JPH0865583A - Display device - Google Patents

Abstract

PURPOSE: To display both a moving picture and a still picture to easily observe them by judging whether an input video signal is a moving picture signal or a still picture signal and selectively executing multi-gradation processing. CONSTITUTION: An R signal processing part 2 writes a digital signal covered from a primary color signal in a field memory 4 in each field, a field memory 5 delays the primary color signal by one field, a comparing part 6 mutually compares data read out from both the memories 4, 5 to discriminate whether an input video signal is a moving picture or a still picture. A G signal processing part 12 and a B signal processing part 22 are similarly constituted. A gate circuit 7 finds out AND for inputs from these processing parts 2, 12, 22 and outputs a detection signal and a control part 8 outputs a control signal corresponding to the detection signal. A selector 9 switches a primary color signal inputted to one terminal to two directions and outputted, one output from the selector 9 is outputted from an output terminal 27 and the other output is outputted front the terminal 27 through a multi-gradation processing part 10.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device capable of displaying a moving image from a television signal or the like and a still image from a personal computer or the like.

[0002]

2. Description of the Related Art Conventional display devices are generally used for displaying television signals and for displaying personal computer signals. Alternatively, a display device that can be used commonly for displaying a television signal and a personal computer signal has also been developed. Especially, in the case of using a plasma display panel, a moving image signal with many intermediate gradations from a television signal or the like. In order to display, the primary color signal converted into the digital signal is subjected to signal processing to increase the number of gradations in the multi-gradation processing section and displayed on the plasma display panel.

[0003]

However, there is a problem in that the contour of an image becomes unclear when signal processing for increasing the number of gradations is performed in the multi-gradation processing unit for a still image signal from a personal computer or the like. . The present invention discriminates whether a video signal input is a moving image signal or a still image signal, and selectively performs multi-gradation processing on the video signal input in accordance with the determination result, thereby producing a moving image such as a television signal. Another object of the present invention is to provide a display device capable of displaying still images from a personal computer or the like in an easy-to-see manner.

[0004]

A display device according to the first invention of the present application is provided in each input circuit of a primary color signal of a video signal, primary color signal determining means for determining whether a moving image or a still image, and these primary colors. A gate circuit for taking an AND output from the input from the signal discriminating means, a control section for outputting a control signal in response to the input from the gate circuit, and the primary color signals respectively inputted to one end, and the control section A selector for switching and outputting in two directions according to the control signal, and a circuit in which one of the outputs from the selector is connected to an output terminal and the other is connected to the output terminal via a multi-gradation processing section. Is characterized by. In the display device of the second invention of the present application, a first memory for writing the primary color signal input converted into a digital signal by the primary color signal determining means for each field, and a second memory for delaying the primary color signal input by one field. It is characterized by comprising a memory and a comparison unit for comparing the data read from the first memory with the data read from the second memory.

[0005]

According to the present invention, with the above-described configuration, the image data read from the first memory and the second memory of the primary color signal discrimination means are compared by the comparison section, and the data one field before the primary color signal input is compared with the current data. The comparison is made with the field data, and there is no difference in the case of a still image, but there is a difference in the comparison result in the case of a moving image, so the comparison of the primary color signal discrimination means provided for each primary color signal The gate circuit ANDs the result to determine whether it is a still image or a moving image, and inputs a detection signal to the control unit. The control unit switches the selector according to the detection signal and outputs it. In the case of, the primary color signal input to the selector is directly output to the output terminal, and in the case of a moving image, the primary color signal input to the selector is input to the multi-gradation processing unit. To increase the number of gradations And to output to the output terminal by performing signal processing. Therefore, the moving image signal from a television signal or the like is increased in the number of gradations by the multi-gradation processing unit so that an intermediate gradation can be displayed, and the still image signal from a personal computer or the like is not passed through the multi-gradation processing unit. Output to prevent the outline of the image from becoming unclear, and to automatically perform multi-gradation processing on the primary color signal input, so that moving images such as television signals and personal computers can be displayed. It is possible to display both still images from the etc. in an easy-to-see manner.

[0006]

1 is a block diagram showing an embodiment of a display device of the present invention. Primary color signals and RGB signals of a video signal from a television, a personal computer or the like are input to input terminals 1, 11 and 21, and an R signal input through the input terminal 1 is used as an R primary color signal discriminating means. The signal processing unit 2 determines whether it is a moving image or a still image, inputs a determination signal to the gate circuit 7, and the G signal of the primary color signals input via the input terminal 11 is used as primary color signal determination means. The G signal processing unit 12 discriminates whether the image is a moving image or a still image, inputs the discrimination signal to the gate circuit 7, and the B signal of the primary color signal inputted through the input terminal 21 is used as the primary color signal discrimination means. B signal processing unit 22
It discriminates whether it is a moving image or a still image, and inputs a discrimination signal to the gate circuit 7.

The R signal processing unit 2 converts the R signal input through the input terminal 1 into a digital signal by the A / D converter 3 and writes the current field data into the field memory 4 field by field. The data before the field is written in the field memory 5, and the data of the current field read from the field memory 4 and the data of the previous field read from the field memory 5 are compared by the comparison unit 6. The comparator 6 uses, for example, a comparator circuit, and when the video signal input is a still image, the data read from the field memory 4 and the data read from the field memory 5 are the same, but considering the influence of noise or the like. Then, a certain threshold value is provided for the comparison result to make a determination, "0" is output as a determination signal, and when the video signal input is a moving image, the data read from the field memory 4 and the data read from the field memory 5 are In contrast, a difference equal to or greater than a certain threshold is detected and "1" is output as a determination signal.

The G signal processing unit 12 and the B signal processing unit 22 are also configured in the same manner. When the video signal input is a still image, "0" is output as a discrimination signal, and when the video signal input is a moving image. Outputs "1" as a discrimination signal. An AND gate is used as the gate circuit 7, and an AND signal from each signal processing unit is taken to output a detection signal. When a signal “1” is input from each signal processing unit, Outputs "1", signal "0" otherwise.
Is output. The detection signal from the gate circuit 7 is input to the control unit 8, and in response to this input, the control unit 8 outputs a control signal and inputs it to the selector 9 to switch the selector 9.

On the input side of the selector 9, the R signal read from the field memory 4 of the R signal processing unit 2, the G signal read from the field memory 14 of the G signal processing unit 12, and the field memory of the B signal processing unit 22. When the B signal read from 24 is input and the signal “1” is input from the gate circuit 7, the control unit 8 switches the selector 9 so that the signal is input to the multi-gradation processing unit 10. When the signal “0” is input from the gate circuit 7, the control unit 8 switches the selector 9 so that the signal is output to the output terminal 27. The multi-gradation processing unit 10 uses a pseudo-halftone processing circuit (multi-gradation processing LSI) previously proposed by the present applicant, and is converted into digital signals by the A / D converters 3, 13 and 23. For the number of bits of the primary color signal or the number of bits reduced by the signal processing unit after that,
For example, a 5-bit signal is subjected to signal processing by increasing the number of gradations so as to become an 8-bit signal, and converted into a multi-gradation digital signal, and the signal is output to the output terminal 27.

Therefore, a still image signal from a personal computer or the like can be automatically output from the output terminal 27 without passing through the multi-gradation processing unit 10, and based on the output, it is displayed on the plasma display panel. If
The outline of the image can be displayed clearly. Also,
It is possible to automatically output a moving image signal from a television signal or the like from the output terminal 27 via the multi-gradation processing unit 10, and it is possible to increase the number of gradations. The gradation can be displayed, and the image can be displayed easily.

[0011]

As described above, according to the present invention,
Each primary color signal is discriminated as a moving image or a still image by the primary color signal discriminating means provided in the input circuit of each primary color signal, and the control unit automatically switches the selector based on the discrimination result. The still image signal is output without passing through the multi-gradation processing unit, and is displayed on the plasma display panel based on the output.
The outline of the image can be displayed clearly, and for a moving image signal such as a television signal, the number of gradations is increased and output via the multi-gradation processing unit. It is also possible to display halftones, and the image can be displayed in an easy-to-see manner.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of a display device of the present invention.

[Explanation of symbols]

 1 Input Terminal 2 R Signal Processing Section 3 A / D Converter 4 Field Memory 5 Field Memory 6 Comparison Section 7 Gate Circuit 8 Control Section 9 Selector 10 Multi-Gradation Processing Section 11 Input Terminal 12 G Signal Processing Section 13 A / D Conversion 14 field memory 15 field memory 16 comparing section 21 input terminal 22 B signal processing section 23 A / D converter 24 field memory 25 field memory 26 comparing section 27 output terminal

Claims (2)

[Claims] 1. A primary color signal discriminating means which is provided in each input circuit of a primary color signal of a video signal and discriminates whether it is a moving image or a still image, and outputs the AND from the inputs from these primary color signal discriminating means. A gate circuit, a control unit for outputting a control signal in response to an input from the gate circuit, and a selector for inputting the primary color signal at one end and switching the output in two directions according to the control signal from the control unit for output. And a circuit in which one of the outputs from the selector is connected to an output terminal and the other is connected to the output terminal via a multi-gradation processing section. 2. A first memory for writing the primary color signal input converted into a digital signal by the primary color signal determining means for each field, a second memory for delaying the primary color signal input by one field, and the second memory. The display device according to claim 1, further comprising a comparison unit that compares the data read from one memory with the data read from the second memory.