JP3096675U - Teletext receiver - Google Patents

Abstract

(57) [Summary] A non-interlaced interlaced video signal is added without adding a special circuit, and character information is displayed stably and easily. A character information processing unit for extracting and decoding character information from a received signal, a pseudo vertical synchronization signal generation unit for generating a pseudo vertical synchronization signal for obtaining vertical synchronization at the time of special reproduction of a video signal, A video signal processing unit 8 for performing processing of replacing a vertical synchronization signal of a video signal with a pseudo vertical synchronization signal during special reproduction. Pseudo vertical synchronization signal generator 7
Is a pseudo vertical having a shift of 0.5H (1H is the time required for one horizontal scan) with respect to the vertical synchronizing signal b of the interlaced video signal a output from the character information processing section 3 except during special reproduction. Generate a synchronization signal d. The video signal processing unit 8 replaces the vertical synchronizing signal b of the interlaced video signal a with the pseudo vertical synchronizing signal d, and outputs a non-interlaced video signal e.

Description

[Detailed description of the device]

[0001]

[Technical field to which the device belongs]

  The present invention relates to a device for receiving teletext such as teletext. , Output interlaced video signal as non-interlaced video signal The present invention relates to a receiving device that operates.

[0002]

[Prior art]

  Teletext is a teletext broadcast that is widely used mainly in Europe, and Character information of digital signals (including characters and figures) is included in radio waves of television broadcasting. It is superimposed and transmitted, and the receiver extracts the character information from the received signal and displays it on the screen. It is displayed as an image. According to the teletext, the viewers can see news, weather forecasts. You can get various information such as information, traffic information, stock prices, and if necessary, You can also print the information displayed.

[0003]   By the way, as a scanning method when displaying images on the screen, interlace and non-scan are used. It is well known that there are two methods of interlace. Figure 3 (A) shows It is a figure explaining the interlace system. This method reconstructs images by interlaced scanning. Scan every other field from P in the figure (shown by the solid line). Go to R when the first scan is completed in Q and fill the space between the previous scan lines. The second scan (shown by the broken line) is performed as described above, and when the second scan is completed in S, the process moves to P Thus, the scanning of the next frame is similarly performed. Thus, the interlace In the scan method, one screen is generated by performing two field scans. Against this Then, the non-interlaced method does not rely on interlaced scanning as shown in FIG. It is a method of drawing one scanning line at a time and performing sequential scanning. Therefore, one screen is generated.

[0004]   Interlacing is a method that is suitable for video playback and is suitable for video playback on TV. Usually adopts the interlace method. However, for interlace Since the start position P of the first scan and the start position R of the second scan are different, When displaying a still image like a character broadcast, the image is played back by the interlace method. Then, when switching from the 1st screen to the 2nd screen, the characters shake up and down on the screen. It becomes difficult to see. For this reason, the non-interlaced method should be used with teletext receivers. It is common to reproduce character information by an expression. Such non-interlace For example, a receiving device that displays an image according to a video system is described in Patent Document 1 below. There is.

[0005]

[Patent Document 1]           [Patent Document 1] JP-A-5-268539

[Patent Document 2]           Registered utility model No. 3000898

[Patent Document 3]           JP, 2001-268524, A

[0006]

[Problems to be solved by the device]

  Teletext receiver has interlace and non-interlace switching function Video signal can be played back with non-interlaced Some receivers do not have the above switching function. The only option is to play the video signal by interlacing and display it on the screen. There is a problem that the characters that are displayed are swaying up and down, making it difficult to see.

[0007]   By the way, as a device for receiving teletext, for example, a VCR equipped with a tuner (Video Cassette Recorder), video-integrated TV with a built-in VCR, etc. Conceivable. In this case, the video device may have special playback, such as fast forward or slow playback. When performing live, the vertical sync signal is disturbed and vertical blur occurs in the playback image on the screen To prevent this, a pseudo vertical sync signal is generated during special playback and Therefore, a circuit for vertical synchronization is provided. Patent Document 2 and special features In Reference 3, vertical synchronization at the time of special reproduction is established by such a pseudo vertical synchronization signal. The technology is described.

[0008]   However, in the conventional device, the pseudo vertical sync signal is not generated during special playback. It is used only for vertical synchronization. There was no idea to use this pseudo vertical sync signal for race formation.

[0009]   SUMMARY OF THE INVENTION In consideration of the above points, the present invention provides a pseudo vertical sync signal for a video device. De-interlacing the video signal without adding a special circuit It is an object to provide a character information receiving device that can display character information in a stable and easy-to-see manner. is doing.

[0010]

[Means for Solving the Problems]

  A teletext receiver according to the present invention extracts and decodes text information from a received signal. The character information processing unit and the pseudo vertical sync for vertical synchronization during special playback of video signals. The pseudo vertical sync signal generator that generates the sync signal and the vertical sync of the video signal during special playback. And a video signal processing unit that performs a process of replacing the synchronization signal with a pseudo vertical synchronization signal. In the teletext receiver, in the pseudo vertical synchronization signal generation unit, except during special reproduction, For the vertical sync signal of the interlaced video signal output from the character information processing unit To generate a pseudo vertical synchronizing signal with a predetermined time difference. This predetermined time difference is , For example, 0.5H (1H is the time required for one horizontal scan). Video The signal processing unit converts the vertical sync signal of the interlaced video signal into the pseudo vertical sync signal. Signal to convert the interlaced video signal to a non-interlaced video signal. Convert and output.

[0011]   In this way, the pseudo vertical sync signal is output at times other than during special playback. By de-interlacing the video signal using the pseudo vertical sync signal of Add a special circuit even if the receiver does not support non-interlace. It is possible to generate a non-interlaced video signal without Therefore, the character information can be stably displayed on the screen.

[0012]   The pseudo vertical synchronization signal generator is a microcomputer that performs servo control of the VCR head drum. The one provided in the black computer can be used as it is. this In this case, the time shift of the pseudo vertical sync signal can be set by software. This makes it easy to non-convert the video signal without changing the hardware. Interlacing can be realized.

[0013]

[Embodiment of device]

  FIG. 1 is a block diagram showing an embodiment of a character information receiving device according to the present invention. Here, as the character information receiving device 100, a VCR having a built-in tuner is taken as an example. I'm sick. 1 is an antenna for receiving broadcast waves, 2 is a predetermined signal from the received broadcast waves Tuner 3 which extracts the signal of the channel, 3 from the signal extracted by tuner 2 A character information processing unit for extracting and decoding teletext character information, 4 is an ordinary television This is a switch for selecting between broadcast and teletext. Change switch 4 If you switch to the solid line side, teletext is selected, if you switch to the broken line side, normal TV broadcast Is selected. The character information processing unit 3 is composed of an IC (text IC). However, it does not have the function of deinterlacing the video signal itself. .

[0014]   5 is a microcomputer for performing servo control of the VCR head drum. (Hereinafter referred to as a microcomputer), which separates the vertical sync signal from the video signal. Vertical sync signal separation unit 6 and vertical sync signal separated by the vertical sync signal separation unit 6 Based on b, the pseudo vertical sync signal generation for generating the pseudo vertical sync signal d during special reproduction is performed. It is provided with the Narubu 7. 8 is a video signal for processing for reproducing the video signal In the processing unit, the video signal from the character information processing unit 3 is an interlaced video signal. In the case of signal a, this signal is subjected to deinterlacing processing and It has a function of outputting as a tarrace video signal e. This video signal processing The unit 8 is also composed of an IC (YCA IC). In addition, the video signal processing unit 8 Also inputs the video signal of the cassette tape read by the VCR head drum. Then, normal reproduction processing is performed.

[0015]   9 is a chroma circuit for reproducing a color signal and giving it to a CRT (cathode ray tube) 11 Separates the horizontal and vertical sync signals, and based on these sync signals, CR A deflection circuit for driving the deflection coil of T11. Here, the chroma circuit 9 and the deflection Circuit 10 is shown in a separate block, but these circuits are integrated into a single IC. May be. The CRT 11 is provided on the television externally attached to the receiving device 100. However, in the case of a video-integrated television, it is installed in the receiving device 100. ing.

[0016]   Next, the non-interlace processing in the teletext receiving apparatus 100 as described above Will be described. When receiving teletext, switch the changeover switch 4 to the solid line side. Get The received signal received by the antenna 1 is transmitted via the tuner 2 to the character information processing unit 3 And the predetermined processing such as extraction and decoding of character information is performed. I mentioned above As described above, since the character information processing unit 3 does not have a deinterlacing function, The signal output from the character information processing unit 3 is the interlaced video signal a. This Video signal a includes a vertical synchronizing signal b and an image signal c (horizontal synchronization signal b). Although the term signal is also included, it is not shown in the figure because it is not directly related to the present invention. ).

[0017]   The interlaced video signal a is input to the video signal processing unit 8 and It is also input to the microcomputer 5. The microcomputer 5 receives the interlaced video signal a. When applied, the vertical sync signal separation unit 6 extracts the vertical sync signal from the video signal a. Separate b. The separated vertical synchronizing signal b is a pulse signal, and is a pseudo vertical synchronizing signal. It is given to the signal generator 7. The pseudo vertical synchronization signal generator 7 is based on the vertical synchronization signal b. Then, the pseudo vertical synchronizing signal d is generated. This pseudo vertical sync signal d is a vertical sync signal. Although it is a pulse signal similar to the signal b, as compared with the vertical synchronization signal b as shown in FIG. The signal is shifted (advanced) by 0.5H in all. Here, H is one horizontal scan The time required (the time from the start of one scan line to the start of the next scan line) is there. The number of scanning lines per screen is 525, and the number of screens transmitted per second is 30. For example, since the horizontal scanning frequency is 525 × 30 = 15750 Hz, 1H = 1/1 5750 = 63 μs, and the pseudo vertical synchronization signal d is 31.5 μs with the vertical synchronization signal b. It will shift by s.

[0018]   By the way, the pseudo vertical synchronization signal generator 7 of the microcomputer 5 originally has When performing special playback such as fast-forward playback or slow playback, the vertical sync signal may be disturbed. Generates a pseudo vertical sync signal to prevent the playback video on the screen from blurring vertically It is a circuit that causes this signal to be output only during special playback in the past. It However, according to the present invention, not only the special playback but also the microcomputer 5 Even when the video signal a is input, the vertical sync signal separated by the vertical sync signal separation unit 6 The pseudo vertical synchronization signal generator 7 outputs the pseudo vertical synchronization signal d based on the synchronization signal b. I am trying to do it. Here, the pseudo vertical sync signal generator 7 outputs the pseudo vertical sync signal. The pulse width, phase, etc. of the synchronization signal d are determined by the software incorporated in the microcomputer 5. The vertical sync signal as described above can be changed freely. To easily generate a pseudo vertical synchronizing signal d having a deviation of 0.5H with respect to the signal b. You can The pseudo vertical synchronization signal d is input to the video signal processing unit 8.

[0019]   The video signal processing unit 8 uses the interlaced video signal from the character information processing unit 3. a and the pseudo vertical synchronization signal d from the pseudo vertical synchronization signal generator 7, Performs processing to convert the terrace video signal a into a non-interlaced video signal e U That is, the image signal c of the interlaced video signal a and the pseudo vertical synchronization signal d By superimposing and, the vertical synchronization signal b of the interlaced video signal a is The pseudo vertical sync signal d having a shift of 0.5H is replaced for each field. As a result, the start position (R in FIG. 3) of the second horizontal scan is set to the first horizontal scan. The start position (P in FIG. 3) of the interlaced video signal a Is non-interlaced. The IC (Y Originally, the vertical synchronization signal of the video signal was simulated in the CA IC) during special playback. Equipped with a function to output a video signal without disturbance of vertical sync by replacing it with a direct sync signal In this invention, the interlaced video can be The signal is non-interlaced.

[0020]   The non-interlaced video signal e thus obtained is transmitted to the chroma circuit 9 and the polarized circuit. It is given to the direction circuit 10. The color signal is reproduced in the chroma circuit 9 and the reproduced signal is output. Power is applied to CRT 11. In the deflection circuit 10, the horizontal / vertical sync signal Based on this, drive currents for the horizontal and vertical deflection coils of the CRT 11 are generated. To do. In the CRT 11, this driving current causes the horizontal deflection coil and the vertical deflection coil. Drive the electron beam to deflect the electron beam emitted from the electron gun horizontally and vertically. Check and display the video of the reproduced characters on the screen. In this case, non-interlaced Since it is scanned in, it can be used only when switching screens like in the case of interlace. The vertical movements of the characters that occur are not generated, and the characters of the still image are stable on the screen of the CRT 11. Is displayed.

[0021]   Although teletext is used as an example of teletext in the above embodiment, The present invention can also be applied to teletext other than teletext.

[0022]

[Effect of device]

  As described above, according to the present invention, a video signal is generated using a pseudo vertical sync signal. No. is not compatible with non-interlaced because the issue is interlaced. Even if the receiver is a non-interlaced video receiver, no special circuit is required. It is possible to generate an audio signal, which stabilizes text information on the screen. Can be displayed.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a character information receiving device according to the present invention.

FIG. 2 is a diagram showing a vertical synchronizing signal and a pseudo vertical synchronizing signal.

FIG. 3 is a diagram illustrating an interlace system and a non-interlace system.

[Explanation of symbols]

1 antenna 2 tuner 3 Character information processing unit 4 changeover switch 5 Microcomputer 6 Vertical sync signal separation unit 7 Pseudo vertical sync signal generator 8 Video signal processor 9 Chroma circuit 10 Deflection circuit 11 CRT 100 character information receiver a Interlaced video signal b Vertical sync signal c Image signal d Pseudo vertical sync signal e Non-interlaced video signal

Claims (3)

[Scope of utility model registration request] 1. An apparatus for receiving text broadcast and displaying text information on a screen, comprising: an antenna for receiving broadcast radio waves; and a tuner for extracting a predetermined signal from the broadcast radio waves received by the antenna. A character information processing unit that extracts and decodes character information from the signal extracted by this tuner,
A microcomputer for performing servo control of a head drum of a VCR (Video Cassette Recorder) and a video signal for performing a process of replacing a vertical synchronizing signal of the video signal with a pseudo vertical synchronizing signal output from the microcomputer during special reproduction of the video signal. In a teletext receiver including a processing unit, the microcomputer is a vertical synchronization signal separation unit that separates a vertical synchronization signal from an interlaced video signal output from the character information processing unit, and other than during the special reproduction, Based on the vertical synchronization signal separated by the vertical synchronization signal separation unit, 0.5H (1H
Is a time required for one horizontal scan) and a pseudo vertical synchronization signal generation unit that generates a pseudo vertical synchronization signal with a deviation of (1 horizontal scanning), and the video signal processing unit includes an interlaced video signal from the character information processing unit, The vertical sync signal of the interlaced video signal is replaced with the pseudo vertical sync signal based on the pseudo vertical sync signal having a deviation of 0.5H from the pseudo vertical sync signal generation unit, and the interlaced video signal is replaced with the non-interlaced video signal. A teletext receiver characterized by converting into and outputting. 2. An apparatus for receiving character broadcast and displaying character information on a screen, comprising a character information processing unit for extracting and decoding character information from a received signal, and a vertical unit for special reproduction of a video signal. A character including a pseudo vertical sync signal generation unit that generates a pseudo vertical sync signal for synchronization and a video signal processing unit that performs a process of replacing the vertical sync signal of the video signal with the pseudo vertical sync signal during the special reproduction. In the broadcast receiving device, the pseudo vertical synchronization signal generation unit is a pseudo vertical synchronization unit having a predetermined time lag with respect to the vertical synchronization signal of the interlaced video signal output from the character information processing unit, except during the special reproduction. A signal is generated, the video signal processing unit replaces the vertical synchronization signal of the interlaced video signal with the pseudo vertical synchronization signal,
A teletext receiver, which converts the interlaced video signal into a non-interlaced video signal and outputs the non-interlaced video signal. 3. The teletext receiving apparatus according to claim 2, wherein the pseudo vertical synchronization signal generation unit is provided in a microcomputer that performs servo control of a head drum of a VCR, and the time of the pseudo vertical synchronization signal is set. A teletext receiver characterized in that the shift is set by software.