JPH0535666Y2 - - Google Patents

Description

[Detailed explanation of the idea] (b) Industrial application fields The present invention relates to a dubbing device for character information.

(b) Prior art Japanese Patent Application Laid-Open No. 1987-78705 (G11B5/02) discloses that in a video tape recorder (VTR), a tape is wound around a rotating drum over 180 degrees, and the excess wrapped portion is removed. A configuration is shown in which character (character) information is recorded, and the character information can be dubbed.

(c) Problems to be Solved by the Invention However, in the above-mentioned conventional technology, since the winding angle of the tape is different from the usual one, it is necessary to change the mechanism. Therefore, the configuration (necessary changes) of the device becomes extensive.

Therefore, the present invention seeks to provide an after-recording apparatus with a simple configuration.

At this time, basically, the VTR can be placed in a recording state at the part where characters are to be written during the playback mode. In other words, in a line where a character is inserted, recording←→playback is switched dozens of times in 1H period (H is a horizontal period). However, in a reproducing amplifier, it takes several microseconds to several milliseconds to change from a recording state to a reproducing state and to obtain a normal output.

In other words, if you simply switch between recording and reproduction, not only will you not be able to confirm the recorded image, but you will also not be able to obtain the synchronization signal necessary to determine the insertion position of the character information to be recorded.

(d) Means for Solving the Problems The present invention provides a means for putting a rotary head in a recording state every other field in an apparatus for dubbing text information by playing back a recorded tape, and a means for putting a rotary head in a recording state for every other field, and The apparatus includes means for creating a pseudo synchronization signal based on a reproduced video signal, and means for supplying a signal of character information to be recorded to the rotary head when the rotary head is in a recording state based on the pseudo synchronization signal. be.

(e) Effect In other words, since character information is recorded in every other field, the other field is completely in the reproduction state, and although there is some flickering, the reproduced image can be visually recognized, and
Since a pseudo synchronization signal is created based on the reproduced synchronization signal and used to control the display position, character information can be recorded correctly.

(f) Examples Examples of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram of the embodiment, and FIG. 2 is a waveform diagram.

In the figure, 1 and 2 are rotary heads for Ach and Bch, 3 and 4 are R/P changeover switches for each channel, 5 and 6 are preamplifiers, 7 and 8 are recording amplifiers, and 9 is an RF switching pulse (RFSW).
10 is an FM demodulation circuit, 13 is a synchronization separation circuit, and 14 is a video processing circuit.

15 is a 378H oscillation circuit, 16 is a 1/378 frequency dividing circuit, and 17 is a character signal generation circuit. 18 is the second
This is a changeover switch for selecting the reset signal of the frequency divider circuit 16.

11 is the third changeover switch, which connects the character oscillation circuit 12 (8mm) to the recording amplifier 8 of the B channel.
Controls whether or not to supply 5.4MHz) output corresponding to the white level of the VTR.

The character signal generation circuit 17 receives the vertical synchronization signal V from the synchronization separation circuit 13, the signal synchronized with the horizontal synchronization signal H from the frequency divider circuit 16, and the RFSW signal, and generates a mute signal, an R/P mode signal, and a character signal. Outputs gate signal. Mute signal b is RFSW
A field that is synchronized with signal a and set on the recording side (in Figure 2, the side where the RFSW signal is H level)
The output signal is supplied to the video processing circuit 14 in order to mute the video signal output.

The character signal generating circuit 17 outputs a character gate signal d at a timing determined based on the vertical synchronizing signal and the output of the frequency dividing circuit 16, and during a field period in which character information is recorded (RFSWa is at H level). The displayed characters and display position are set by the user.

For example, when displaying "AA" as shown in FIG. 3, character gate signals such as those shown by e and f are output. Then, the R/P mode signal c is output in a form that covers this character gate signal d.

The character gate signal d controls the third changeover switch 11. In other words, when the character gate signal d is at H level, the 5.4MHz output is supplied to the recording amplifier 8, and the R/
The signal is applied to the B head 2 via the P changeover switch 4. At this point, dubbing of the text information is performed.

The character gate signal d is further transmitted to the video processing circuit 14.
It is also supplied to the computer and is designed to display the characters recorded on the monitor. In the embodiment, the character gate signal d is superimposed on the video signal of the field muted to the pedestal level (the field where the RFSW signal is at the H level), but when the other field (the field where the RFSW signal is at the L level) field), the character gate signal may be supplied only to the processing circuit 14.

(g) Effects of the invention As described above, according to the invention, text information, etc. can be dubbing while checking the reproduced image, so the effect is great.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a waveform diagram, and FIG. 3 is a diagram showing character display. 3, 4... Selector switch, 13... Synchronous separation circuit, 15... Oscillator, 16... Frequency divider, 17...
Character signal generation circuit.

Claims (1)

[Scope of utility model registration request] In an apparatus for dubbing character information by reproducing a recorded tape, means for setting a rotary head to a recording state every other field, and means for creating a pseudo synchronization signal based on a reproduced video signal from the rotary head in a reproducing state. and a means for supplying a signal of character information based on the pseudo synchronization signal when the rotary head is in a recording state.