JPH0292077A - Video signal display device - Google Patents

Abstract

PURPOSE:To utilize the screen of the tube effectively even if the aspect ratio of a display section and a video signal differs by compressing a time base of the video signal with a prescribed compression ratio for each prescribed period, inserting 1 signal of additional information in an idle time band on the time base caused by compression and expanding the scanning line amplitude with a magnification ratio being a reciprocal of the compression ratio. CONSTITUTION:A signal is written in a built-in line memory by using a write clock CK 1 outputted from a timing signal generating circuit 4 and outputted to a terminal H of a switch circuit 6 through the readout by using a readout clock CK 2 in a frequency higher than that of the clock CK 1. A video signal generating circuit 6 inputs additional information 200 and outputs it to a terminal L of the switch circuit 6 as a video signal able to be displayed on a cathode ray tube 7. A horizontal scanning signal SH fed to the cathode ray tube 7 is a signal in which the scan lateral width is magnified by 5/4. The switch circuit 6 is thrown to the position of the terminal L for the additional information period by a switching signal S and the video signal outputted from the video signal generating circuit 5 is outputted to the cathode ray tube 7.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a video signal display device suitable for use when the aspect ratio of a video signal display unit such as a cathode ray tube and the video signal is different.

(Prior Art) In recent years, wide-aspect television broadcasting that is different from current television broadcasting, and television receivers and the like compatible with this wide-aspect television broadcasting have been proposed. The screen aspect ratio of current television receivers is 4:3, but it is proposed that wide aspect television receivers have an aspect ratio of 5:3 or 16:9 to increase the sense of realism. has been done. When considering the compatibility between this wide aspect television receiver and conventional television receivers, for example, if a video signal with a conventional aspect ratio is displayed on the cathode ray tube of a wide aspect television receiver, , as shown in FIG. 4(A), an empty space (shaded area) is created on the right, left, or both sides of the screen. Conversely, when a wide aspect ratio video signal is displayed on the cathode ray tube of a conventional television receiver, there is empty space (diagonal lines) at the top, bottom, or top and bottom of the screen, as shown in Figure 4 (B).
Can be done. In this case, wide aspect ratio video signals are displayed all at once so that there is no empty space above or below a conventional cathode ray tube, and either or both of the left and right portions of the video signal protrude from the screen. There is a method that does not do this, but this has the disadvantage that part of the video information is lost. In addition, the above figures 4 (A) and (B
) has the disadvantage that the CRT surface is not used effectively, resulting in empty space and waste. In addition, video signals include teletext signals, character code subtitles (closed captions) displayed by a video disc player, channels displayed on a television receiver, audio tape, etc., or a video tape recorder (closed caption system). Since additional information display information such as display of timer recording settings of VTR) is included, these additional information are also displayed within the narrowed actual display range of the video signal, making the display small and cluttered and unsightly. However, there was a drawback that part of the screen that was the background was erased.

(Problems to be Solved by the Invention) As mentioned above, it is possible to display a video signal with a conventional aspect ratio on a cathode ray tube of a wide aspect television receiver, or to display a video signal with a conventional aspect ratio on a CRT of a wide aspect television receiver. However, when displaying a video signal from a computer, there is a problem that empty space is created and the surface of the cathode ray tube is not used effectively.

Furthermore, when additional information is displayed together with the video signal, the additional information also appears small and the screen becomes cluttered. Therefore, the present invention eliminates the above-mentioned drawbacks, and even when the aspect ratios of the display section and the video signal are different, the present invention provides an image that can effectively utilize the screen surface of the display section without creating any empty space on the display surface of the display section. The purpose is to provide a signal display device.

[Structure of the Invention] (Means for Solving the Problems) The present invention displays the video signal on a display section having an aspect ratio different from that of the video signal, and also displays an additional information signal input separately. In the video signal display device, a time axis compression means compresses the time axis of the video signal at a predetermined compression ratio every predetermined period, and a time axis generated by compressing the time axis of the video signal by the time axis compression means. a signal insertion means for inserting the signal of the additional information into the above vacant time period; and a signal insertion means for expanding the horizontal scanning of the screen of the video signal compressed by the time axis compression means at an expansion ratio consisting of the reciprocal of the compression ratio. It has a configuration that includes a scanning means that expands the time axis by scanning.

(Function) In the video signal display device of the present invention, the time axis compression means compresses the time axis of the video signal having an aspect ratio different from that of the display section at a predetermined compression ratio every predetermined period, and compresses the time axis of the video signal at a predetermined compression ratio. Output to the display section. The signal insertion means compresses the time axis of the video signal by the time axis compression means, inserts a signal of additional information input separately into an empty time zone on the time axis, and outputs the signal to the display section. The scanning means enlarges the scanning line width in the time axis direction compressed by the time axis compression means of the display section at an enlargement ratio that is a reciprocal of the compression ratio and scans the display unit.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 is a circuit diagram showing an embodiment of the video signal display device of the present invention. However, this example is an example of a circuit for displaying a video signal having a conventional aspect ratio on a cathode ray tube of a wide aspect television receiver. 1 is an image compression circuit that compresses a standard aspect ratio video signal 100 into 475 pixels in the time direction every horizontal scanning line period, and 2 is a video signal @10.
3 is a PLL circuit that creates a clock GK from the horizontal synchronous signal H, 4 is a clock CK1, CK2, CK3 and a display switching signal based on the clock CK. A timing signal generation circuit that generates S, 5 is additional information 2 to be input.
00, a video signal generation circuit that generates a corresponding video signal, and 6 a switch that switches the video signal from the image compression circuit 1 side or the additional information video generation circuit 5 side based on the display switching signal S and outputs it to the cathode ray tube 7 side. The circuit 7 is a wide aspect ratio cathode ray tube that displays the video signal as an image on the screen.

Next, the operation of this embodiment will be explained. First, the image compression circuit 1 receives a video signal 10 with a standard aspect ratio (4:3).
0 is input. The image compression circuit 1 receives an input video signal 100
After digitizing it, it is written into the built-in line memory using the write clock CKI output from the timing signal generation circuit 4. Thereafter, the video signal written in the line memory is read out using the read clock CK2 outputted from the timing signal generation circuit 4 and outputted to the terminal H of the switch circuit 6. At this time, by increasing the frequency of the read clock CK2 with respect to the write clock CK1, the read video signal is compressed in the time direction by 475 times per horizontal scanning period. However, the aspect ratio of the cathode ray tube 7 is 5:3. On the other hand, the synchronization separation circuit 2 separates the horizontal and vertical synchronization signals HlV from the video signal 100 and outputs them to the video signal generation circuit 5, and also outputs the horizontal synchronization signal H to the PLL circuit 3. The PLL circuit 3 creates a clock CK from the input horizontal synchronization signal H and outputs it to the timing signal generation circuit 4. The timing signal generation circuit 4 generates a write clock CK1, a read clock OK2, a clock CK3, and a switching signal S for the switch circuit 6 from the clock CK, and sends the clocks CK1, CK2 and the switching signal S to the image compression circuit 1, the clock CK3, and the switching signal S. The inverted signal of the signal S is output to the video signal generation circuit 5, and the switching signal S is output to the switch circuit 6. The video signal generation circuit 5 generates additional information 20
0 is input, and this information is output to the terminal of the switch circuit 6 as a video signal that can be displayed on the cathode ray tube 7 based on the horizontal and vertical synchronizing signals H and V and the clock CK3.

FIG. 2 is a diagram showing an example of waveforms of the horizontal scanning timing of the cathode ray tube 7 of this example and a conventional cathode ray tube. Figure 2 (
A) corresponds to FIG. 4(A), and the actual screen scan width is narrower than the horizontal width of the cathode ray tube 7. Figure 2 (B
) corresponds to Figure 3 (A), and the horizontal scan width (excluding the scan width during the blanking period) is wider than that in Figure 2 (^), and there are As shown, an additional information period is provided. The additional information scan width corresponding to this additional information period corresponds to area A at the right end of the diagram shown in FIG. 3(A), and the actual screen scan width corresponds to the mouth. Therefore, the horizontal scanning signal 3H supplied to the cathode ray tube 7 is such that the horizontal scanning shown in FIG. 2(B) is performed, and the horizontal scanning amplitude is expanded to 574. It is a signal.

However, Sv in FIG. 1 indicates a vertical scanning signal. By the way, the switch circuit 6 is switched to the terminal H side by the switching signal S during the actual screen period of the cathode ray tube 7 shown in FIG. During the additional information period, it is switched to the terminal side and the video signal output from the video signal generation circuit 5 is output to the cathode ray tube 7. However, it is assumed that when the switch switching signal @S is at a high level, the switch circuit 6 is switched to the terminal H side, and when it is at a low level, it is switched to the terminal N side. Here, as mentioned above, the image time width of the video signal output from the image compression circuit 1 is compressed to 475 per horizontal scanning period, but the scanning amplitude of the horizontal width of the cathode ray tube 7 is 5.
74, the image displayed on the real screen display portion of the cathode ray tube 7 (the mouth portion in FIG. 3(A)) has the correct aspect ratio (4:3 aspect ratio). Furthermore, the cathode ray tube 7 has a long horizontal scan width, and displays the video signal of the additional information output from the video generation circuit 5 in the portion A of FIG. 3(A). The image compression circuit 1 reads the video signal from the line memory during the period when the input switching signal S is at high level, and the video signal generation circuit 5 reads the video signal from the line memory during the period when the input switching signal S is at high level. It is controlled to output a video signal corresponding to the additional information.

Therefore, on the tube surface of the cathode ray tube in this embodiment, the image shown in Fig. 3 (^)
As shown in Figure 2, it is possible to project the video signal 100 on the actual screen display section with an aspect ratio of 4:3, and display additional information 200 on the remaining additional information display section A, freeing up the screen surface of the wide aspect cathode ray tube. It can be used effectively without creating space, and since the additional information display section A that displays additional information is separated from the actual screen display section, additional information can be displayed without affecting the display on the actual screen. The screen can be displayed easily.

In the above embodiment, a case has been described in which a video signal with a standard aspect ratio is displayed on a cathode ray tube 7 having a wide aspect ratio, but in another embodiment, a video signal with a wide aspect ratio is displayed on a cathode ray tube with a standard aspect ratio. In this case, the cathode ray tube surface can be effectively utilized in the same manner as in the above embodiment. That is, the temporal direction of one vertical period of a wide aspect ratio video signal is compressed in the same manner as in the previous embodiment, horizontal scanning is also performed for the remaining period, and a video signal with additional information is formed in this period. If the information is fed into the cathode ray tube, an additional information display section A can be formed below the actual screen display section opening, as shown in FIG.

In the above embodiment, an example in which a cathode ray tube is used as the display section has been described, but a liquid crystal panel, a plasma display panel, etc. may also be used. Further, the cathode ray tube may be a dual beam cathode ray tube or the like that scans the actual screen display section and the additional information display section using different electron beams. Furthermore, the scanning of the cathode ray tube in the additional information display section may be a stroke scan that scans along the lines of characters, etc., and if the additional information has a memory function, it should be accessed only when rewriting the memory contents. Also good. Furthermore,
The wide aspect video signal may be a system compatible with the NTSC system, an HDTV signal, or the like. Further, the position of the additional information display section A is not limited to the example shown in Fig. 3, but may be set to the left side, to the upper side, to the left and right, or to the top and bottom, or to be set arbitrarily depending on the display content, etc. good. Furthermore, by switching the scanning frequency of the cathode ray tube, converting the number of scanning lines, or thinning out the signal, it is possible to combine it with an HDTV signal or the like.

[Effects of the Invention] As described above, according to the video signal display device of the present invention,
Even when the aspect ratios of the display section of the cathode ray tube and the video signal are different, there is an effect that the surface of the cathode ray tube can be used effectively without creating any empty space on the surface of the cathode ray tube.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the video signal display device of the present invention, FIG. 2 is a diagram showing an example of horizontal scanning timing waveforms between the cathode ray tube of this embodiment and a conventional cathode ray tube, and FIG.
The figure shows an example of the display on the cathode ray tube surface of this example, and FIG. 4 is a diagram showing an example of the display on the conventional cathode ray tube surface. 1... Image compression circuit 2... Synchronization separation circuit 3...
PLL circuit 4...timing signal generation circuit 5...
Video signal generation circuit 6... Switch circuit 7... CRT agent Patent attorney Noriyuki Ken Yudo Uji Hiroshi 1vA

Claims (1)

[Claims] In a video signal display device that displays the video signal on a display section having an aspect ratio different from that of the video signal, and also displays a separately input additional information signal,
a time axis compression means for compressing the time axis of the video signal at a predetermined compression ratio every predetermined period; Signal insertion means for inserting the signal of the additional information, and scanning in the horizontal direction of the screen of the video signal compressed by the time axis compression means, enlarged and scanned at an enlargement ratio that is the reciprocal of the compression ratio. 1. A video signal display device comprising: scanning means for expanding a time axis.