JP4004624B2 - How to adjust the monitor - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
INDUSTRIAL APPLICABILITY The present invention is suitable for application to a monitor adjustment method, particularly color adjustment of a color monitor used in the multimedia field such as the Internet, plate making, printing, DTP (Desktop Publishing) field, and other fields handling colors on a monitor. The present invention relates to a monitor adjustment method.
[0002]
[Prior art]
The color reproduction of a color monitor is determined by the luminance of the primary colors of R (red), G (green), and B (blue) of the monitor main body, but the balance of the luminance differs depending on the function of the monitor main body and individual differences. Even if the input signals to the monitors have the same magnitude, it is necessary to adjust the brightness for each monitor in order to adjust the color tone between the monitors. Usually, this brightness is evaluated by a white color called white balance.
[0003]
As a conventional method for adjusting the white balance of a color monitor, (1) a method of actually measuring and adjusting color patches such as R, G, B, white and gray (R + G + B) with a measuring device, and (2) R , G, B, white and gray (R + G + B) color patches and natural images to display and adjust subjectively, (3) separately printed color patches and natural images as a reference The same image can be displayed on a monitor and compared, and subjective adjustment can be made so that both match.
[0004]
[Problems to be solved by the invention]
However, the conventional method (1) can be adjusted accurately, but requires an expensive measuring device and specialized knowledge, and the burden on the cost and workload is too large for a general user to perform. There is.
[0005]
Further, the methods (2) and (3) can be performed relatively easily, but depend on the subjectivity, so that there is a large variation among individuals and there is a problem that quantitative adjustment is difficult.
[0006]
The present invention has been made to solve the above-mentioned conventional problems, and does not require an expensive measuring device or specialized knowledge, and further provides a monitor adjustment method capable of easily and accurately performing objective color adjustment. The issue is to provide.
[0007]
[Means for Solving the Problems]
In the present invention, when the primary colors of R, G, and B are displayed adjacent to black on a monitor with adjusted white balance, the maximum pixel value for which the boundary line with black cannot be determined for each primary color is determined for each primary color. The maximum brightness level that is determined in advance as a reference balance value and is displayed on the same monitor, with the primary colors set as the reference balance value adjacent to black, and the boundary line with black cannot be distinguished for each primary color. Further, the problem is solved by adjusting the brightness of each primary color of the monitor.
[0008]
Here, the basic principle of the monitor adjustment method of the present invention will be described. For the sake of convenience, adjustment of R is taken as an example. As shown in FIGS. 1 and 2, the x-axis is the R input signal and the y-axis is the luminance, and the relationship between the two is shown without changing the 0 (origin) point. When the R luminance is lowered so that the maximum luminance value L becomes L ′, the slope of the graph changes from FIG. 1 to FIG. As a result, since the input signal value is low, it cannot be distinguished from the black background, that is, the point a in FIG. 1 at which the R color cannot be seen changes to the point b in FIG.
[0009]
The present invention utilizes this phenomenon, and if FIG. 1 represents a normal state, a point a where R cannot be distinguished from black is set as a reference point (reference balance value), and this point is maintained. By doing so, the luminance of R is adjusted. G and B are similarly adjusted.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0011]
FIG. 3 is a flowchart showing an outline of an operation procedure of the monitor adjustment method of the first embodiment according to the present invention, and FIG. 4 is a description conceptually showing an adjustment color chart applied to this embodiment. FIG.
[0012]
In this embodiment, the white balance of the monitor to be used is adjusted, an adjustment chart created by making each of the primary colors of R, G, and B adjacent to black is displayed on the monitor, and each primary color is displayed in black as a unit. The maximum pixel values for which the boundary line cannot be determined are determined in advance as reference balance values R0, G0, and B0.
[0013]
The white balance of the monitor can be adjusted, for example, by actually measuring the color chart displayed on the monitor using a measuring device. When adjusting this monitor, or when determining the reference balance value and adjusting the monitor, which will be described later, the appearance of the color (color chart) differs depending on the ambient brightness, etc. (Use a dark room or wear a monitor hood).
[0014]
An example of a specific process for determining the reference balance value will be described below.
[0015]
For example, when the reference monitor to be used is adjusted to the color temperature D65, Bk (black: R = G = B = 0) and R, G, and B are displayed on the monitor as shown in FIG. Displays a color chart with the primary colors adjacent. At this time, it is assumed that each of the R, G, and B gradation values is represented by 8 bits of 0 to 255 in a range of R luminance: G luminance: B luminance = 0: 0: 0 to 1: 1: 1 (relative value). The reference balance value is set as a gradation value (pixel value). At the time of setting, by using application software or a specific program, the luminance value of each primary color is continuously increased or decreased, and the point where the boundary line between Bk and R, G, and B primary colors cannot be determined is determined for each color. The reference point (reference balance value) is determined.
[0016]
Here, the predetermined reference balance values R0, G0, B0 are represented by (R, G, B) pixel values, and R0 = (20, 0, 0), G0 = (0, 16, 0), Let B0 = (0, 0, 32).
[0017]
Next, when the color of the monitor is readjusted after adjusting the white balance for the monitor, each reference balance of R, G, and B determined in advance as described above in this embodiment is used. Since there is only one type of value, an adjustment chart is displayed in which the primary colors of R, G, and B in which the gradation value is set as the reference balance value are adjacent to black (steps 11 and 12).
[0018]
Next, the R, G, and B luminances of the monitor are adjusted by the adjustment volume to the maximum luminance level at which the boundary line with black cannot be discriminated for each primary color as a unit, and the reference point is adjusted (step 13).
[0019]
Specifically, the chart of FIG. 4 (or the chart corresponding to the R, G, B3 colors corresponding to the chart of FIG. 4) set to the gradation value of the reference point is displayed on the monitor to be adjusted, and R, The brightness of each of G, B is changed using the adjustment volume of the monitor body, and each brightness of R, G, B is individually set to the maximum brightness level at which the boundary between Bk and the primary color charts of R0, G0, and B0 cannot be determined. (However, adjustments of R, G, and B are in no particular order.)
[0020]
In the present embodiment, a plurality of types of reference balance values may be prepared. In this case, in step 11 of the flowchart, a reference balance value corresponding to a target white balance can be selected from among them and set to each primary color displayed on the monitor.
[0021]
As the plurality of types of reference balance values, for example, when adjustment to the color temperature D50, D65, D93 or the like is considered, for D50, R0 = (22,0,0), G0 = (0,25,0) ), B0 = (0,0,37), and similarly for D65, R0 = (20,0,0), G0 = (0,16,0), B0 = (0,0,32), D93 For example, it can be assumed that R0 = (18,0,0), G0 = (0,16,0), and B0 = (0,0,30) are prepared.
[0022]
As described above in detail, the present embodiment enables the white balance of the monitor to be adjusted to be easily and quantitatively adjusted by visual evaluation of the adjustment chart without using a measuring device.
[0023]
According to the present embodiment, a reference balance value for R, G, and B is set in advance, and each brightness level of R, G, and B is adjusted to the reference value by visual evaluation, so that the monitor white can be easily and quantitatively determined. The balance can be adjusted to a certain level. Therefore, an expensive measuring device or specialized knowledge is not required, and objective color adjustment can be easily and accurately performed.
[0024]
In addition, according to the present embodiment, the color monitor is adjusted to an accurate white balance once, and the reference balance value at that time is determined. Can be easily returned to.
[0025]
In addition, the present embodiment can be used for general users who want to see accurate colors on the Internet or a CD-ROM, or for simple monitor adjustment at a content production site.
[0026]
Next, a second embodiment according to the present invention will be described.
[0027]
In the present embodiment, as in the first embodiment, the reference balance value is determined in advance, and when adjusting the target monitor, the R, G, and B primary colors are applied to the monitor as the reference balance values R0, G0. And a plurality of charts in which pixel values are changed step by step centering on B0, and displayed adjacent to each black, the luminance of each primary color of the monitor is continuously increased and decreased, and the boundary line with black is The reference brightness level is adjusted to a first luminance level that cannot be determined in the reference chart in which the reference balance value is set, but can be determined in the first comparison chart that is one level higher than the reference chart. The basic flow of the operation procedure is the same as the flowchart of FIG.
[0028]
That is, when the monitor is adjusted, an adjustment chart in which a plurality of R charts whose gradation values are changed step by step with Bk and the reference balance value R0 as shown in FIG. Display on the target monitor for adjustment.
[0029]
For example, when the determined reference balance value is R0 = (20, 0, 0), the reference chart set to this value is centered in the direction of R-1, R-2, ... Rn. , R-1 = (15,0,0), R-2 = (10,0,0)..., R gradation value is decreased by 5 steps, R + 1, R + 2,. Also in the direction of R + n, R + 1 = (25,0,0), R + 2 = (30,0,0)... And the chart in which the R gradation value is similarly increased by 5 steps is adjusted. R brightness is displayed at the first brightness level displayed on the target monitor and the boundary between Bk and R0 cannot be determined using the adjustment volume, and the boundary with R1 (first comparison chart) one level higher than R0 can be determined. adjust. For G and B, a chart centered on the respective reference values G0 = (0, 16, 0) and B0 = (0, 0, 32) is displayed and adjusted in the same manner (however, R, G, The adjustment of B is in no particular order).
[0030]
In the present embodiment, for example, a plurality of reference balance values (for color temperatures D50, D65, D93, etc.) similar to those in the first embodiment are used for adjustment similar to that shown in FIG. A chart may be prepared. In this case, the adjustment can be made in the same manner by selecting and displaying a chart corresponding to the target white balance from among them in step 11 of the flowchart of FIG. .
[0031]
Next, a third embodiment according to the present invention will be described.
[0032]
In this embodiment, after adjusting the monitor to be adjusted to the first luminance level by the method of the second embodiment, the pixel value is divided into finer pixel values between the reference chart and the first comparison chart. One or more charts set in this way are displayed adjacent to black, and each brightness of R, G and B of the monitor is continuously increased and decreased, and the boundary line with black is set with a reference balance value. It is adjusted to a second luminance level that cannot be discriminated with the reference chart, but can be discriminated with the second comparison chart one level higher than the reference chart, and the same operation is repeated as necessary. Therefore, the operation procedure can be represented by the flowchart of FIG. 6, and corresponds to repeating step 24 one or more times.
[0033]
That is, the brightness of the monitor to be adjusted is adjusted by the method of the second embodiment, and the adjustment is repeated by dividing the value between R0 and R + 1 in the adjustment chart shown in FIG.
[0034]
For example, in the chart shown in FIG. 7, the gradation value between R0 = (20, 0, 0) and R + 1 = (25, 0, 0), which is one level above, is 5 steps. Therefore, as shown in FIG. 10, in the next stage, R01 + 1 = (22,0) from R01 = (20,0,0) to R01 + 1, R01 + 2,..., R01 + n. , 0), R01 + 2 = (24,0,0)..., A chart with the R gradation value increased by 2 steps is displayed on the adjustment monitor, and the boundary between Bk and R01 can be discriminated. First, the R brightness is adjusted to a second brightness level at which the boundary with R01 + 1 (second reference chart), which is one step higher than R01 (reference chart), can be determined.
[0035]
If there is further necessity, in the next stage, R02 + 1 = (21,0) from R02 = (20,0,0) to R02 + 1, R02 + 2,... R02 + n. , 0), R02 + 2 = (22,0,0),..., A chart in which the R gradation value is increased step by step is displayed on the adjustment monitor, and the boundary between Bk and R02 is discriminated. The R luminance is adjusted to the third luminance level that cannot be determined and the boundary with R02 + 1 that is one step higher than R02 can be determined.
[0036]
Similarly, for G and B, a chart centering on the reference balance values G0 and B0 is displayed on the adjustment monitor, and the adjustment is repeated.
[0037]
According to the present embodiment, the step width is reduced in this way, and the chart is prepared hierarchically according to the required adjustment accuracy, monitor gradation expression performance, etc. Can be adjusted with high accuracy.
[0038]
Although the present invention has been specifically described above, the present invention is not limited to that shown in the above embodiment, and various modifications can be made without departing from the scope of the invention.
[0039]
For example, in the above-described embodiment, the case where each primary color is represented by an 8-bit gradation value is shown, but the present invention is not limited to this.
[0040]
Also, the method for determining the reference balance value is not limited to that shown in the embodiment.
[0041]
【The invention's effect】
As described above, according to the present invention, it is possible to easily and accurately perform objective color adjustment without requiring an expensive measuring device or specialized knowledge.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining the principle of the present invention. FIG. 2 is another diagram for explaining the principle of the present invention. FIG. 3 is a flowchart showing an outline of an operation procedure according to the first embodiment. 4 is an explanatory diagram illustrating an adjustment chart applied to the first embodiment. FIG. 5 is an explanatory diagram illustrating an adjustment chart applied to the second embodiment. FIG. 6 is a flowchart illustrating an outline of an operation procedure according to the third embodiment. FIG. 7 is an explanatory diagram showing an adjustment chart applied to the third embodiment.

Claims (6)

When the R, G, and B primary colors are displayed adjacent to black on a monitor with adjusted white balance, the maximum pixel value that cannot be distinguished from black in units of each primary color is the reference balance value for each primary color. Pre-determined
Where appropriate, the primary color set as the reference balance value is displayed on the same monitor adjacent to black, and the luminance of each primary color of the monitor is set to the maximum luminance level at which the boundary line with black cannot be distinguished for each primary color. A monitor adjustment method characterized by adjusting. In claim 1,
A monitor adjustment method comprising: preparing a plurality of types of reference balance values, selecting a reference balance value corresponding to a target white balance from the plurality of types, and setting each of the primary colors displayed on the monitor. In claim 1,
When adjusting the monitor, the brightness of each primary color of the monitor is continuously increased or decreased to adjust to a maximum brightness level at which a boundary line with black cannot be distinguished. In claim 1,
When adjusting the monitor, each primary color is displayed on the monitor as a plurality of charts in which pixel values are changed step by step with the reference balance value as the center, each adjacent to black,
The luminance of each primary color of the monitor is continuously increased or decreased, and the boundary line with black cannot be determined on the reference chart in which the reference balance value is set,
A monitor adjustment method, wherein the first brightness level that can be discriminated in the first comparison chart one level above the reference chart is adjusted. In claim 4,
Prepare multiple charts with pixel values changed step by step around the reference balance value, and select and display the chart corresponding to the target white balance from among them. A monitor adjustment method characterized by the above. In claim 4 or 5,
After the adjustment to the first luminance level, one or more charts set by dividing the pixel values into finer pixel values are displayed adjacent to black between the reference chart and the first comparison chart. ,
The brightness of each primary color of the monitor is continuously increased or decreased, and the boundary line with black cannot be determined in the reference chart in which the reference balance value is set,
Adjust each to a second luminance level that can be discriminated in the second comparison chart one level above the reference chart,
A monitor adjustment method characterized by repeating the same operation as necessary.

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