JPH0368291A - Picture display system - Google Patents

Abstract

PURPOSE:To display a picture with high accuracy on a current television receiver with a simple means by outputting a scanning line of an extracted pattern as a scanning line of a current television signal. CONSTITUTION:When a full pattern display mode is selected by a display setting section 10, a MUSE signal inputted to a vertical extraction section 4 is subject to 3/1 line conversion and 344 effective scanning lines are generated and written in a buffer memory 5 via a changeover circuit. A signal read from the buffer memory 5 is converted into a signal synchronously with a horizontal synchronizing signal and a vertical synchronizing signal with an NTSC formatter 6, converted into an analog signal by a D/A converter 7 and outputted to an NTSC receiver.

Description

[Detailed Description of the Invention] [Industrial Field of Application]
Regarding the image display method that converts and displays video signals according to the current television system, in particular, extracts a part of the high-definition television system screen and displays it on the current television screen without reducing the number of blank lines. It is intended to do so.

[Tracking technology]

As a new television system to replace the current television system, high-definition television not only improves picture and sound quality, but also provides advanced visual psychological effects such as a sense of presence and impact that far exceeds that of the current television system. For example, a high-definition system has been proposed, and MtJSE is a transmission system for this high-definition system.
A method has been proposed.

Since the MUSE system is significantly different from current television systems, such as the NTSC system, in screen format, scanning system, audio system, etc., the MUSE signal cannot be reproduced as is using an NTSC system receiver. Therefore, the number of scan lines between both methods.

ML by absorbing differences in aspect ratio, line frequency, etc.
M for converting JSE signals to NTSC signals and displaying them
A USE/NTSC converter (down converter) has been proposed.

FIG. 4 is a diagram showing an example of displaying the output of the down converter on an NTSC screen, in which the effective scanning line 1032 of the MUSE signal
This is a mode in which the number of lines is reduced to 1/3 to 344 and allocated to 480 effective scanning lines of the NTSC system, and an NTSC output is obtained without changing the MtJSE system's 7 aspect ratio of 16:9. According to this mode, since the aspect ratio of the NTSC system is 4:3 (16:12), a blank area of about 30% of the number of effective scanning lines appears at the top and bottom of the screen, but the horizontal direction matches the MUSE screen. do.

[Problem to be solved by the invention]

By the way, in the conventional example mentioned above, the number of scanning lines of the high-definition television signal is reduced and displayed by allocating it to the scanning lines of the current television signal, making it impossible to display a high-quality image. It's inconvenient.

An object of the present invention is to provide an image display method that can display a high-definition image when converting a high-definition television signal into a current television signal and displaying the converted image.

[Means to solve the problem]

The present invention extracts a part of the screen according to the high-definition television system in an image display system that converts a video signal according to the high-definition television system into a video signal according to the current television system and displays the image. The video signal forming the screen is converted into a video signal according to the current television system and displayed.

[For production]

In this configuration, in order to select a part of the screen according to the high-definition television system and display it on the screen according to the current television system, the scanning lines forming the selected screen are extracted from the high-definition television signal, Further, from the extracted scanning line, a signal whose number of samples matches the current television signal is extracted in the horizontal direction. In this way, high-quality images based on the high-definition television system can be displayed on a receiver using the current television system.

(Embodiment) FIG. 1 is a block diagram showing an embodiment of an image display method according to the present invention, and shows an example in which a MUSE signal, which is one of the high-definition signals, is converted into an NTSC signal and displayed.

In FIG. 1, an MtJSE baseband signal received by a BS antenna and obtained through a BS tuner passes through a low-pass filter 1 with a cut-off frequency of 8.15 MHz, and then is converted into a digital signal by an AD converter 2. A
The sampling frequency in the D converter 2 is the resampling frequency of MUSE 16.2M1 (z).

The MUSE signal converted into a digital signal by the AD converter 2 is de-emphasized by a de-emphasis circuit 3 and then manually inputted to a vertical extraction section 4.

The vertical extraction unit 4 performs scanning line reduction processing to generate l-line signals from 3 lines of the MUSE signal and reduce the 1032 effective scanning lines of the MU'SE signal to 1/3, 344 lines, or the effective scanning of the MUSE signal. 48 consecutive lines from 1032 lines
Performs scanning line extraction processing to arbitrarily extract 0 scanning lines (the number of effective scanning lines of NTSC), and supplies the generated or extracted luminance signal Y9 color color difference R-Y and B-Y of each line to the buffer memory 5. do. Scanning line reduction processing is performed when the full screen display mode that displays the entire MUSE screen on an NTSC screen is selected, and scanning line extraction processing extracts and displays a part of the MUSE screen on an NTSC screen. This is done when the extraction screen display mode is selected.

The buffer memory 5 is a memory that sequentially stores one field's worth of luminance signals and color difference signals.Since signal writing and successive output timings differ between the MUSE signal and the NTSC signal, the buffer memory 5 is a memory that is necessary to absorb the time difference. has a capacity,
An input signal is written to a storage location designated by a write address signal WA, and a signal is read from that storage location by a subsequent address signal RA. The signal read from the buffer memory 5 is synchronized with the horizontal synchronizing signal HD and the vertical synchronizing signal VD by the NTSC formatter 6 to become an NTSC video signal, which is converted into a DΔ conversion analog signal and then output.

The MUSE signal converted into a digital signal by the 8-digit converter 2 is supplied to the MtJSE timing unit 8. MUSE
The timing unit 8 detects a horizontal synchronization signal and a vertical synchronization signal (frame pulse) from the input MtJS signal, generates various timing signals, and outputs various timing signals to the AD converter 2. Vertical extractor 4. ('') is supplied to the buffer memory 5 and the NTSC timing unit 9, which will be described later.

Horizontal open (The υ1 signal is inverted from the 1st sample point to the 11th sample point on each line of the MUSE transmission signal, and this horizontal open) I signal to 1
6.2 Regenerate the resampling signal SPt of Mllz. In addition, the frame pulse is inserted into each frame of the MtJSE transmission signal using two lines, and the waveforms of these two lines have opposite polarities, so they can be easily distinguished from the video signal. , This allows frame pulses (vertical synchronization signals) to be detected accurately.

The NTSC timing unit 9 generates various timing signals based on the synchronization signal detected by the MIJSE timing unit 8 and the generated timing signal, and sends the address signals RA to the buffer memory 5 and the N'FSC formatter 6. Horizontal and vertical synchronization signals HD and VD, DA
A sampling signal SP2 is supplied to the converter 7.

The display setting unit 10 selects either the full screen display mode or the extraction screen display mode described above, and sends a signal representing the selected mode and a signal indicating the extraction position of the screen when in the extraction screen display mode. M, US 25447
9 section 8 and NTSC timing section 9. Both timing sections 8 and 9 control the vertical extraction section 4 and the buffer memory 5 based on these signals, and when in the full screen display mode, the vertical extraction section 4 performs the scanning line reduction process described above, and changes the extraction screen display mode. When , scanning line extraction processing is performed.

FIG. 2 is a block diagram showing the main parts of the vertical extraction section 4, and typically shows a processing circuit for a luminance (Y) signal. This circuit consists of first and second IH memories 4 that sequentially delay the luminance (Y) signal of the MUSE signal by one line (H).
0 and 41, input signal and IH memory 40 and 41
Take the weighted average of three consecutive lines with the output signal of l
A weighted average circuit 42 that generates a line signal. Either the output of the 111 memory 41 or the output of the weighted average circuit 42.
It is composed of a switching circuit 43 for selecting the one.

In such a configuration, when the full screen display mode is first selected in the display setting unit 10, the MUSE signal input to the vertical extraction unit 4 is converted into 3 lines/1 line by the IH memory 40° 41 and the weighted average circuit 42. converted, 103
344 effective scan lines are generated from the two effective scan lines. This generated scanning line is written into the buffer memory 5 via the switching circuit 43. In the buffer memory 5, the written MtJSE signal is divided into three samples in the water f direction.
74 is read as an NTSC signal.

Furthermore, when the extraction screen display mode is selected in the display setting section IO, the manually inputted M LJ S E signal is transmitted to the vertical extraction section 4.
is delayed by the IH memories 40 and 41 of the switching circuit 4.
3 and then written to the buffer memory 5. The IH memories 40 and 41 extract and output 480 consecutive scanning lines forming the screen designated by the display setting section 10. In the Huffer memory 5', 132 samples out of 374 horizontal samples of the MUSE signal are written.

The signals read from the buffer memory 5 are horizontal and vertical synchronization signals HD and VD in NTSC Formantalo.
The signal is synchronized with , is converted into an analog signal by the DA converter N7, and is output to an NTSC receiver (not shown).

Therefore, according to this embodiment, by first selecting the full screen display mode to display the entire screen of MUSE on the NTSC screen, and then selecting any part of the screen from the NTSC screen and switching to the extraction screen display mode. As shown in FIG. 3, the selected part of the screen is displayed on the NTSC receiver as a high-definition image similar to the MUSE image.

In the above-mentioned embodiment, switching between the full screen display mode and the extracted screen display mode was described, but the present invention is of course not limited to this and can be applied to switching between other display modes. be.

Further, the configuration of the vertical extraction section is not limited to the 3-tap configuration using two IH memories, but it goes without saying that it may also be a 5-tap configuration, a 7-tap configuration, or the like.

(Effects of the Invention) According to the present invention, a screen having a size corresponding to the current television system screen is extracted from a high-definition television system screen, and the scanning lines of this extracted screen are converted into the current television system screen. Since the images are output as scanning lines, it is possible to display high-definition images on current television receivers using simple means.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the image display method according to the present invention, Fig. 2 is a block diagram showing the main parts of the vertical extraction section in Fig. 1, and Fig. 3 is the screen configuration of the extraction screen display mode. Figure 4 shows the output screen of the down converter. 4... Vertical extraction section, 5... Buffer memory, 6...
・NTSC formatter, 8...MUSE timing section, 9...NTSC timing section, 0...Display setting section.

Claims (2)

[Claims] (1) In an image display method that converts a video signal based on a high-definition television system into a video signal according to the current television system and displays the image, a part of the screen according to the above-mentioned high-definition television system is extracted; An image display system characterized in that a video signal forming a screen is converted into a video signal according to the current television system and displayed. (2) In an image display method that converts a high-definition television video signal into a current television video signal and displays it, the number of scanning lines of the high-definition television video signal is reduced. A first display method that displays the entire screen of the high-definition television system on the screen of the current television system; and a first display system that extracts a part of the screen of the high-definition television system to reduce the number of scanning lines. and a second display method for displaying on a screen according to the current television method, and the image display method is characterized in that the image is displayed by selectively switching between the first and second display methods.