JPS63266978A - Television receiver - Google Patents

Abstract

PURPOSE:To insert and display a clear character which can be easily discriminated in a simple addition circuit by making a shaped blanking pulse duration longer than a shaped character pulse duration, and providing a trimming in the vicinity of the display character. CONSTITUTION:An integrated character pulse from an integrating circuit 11 is inputted respectively to a blanking pulse shaping circuit 12 and a character pulse shaping circuit 13. Since the relation of waveform shaping threshold potentials V1, V2 of both the circuits 12, 13 shows V2>V1, the duration of the shaped blanking pulse C is longer than the duration of the shaped character pulse D. These pulses C, D are respectively supplied to a blanking circuit 14 and a character inserting circuit 15, a character superimposed video signal in which the trimming is provided in the vicinity of the character is outputted from a video signal output terminal 3.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a television receiver equipped with a character insertion circuit that inserts and displays characters in a video signal.

[Prior Art] Fig. 3 is a block diagram showing a character insertion circuit of a conventional television receiver. In the figure, (1) is a character pulse input terminal, (2) is a video signal input terminal, is the video signal output terminal, (14) is the character blanking circuit, (15
) is a character insertion circuit.

Next, the operation of F-synthetic acid will be explained.

When a character pulse as shown in FIG. 4 (A) is input from the character pulse input terminal (1), the video signal input terminal (2)
The blanking circuit (14) blanks the intermediate portion of the manually inputted video signal as shown in FIG. 4(E), resulting in a video signal as shown in FIG. 4(F). Next, a character insertion circuit (15) is inserted into the blanking part of the blanked video signal (F), which is the part where characters are to be inserted.
(G) in Figure 4 by inserting the specified characters from
A character superimposed video signal as shown in is output from the output terminal (3).

[Problem to be solved by IJI] Conventional television receivers are configured as described above, so the output level of the characters inserted by the character insertion circuit and the video signal that is the background of the characters is There were cases where the characters could not be clearly distinguished when they were the same or close to each other.

This invention was made to solve the above-mentioned problems, and an object of the present invention is to provide a television receiver that can insert and display characters that are easy to clearly distinguish by simply adding a circuit. .

[Means for Solving the Problems] A television receiver according to the present invention includes a blanking pulse shaping circuit that integrates a character pulse and generates a shaped blanking pulse and a shaped character pulse using the refined character pulse, respectively; Equipped with a character pulse shaping circuit,
The present invention is characterized in that the waveform shaping threshold potentials of these two circuits are different, so that the shaping brushing pulse width is larger than the shaping character pulse width.

[Operation] According to the present invention, the shaping threshold potential of the brushing pulse generated in the blanking pulse shaping circuit by the integral character pulse, or the shaping threshold potential of the character pulse generated in the character pulse shaping circuit. Since the width of the blanking pulse is also large, the width of the shaped blanking pulse becomes wider than the width of the shaped character pulse, and as a result, a video signal having borders before and after the displayed character is output.

[9, Embodiment of Ill] Hereinafter, an embodiment of the present invention will be described based on the drawings.

Figure f: IS1 is a block diagram showing a character insertion circuit section of a television receiver according to an embodiment of the present invention. In the figure, the same components as the conventional example shown in 3UA are given the same reference numerals. Therefore, their explanation will be omitted.

In FIG. 1, (11) is an integrating circuit that integrates the character pulse (A), (12) is a blanking pulse shaping circuit that generates a shaped blanking pulse using the above integrated character pulse, and (13) is an integral circuit that integrates the above integral character pulse. This is a character pulse shaping circuit that generates shaped character pulses using character pulses.
The waveform shaping threshold potential (Vl) of these blanking pulse shaping circuits (12) and the character pulse shaping circuit (
13), the relationship with the waveform shaping threshold potential (v2) is configured such that V2>Vl.

Next, the operation of the above configuration will be explained.

When a character pulse as shown in Figure 2 (^) is input from the character pulse input terminal (1) to the above-mentioned integrating circuit (11), the integral character as shown in Figure 2 (B) is output from this integrating circuit (11). A pulse is output. This integral character pulse (B) is input to the blanking pulse shaping circuit (12) and the character pulse shaping circuit (13), respectively, as shown in FIG.
A shaped blanking pulse as shown in C) and a shaped character pulse as shown in FIG. 2(D) are generated, respectively. At this time, the relationship between the waveform shaping threshold voltages (Vl) and (V2) of the reshaping circuits (12) and (13) is V2>Vl, and the convergence (TI ) is the width (
It will be larger than Ding 2).

On the other hand, the signal input from the video signal input terminal (2) as shown in FIG.
The above blanking circuit (
In step 14), the above-mentioned shaped blanking pulse (C) is superimposed, resulting in a video signal as shown in FIG. 2(F). Next, in the blanking part of this video signal (F),
By superimposing the above-mentioned formatted character palace (D) in the above-mentioned character insertion circuit (15), a border with a width of (ΔT = J) is created before and after the character, as shown in Fig. 2 (G). A character superimposed video signal is output from the video signal output terminal (C).

[Effects of the Invention] As described above, according to the present invention, a border can be placed before and after each character inserted into a video signal.
Even if the output level of the video signal serving as the background of the character and the inserted character are the same or similar, the character can be highlighted by the border and the character can be clearly distinguished.

Furthermore, it is only necessary to add a Mi semiconductor integrated circuit such as an integrating circuit and a pulse shaping circuit, and there is an effect that easily distinguishable characters can be inserted at low cost.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a character insertion circuit section of a television receiver according to an embodiment of the present invention, FIG. 2 is a diagram showing signal waveforms of each part of FIG. 1, and FIG. 3 is a diagram of a conventional television receiver. FIG. 4 is a block diagram of the character insertion circuit section of FIG. 4, and is a diagram showing signal waveforms of each section in FIG. (1) --- Character input terminal, (2) --- Video signal input terminal, (3) --- Video signal output terminal, (11
)... Planting circuit, (12) -... Blanking pulse shaping circuit, (13) -... Character pulse shaping circuit, (14)
)...Blanking circuit, (15)-...Character insertion circuit. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] (1) An integrating circuit that integrates a character pulse, a blanking pulse shaping circuit and a character pulse shaping circuit that generate a shaped blanking pulse and a shaped character pulse, respectively, using the integrated character pulse, and the shaped blanking pulse that is applied to the video signal. A blanking circuit that superimposes the shaped character pulse, and a character insertion circuit that superimposes the shaped character pulse on the video signal output from the blanking circuit. A television receiver characterized in that the threshold potential for waveform shaping of the circuit is higher than that of the circuit.