JP2003309784A - Video signal processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To insert a black line to a video signal without adding a means for holding the video signal. <P>SOLUTION: A video signal processor expands the number of vertical lines of an inputted video signal while performing vertical interpolation on the basis of a vertical interpolation coefficient. While expanding the number of lines after the expansion of the vertical lines so as to be a value including black lines, the processor counts the number of vertical lines, stops the cumulative addition of vertical interpolation coefficients for each fixed line to which the black line has to be inserted, and inserts a black signal to the line, thereby the black line is inserted without adding the means for holding the video signal. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal processing device for inserting a black line into a video signal input to a liquid crystal display device when a moving image performance is improved by performing black insertion driving.

[0002]

2. Description of the Related Art Recently, in a video display device using a liquid crystal, there has been a device for improving moving image performance by performing black insertion drive. The black insertion drive writes black in the video signal in view of the property that moving image characteristics are better to be displayed and disappear instantaneously (impulse display) than to be retained until the image information is rewritten in the next frame. By doing so, it is possible to bring it closer to the impulse display and improve the moving image performance.

Specifically, there are a method of repeating image writing and black writing on the entire screen, and a method of writing black on each screen portion (reference: Nikkei BP FLAT).
-PANEL DISPLAY-PANEL DISP
LAY 2002 p. 106 "Black insertion drive").

In the black insertion drive in which black writing is performed for each screen portion, it is necessary to insert a black line in the input image to the image display device. Usually, in order to insert a black line into an input video signal, a means for holding the input video signal is required.

[0005]

However, since a frame memory or a large number of line memories is required as a means for holding the input video signal, there is a problem that the circuit scale increases greatly.

In view of the above problems, the present invention uses a line number conversion device that is originally provided for displaying various video signals in a liquid crystal display device, and newly inserts a black line into an input video signal. The purpose is to reduce the increase in the circuit scale by performing the operation without adding the holding means.

[0007]

In order to solve the above problems, a video signal processing device of the present invention is a video signal processing device for expanding the number of vertical lines of an input video signal while performing vertical interpolation based on a vertical interpolation coefficient. That is, the number of vertical lines is counted while accumulating so that the number of lines after enlarging the vertical lines becomes a value including the black line, and the cumulative addition of the vertical interpolation coefficient is performed for each fixed line where the black line should be inserted. The feature is that the black line is inserted without adding a means for holding the video signal by stopping and inserting the black signal into the line.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is a video signal processing apparatus for expanding the number of vertical lines of an input video signal while performing vertical interpolation based on a vertical interpolation coefficient. While enlarging so that the number of lines after enlarging becomes a value that includes black lines, counting the number of vertical lines and stopping the cumulative addition of vertical interpolation coefficients for each fixed line where black lines should be inserted, and black lines are added to that line. By inserting the signal, the black line can be inserted without adding a means for holding the video signal.

According to a second aspect of the present invention, a vertical line for expanding the number of vertical lines of the input video signal while performing vertical interpolation based on the vertical addition coefficient cumulative addition value output from the vertical interpolation coefficient cumulative addition means described below. Number expansion means and a black line insertion signal generator for counting the number of vertical lines after expansion for each expanded video horizontal synchronization signal output from the vertical line number expansion means and outputting a black line insertion signal at each black line interval. Means, a vertical interpolation coefficient generating means for outputting a vertical interpolation coefficient based on an expansion rate of the video signal, and an output from the vertical interpolation coefficient generating means for each expanded video horizontal synchronizing signal output from the vertical line number expanding means. The vertical interpolation coefficients are cumulatively added, but when the black line insertion signal output from the black line insertion signal generating means is present, the cumulative addition of the vertical interpolation coefficients is stopped. A means for holding a video signal is added by including interpolation coefficient cumulative addition means and black line insertion means for outputting a black signal to an output video signal by the black line insertion signal output from the black line insertion signal generation means. This has the effect of inserting a black line without doing so.

According to a third aspect of the present invention, there is provided a video signal processing device for thinning a vertical line of an input video signal by controlling writing and reading of the video signal with respect to a means for holding a video signal for one line. A means for holding a video signal by inserting (n + 1) lines during writing n lines and setting one of the (n + 1) lines to a black line when a black line is inserted into the output video signal every n lines This has the effect of inserting a black line without adding.

According to a fourth aspect of the present invention, the vertical thinning means for thinning the vertical lines of the input video signal by controlling the writing and reading of the video signal with respect to the means for holding the video signal for one line, and the output video. When a black line is inserted into a signal every n lines, a read control unit for controlling the video signal read timing of the vertical thinning unit to read (n + 1) lines while writing n lines, and a vertical line number after thinning. Count, (n +
1) Black line insertion signal generation means for outputting a black line insertion signal for each line, and black line insertion means for outputting a black signal to an output video signal by the black line insertion signal output from the black line insertion signal generation means By having the above, there is an effect that a black line is inserted without adding a means for holding a video signal.

(First Embodiment) FIG. 1 is an example of a block diagram of a video signal processing apparatus of the present invention.

In FIG. 1, reference numeral 1 is a vertical line number expansion for expanding the vertical line number of an input video signal while performing vertical interpolation based on the vertical interpolation coefficient cumulative addition value output from the vertical interpolation coefficient cumulative addition means 4 described below. Reference numeral 2 denotes a black line insertion signal which counts the number of vertical lines after expansion for each expanded video horizontal synchronizing signal output from the vertical line number expansion means 1 and outputs a black line insertion signal at each black line interval. Reference numeral 3 denotes a generating means, and 3 denotes a vertical interpolation coefficient generating means for outputting a vertical interpolation coefficient based on an enlargement ratio of a video signal. Reference numeral 4 denotes the vertical interpolation for each expanded video horizontal synchronizing signal outputted from the vertical line number expanding means. The vertical interpolation coefficients output from the coefficient generating means are cumulatively added. When there is a black line insertion signal output from the black line insertion signal generating means, the vertical interpolation coefficients are cumulatively added. In the vertical interpolation coefficient accumulating means to stop, 5 is a black line insertion means for outputting a black signal in the output video signal with a black line insertion signal outputted from the black line insertion signal generating means 2.

FIG. 2 is a diagram showing how the number of vertical lines is expanded when the present invention is not used. FIG. 3 is a diagram showing how the number of vertical lines is enlarged when the present invention is used.

The specific operation will be described below. First, the input video signal is input to the vertical line number expansion means 1.

The black line insertion signal generation means 2 counts the number of vertical lines after expansion for each expanded video horizontal synchronizing signal output from the vertical line number expansion means 1 and outputs a black line insertion signal at every black line interval. To do.

The vertical interpolation coefficient generating means 3 outputs the vertical interpolation coefficient based on the enlargement ratio. Normally, the vertical interpolation coefficient cumulative addition means 4 cumulatively adds and outputs the vertical interpolation coefficients from the vertical interpolation coefficient generation means 3, but when the black line insertion signal output from the black line insertion signal generation means 2 is received, it is accumulated. The addition is stopped, and the vertical interpolation coefficient cumulative addition value that is the output holds the previous value.

The vertical line number expansion means 1 expands and interpolates the input video signal based on the vertical interpolation coefficient cumulative addition value from the vertical interpolation coefficient cumulative addition means 4.

When there is a black line insertion signal output from the black line insertion signal generation means 2, the black line insertion means 5 makes the video signal from the vertical line number expansion means 1 black,
Output.

An example of a normal vertical expansion operation by the vertical line number expansion means 1, the vertical interpolation coefficient generation means 3 and the vertical interpolation coefficient cumulative addition means 4 will be described with reference to FIG.

The vertical interpolation coefficient generating means 3 calculates the reciprocal of the enlargement ratio and outputs it as a vertical interpolation coefficient.

The vertical interpolation coefficient cumulative addition means 4 cumulatively adds the vertical interpolation coefficients. In the example of FIG. 2, since the input video signal of vertical 5 lines is expanded to the video signal of 8 lines, the expansion ratio is 8/5, and thus the reciprocal is 0.625.

The vertical line number expansion means 1 receives the vertical interpolation coefficient output from the vertical interpolation coefficient cumulative addition means 3,
Based on this and the input video signal data, the video signal after the expansion interpolation is calculated and output. Next, the operation when a black line is inserted using this vertical expansion will be described with reference to FIG. FIG. 3 shows an example in which one black line is inserted every four lines. Since it is desired to insert a black line at every black line interval, the number of vertical lines after enlargement is counted, and when the black line interval is counted, the cumulative addition of vertical interpolation coefficients is stopped.

This is because if the vertical interpolation coefficients are cumulatively added on the black line, the video signal that should be output is no longer output. Then, by outputting the black signal to the line where the cumulative addition of the interpolation coefficient is stopped, it is possible to insert the black line for every fixed line.

As described above, the black line can be inserted by stopping the cumulative addition of the vertical interpolation coefficients at the time of outputting a predetermined line and outputting the black signal. Therefore, since it is not necessary to add a means for holding the input signal with a simple circuit,
The advantageous effect that the increase in the circuit scale is small is obtained.

Although the line to be inserted is black, it goes without saying that another line or another video signal may be used.

In the above example, the case of expanding from 5 lines to 8 lines has been described, but it goes without saying that it is also possible to expand the number of other lines.

In the above example, black line 1 is set every 4 lines.
Although the line is inserted, it goes without saying that other lines may be inserted.

In the above example, black line 1 is set every 4 lines.
Although the line is inserted, it goes without saying that the number of black lines to be inserted may be another number.

In the above example, enlargement is performed, but it goes without saying that the number of lines of the finally displayed video may be the same size.

(Second Embodiment) In FIG. 4, 6 is a vertical thinning means, 7 is a read speed control means, 8 is a black line insertion signal generating means, and 9 is a black line insertion means. FIG. 5 is an operation explanatory diagram of vertical thinning in a case where the present invention is not used, and FIG.
FIG. 7 is an explanatory diagram of vertical thinning operation when black lines are inserted using the present invention.

Reference numeral 6 in FIG. 4 is a vertical thinning means for thinning the vertical lines of the input video signal by controlling the writing and reading of the video signal to the means for holding the video signal for one line, and 7 is the output video signal. When a black line is inserted every n lines, the video signal read timing of the vertical thinning means is set to (n +
1) Read control means for controlling to read the line,
Reference numeral 8 is a black line insertion signal generating means for counting the number of vertical lines after thinning and outputting a black line insertion signal for each (n + 1) line, and 9 is a black output from the black line insertion signal generating means. A black line inserting means for outputting a black signal to an output video signal by a line inserting signal.

The specific operation will be described below. First, the input video signal is input to the vertical thinning means 6. In the read speed control means 7, when a black line is inserted every n lines based on the write signal from the vertical thinning means 6 and the black line interval, the video signal read timing of the vertical thinning means 1 is set between n line writing. Control is performed so as to read (n + 1) lines.

The black line insertion signal generation means 8 counts the line read timing signal from the read speed control means 7 and outputs the black line insertion signal at every black line interval. When there is a black line insertion signal output from the black line insertion signal generation means 7, the black line insertion means 9 blackens the video signal from the vertical thinning means 6 and outputs it.

An example of a normal vertical thinning operation by the vertical thinning means 6 will be described with reference to FIG. FIG. 5 shows an example of thinning from 8 input lines to 4 output lines using a FIFO. FIFO # WE in FIG. 5 is a write enable signal to the FIFO and has a positive polarity. As shown in FIG. 5, the input video is written into the FIFO at a timing of one line out of two lines, and the FIFO is read at a cycle of two input lines on the read side.
By reading the video signal from, the number of lines is thinned from 8 lines to 4 lines.

Next, the operation for inserting a black line by using the vertical thinning will be described with reference to FIG. In the example of FIG. 6, since black lines are inserted every 4 lines, 5 lines are read while writing 4 lines. Then, black insertion is performed by setting one of the read five lines as a black line.

As described above, black lines can be inserted by reading (n + 1) lines while writing n lines in the image holding means for one line and setting one of the lines as a black line. Therefore, since it is a simple circuit and it is not necessary to add means for holding the input signal, the advantageous effect that the increase in the circuit scale is small can be obtained.

Although the line to be inserted is black, it goes without saying that another line or another video signal may be used.

In the above example, the thinning-out from 8 lines to 4 lines is performed, but it goes without saying that the thinning-out of other lines may be performed.

[0040]

As described above, according to the present invention, when a black line is inserted in a video signal, the vertical interpolation enlarging means and the vertical interpolation means are diverted, so that it is not necessary to add means for holding the input signal. Therefore, the increase in the circuit scale can be suppressed.

[Brief description of drawings]

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

FIG. 2 is a diagram showing an example of vertical line expansion interpolation in a conventional part of the apparatus.

FIG. 3 is a diagram showing an example of black line insertion in the same apparatus.

FIG. 4 is a diagram showing a block diagram of a video signal processing device according to a second embodiment of the present invention.

FIG. 5 is a diagram showing an example of vertical thinning-out in the conventional portion of the device.

FIG. 6 is a diagram showing an example of black line insertion in the apparatus.

[Explanation of symbols]

1 Vertical line number expansion means 2 Black line insertion signal generation means 3 Vertical interpolation coefficient generating means 4 Vertical interpolation coefficient cumulative addition means 5 Black line insertion means 6 Vertical thinning means 7 Read speed control means 8 Black line insertion signal generation means 9 Black line insertion means

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Claims (4)

[Claims] 1. A video signal processing device for expanding the number of vertical lines of an input video signal while performing vertical interpolation based on a vertical interpolation coefficient, wherein the number of lines after expansion of the number of vertical lines is a value including a black line. Video signal processing characterized by counting the number of vertical lines and stopping the cumulative addition of vertical interpolation coefficients for each fixed line at which black lines should be inserted, and inserting black signals into the lines while enlarging so that apparatus. 2. A vertical line number expansion means for expanding the vertical line number of an input video signal while performing vertical interpolation based on the vertical interpolation coefficient cumulative addition value output from the vertical interpolation coefficient cumulative addition means, and the vertical line. A black line insertion signal generating means for counting the number of vertical lines after expansion for each expanded video horizontal synchronizing signal output from the number expansion means, and outputting a black line insertion signal at each black line interval, and an expansion rate of the video signal. Vertical interpolation coefficient generating means for outputting a vertical interpolation coefficient based on the above, and vertical addition coefficient output from the vertical interpolation coefficient generating means for each expanded horizontal image horizontal synchronizing signal output from the vertical line number expanding means. If there is a black line insertion signal output from the black line insertion signal generation means, vertical interpolation coefficient cumulative addition means for stopping the cumulative addition of vertical interpolation coefficients, and the black A video signal processing device, comprising: a black line inserting means for outputting a black signal to an output video signal by the black line inserting signal output from the line inserting signal generating means. 3. A video signal processing device for thinning out vertical lines of an input video signal by controlling writing and reading of the video signal with respect to a means for holding a video signal for one line, wherein n lines are output to the output video signal. When a black line is inserted every time, (n + 1) lines are read out while n lines are being written, and one of the (n + 1) lines is made a black line to drive the black insertion without adding a means for holding a video signal. A video signal processing device, characterized in that 4. A vertical thinning means for thinning out vertical lines of an input video signal by controlling writing and reading of a video signal with respect to a means for holding a video signal for one line, and black for every n lines to an output video signal. When inserting a line, read control means for controlling the video signal read timing of the vertical thinning means to read (n + 1) lines while writing n lines, and the number of vertical lines after thinning is counted to obtain (n + 1) lines. A black line insertion signal generating means for outputting a black line insertion signal for each time; and a black line insertion means for outputting a black signal to an output video signal by the black line insertion signal output from the black line insertion signal generating means. A video signal processing device characterized by the above.