JP3102876B2 - Display device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device for character / graphic information such as teletext (teletext) and videotex.

2. Description of the Related Art A standard called Level A has already been put to practical use in teletext broadcasting by the coded transmission system, and its display screen is composed of a screen of 248 dots in the horizontal direction and 204 lines (dots) in the vertical direction. The minimum unit of the coloring unit is 4 × 4 dots vertically and horizontally of the dot pattern.

For character / graphic information such as teletext, a television receiver is usually used as a display device. Therefore, two methods are used to support the above drawings.

The first method is a method of performing pseudo twice non-interlace by performing scanning twice using only one of the first and second fields.

The second is a method called pairing for displaying the same screen in both the first and second fields.

Whereas a normal television receiver forms one frame with 525 scanning lines and generates it at a cycle of 30 Hz, an EDTV called clear vision generates a frame at a cycle of 60 Hz. For this reason, when the above-described level A screen is formed on an EDTV, the same signal is normally displayed twice for two scanning lines, which causes a problem such as flicker. However, it looks like a standard television receiver. In the second method.

FIG. 3 shows an example of an oblique line when the same signal is displayed twice as described above. When performing display such as teletext or videotex, jaggedness peculiar to the digital processing screen occurs in oblique lines as shown in FIG. For this purpose, a process called smoothing (or rounding) is performed to perform dot interpolation.

The interpolation method in the conventional display device will be described below with reference to FIG. FIG. 4 shows an example of an interpolator for display in Japanese Patent Publication No. 63-59153.

In FIG. 4, FI is a field instruction signal, l1 is one display signal for an arbitrary dot of an arbitrary run-in, and CK
1 is a dot clock signal, and CK2 is a clock signal having a frequency twice that of the dot clock. Reference numeral l2 denotes a display signal obtained by shifting the display signal l1 by one dot period by the dot clock signal CK1 in the shift register 1, and l3 denotes the display signal l1 by the line memory 2.
Is a display signal delayed by one line, and 14 is a display signal obtained by shifting the display signal 13 by one dot section by the dot clock signal CK1 in the shift register 3. These six kinds of signals, the field instruction signal FI, the display signals l1, l2, l3, l4, and the dot clock signal CK1, are used as address signals of the storage means 4, and the storage means 4 changes the output pattern to change the display signal.
Output s1 and s2. The display signal s2 is shifted by one clock of the clock signal CK2 having twice the frequency of the dot clock signal CK1 by the shift register 5, and outputs a display signal s3 obtained by delaying the display signal s2 by 0.5 dot. This display signal
s3 is ORed with the display signal s1 by the OR circuit 5,
Outputs the interpolated signal s0.

When the oblique line pattern shown in FIG. 3 is interpolated by the apparatus shown in FIG. 4, the hatched portion is interpolated and displayed as shown in FIG.

In teletext broadcasting, a character display frame of 24 dots vertically and 16 dots horizontally is set for standard characters, and a coloring unit is set for a minimum of 4 × 4 dots. The coloring includes a foreground color (FG) for coloring the dot pattern and a background color (BG) for coloring other character frames.

FIG. 6 shows a conventional example of a display device in which a coloring function is added to the display interpolation device shown in FIG. In FIG. 6, reference numeral 7 denotes a block of FIG. 4, which is an interpolation signal generator. Reference numeral 8 denotes a dot pattern memory / generation unit that stores a dot pattern and performs readout generation in accordance with a synchronization signal, and generates a serial signal 11. 9 is a foreground color memory / generation unit.
The G, B, and luminance signals FR, FG, FB, and FZ are generated by matching the display timing with the serial signal l1. Reference numeral 10 denotes a background color memory / generation unit, and each of the R, G, B and luminance signals BR, B
G, BB and BZ are generated by matching the display timing with the serial signal l1. 11 indicates FR, FG, FB and FZ when the output signal s0 of the interpolation signal generator 7 is present, and BR, BG and BB when there is no output signal s0.
And BZ, and generates switching signals as SR, SG, SB and SZ. Reference numeral 12 denotes a video synthesizing unit that performs luminance conversion on the SR, SG, SB, and SZ signals and outputs the signals as R, G, and B signals.

When the display device shown in FIG. 6 is used, interpolation as shown in FIG. 8 is performed in the case of a character pattern as shown in FIG.

Problems to be Solved by the Invention In the conventional display device, as shown in FIG. 9, the dot pattern is recorded by inverting the polarity by specifying the polarity of the dot pattern, and the foreground and background colors are apparently inverted. In the case of displaying a character designated to be inverted (inverted character), interpolation is performed on parts other than the inverted character, and an interpolation process different from the original intention is performed as shown in FIG. However, there is a problem that the function for making the character easier to read has an adverse effect, and the readability of the character is significantly impaired.

In addition, in the case of the character broadcast level A, for example, in the case of the inverted character, a method of simply exchanging the foreground color and the background color by software processing and recording from the viewpoint of the flushing polarity, concealment display, and the like cannot be used.

The present invention solves the above-mentioned problem, and makes it possible to easily read the display of inverted characters at the time of polarity inversion, and furthermore, to provide a display device capable of exchanging the foreground color and the background color from the viewpoint of flashing polarity, concealed display, etc. It is intended to provide.

Means for Solving the Problems In order to solve this problem, a display device according to the present invention includes a dot pattern for representing a character figure or the like in a character display frame having an arbitrary number of dots arranged in each of the vertical and horizontal directions. A first memory for storing an inverted pattern having a dot pattern other than the character / graphic portion and a non-inverted pattern having a dot pattern only for the character / graphic portion, and displaying and reading out the dot patterns; A second memory for storing, displaying and reading out a foreground color for coloring a portion having the dot pattern in an arbitrary coloring unit which is a unit of the minimum number of dots forming a frame and colored in the same color; A third memory for storing and displaying and reading out a background color to be colored in a portion where there is no pattern, and whether the character display frame including the plurality of arbitrary coloring units is an inverted character display frame A fourth memory for storing character display frame information indicating whether or not the character display frame information is to be displayed and read out in synchronization with the dot pattern in the first memory; and a reverse memory output from the fourth memory. Inverted character section signal generating means for outputting a signal indicating an inverted character section based on the character display frame information indicating a character display frame; and a vertical and horizontal direction with respect to a dot pattern constituting the character display frame in the first memory. An interpolation circuit for selecting an arbitrary number of dots in each direction and performing interpolation processing; first switching means for switching between a dot pattern signal interpolated by the interpolation circuit and a dot pattern signal not interpolated; Second switching means for switching between a foreground color signal read from a memory and a background color signal read from the third memory, wherein the first switching means switches the reverse character When the inverted character section signal is output, the dot turn signal that is not subjected to the interpolation processing with respect to the inverted pattern is output from the first switching means and controlled by the inverted character section signal from the interval signal generating means. When there is no output of the character section signal, the dot pattern signal obtained by interpolating the non-inverted pattern is used as the first pattern signal.
In the non-inverted character section in which the interpolated dot pattern signal is output from the first switching means, the switching is performed so that the dot pattern is output from the switching means. The background color signal is output from the second switching unit except for the character / graphic portion where the foreground color signal does not have the dot pattern, and the dot pattern signal which is not subjected to the interpolation processing is output from the first switching unit. Is output, the background color signal is applied to the character / graphic portion having no dot pattern, and the foreground color signal is applied to the character / graphic portion other than the character / graphic portion having the dot pattern. The switching control of the second switching means is performed by an output signal from the first switching means so as to be output from the switching means.

Operation With the above configuration, normal smoothing is performed at the time of normal display, and smoothing processing is stopped at the time of polarity reversal, so that the reversed characters at the time of polarity reversal are prevented from becoming thin and difficult to see. Further, since the smoothing process is not performed at the time of the polarity reversal, the foreground color and the background color can be easily exchanged even in the process using the flushing polarity, the concealment display, and the like.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a display device according to a first embodiment of the present invention. Components having the same numbers as those of the conventional example shown in FIG. 6 have the same functions, and detailed description thereof will be omitted. .

In FIG. 1, reference numeral 13 denotes a character frame memory / generation unit that stores a character display frame in a dot pattern and generates a character frame signal synchronized with the dot pattern. Reference numeral 14 denotes a serial signal for absorbing a time difference between the output signal s0 of the interpolation signal generator 7 and the serial signal l1 input to the interpolation signal generator 7.
This is a delay circuit that delays l1 and outputs it as l1D. Fifteen
Is the output signal s0 of the interpolation signal generator 7 which is a smoothing processing signal when the output of the character frame memory / generator 13 is a signal indicating a normal polarity section, and And a switching unit that switches and generates a delayed output l1D of the delay circuit 14 that is a non-smoothing processed signal, and switches between an interpolated dot pattern signal and a non-interpolated dot pattern signal.

As described above, by using the output signal of the character frame memory / generation unit, the signal subjected to the interpolation processing output from the interpolation signal generation unit 7 and the signal not subjected to the interpolation processing output from the delay circuit 14 are switched and adopted. During normal display, normal smoothing is performed, and during polarity reversal, the smoothing process can be stopped. Compared to the missing pattern or missing dots or the letters appearing thinner,
It is possible to display character and graphics more effectively.

FIG. 2 is a block diagram of a display device according to a second embodiment of the present invention. Those having the same numbers as those of the conventional example shown in FIG. 6 have the same functions, and detailed description is omitted. I do.

2, the delay circuit 14 operates in the same manner as in FIG. 16 stores the attributes of flashing, concealment and inverted polarity characters, generates the presence or absence of flashing with the FLA signal, the flushing phase with the FPH signal, the presence or absence of the concealment with the CON signal, and the presence or absence of the polarity inversion character with the POL signal. It is a display attribute memory / generation unit to be performed. Reference numeral 17 denotes a POL signal of the display attribute memory / generation unit 16, which normally outputs the output signal s0 of the interpolation signal generation unit 7, which is a smoothing processing signal, and a delay circuit, which is a non-smoothing processing signal when a polarity-reversed character is generated.
It is a switching unit for switching the 14 delayed outputs l1D. Numeral 18 denotes a flushing generator for generating a flushing signal of 1 Hz in accordance with the phase of the FPH signal when the FLA signal is on. 19 is for displaying the signal from the switching unit 17 from the display attribute memory / generating unit 16
This is a gate for controlling the CON signal and a signal from the flushing generation unit 18 to generate an appropriate signal from the switching unit 11.

Normally, the display attribute signal generator of the teletext is the same as the 4 × 4 coloring unit, and each of the foreground and background memories stores 1-byte data of 2 colored blocks. However, the display attribute memory uses only 3 bits in one byte and 3 bits in total depending on the presence / absence of flushing, the presence / absence of concealment, and there is a margin of one bit per colored block.

Advantageous Effects of the Invention As described above, according to the present invention, a memory for storing a character display frame that is displayed with polarity inversion is newly set, and an interpolated signal and a non-interpolated signal are switched and displayed. When characters and graphics with polarity reversal are interpolated and displayed, the pattern to be a character is not interpolated and dots are missing or characters are no longer seen thinner, enabling more effective character and graphics display Such an excellent effect can be obtained.

Note that the present invention does not specify the interpolation method itself, but is directed to effectively displaying a character / graphic whose polarity inversion is designated. Further, although a display device performing an interlaced display is used as an embodiment of the present invention, it goes without saying that the present invention is also included in the case of a so-called double-density display device when double-speed scanning such as EDTV is performed. Absent.

[Brief description of the drawings]

FIG. 1 is a block diagram of a display device according to a first embodiment of the present invention, FIG. 2 is a block diagram of a display device according to a second embodiment of the present invention, and FIG. 4th
FIG. 5 is a block diagram of an interpolation circuit, FIG. 5 is a diagram showing an example of an interpolated display, FIG. 6 is a block diagram of a conventional display device, FIG. 7 is a diagram showing a display example, and FIG. FIG. 9 is a diagram showing a display example at the time of polarity inversion, and FIG. 10 is a diagram showing an interpolated display example at the time of polarity inversion. 1, 3, 5 ... shift register, 2 ... line memory, 4 ...
... Memory means, 6... OR circuit, 7... Interpolation signal generator, 8... Dot pattern memory and generator, 9... Foreground color memory and generator, 10. …
... Switching unit, 12 ... Video combining unit, 13 ... Character frame memory / generating unit, 14 ... Delay circuit, 15 ... Switching unit, 16 ... Display attribute memory / generating unit, 17 ... Switching unit, 19 ……Gate.

Continuation of the front page (56) References JP-A-60-202475 (JP, A) JP-A-64-23094 (JP, U) "Television Technology", July 34, July 1, 1986 Technology Publishing Co., Ltd. p.p. 27-31

Claims (1)

(57) [Claims] An inverted pattern having a dot pattern other than the character / graphic portion as a dot pattern for representing a character / graphic or the like in a character display frame having an arbitrary number of dots arranged in each of the vertical and horizontal directions and the character. A first memory for storing a non-inverted pattern having a dot pattern only in a figure portion and displaying and reading out the dot pattern; and an arbitrary unit which is a unit of the minimum number of dots forming the character display frame and colored in the same color A second memory for storing and displaying and reading out a foreground color to be colored in a portion where the dot pattern is provided in a coloring unit; and a third memory for storing and displaying and reading a background color in a portion having no dot pattern being provided in the arbitrary coloring unit. And memory for storing character display frame information indicating whether or not the character display frame composed of a plurality of the arbitrary coloring units is an inverted character display frame. A fourth memory for displaying and reading out in synchronization with a dot pattern in one memory, and a signal indicating an inverted character section based on the character display frame information indicating an inverted character display frame output from the fourth memory. An interpolating circuit for selecting an arbitrary number of dots in a vertical direction and a horizontal direction with respect to a dot pattern constituting a character display frame in the first memory, and performing an interpolation process; First switching means for switching between a dot pattern signal interpolated by an interpolation circuit and a dot pattern signal not interpolated; a foreground color signal read from the second memory;
To switch between the background color signal read from the memory of
The first switching means is controlled by an inverted character section signal from the inverted character section signal generating means, and when the inverted character section signal is output, interpolation processing is performed on the inverted pattern. An unconverted dot turn signal is output from the first switching means, and when there is no output of the inverted character section signal, a dot pattern signal interpolated for the non-inverted pattern is output from the first switching means. In the non-inverted character section where the interpolated dot pattern signal is output from the first switching means, the foreground color signal is provided for a character / graphic portion having the dot pattern. The background color signal is output from the second switching unit for portions other than the character / graphic portion having no dot pattern, and is output from the first switching unit. In an inverted character section in which a dot pattern signal not subjected to the interpolation processing is output, the background color signal is applied to a character / graphic portion having no dot pattern, and the foreground color is applied to a character / graphic portion other than the character / graphic portion having the dot pattern. A display device, wherein switching control of the second switching unit is performed by an output signal from the first switching unit so that a signal is output from the second switching unit.