JPH0775053A - Character program recording system - Google Patents

Abstract

PURPOSE:To select whether or not to display characters in reproducing pictures without degrading picture quality at the time of VTR recording character broadcasting signals. CONSTITUTION:The character broadcasting signals are fetched from video signals 1 in a character fetching part 2, decoded in a character signal decoding part 3, divided into the number of horizontal lines required for the dot number in the vertical direction of the characters and recorded in a line memory 4. Then, they are read, '1' is outputted to a tenth H and data from the line memory 4 are outputted after an eleventh H in the horizontal scanning period of the vertical fly-back period of the video signals 1, superimposing on the video signals 1 is performed in a superimposing part 9 and recording in a VTR is performed. The reproducing signals 11 of the VTR are sliced by a slicer 12, the tenth H is monitored mn a reloading control part 15 and the data from the slicer after the following eleventh H are written in the line memory 13 at '1'. The data are read by a vertical calling counter 16 and a horizontal calling counter 17 with a synchronizing signal from a synchronizing separator part 14 as a reference and are superimposed on the required position of the video signals 11 in the superimposing part 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a character program recording system for converting a character signal by character broadcasting into a VTR (image recording device).
The present invention relates to what is recorded after being converted into a recordable signal in the vertical blanking period.

[0002]

2. Description of the Related Art Teletext signals have a bit rate of about 5.73MB
Since it is as high as PS (megabits / second), the upper limit of the recording frequency band of the signal received and demodulated by the teletext receiver is 3 ~.
It cannot be recorded with a home VTR of about 4 MHz (megahertz). Therefore, for example, a subtitle program or the like that is broadcast for the purpose of complementing a television program for the hearing impaired or the like is VT.
When recording on R, the teletext signal is decoded, converted into a signal that can be displayed in an image, and then mixed with a video signal,
That is, a method is used in which a signal for superimposing in an image is recorded and recorded. In this case, the quality of the subtitle display is deteriorated due to the narrow frequency band that can be recorded as described above. Also, since the signal is displayed as a super-displayed signal in the image, during playback, for example, the dialogue of a foreign movie is captioned. There is a problem that it is not possible to select the presence / absence.

[0003]

SUMMARY OF THE INVENTION In view of the above-mentioned problems, the present invention decodes a teletext signal into a displayable text signal and then converts the characters formed by the text signal into vertical dots forming the characters. The number of horizontal lines required for each number, and the presence / absence (white, black) of the character image at each pixel position on each horizontal line is 1
A signal represented by dots of 0 and 0, and by recording this signal in the required number of horizontal scanning periods of the required number of vertical blanking periods, the problem of unrecordable due to the high bit rate of the teletext signal, It is also possible to select whether or not to display a character image on the screen during reproduction.

[0004]

In order to solve the above problems, the present invention provides a character capturing section for capturing a character broadcasting signal multiplexed in a video signal and a character broadcasting signal for displaying the character broadcasting signal from the character capturing section. A character signal decoding unit for decoding into a character signal; a first line memory for converting pixels of the character signal from the character signal decoding unit into data of 1 and 0 and recording for each one horizontal line;
A first superimposing unit for superimposing the data of 1 and 0 of the character signal read from the line memory in a required horizontal scanning period of the vertical blanking period of the video signal, and recording the video signal from the first superimposing unit. The recording means for recording by the recording means and the video signal reproduced by the recording device are sliced at a required level, and 1 and 0 of the character signal superposed in the vertical blanking period.
And a slicer for outputting the data of 1 and 0 of the character signal from the slicer for each horizontal line.
A line memory and a second superimposing unit that superimposes 1 and 0 data of the character signal read from the second line memory by one horizontal line in a required scanning period of the reproduced video signal. The present invention provides a character program recording system configured by a reproducing means adapted to output the video signal.

[0005]

With the above construction, in the character program recording system according to the present invention, the character broadcast signal taken from the television signal by the character broadcast receiver is decoded into a required character signal. This character signal is divided into the number of horizontal lines required for the number of vertical dots forming a character, and the presence or absence (white, black) of a character image at each pixel position of each horizontal line is represented by 1 and 0 dots. A signal is generated, and this signal is superimposed in the required horizontal scanning period of the vertical blanking period, for example, by correlating 1 with a white level and 0 with a black level.
To record. Then, at the time of VTR reproduction, the data superimposed in the horizontal scanning period of the vertical blanking period is sliced and shaped at a required level to be taken out as data, and the data of each horizontal line is temporarily recorded in a line memory. 1
The data of 0 and 0 are read out and superposed on the video signal and output so as to be displayed at a required position of the image reproduced by the VTR.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a character program recording system according to the present invention will be described in detail below with reference to the drawings. 1A and 1B show an embodiment of a character program recording system according to the present invention. FIG. 1A is a block diagram of an essential part of a recording circuit, and FIG. 1B is a block diagram of an essential part of a reproducing circuit. In the figure, 1 of the recording circuit (a) is a video signal, which is obtained by receiving and demodulating a television broadcast signal. 2 is a character capturing unit, which extracts a character broadcast signal superimposed on the video signal 1 in the vertical blanking period,
Incorporate by correcting errors. 3 is a character signal decoding unit,
The character broadcasting signal from the character capturing unit 2 is decoded into a character signal for display. A line memory 4 stores data from the character signal decoding unit 3. Reference numeral 5 denotes a display rewriting latch unit which sets the display rewriting latch to "1" based on the display rewriting information which is fetched from the character broadcasting signal by the character retrieving unit 2 and decoded by the character signal decoding unit 3. Reference numeral 6 denotes a sync separation unit, which separates the sync signal from the video signal 1. Reference numeral 7 is a vertical call counter, and 8 is a horizontal call counter.
Based on the vertical and horizontal sync signals from
The signal "1" is output during the required horizontal scanning period of the vertical blanking period, for example, the period of the 10th H, and the display rewriting latch unit 5 is reset, and thereafter, the data of the line memory 4 for one horizontal line. They are sequentially read out one by one and applied to the superposition unit 9. Based on the signals from the vertical calling counter 7 and the horizontal calling counter 8, the superimposing unit 9 reads from the line memory 4 during each horizontal scanning period of, for example, 11H to 21H following the 10H of the video signal 1. The read data is sequentially superimposed and output, and input to a VTR or the like for recording.

Reference numeral 11 of the reproducing circuit (b) is a reproduced video signal, which is a video signal recorded and reproduced in the VTR by the recording circuit (a). A slicer 12 slices the video signal 11 at a required level, shapes the waveform, and outputs the digital signal. A line memory 13 is a signal from a rewrite control unit 14 described later, and records the data of 1 and 0 of the character signal superimposed on the horizontal scanning period of the vertical blanking period from the slicer 12 line by line. . Reference numeral 14 denotes a sync separation unit, which separates a sync signal from the reproduced video signal 11. The rewrite control unit 15
The 10th H of the signal from the slicer 12 is monitored, and if the display rewriting information is set (= 1), the 11th H-
The control for recording the data of each horizontal scanning period of the 21st H in the line memory 13 is performed. Reference numeral 16 is a vertical call counter, and 17 is a horizontal call counter, which sequentially reads out and superimposes the data in the line memory 13 at the timing of scanning the required subtitle display position with reference to the vertical sync signal and the horizontal sync signal from the sync separator 14. Input to section 18. The superimposing unit 18 superimposes the data from the line memory 13 on the reproduced video signal 11 and outputs the superimposed video signal 11 to a television receiver or the like.

Next, the operation of the character program recording system according to the present invention will be described. The video signal 1 received and demodulated by a teletext receiver or the like is input to the character capturing section 2, the sync separating section 6 and the superposing section 9. First, the character capturing unit 2 extracts the character broadcast signal multiplexed in the vertical blanking period of the video signal 1, performs processing such as error correction, and outputs it. This teletext signal is input to the text signal decoding unit 3 and is decoded into a text signal for display. Then, the decoded character signal is divided into the number of horizontal lines required for the number of dots in the vertical direction forming a character, and the lines are sequentially output one line at a time and written in the line memory 4. The data written in the line memory 4 is in the form of an analog signal in which white and black of each pixel forming a character are associated with 1 (white level) and 0 (black level). Also, the number of horizontal lines is, for example, when the number of vertical dots forming a character is 24, and when the character string such as subtitles is one line.
If there are 24 lines and the character string is 2 lines, it will be 48 lines. Therefore, the recording capacity of the line memory 4 is one that can record 48 lines.

After writing the character data for one screen, the display rewriting latch section 5 is set to "1". In response to the setting of the display rewriting latch unit 5, the vertical call counter 7 and the horizontal call counter 8 use the vertical synchronizing signal and the horizontal synchronizing signal from the synchronizing separating unit 6 separated from the video signal 1 as a reference, for example, As shown in FIG.
"1" is output during the 10th H period, and 10 lines of data read from the line memory 4 are output during the subsequent 11H to 21H periods, and the next 10 lines of data are output to the next vertical return. Output in the 11th to 21th periods of the line period, and the character string is 1
In the case of a row, the remaining four lines of data are output in the 11th to 14th periods of the next vertical blanking period. FIG. 2B shows an example in which the data of the horizontal line of the fifth dot from the top of the character "aiueokaki" is output in the 15th period. These data are input to the superimposing unit 9, superposed during the required period of the video signal 1, and input to the VTR,
Will be recorded. The character signal multiplexed in the vertical blanking period of the video signal 1 is deleted by the superposition.

The video signal 11 reproduced from the VTR is input to the slicer 12, the sync separation section 14 and the superposition section 18, respectively. The slicer 12 slices the reproduced video signal 11 from the VTR at a required slice level as shown in FIG. 2B, performs waveform shaping, and outputs it as 1 (white level) and 0 (black level) data. . The rewrite control unit 15 monitors the 10H signal from the slicer 12 with the sync signal from the sync separation unit 14 as a reference. If the 10H period is "1", the subsequent 11H and subsequent signals are monitored. The data from the slicer 12 is sequentially taken into the line memory 13. And the vertical call counter 16
Also, the horizontal call counter 17 separates the reproduction video signal 11 from the vertical separation signal and the horizontal synchronization signal from the sync separation unit 14 as a reference, and the scanning timing of the video signal 11 is a required display start position, for example, FIG. The data in the line memory 13 is sequentially read line by line from the time when it becomes the display position 32 in the image 31 shown in FIG. 1, is input to the superimposing unit 18, and is superimposed during the scanning period of the reproduced video signal 11 to receive the television image. Output to a machine. The character signal multiplexed in the vertical blanking period of the video signal 11 is deleted by the superposition.

It should be noted that the signal "1" for display rewriting control output in the 10th H period is composed of, for example, a required bit, and the data of this bit is used to display a subtitle character or the like, for example, as shown in FIG. The subtitle display start position 32 may be displayed. Further, in the above, the character signal has one color (black /
Although described as white), when performing color display,
The pixel data of the character signal is separated for each color of red, green and blue, and each line is recorded.
The reproduced signals of each color are subjected to matrix processing and displayed in color characters. Note that, in the above, an example of the case of a subtitle program has been described, but the present invention can be applied to a case where characters and the like are displayed on the entire screen.

[0012]

As described above, according to the character program recording system of the present invention, after decoding a character broadcast signal such as a subtitle program into a required character signal, the number of dots in the vertical direction constituting the character is changed. It is decomposed into the required number of horizontal lines, and the presence (white) and absence (black) of each pixel of each horizontal line is converted into a signal represented by 1 and 0, and this signal is required for the horizontal scanning period of the vertical blanking period. It is possible to record on a VTR for home use because it is recorded on a VTR by superimposing it on a VTR. Since a character signal with a high bit rate is recorded as an analog signal, and a vertical retrace line is produced when the VTR is reproduced. The signal superimposed on the period is taken out from the vertical blanking period by designating it to be displayed on the screen and superimposed on the video signal. Display on screen / Are those convenient that can be arbitrarily selected not shown.

[Brief description of drawings]

FIG. 1 shows an embodiment of a character program recording system according to the present invention, in which (a) is a block diagram of a main part of a recording circuit, and (b).
FIG. 3 is a block diagram of a main part of a reproducing circuit.

2A and 2B are diagrams for explaining the operation of the character program recording system according to the present invention, in which FIG. 2A is a signal waveform diagram, and FIG. 2B is a diagram showing a relationship between a character signal and dot data.

FIG. 3 is a conceptual diagram for explaining display of subtitle characters.

[Explanation of symbols]

 B Recording circuit b Reproducing circuit 1 Video signal 2 Character importing part 3 Character signal decoding part 4 Line memory 5 Display rewriting latch part 6 Sync separation part 7 Vertical call counter 8 Horizontal call counter 9 Superimposing part 11 Playback video signal 12 Slicer 13 line Memory 14 Synchronous separation unit 15 Rewrite control unit 16 Vertical call counter 17 Horizontal call counter 18 Superposition unit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location H04N 7/03 7/035 H04N 7/08 A

Claims (8)

[Claims] 1. A character capturing unit for capturing a character broadcasting signal multiplexed with a video signal, a character signal decoding unit for decoding the character broadcasting signal from the character capturing unit into a character signal for display, and a character signal decoding unit. The first line memory for converting the pixels of the character signal into the data of 1 and 0 and recording one horizontal line at a time, and the data of 1 and 0 of the character signal read from the first line memory for the vertical return of the video signal. A character program recording system comprising a first superimposing section which is superposed in a required horizontal scanning period of a line period, and a video signal from the first superimposing section is recorded by a recording device. 2. A character capturing section for capturing a character broadcasting signal multiplexed with a video signal, a character signal decoding section for decoding the character broadcasting signal from the character capturing section into a character signal for display, and a character signal decoding section. From the first line memory and the first line memory that separates the character signal of each of the colors of red, green and blue, converts the pixels of the character signal of each color into data of 1 and 0, and records one horizontal line each. 1 and 0 of read character signal
And a first superimposing section that superimposes the data of 1) in a required horizontal scanning period of the vertical blanking period of the video signal, and the video signal from the first superimposing section is recorded by a recording device. 3. The display rewriting information decoded by the character signal decoding unit is recorded in the first line memory, and the display rewriting information read from the first line memory is read by the first superimposing unit by the character signal. 3. The character program recording system according to claim 1, wherein the data of 1 and 0 are multiplexed in a horizontal scanning period different from the horizontal scanning period of the vertical blanking period. 4. The display rewriting information decoded by the character signal decoding unit is composed of required bits to represent a display position of a character, recorded in the first line memory, and read from the first line memory. Display rewriting information
3. The character program recording system according to claim 1, wherein the superimposing unit multiplexes the data of 1 and 0 of the character signal in a horizontal scanning period different from the horizontal scanning period of the vertical blanking period. 5. A character capturing section for capturing a character broadcasting signal multiplexed with a video signal, a character signal decoding section for decoding the character broadcasting signal from the character capturing section into a character signal for display, and a character signal decoding section. The first line memory for converting the pixels of the character signal into the data of 1 and 0 and recording one horizontal line at a time, and the data of 1 and 0 of the character signal read from the first line memory for the vertical return of the video signal. A first superimposing section which is superposed in a required horizontal scanning period of the line period, and a recording means for recording a video signal from the first superimposing section by a recording device;
A slicer for slicing a video signal reproduced by the recording device at a required level and outputting the data of 1 and 0 of the character signal superimposed in the vertical blanking period, and the data of 1 and 0 of the character signal from the slicer. And a second line memory for recording data of 1 and 0 of the character signal read from the second line memory for one horizontal line during a required scanning period of the reproduced video signal. And a reproducing means adapted to output a video signal from the second superimposing part. 6. A character capturing section for capturing a character broadcasting signal multiplexed with a video signal, a character signal decoding section for decoding the character broadcasting signal from the character capturing section into a character signal for display, and a character signal decoding section. From the first line memory and the first line memory that separates the character signal of each of the colors of red, green and blue, converts the pixels of the character signal of each color into data of 1 and 0, and records one horizontal line each. 1 and 0 of read character signal
Recording means for recording the video signal from the first superimposing part by a video recording device, and a first superimposing part for superimposing the data of the first superimposing part in a required horizontal scanning period of the vertical blanking period of the video signal. Slicing the video signal reproduced from the recording device at a required level and outputting the 1 and 0 data of the character signal superimposed in the vertical blanking period, and the 1 and 0 data of the character signal from the slicer. A second line memory for recording one horizontal line at a time, and 1 and 0 data of the character signals for each color of red, green and blue read from the second line memory for one horizontal in the required scanning period of the reproduced video signal. A character program recording system comprising a second superimposing section for superimposing line by line and a reproducing means for outputting a video signal from the second superimposing section. 7. The display rewriting information decoded by the character signal decoding unit is recorded in the first line memory,
The superposition unit superimposes the display rewriting information read from the first line memory in a horizontal scanning period different from the horizontal scanning period of the vertical blanking period in which the data of 1 and 0 of the character signal is superposed. On the basis of the display rewriting information, the second superimposing section superimposes 1 and 0 data of the character signal read from the second line memory by one horizontal line in a required scanning period of the reproduced video signal. The character program recording system according to claim 5 or 6, wherein 8. The display rewriting information decoded by the character signal decoding unit is composed of required bits to represent a display position of a character, recorded in the first line memory, and stored by the first superimposing unit. Display rewriting information read from the first line memory is superimposed on a horizontal scanning period different from a horizontal scanning period of a vertical blanking period in which the 1 and 0 data of the character signal is superimposed, and the display rewriting from the slicer is performed. The display position of the character signal read from the second line memory is controlled by the second superimposing unit based on the data of the bits forming the information, and one horizontal line at a time during the required scanning period of the reproduced video signal. The character program recording method according to claim 5 or 6, wherein the character program recording method is configured to be superimposed.