JPS58209781A - Movement of character on screen of image receiver - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] The present invention deletes one line while moving the displayed characters when the characters displayed on the cathode ray tube of a television receiver overflow, and when displaying a new line, the line movement is gradual. This invention relates to a method for moving characters on a television receiver screen.

Conventionally, when characters are printed one after another on a cathode ray tube using a word processor, etc., and the characters on the screen overflow, the first line disappears from the screen and the next line is printed and displayed. When moving one line at a time, all the lines moved instantly, which sometimes caused viewers to get confused and lose sight of what they were looking for.

The present invention has been made in view of the above points, and its purpose is to combine a digital circuit with an analog time constant circuit, and to control row movement by this time constant circuit. To provide a method for moving characters on a television receiver screen in which movement is performed slowly and the circuit is simple and can be manufactured at low cost.

Next, one embodiment of the present invention will be described with reference to the drawings.

Figure 1 shows a device for recording character signals on a magnetic tape, 1 is a television camera, 2 is a monitor television, and 3 is a device that converts the brightness of the character signal from the television camera 1 into "i" and "o". An A/D converter; 4 is a serial-parallel shift register that converts pixel signals from the A/D converter 3 into serial-parallel; 5 is a video synchronization signal generator; 6 is a clock generator;
7 is a write address counter, which is determined by the signal from the video synchronization signal generator 5 and the clock from the clock generator 6, and sends a latch pulse to the serial/parallel shift register 4 every 8 pixels, and also outputs a write address to the address switch 9. send. 8 is the output from the address switcher 9, which is the RAM that stores the 8 pixels from the serial/parallel shift register 4; 9 is the output from the write address counter 7, which stores every 8 pixels in the RAM 8; and the output from the read address counter 13. RAM switcher for reading every 8 pixels stored, 10
1 is a parallel-to-serial shift register that converts pixel signals from RAM 8 from parallel to serial, and 11 is a modulator that converts pixel "0" into one wave of, for example, 300011z, and pixel "1" into, for example, 60
Modulates into two waves of 00Hz. 1 is a recorder including a recording head; 13 is a read address counter that switches the address switch 9 according to a clock from a recording clock generator 16; 14 is a system controller; an operation panel 15;
Create a blank (unrecorded area) for 32 pixels,
・And control recording start, stop, etc. 16 is a recording clock generator that generates a clock of 300011z.

Next, to explain the operation based on the above configuration, first, the video synchronization signal generator 5 generates a signal for the television camera 1.
M) Operate synchronously with Iz, position and photograph the poem card, which has an 8-line poem written on it, while looking at monitor TV 2.

In this case, the clock generator 6 generates clocks corresponding to 256 clocks (32 x 8 lines) during horizontal scanning, and the A/D converter 3 converts the brightness of the characters into "1" and "0". 32 pixels per horizontal row, 192 columns from top to bottom, total 61
Decompose into 44 pixels in order. The decomposed pixels are sent to the serial/parallel shift register 4, where they are stored every 8 pixels, converted from serial to parallel, and sent out once to be sent to the RAM 8.

On the other hand, the write address counter 7 sends a launch pulse to the shift register every 8 pixels based on the signal from the video synchronizing signal generator 5 and the clock, and also sends the write address to the address switch 9.

Note that the pixel signals separated by a 5MHz clock have a high frequency and cannot be recorded directly on magnetic tape.
Convert to character signal of voice band frequency. The frequency of the character signal is determined by the speed at which characters are formed during playback, so for example, if one line is to be formed on the screen of a television receiver in 2 to 3 seconds, the required frequency will be 6144-)3=2048Hz to 6144+2 seconds- It will be in the range of 3072Hz. Since this is around 3000 Hz, the stable playback frequency of normal magnetic tape, clear images can be expected.

This 3000Hz clock is generated by the recording clock oscillator 16, the system controller 14 is controlled by the operation panel 15, the address switch 9 is controlled by recording start and stop operations of the recorder 12, and the read address counter 13 starts recording. The pixel signals are read from the RAM 8, converted from parallel to serial by the parallel/serial shift register 10, taken out at the timing of the clock from the recording clock generator 16, and changed. Pixel “O” in device 11 is 30
The pixel "1" modulates one wave of 00 Hz into two waves of 600011 Hz and sends them to the recorder 12. Therefore, character signals are recorded on the magnetic tape.

By the way, with the above-mentioned operation alone, pixel signals are simply sent out continuously, and in order to reproduce characters, their delimiters, line feed commands, and character clear commands must also be recorded.

Therefore, if this type of alloy, which has been commonly used in the past, was recorded with digital bits, the instruction decoding circuit would be complicated and expensive, so an interruption time (budunk in the unrecorded part) was provided in the recorded signal. Depending on the length of time, a method was adopted to decipher various instructions. That is, two-wave blanks are inserted into the recording signal at intervals of 32 pixels, blanks of 0.5 seconds are inserted as line feed commands, and blanks of 1 second or longer are inserted as RAM 8 clear commands into the recording signal. Specifically, a 32-pixel blank is generated by the system controller 14 and is created by stopping two blank waves. Further, blanks for line feed commands and clear commands are created by pressing a dedicated operation button provided on the operation panel 15 and muting the signal from the modulator 11 for a time corresponding to each time. According to this method, even if there is a dropout in the recorded signal, no practical problem occurs except that the screen is distorted or lines are changed, and the circuit is simple and the device is simple.

In turn, a character signal is recorded on the second channel of the magnetic tape in synchronization with the karaoke on the first channel.

The above is a description of the method of recording signals on a magnetic tape. Below, a method of reproducing a magnetic tape recorded in this manner will be described with reference to FIG. 2.

17 is a magnetic head, 18 is an amplifier, 19 is a character signal detection circuit, 20 is a serial/parallel shift register that converts the signal from the detection circuit 19 from serial to parallel, and 21 is for detecting a clock signal in the signal from the amplifier 18. Clock regeneration circuit, 2
2 is a 32 pixel counter for dividing every 32 pixels with the clock from the reproduction circuit 21; 23 is a line counter for dividing every line with the output from the line feed blank detection circuit 26; 24, 25, 26 is a detection circuit that detects the RAM clear blank, 2-wave blank, and line feed blank included in the signal from the amplifier 18, and 27 is a RAM that switches the write address and read address every 8 pixels.
28 is a 7th line detection counter that counts the output signal of RI from the row counter 23 and sends out an output when the 7th line is counted; 29
is the seventh line detection counter 28 and line feed blank detection circuit 26
30 is a scroll counter which sends an address signal for moving the screen line by line when the output is outputted through an AND circuit 40, and 30 is a 5M4 for video synchronization.
An oscillator that oscillates 1z, 31 is an address counter, 32
is an adder that adds the address signal generated by the scroll counter 29 and the address signal generated by the address counter 31, 33 is a RAM, and 34 is a parallel-to-serial shift register that converts the character signal read out by the RAM 33 from parallel to serial. , 35 is a high frequency modulation circuit, and 36 is a receiver. 37 is a V sync, and 38 is an H sync, and the synchronization signal generated by the ① sync and the H sync 38 is applied to the high frequency modulation circuit 35 via an OR circuit 41.

39 is a scroll controller having a circuit as detailed in FIG. 3, and when the line movement is changed in an instant,
This is to move the line slowly to prevent confusion about which line you have been reading. In other words, the line feed signal is sent to the scroll controller 3.
9 to the H sync 38, and by gradually changing the gap between the horizontal synchronizing signals.

FIG. 3 will be explained below. Ql-C4 is a transistor, Rr t RQ t Cs is a resistor and a capacitor that constitute a time constant circuit, D+ is a light emitting diode, and Z
is a light-receiving bare hand such as CdS, R3 and C2 are resistors and capacitors that constitute a time constant circuit, and M+ and M2 are one-shot multiples.

Next, to explain the operation, when the screen reaches a predetermined number of lines (7 lines in this embodiment), a low level output is sent from the 7th line detection counter 28, so the transistor Q1 turns off and waits for scrolling. Then, when the line feed blank detection circuit 26 sends out a low level output as a line feed signal, the transistor Q2 turns off, and therefore the resistor R1g Re
, the current flowing to the light emitting diode D gradually increases due to the time constant of the time constant circuit made up of the capacitor C1. Therefore, the time constant of the time constant circuit consisting of light receiving element Z and resistor R3% capacitor C2 becomes smaller, and the position of the horizontal synchronization signal shifts relatively to the front of the video signal, and the screen slowly moves to the right. Move to.

After that, when the line feed signal rises, transistor Q2
is turned on, the charge in the capacitor C1 is instantly discharged to prepare for -1st order scrolling.

Next, the operation of the circuit shown in FIG. 2 will be explained.

When a magnetic tape recorded by the above-mentioned recording apparatus shown in FIG. The amplified character signal is then divided into a character signal, a clock signal, and a blank signal. 3000Hz and 600Hz detected by character signal detection circuit 19
The character signal 0flz is serial-parallel converted by the serial-parallel shift register 20 and recorded in the RAM 33. The clock regeneration circuit 21 extracts only the clock, operates the 32-pixel counter 22 and the row counter 23, and outputs R from each.
Sends a write address signal for AM33. The signal detected by the two-wave blank detection circuit controls a 32-pixel counter 22 to divide the signal into 32-pixel units. When the line feed blank detection circuit 26 detects a blank of about 0.5 seconds, the line counter 23 is controlled to separate each line. When the RAM clear blank detection circuit 24 detects a blank for one second or more, the RAM 33 is cleared and the entire screen of the receiver 36 is erased.

On the other hand, when the seventh line is detected by the seventh line detection counter 28', a signal from the line feed blank detection circuit 26 is sent to the scroll counter 29, which sends an address signal for moving lines on the screen by - lines. . Also, the oscillator 30 oscillates 5 MHz for video synchronization, and the address counter 31
The adder 32 adds the address signal created there and the address signal created by the scroll counter 29, and sends it to the address switch 27 as a read address. Therefore, the address of the RAM 33 is controlled by switching the write address and read address every 8 pixels.

The character signal read from the RAM 33 is converted from parallel to serial in a parallel-serial shift register 34 and sent to a high frequency modulation circuit 35. In this high frequency modulation circuit 35,
V sync 37 and H sync 3 to display on the receiver 26
A synchronizing signal generated by the circuit 8 is added to perform modulation, and an image of the character signal is displayed on the receiver 36.

Conventionally, with some scrolling methods, lines change instantly when scrolling, making it confusing as to which line you were reading up until now. Therefore, in order to cause gradual scrolling, a scroll controller 39 as shown in FIG.
This allows the rows to move more slowly. After the row movement, the synchronization signal returns to its original state at the same time as the display address is shifted.

Nao: The above embodiment described magnetic tape, but
Of course, this can also be applied to audio discs.

Further, in this embodiment, a character display for karaoke has been described, but any display that displays characters sequentially like a word processor and moves line by line when the screen overflows can be used.

As described above, in a character display method in which characters are sequentially displayed using digitally processed pixel signals, when characters on the screen overflow, a line feed command signal is sent to a time constant circuit made of an analog circuit. Since we delayed the synchronization signal by gradually changing the voltage,
Line movement is gradual, so the person looking at the characters does not feel confused, and since the circuit is simple, it can be manufactured at low cost.

[Brief explanation of drawings]

The figure shows one embodiment of the apparatus used in the method of the present invention.
FIG. 2 is a block diagram of the recording device, FIG. 2 is a block diagram of the reproducing device, and FIG. 3 is a circuit diagram of the scroll control, which is a part of the same.

Claims (1)

[Claims] With digitally processed pixel signals, characters are displayed one after another, and when one line of characters is displayed, a line feed command signal is used to display the characters on the next line.When the characters on the screen overflow, the above line feed command is sent. 1. A method for moving characters on a television receiver screen, characterized in that the voltage of a synchronizing signal is gradually changed, thereby delaying a synchronizing signal so that lines are moved slowly.