning as a work area of the CPU 31 are connected to a bus 32 of the tuner 12. Multiplexer 13, video decoder 21,
It controls each part of the receiver such as the audio decoder 25.

Further, a memory 35, a graphics processing unit 41, and a font ROM 43 are connected to the bus 32, and the graphics processing unit 41 has an SDRAM (Synchronous DRA) constituting a drawing memory.
M) 42 is provided.

The memory 35 may be a volatile memory such as an SDRAM or a nonvolatile memory such as a flash memory or a hard disk. CPU 31 is a SI / PS
Necessary information of the I signal and the data broadcast stream is stored in the memory 35, read out from the memory 35, and the graphics processing unit 41 performs drawing processing and display processing of graphics and characters of the data broadcast.

The font ROM 43 stores character fonts of various sizes including a character font of an enlarged size. The font may be a vector font or the like in addition to the bitmap font.

When drawing and displaying characters, the CP
U31 calculates the size of the character font from the relationship between the size of the drawing plane specified in the data broadcast and the display size of the display 24, reads out the character font of that size from the font ROM 43, and executes a graphics processing unit. 41, the read character font is directly written (drawn) in the SDRAM 42,
42 and output to the synthesis processing unit 22.

On the other hand, in drawing and displaying a figure, the CPU 31 calculates an enlargement ratio of the figure from the relationship between the size of the drawing plane specified in the data broadcast and the display size of the display 24, and calculates the enlargement ratio. Designated to the graphics processing unit 41,
Expands the shape of each object at that magnification,
The image is drawn on the SDRAM 42, read from the SDRAM 42, and output to the synthesis processing unit 22.

FIG. 2 shows the above-described drawing processing routine performed by the CPU 31 and the graphics processing unit 41. In this drawing processing routine, it is first determined in step 51 whether or not all objects have been drawn. If not all objects have been drawn, the process proceeds from step 51 to step 52, where the object to be drawn is a character. Or a figure.

If the object to be drawn is a character, the process proceeds from step 52 to step 53,
The size of the character font is calculated, and the process proceeds to step 54, where the character font of that size is stored in the font ROM 4.
3, the process proceeds to step 55, where the read character font is written (drawn) in the SDRAM 42, and the process returns to step 51.

On the other hand, if the object to be drawn is a graphic, the flow advances from step 52 to step 56 to calculate the enlargement ratio of the graphic. Draw and return to step 51.

When it is determined in step 51 that all objects have been drawn, the drawing process is terminated and
The graphics and character data drawn on the RAM 42 are read out as enlarged graphics data from the RAM 42 and output to the synthesis processing unit 22.

In the receiver of the above-described example, for example, the display size of the display 24 is 1920 × 1080 dots (1920 pixels in the horizontal direction and 1080 lines in the vertical direction), and the size of the drawing plane specified by the data broadcasting Is 960 × 540 dots (960 dots in the horizontal direction and 540 dots in the vertical direction), as shown in FIG. 3, the image 1 of the video broadcast by the video data from the video decoder 21 has a size of 1920 × 1080 dots. And the data broadcast image 2 is 960
The size is enlarged from the size of × 540 dots to the size of 1920 × 1080 dots, that is, as shown in FIG.
The figure 2a and the character 2b in the area of 0 × 540 dots are enlarged to the figure 3a and the character 3b in the area of 1920 × 1080 dots, and are combined with the image 1 of the video broadcast and displayed.

In this case, the characters are 96
A character font 5 of a small size as shown in FIG. 5A corresponding to an area of 0 × 540 dots is stored in a font ROM.
5C corresponding to an area of 1920 × 1080 dots, instead of being doubled and read out from the SDRAM 42 and read out from the SDRAM 42 as shown by the character font 6 in FIG. ) Is read directly from the font ROM 43 and drawn on the SDRAM 42, that is, the character font 7 as originally designed is displayed on the display 24. So less jaggy,
Beautiful characters are displayed.

In the above-described example, the font generation unit is configured by the font ROM 43 storing character fonts of various sizes including a character font of an enlarged size. The font generating program may be configured by a font engine that generates a character font having a size matching the display size. Even in such a case, beautiful characters with little jaggies are displayed.

In the above-described example, the figure is drawn on a display 24 after drawing the figure in a size that matches the display size. You may make it expand on the magnitude | size which fits a size, and may display it on the display 24. FIG.

Further, in the above-described example, the data broadcast receiving apparatus is configured as a receiver including the display 24 and the speaker 28. However, the data broadcast receiving apparatus is not limited to the display and the sound output apparatus such as the speaker and the headphone. It may be configured as a separately provided set-top box in which a video signal is derived to a video output terminal and an audio signal is derived to an audio output terminal.

[0032]

As described above, according to the present invention, a character font as originally designed is displayed on a display, and a beautiful character with less jaggies is displayed.

[Brief description of the drawings]

FIG. 1 is a diagram showing one embodiment of a data broadcast receiving device of the present invention.

FIG. 2 is a diagram illustrating an example of a drawing processing routine performed by a CPU and a graphics processing unit.

FIG. 3 is a diagram showing a combination of a video broadcast image and a data broadcast image.

FIG. 4 is a diagram showing enlargement of figures and characters.

FIG. 5 is a diagram showing a comparison between the method of the present invention and the conventional method of drawing and displaying characters.

[Explanation of symbols]

Since the main parts are all described in the figure, they are omitted here.

Claims (6)

[Claims] 1. A method for receiving a data broadcast, drawing graphics including data broadcast graphics and characters, and displaying the graphics on a display, wherein the graphics are drawn in a designated size. Then, enlarge the figure to fit the display size and display it on the display, or draw the figure to fit the display size and draw it, then display it on the display, and display the characters by the font generation unit A data broadcast display method comprising generating a character font having a size matching the size and displaying the character font on a display without enlargement. 2. The data broadcast display method according to claim 1, wherein the font generation unit reads a character font having a size matching the display size from a font memory storing a character font having a size matching the display size. Data broadcasting display method to be assumed. 3. The data broadcast display method according to claim 1, wherein the font generation unit generates a character font having a size matching the display size by using a font generation program. 4. An apparatus for receiving a data broadcast, drawing graphics including graphics and characters of the data broadcast, and outputting the graphics for display, wherein the graphics are drawn in a designated size and then displayed. After the graphics are enlarged to fit the display size or the figures are drawn to fit the display size and drawn, a graphics processing unit to be output and a character font of the size that fits the display size are generated. 1. A data broadcast receiving device, comprising: a font generation unit that outputs a character font without enlarging it. 5. The data broadcast receiving apparatus according to claim 4, wherein said font generation unit reads a character font having a size matching the display size from a font memory storing a character font having a size matching the display size. Data broadcast receiving device. 6. The data broadcast receiving device according to claim 4, wherein said font generation unit generates a character font having a size matching a display size by a font generation program.