JPH0810914B2 - Video signal processing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a video projection system (hereinafter abbreviated as VPS) to magnify and project a video, in which the position of a subtitle such as a movie can be changed. Regarding display device.

2. Description of the Related Art In recent years, video software, especially movie software, has been enriched, and TVs have become larger in screen size. In the future, it is considered that VPS will be used for larger screens.

FIG. 3 is a schematic block diagram of VPS. 1 in the figure is a Y / C that separates the video signal into a luminance signal and a chrominance signal.
Separation circuit, 2 is an image amplification circuit for amplifying the luminance signal Y, 3
Is a color signal demodulation circuit for returning a color signal to an I / Q or color difference signal, 4 is a matrix circuit for obtaining an RGB signal, 5 to 7
Is a cathode ray tube of RGB (hereinafter abbreviated as CRT), 8-10 is CRT 5-7
, A lens for converging the light of 11, a sync separation circuit for obtaining a sync signal from a video signal, a vertical deflection circuit, a horizontal deflection circuit for generating a horizontal deflection and a high voltage, and a screen for projecting a projected image. .

The operation of the VPS configured as described above will be briefly described below.

The input video signal is separated into a Y signal which represents a luminance signal component and a C signal which represents a chrominance signal component in the video signal which is input to the Y / C separation circuit 1, and the Y signal is the video amplification circuit 2.
The C signal is input to the matrix circuit 4 via the color signal demodulation circuit 3 for demodulation, is converted into RGB primary color signals, and drives the CRTs 5 to 7.

On the other hand, the synchronization relationship is separated from the video signal by the sync separation circuit 11, one of which enters the vertical deflection circuit 12 in the vertical direction and the other of which outputs a signal for performing horizontal scanning in the horizontal deflection circuit 13. To do. The horizontal deflection circuit 13 also includes a high voltage generation circuit.

The images projected on the CRTs 5 to 7 are projected on the screen 14 by the lenses 8 to 10 to reproduce a large image.

The VPS as described above can have the following functions.

As shown in Fig. 4, it is usually 4: 3 for NTSC video signals.
Although it has the aspect ratio of, the video source has images such as cinema size with the top and bottom missing like a movie. In such a case, as shown in FIG. 5, for example, it is possible to change the horizontal screen size while keeping the vertical direction constant, and to extend the vertically missing image vertically into a single image and horizontally extend it at the same ratio. A function is being considered that allows you to enjoy powerful images that are complete.

This expansion can be achieved by changing the horizontal / vertical deflection current (changing the amplitude).

Depending on the type of the video source lacking in the upper and lower parts, the subtitle super is placed outside the video portion, and in this case, the subtitle super becomes invisible when it is enlarged to one screen.

Therefore, using a field memory, a function of storing only the subtitle superimposition, delaying it, and synthesizing it with the video of the next field so that only the subtitle superposition can be moved and viewed can be considered.

Problems to be Solved by the Invention As a means for moving and synthesizing a subtitle super, there is a method of taking a simple OR, but it may be pure white depending on the video state of the position to be synthesized, and the characters of the moved subtitle super There is a problem that you can not see.

In view of the above problems, the present invention is to provide a video signal processing device in which a subtitle supermarket can be easily viewed even when a video is displayed on one screen.

Means for Solving the Problems In order to solve the above problems, the video signal processing device of the present invention compares the data delayed by the field memory with a predetermined value, and outputs the original video by the comparison signal output. By switching the signal and the subtitle part of the delayed video signal, that is, if the value to be compared is placed as close to the black level as possible, the width of the comparison signal becomes wider and the part from which the original video signal is extracted becomes wider. The rising and falling edges of the characters in the subtitles are slowed down due to band limitation, and as a result, the combined characters have a bordered shape and are easy to see.

Effect The present invention has the above-described configuration, and when the above-mentioned missing image is enlarged and projected onto one screen, the subtitles are outside the effective video signal (above and below the missing part), When this is moved and combined, it is less affected by the original video signal and can be easily viewed.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a video signal processing device according to an embodiment of the present invention.

15 is an A / D converter for analog-to-digital conversion of the Y signal separated by the Y / C separation circuit, 16 is an AND gate for extracting only the caption portion of the video signal, 17 is a field memory for delaying the Y signal Reference numeral 18 denotes a comparator that compares predetermined comparison data with the output data of the field memory 17, and 19 denotes a selector that switches the Y signal A / D by the output of the comparator 18 and the output of the field memory 17.

Regarding the video signal processing device configured as described above,
The operation will be designed below.

The Y / C separated Y signal is converted into a digital signal by the A / D converter 15. Here, the sampling frequency is 4Fsc (Fsc
= 3.579545MHz), 8-bit, 256 gradations are selected. Memory 17 is FiFo (first in first out)
A type of field memory is used. This memory 17
Is written in synchronization with the basic vertical sync signal, and the reading is performed in consideration of the delay time so that the subtitles come to the desired position of the video data.

Since the comparator 18 creates a switching signal from the output of the field memory 17, the subtitle has a lot of white characters, so the comparison is made with a certain value, and if it is large, the signal is "H", and if it is small, the signal is "L". Is output.

The selector 19 switches the output of the A / D converter 15 when it is small, and the delay output of the field memory 17 when it is large, by the comparison output of the comparator 18, from the original subtitle position to the desired position, It is moved and output as a composite form.

In this switching, as shown in FIG. 2, the values to be compared are set at positions as close to black as possible so that the A / D converter 1
The output of 5 is sampled widely, and the output of the field memory 16 is band-limited, so that it is blunt and is combined, so that it becomes apparent with a bordered character and is easy to see.

With the above configuration, even when subtitles outside the video are rearranged inside the video, the subtitles are not affected by the original video and can be easily viewed.

Although the color signal is not described in this embodiment, it goes without saying that it can be suppressed by the output of the comparator 17 like the selector 18.

In the above embodiment, the input of the selector 19 is the original Y signal and the output signal of the field memory 17, but instead of the output signal of the field memory 17, a fixed value is input and The subtitle super may be always displayed as a bright screen regardless of the amplitude of the output signal of the memory 17. Images with good contrast can be obtained.

EFFECTS OF THE INVENTION As described above, according to the present invention, even when a subtitle outside a video is rearranged in a video, it is possible to make it easier to see without being affected by the original video.

[Brief description of drawings]

FIG. 1 is a schematic block diagram of a video signal processing device according to an embodiment of the present invention, FIG. 2 is a conceptual diagram thereof, FIG. 3 is a block diagram of a conventional video display device, and FIG. FIG. 5 is a diagram showing an image, and FIG. 5 is a diagram showing an enlarged display example of FIG. 15 ... A / D converter, 16 ... memory, 17 ... comparator, 18 ...
…selector.

Claims (2)

[Claims] 1. When synthesizing an analog-digital converted first television signal and a second television signal which is stored and delayed and read out, the second television signal is predetermined. A video signal processing device, characterized in that the first television signal and the second television signal are switched by means for comparing the obtained value and the comparison signal output. 2. A means for comparing a second television signal with a predetermined value, and by the comparison signal output,
The video signal processing device according to claim 1, wherein the first television signal and a predetermined value are switched.