JPS61214873A - Color television receiver - Google Patents

Abstract

PURPOSE:To display compound information by time-compressing a video signal, reading the same signal twice, displaying a two-times concentration and inserting an on-screen signal into an empty part by the time compression so that the usual TV picture can be received by a high definition TV. CONSTITUTION:When switches S1 and S2 fall to an (a) side, the high definition picture can be received and when they fall to a (b) side, an NTSC signal can be received. R, G and B signals of an NTSC of the main signal are time- compressed by a time compressing double scanning circuit 2, further, the number of the scanning line is doubled by a double scanning, the signals are drawn close to the left edge on a screen 1, formed so that 4:3 can be obtained on the displaying element, and inputted to an adder synthetic circuit 3. At such a time, the R, G and B signals are time-compressed by 4/5 only. A and B (shown in the figure) are input/output waveforms in the double scanning circuit 2, A is an original waveform, and B is a read signal waveform. The time T in the same figure is a time blank part when the time is compressed so as to match with the ratio of the above-mentioned horizontal and longitudinal ratio 4:3, and here, the information of an on-screen signal, etc., is inserted.

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention relates to a color television receiver (hereinafter referred to as a television), particularly a multi-system color television receiver that can switch between high-definition television, which will become popular in the future, and current standard television. This invention relates to television receivers.

BACKGROUND OF THE INVENTION High definition televisions have an aspect ratio of 5:3 and regular televisions have an aspect ratio of 4:3. If you switch between the two, a blank area will appear on the display element, and the horizontal frequency will change between approximately 31K)lz and approximately 15K).
I had to switch to KHz and two.

Problems to be Solved by the Invention As described above, in the past, blank areas occur, but these blank areas are very unsightly and do not allow effective use of display elements. Additionally, there was a problem in that the deflection circuit became complicated.

Means for Solving the Problems The present invention compresses the time of a video signal so that a high-definition television receiver can receive a normal television image, and also reads out the same signal twice to display double density. The system is configured to insert on-screen signals and the like into the spaces left open by time compression, and display composite information.

Effect of the Invention With the above-described configuration, the present invention scans the entire screen in order to make effective use of blank areas.

Then, since an image with an aspect ratio of 4:3 is displayed on a screen with an aspect ratio of 5:3, the horizontal area is expanded, and the video signal is time-compressed in the horizontal direction, and the same signal is read out twice with further synchronization, resulting in double scanning. Then, on-screen or picture-in-picture signals are inserted into the remaining time to make effective use of the screen.

Example FIG. 1 shows an embodiment of the present invention.

In FIG. 1, 1 is a CRT screen, and the display elements on the screen 1 have an aspect ratio of 5:3. Sl and S2 are switches, and the switch 81. When you flip it to the S2'ilL side, you can see a high-definition image and switch 81. If you turn it to the S2'ib side, you can receive NTSC signals. Figure 2 shows the situation. Figure 2 (&) is a front view of the screen in high-definition display, Figure 2 (b) is a front view of the screen in normal mode, and B, C , D, etc. are on-screen or picture-in-picture parts, which will be described later. The master's NTSC R-G-B signal is time-compressed by the time-compression double scan circuit 2, and the number of scanning lines is doubled by double scan, moved to the left edge of the screen 1, and displayed on the display element 4: 3 and is input to the addition/synthesizing circuit 3. At this time, the R-G-B signal is time-compressed by +. This may be done by using a cane or by converting it into a digital signal and using a memory. Since the method is already well known, it will be omitted.

Next, the character generator for on-screen and the memory for character multiplexing are designed to read out the clock timing so that the on-screen screen 61 as shown in Figure 2.
You can display the full literary long screen γ.

The sub-signal enters the NTSC picture-in-picture circuit 6,
After all, if the read timing is adjusted, the picture-in-picture screen 9 as shown in FIG. 2 can be easily displayed. This is also well known in terms of circuits, so it will be omitted. The deflection output circuit 1o performs horizontal scanning as a king.
31 Set to KH2.

Since 1126 lines are proposed for high definition, the output operation for horizontal scanning corresponding to this is performed.

In the case of NTSG, it can be changed to 625 lines by connecting switch s2 to the b side, but with double scan it is 1050 lines.
Make it into a book. This is also a well-known circuit.

Figure 3 shows the circuit for double scan.
The RGB signals of TSC are converted to mu/D converters 11R, 11G, 1
2H memo 1J12R converted to digital by 1B and configured with RAM.

After storing it in 12G and 12B and matching the tie bangs,
Read twice at about twice the speed, D/MU converter 13R,
13G and 13B restore the original analog signal. FIG. 4 shows the input/output waveforms in FIG. 3, where FIG. 4(A) is the original waveform and FIG. 4(B) is the signal waveform read out by double scan.

T is a time gap when compressed to match the above-mentioned aspect ratio of 4:3. You will enter other information here.

Effects of the Invention As described above, according to the present invention, a high-definition television screen and a normal television screen can be viewed on one television, and other information such as picture-in-picture and on-screen can be viewed simultaneously.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a color television receiver according to an embodiment of the present invention, Fig. 2 (A) is a front view of a CRT screen when displaying the same high-definition screen, and Fig. 2 (B) is a block diagram of a color television receiver according to an embodiment of the present invention. A front view of the (jRT screen) when displaying the same NTSC signal received image, Figure 3 is a block diagram showing the circuit for the same double scan, and Figures 4 (A) and (B) show the operation of each part of the same. It is an input/output waveform diagram. 1... Screen, 2... Time compression/double scan circuit, 3... Addition/synthesizing circuit, 4...
...Kirakuta Generator for on-screen, 5.
・Video memory for multiplexing characters, 8...NTS
C picture-in-picture circuit, 1o...Deflection output circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 ＾ Loco? Large ζ − Ichijo

Claims (1)

[Claims] The video signal is time-compressed so that a high-definition television receiver with a 5:3 aspect ratio can receive a regular television image with an aspect ratio of 4:3, and the same signal is read out twice for double-density display. A color television receiver configured to display composite information by inserting on-screen signals, character multiplex signals, and picture-in-picture signals into the areas left vacant by time compression.