JP2013190449A - Video display device, video signal converting device, and method - Google Patents

Abstract

Color conversion suitable for video characteristics of a two-dimensional video and a three-dimensional video is set when color-converting an input video signal.
In addition to the R primary color point, the G primary color point, and the B primary color point, in the (x, y) chromaticity diagram, the R primary color point, the G primary color point, and a primary color point different from the B primary color point. PDP 105 having extended primary color point, input / output IF unit 101 for inputting video signal, and R primary color point, G primary color point, B primary color point, and extended primary color point based on the input video signal A signal processing unit 102 for generating an extended color signal, and a mode acquisition unit 203 for setting the video signal to the PDP 105 in a three-dimensional mode or a two-dimensional mode. The signal processing unit 102 includes: In the three-dimensional mode, the extended color signal is generated using a first color conversion method. In the two-dimensional mode, the second color conversion method different from the first color conversion method is used. Generate extended color signals.
[Selection] Figure 1

Description

  The present invention relates to a self-luminous display device that performs color conversion on an input video signal composed of RGB primary color points and displays the video signal on a self-luminous display.

  With the recent development of video technology, display devices have been developed to provide viewers with 3D perceived video (3D video). In many cases, the display device displays an image including a left eye frame image to be viewed with the left eye and a right eye frame image to be viewed with the right eye. The display device transmits a synchronization signal synchronized with the display of the frame image of the video. The user wears a dedicated eyeglass device for viewing 3D video. The eyeglass device performs a stereoscopic assistance operation for assisting viewing of the video based on the synchronization signal transmitted from the display device. While the display device displays the left eye frame image, the eyeglass device reduces the amount of light reaching the viewer's right eye and increases the amount of light reaching the viewer's left eye. Further, while the display device displays the right eye frame image, the spectacle device reduces the amount of light reaching the viewer's left eye and increases the amount of light reaching the viewer's right eye. Thus, the viewer perceives the image displayed by the display device in three dimensions. Normally, the left eye frame image and the right eye frame image are expressed using three primary colors of red, green, and blue, as in a normal two-dimensional image.

  Although not related to three-dimensional display, a technique related to a liquid crystal display in which the color reproduction range is expanded more than the three primary colors by using four primary colors in which yellow is added in addition to the usual three primary colors of red, green and blue is disclosed. . (Patent Document 1, Patent Document 2)

JP 2001-209047 A International Publication No. 2007/148519

  In a self-luminous device that emits light using a phosphor or the like such as a PDP display, afterglow characteristics differ depending on the type of phosphor. In a display that performs three-dimensional display in a time-division manner by the frame sequential method, the long afterglow of the green phosphor is actually a cause of crosstalk.

  In order to reduce crosstalk in three-dimensional display, four-color display with a fourth color using a phosphor with little afterglow can be considered. In this case, the three-color signal is color-converted into a four-color signal so that the amount of green used is reduced as much as possible. As a result, it is conceivable to reduce crosstalk.

  However, reducing afterglow to reduce crosstalk is not so important for a display when performing normal two-dimensional display. On the contrary, there is a problem that the fourth color cannot be used, such as reducing the light emission efficiency by reducing the crosstalk and lowering the color reproducibility.

  The present invention has been made to solve such a problem, and when color conversion is performed on an input video signal, color conversion suitable for each video characteristic of the two-dimensional video and the three-dimensional video is set. It is an object of the present invention to provide a self-luminous display device that can be used.

  In addition to the R primary color point, the G primary color point, and the B primary color point, the self-luminous display device of the present invention includes the R primary color point, the G primary color point, and the B primary color point on the (x, y) chromaticity diagram. A self-luminous panel having an extended primary color point different from the primary color point, an input unit for inputting a video signal, and an R primary color point, a G primary color point, a B primary color point, and an extended based on the input video signal A signal processing unit that generates an extended color signal expressed using primary color points, and the video signal is displayed on the self-luminous panel as a three-dimensional video (hereinafter referred to as a three-dimensional mode) or a two-dimensional video And a display setting unit that sets whether to display the extended color signal using the first color conversion method in the three-dimensional mode. In the two-dimensional mode, a second color change different from the first color conversion method is generated. Wherein generating the extended color signals using the method.

  In this way, the self-luminous display device performs color conversion of the video signal using different color conversion methods when set to the three-dimensional mode and when set to the two-dimensional mode. Can do. Thereby, when displaying a video signal on a self-luminous panel, a video signal suitable for two-dimensional or three-dimensional video characteristics can be displayed.

  Preferably, in the first color conversion method, one of the signal values expressed by the G primary color point is reduced so that a signal value expressed by the G primary color point among signal values constituting the video signal becomes small. This is a color conversion method in which a part is expressed by a primary color point different from the G primary color point.

  In this way, when the video signal is color-converted in the three-dimensional mode, the usage amount of the G primary color point can be reduced. Thereby, a three-dimensional image with little crosstalk can be displayed on the self-luminous panel.

  Preferably, in the first color conversion method, a part of the signal value expressed by the G primary color point is set as the G primary color point so that the signal value expressed by the G primary color point becomes a minimum value. Is a color conversion method to express with different primary color points.

  In this way, when the video signal is color-converted in the three-dimensional mode, the usage amount of the G primary color point can be minimized. Thereby, a three-dimensional image with the least crosstalk can be displayed on the self-luminous panel.

  Preferably, the extended color generated by the first color conversion method when the first color conversion method and the second color conversion method are applied to the same video signal in the signal processing unit. The signal value of the G primary color point included in the signal is equal to or less than the signal value of the G primary color point included in the extended color signal generated by the second color conversion method.

  Thereby, when displaying a two-dimensional image, priority can be given to luminous efficiency and color reproducibility compared with the case of displaying a three-dimensional image.

  Preferably, the display setting unit sets the three-dimensional mode or the two-dimensional mode based on header information of the video signal.

  In this way, the three-dimensional mode or the two-dimensional mode can be set only by analyzing the header information of the video signal. Thus, the video signal can be converted using a suitable color conversion mode.

  Preferably, the self-luminous display device further includes a receiving unit that receives an operation signal from a user, and the display setting unit is based on the operation signal received by the receiving unit. Alternatively, the two-dimensional mode is performed.

  In this way, the two-dimensional mode or the three-dimensional mode can be set by a user operation. Thereby, the user can select a color conversion mode that is intentionally applied to the video signal.

  According to the self-luminous display device of the present invention, when color conversion is performed on an input video signal, it is possible to set color conversion suitable for the video characteristics of the two-dimensional video and the three-dimensional video.

The figure which shows the specific structure of the PDP television 1 in this embodiment. The figure which represented the color reproduced using three primary color points of R, G, and B in this embodiment on the (x, y) chromaticity diagram Functional block diagram of the signal processing unit 102 in the present embodiment The figure which shows the example which reproduces 4 colors with the conversion characteristic of the said 1st conversion mode, using Y color as an extended color in this embodiment. The figure which shows the color gamut which can be reproduced in this embodiment The figure for demonstrating the modification of the color gamut expansion mode in this embodiment. The figure which shows arrangement | positioning of the fluorescent substance which comprises each color in PDP105 in this embodiment. Flowchart up to conversion of video signal to extended color signal in this embodiment The figure for demonstrating the modification at the time of using C (cyan) primary color point instead of Y primary color point in this embodiment. The figure for demonstrating the modification at the time of using W (white) primary color point instead of Y primary color point in this embodiment.

<1. PDP display device and its peripheral devices>
Hereinafter, the PDP television 1 according to the first embodiment will be described with reference to the drawings.

  FIG. 1 is a diagram showing a specific configuration of the PDP television 1. As shown in FIG. 1, a PDP television 1 is connected to a recorder device 2, an antenna 3, and an SD card 4. The PDP television 1 inputs video signals output from the recorder device 2, the antenna 3, and the SD card 4. Then, this video signal is processed and displayed as a video on a display provided in the PDP television 1.

  Specifically, the PDP television 1 includes an input / output IF unit 101, a signal processing unit 102, a buffer memory 103, a flash memory 104, and a PDP 105 as shown in FIG.

  The input / output IF unit 101 is an interface that enables connection between the recorder device 2 and the SD card 4. The input / output IF unit 101 can exchange control signals and video signals with the signal processing unit 102. The input / output IF unit 101 transmits a signal received from the recorder device 2 or the SD card 4 to the signal processing unit 102. Further, the input / output IF unit 101 transmits the signal received from the signal processing unit 102 to the recorder device 2 or the SD card 4. For example, the input / output IF unit 101 can be realized by an HDMI connector, an SD card slot, or the like. Further, the input / output IF unit 101 may be configured as a device having the function of the input / output IF unit 101 and the function of the recorder device 2. In FIG. 1, one block is illustrated as the input / output IF unit 101. However, a card slot for the SD card 4 and a connector for the recorder device 2 may be provided. In short, the signal processing unit 102 only needs to realize an interface with an external recording apparatus.

  The signal processing unit 102 controls each unit of the PDP television 1. Further, the signal processing unit 102 may decode the video signal output from the input / output IF unit 101. Further, the signal processing unit 102 performs image processing on the video signal and converts it into a display signal that can be displayed on a monitor. The signal processing unit 102 may be configured with a microcomputer or a hard-wired circuit.

  The buffer memory 103 is used as a work memory when the signal processing unit 102 performs signal processing. The buffer memory 103 can be realized by a DRAM, for example.

  The flash memory 104 stores a program executed by the signal processing unit 102.

  The PDP 105 displays the display signal output from the signal processing unit 102 as a display screen. For example, the PDP 105 can be realized by a self-luminous display such as a plasma display panel. In addition to the R primary color point, the G primary color point, and the B primary color point, the PDP 105 is different from the R primary color point, the G primary color point, and the B primary color point on the (x, y) chromaticity diagram. The extended primary color point (hereinafter referred to as extended color) is provided. Hereinafter, for convenience of explanation, a configuration using one extended color will be described. Note that the extended color is not limited to one color, and a configuration using two or more extended colors may be used. For example, as the extended color, a yellow primary color point, a cyan primary color point, or a white primary color point can be considered.

  The tuner 106 receives the broadcast wave received by the antenna 3. The tuner 106 transmits a video signal having a specific frequency designated by the signal processing unit 102 to the signal processing unit 102. As a result, the signal processing unit 102 can process a video signal of a specific frequency included in the broadcast wave and display it on the PDP 105.

<1-1. Regarding extended colors>
Hereinafter, the extended color will be described.

  For example, a plasma display panel that is a self-luminous display discharges plasma for each pixel. Ultraviolet rays are generated by this plasma discharge. Each primary color point emits light when the generated ultraviolet light excites each color phosphor. Afterglow occurs when each primary color point emits light. Afterglow is light emission of the phosphor remaining after the generation of ultraviolet rays stops. The afterglow time is attributed to the material constituting the phosphor. That is, the afterglow time varies depending on the color of the phosphor. Of the phosphors used in the plasma display panel, the afterglow time of the B color phosphor is short and is 1 msec or less. On the other hand, the afterglow time of the G color phosphor is very long and is about 10 msec. The afterglow time of the R color phosphor is a time between the afterglow time of the B color phosphor and the afterglow time of the G color phosphor. Therefore, reducing the amount of light emitted by the G-color phosphor having a long afterglow time is effective for improving the afterglow characteristics of the plasma display panel and reducing crosstalk.

  FIG. 2 is a (x, y) chromaticity diagram showing colors reproduced using the three primary color points of the R primary color point, the G primary color point, or the B primary color point. When the R color is expressed by (R, G, B) = (1, 0, 0), the G color is (0, 1, 0) and the B color is (0, 0, 1). The secondary colors Y (yellow), C (cyan), and M (magenta) are Y color = (1, 1, 0), C color = (0, 1, 1), M color = (1, 0, 1), and the W color (white) as the tertiary color is W color = (1, 1, 1). Here, attention is paid to the usage amount of the G primary color point mainly related to the afterglow time. In this case, the usage amount of the G primary color point is the maximum value 1 for the G color, the Y color, the W color, and the C color.

  Further, FIG. 2 represents the usage amount of the G primary color point as a shaded density. In other words, the dark portion in FIG. 2 uses a large amount of the G primary color point. Further, in the light-colored portion in FIG. 2, the usage amount of the G primary color point is small. As shown in FIG. 2, the usage amount of the G primary color point in the region surrounded by G-C-W-Y takes the maximum value 1, so that the afterglow is the largest.

  Now consider the W color. Most of the colors that represent video signals are low-saturation colors. That is, most of the colors representing the video signal are colors near the W color. In the image signal, the usage amount of the G primary color point is high although the frequency of appearance of colors near the W color is high. Actually, the use amount of the G primary color point is the maximum value 1 in the color near the W color. For this reason, there is much crosstalk due to afterglow, and the quality of the three-dimensional display is degraded.

  Therefore, in order to reduce the usage amount of the G primary color point, the PDP television 1 introduces a primary color point different from the R primary color point, the G primary color point, or the B primary color point. The PDP television 1 performs signal processing on the video signal so as to reduce crosstalk when the video signal is three-dimensionally displayed. In addition, by adding an extended color, the PDP 105 may obtain performance improvements other than afterglow reduction. Therefore, when the PDP television 1 displays the video signal two-dimensionally, the PDP 105 performs signal processing on the video signal so that two-dimensional display performance (to be described later) other than the reduction in afterglow is improved.

<1-2. Regarding Configuration of Signal Processing Unit 102>
Hereinafter, a specific configuration of the signal processing unit 102 will be described with reference to the drawings.

  FIG. 3 is a functional block diagram of the signal processing unit 102.

  As shown in FIG. 3, the signal processing unit 102 includes an RGB conversion unit 201, an inverse gamma conversion unit 202, a mode acquisition unit 203, a four-color conversion unit 204, and a driver 205.

  The RGB conversion unit 201 converts the video signal composed of the luminance signal Y and the color difference signals Cb, Cr input from the input / output IF unit 101 into an RGB signal composed of R color, G color, and B color. .

  The inverse gamma conversion unit 202 performs inverse gamma conversion on the RGB signal output from the RGB conversion unit 201 and outputs the converted RGB signal to the four-color conversion unit 204.

  Whether the mode acquisition unit 203 processes the video signal as a two-dimensional signal based on meta information such as header information of the video signal output from the RGB conversion unit 201 and displays it on the PDP 105 (hereinafter referred to as a two-dimensional mode). Whether to process the signal with a three-dimensional signal and display it on the PDP 105 (hereinafter referred to as a three-dimensional mode) is set. For example, when the video signal has several bits of flag information indicating a three-dimensional signal, the mode acquisition unit 203 performs determination based on the flag information. That is, the mode acquisition unit 203 detects the three-dimensional mode when the flag information is ON. Conversely, when the flag information is OFF, the mode acquisition unit 203 detects the video signal as a two-dimensional mode. The mode acquisition unit 203 may be configured to have a receiver function for receiving an operation signal from the user via wireless such as infrared rays and set from the received operation signal. Further, when a video signal and command information indicating whether or not the video signal is a three-dimensional signal are input from the recorder device 2, a configuration in which the setting is based on the command information may be used. Furthermore, it is also possible to automatically determine from the content of the video signal by analyzing the video content peculiar to the three-dimensional signal, such as a side-by-side 3D video format.

  Note that the mode acquisition unit 203 outputs setting information indicating the detection result to the four-color conversion unit 204.

  The four-color conversion unit 204 converts the RGB signal output from the inverse gamma conversion unit 202 into an extended color signal using the R primary color point, the G primary color point, the B primary color point, and the extended color. When converting to an extended color signal, the mode acquisition unit 203 changes the conversion method from the RGB signal to the extended color signal based on the setting information output from the mode acquisition unit 203. When determining that the three-dimensional mode is based on the setting information, the four-color conversion unit 204 converts the RGB signal in the first color conversion mode. Further, when the four-color conversion unit 204 determines that the two-dimensional mode is based on the setting information, the four-color conversion unit 204 converts the RGB signals in the second color conversion mode. Details of the first color conversion mode and the second color conversion mode will be described later.

  The four-color conversion unit 204 outputs the generated extended color signal to the driver 205.

  The driver 205 converts the extended color signal output from the four-color conversion unit 204 into a display signal that can be displayed on the PDP 105.

<1-3. Color conversion mode>
Hereinafter, the first color conversion mode and the second color conversion mode in the four-color conversion unit 204 will be described with reference to the drawings.

  The four-color conversion unit 204 has a function of converting the RGB signal input from the inverse gamma conversion unit 202 into a color signal expressed by the four primary color points of the PDP 105. The four-color conversion unit 204 applies different color conversion methods for the three-dimensional mode and the two-dimensional mode.

  Hereinafter, for convenience of explanation, a case where the R primary color point, the G primary color point, the B primary color point, and the Y primary color point are used as the four primary color points will be described. The Y primary color point to be applied is a primary color point located between the G primary color point and the R primary color point for convenience of explanation. Further, the RGB signal output from the inverse gamma conversion unit 202 is converted into four colors by the four-color conversion unit 204, and the resulting color signal is defined as an R′G′B′Y signal.

<1-3-1. First color conversion mode>
The first color conversion mode is a color conversion mode for reducing crosstalk when a video signal is three-dimensionally displayed on the PDP 105. Hereinafter, the first color conversion mode will be described with reference to the drawings.

  The primary purpose of the first color conversion mode is to reduce crosstalk caused by the afterglow of the video signal displayed on the PDP 105.

  Hereinafter, the characteristics of the first conversion mode will be described.

  Here, some Y phosphors constituting the Y primary color point have a short afterglow time like the B phosphor. Therefore, when used for the phosphor of the PDP 105, a very short afterglow characteristic can be realized.

  The first conversion mode is a mode for reducing the usage amount of the G primary color point by replacing the G primary color point with the Y primary color point. In this color conversion mode, the four-color conversion unit 204 converts the RGB signal into four colors based on the following conversion formula as an example.

(Equation 1) Y = min (R, G)
(Equation 2) R ′ = R−Y
(Equation 3) G ′ = G−Y
(Equation 4) B ′ = B
This conversion characteristic minimizes the use amount of the G primary color point for the required reproduction color. In the above formula, the configuration in which the usage amount of the G primary color point is minimized has been described, but a configuration in which a part of the G primary color point is replaced with the Y primary color point may be employed.

  FIG. 4 is a diagram illustrating an example in which four-color reproduction is performed in the first conversion mode using the Y primary color point as an extended color. The shaded area in FIG. 4 is the same as that in FIG. 2, and indicates the usage amount of the G primary color point. The numerical values shown to the right of each color are the usage level of the R primary color point, the G primary color point, or the B primary color point and the usage level of the Y primary color point. For example, the Y color is (000-1). Therefore, the usage rate of the G primary color point, which was the usage rate 1 in FIG. For the W color, the usage rate of the G primary color point, which was 1 in FIG. Therefore, it can be seen that the G primary color point usage rate can be reduced.

  In FIG. 4, the amount of use of the G primary color point is a limited color between the G color and the C color (corresponding to the region 401 in FIG. 4). That is, in FIG. 2, the amount of G primary color point used in the entire color space can be reduced compared to the amount of G primary color point used for a wide range of colors surrounding G-C-W-Y. I understand that.

  In addition, the color of the region 402 shown in FIG. 4 (corresponding to G color with high saturation) hardly exists in the object color of the natural image. Therefore, these colors are rarely required in a normal video. Therefore, the influence of the large usage amount of the G primary color point in the region 401 is small. On the other hand, the appearance ratio of colors close to monochrome with low saturation is high in normal video signals. For this reason, the fact that the usage rate of the G primary color point when reproducing the W color is 0 has a great influence on crosstalk reduction in normal video display.

  Therefore, when four-color conversion is performed in the first conversion mode, image quality deterioration due to crosstalk is greatly reduced, and image quality in three-dimensional display can be improved. In addition, since the obstruction factor of stereoscopic vision due to crosstalk is reduced, not only image quality but also easy-to-see 3D image quality can be realized.

<Modification 1>
Modification 1 that further enhances the effect of the first conversion mode in the present embodiment will be described. In the first conversion mode, there is a region (region 401 in FIG. 4) where the amount of G primary color point used is large. The color of this area is rarely input as a video signal for a natural image. However, it is input in the image of a luminescent material such as CG, animation or neon sign, or a test pattern image.

  Rather than correctly reproducing the colors of the region 401 in these videos, it may be better in view of the image quality of the three-dimensional display to reduce the crosstalk even if the saturation of these colors is slightly reduced. This determination varies depending on the degree of afterglow of the G primary color point.

  In this modified example, for high quality 3D image display, it is more important to reduce crosstalk for colors with a lot of crosstalk (colors between G and C) than to reproduce vivid colors. In accordance with the determination, the following processing is performed as an example in addition to the four-color conversion in the first conversion mode.

  When the darkest shaded area (the color of the area on the left side of the straight line L) in FIG. 4 is input, the color gamut is changed to the color on the right side of the straight line L by a known technique such as color gamut conversion (Gamut conversion). Perform color conversion to limit As a result, the saturation of these colors slightly decreases, but the crosstalk in the color with the most crosstalk can be reduced. Thus, when the video signal is displayed as a 3D video, the quality of the 3D video can be improved. The color gamut conversion can also be realized by a simple method of clipping a signal.

<1-3-2. Second color conversion mode>
The second color conversion mode is a color conversion mode that is used to improve the performance when the extended color is two-dimensionally displayed. Hereinafter, the second color conversion mode will be described with reference to the drawings.

  The second color conversion mode includes at least (1) a conversion mode for improving luminous efficiency and reducing power consumption (hereinafter referred to as an efficiency improvement mode), and (2) widening the color gamut as performance improvement during two-dimensional display. Conversion mode for improving color reproducibility (hereinafter referred to as a color gamut expansion mode), and (3) a conversion mode for reducing spatial brightness unevenness when a video signal is displayed on the PDP 105 (hereinafter referred to as brightness unevenness reduction mode). Included). In any case, the second color conversion mode is different from the first conversion mode in that the main purpose is not to reduce crosstalk by shortening the afterglow time. This is because the afterglow time of the phosphor has little influence on the image quality in the two-dimensional signal.

  Hereinafter, the three conversion modes will be described with reference to the drawings.

<1-3-2-1. Efficiency improvement mode>
Hereinafter, the efficiency improvement mode will be described. For convenience of explanation, consider the case where the Y primary color point is used as the extended color. As the Y primary color point, the afterglow time is short, but the light emission efficiency may be poor.

  In this case, as the second color conversion mode, it is desirable that the four-color conversion unit 204 refrain from using the Y primary color as much as possible. As an example of this, a configuration of the four-color conversion unit 204 that reproduces a desired color using only the R, G, and B primary color points without using the Y primary color point can be considered. With this configuration, it is possible to reduce power consumption.

<1-3-2-2. Color gamut expansion mode>
Hereinafter, the color gamut expansion mode will be described.

  As an example of the color gamut expansion mode, there is the cancellation of the color gamut reduction described in the first modification of the first color conversion mode. In the first color conversion mode, the reproduction of the color gamut located to the left of the straight line L in FIG. 4 is limited in order to reduce the usage rate of the G primary color point and reduce the crosstalk.

  However, in the two-dimensional display in which the phosphor afterglow time has little influence on the image quality, expanding the color gamut is more effective in improving the image quality than reducing the afterglow.

  Therefore, in the present color gamut expansion mode, for example, the color gamut conversion is performed so that the color gamut located to the left of the straight line L in FIG. 4 is converted into the right region. Furthermore, it is possible to increase the saturation of the right color of the straight line L and convert it to the left of the straight line L.

  Further, when the Y primary color point on the straight line connecting the G primary color point and the R primary color point is used as the extended color, the chromaticity of the G primary color point is shifted to the left on the (x, y) chromaticity diagram than before. It is effective to change the phosphor to a G ′ primary color point having a chromaticity value. Since the phosphor constituting the G primary color point is a blend of a plurality of phosphors, the chromaticity value can be easily changed by changing the blending ratio. The color gamut that can be reproduced in this case is an area surrounded by a solid line shown in FIG. Instead of the color gamut between the Y color and the G color being slightly narrowed, the wide color gamut between the G ′ color and the B color is expanded. In addition, the area | region enclosed with the dotted line of Fig.5 (a) shows the color gamut at the time of using the conventional primary color point.

  The meaning of the color gamut expansion will be described with reference to FIG. The DCI color gamut, which is a wide color gamut color space used in digital cinema, corresponds to the color gamut on film. The feature is that the G primary color point is from the right and red-yellow is rich. The G primary color point in FIG. 5B represents the DCI primary color point. On the other hand, the color gamut of AdobeRGB, which is a wide color gamut color space used in photographs, is represented by R-G'-B (the difference between B and R is small). This color space is characterized by a wide color reproduction range of an emerald (blue green) region that can represent a photograph. In any case, the bright green color that is the color of the region 501 shown in FIG. 5B does not exist in the natural world and does not exist as an object color. Therefore, it is not important when generating a color signal. Therefore, the RG'BY primary color point, in which Y color is added as an extended color and G is changed to G ', is a feature that is rich in red-yellow that is a feature of the DCI gamut and a feature that is a feature of the AdobeRGB gamut. It also has an emerald color area. Therefore, it is possible to effectively perform color gamut expansion when an extended color is added.

  Note that when the C color is used as the extended color, a C color having a chromaticity outside the straight line connecting GB can be realized. Therefore, as shown in FIG. 5C, a wide color gamut having both the features of the DCI color gamut and the AdobeRGB color gamut can be provided.

<Modification 1>
Next, a modification of the color gamut expansion mode will be described.

  The first color conversion mode aims to reduce crosstalk by reducing the amount of G primary color point used. At that time, it was described that the usage amount of the G primary color point can be reduced to 0 for the Y color and the W color. On the other hand, in the second color conversion mode used in the two-dimensional display, it is not necessary to reduce the usage amount of the G primary color point.

  In this color conversion mode, the usage amounts of the G primary color point and the R primary color point are used for the color conversion characteristics in the first color conversion mode for colors in the color gamut of the GYR region centering on the Y color. It is characterized by being used in excess of the usage amount of the G primary color point and R primary color point obtained by the mathematical formulas 2 and 3. This makes it possible to increase the luminance of the color gamut of the area 601 in FIG. This color gamut expansion effect will be described in more detail. FIG. 6B illustrates a state in which the hue direction (BWY direction) of the thick double arrow line in FIG. 6A is viewed from the top including the luminance. Here, the Y color and the Y primary color point by the R primary color point + G primary color point are the same.

  The B primary color point has low luminance, and the Y primary color point has high luminance. When the above color conversion mode is used, the color gamut of the Y color extends in the luminance direction up to the Y ′ color. Of the expanded color gamut, the hatched area 602 can be used effectively for color reproduction. For example, the color of this hue is a color with high luminance such as yellow, skin color, orange, or bright yellow. When this color is adjusted in the direction of increasing the luminance or the direction of increasing the saturation by color adjustment processing such as gradation correction or saturation expansion, the color is saturated as indicated by an arrow 603 in the figure because there is little room for luminance. For example, when a person's face is exposed to light, the color is saturated and becomes yellow. However, if the color gamut of the area 602 is sufficient for this color gamut, a color brighter than the W color can be reproduced with the flesh color hue. Therefore, high-quality color expression is possible. Further, the color gamut color is an area that can be expressed in the extended color space xvYCC, and can be input in an image obtained by photographing a yellow neon sign or the like. Even in this case, display is possible without being saturated.

  Here, for simplicity of explanation, Y = R + G is used, but it goes without saying that when it is out of this relationship, the conversion functions become complicated and functions similarly.

<1-3-2-2-3. Uneven brightness reduction mode>
Hereinafter, the luminance unevenness reduction mode will be described with reference to the drawings.

  FIG. 7 is a diagram showing the arrangement of phosphors constituting each color in the PDP 105.

  As shown in FIG. 7A, in the PDP 105, it is desirable that the G primary color point and the Y primary color point at which the viewer can easily perceive luminance are arranged at equal intervals. As a result, it is difficult to visually perceive uneven brightness, and a smooth video signal with less unevenness can be displayed on the PDP 105.

  Here, let us consider a case where the usage amount of the G primary color point is reduced and the Y primary color point is used as much as possible. In this case, for the visually important W color, (R ′, G ′, B ′, Y) = (0, 0, 1, 1). Therefore, the usage amount of the G primary color point having a large influence on the luminance is reduced. As a result, the influence on the luminance depends on the Y color, and as shown by the hatching in FIG. 7A, the luminance frequency becomes a quarter of the sub-pixel frequency.

  Further, consider the case where the Y primary color point is not used and reproduction is performed using only RGB signals. In this case, in the visually important W color display, (R ′, G ′, B ′, Y) = (1, 1, 1, 0). For this reason, in the arrangement of FIG. 7B, the amount of Y color that has a large influence on the luminance is reduced. As a result, the influence on the luminance depends on the G color, and the luminance frequency is a quarter of the sub-pixel frequency.

  In the above two cases, the luminance band is a quarter of the subpixel frequency. Therefore, in reproduction of W color, which is important for image quality, there is no expected luminance unevenness reduction effect by the arrangement of FIG. 7A or FIG. 7B, and white stripes are easily noticeable.

  Thus, in the luminance unevenness reduction mode, it is desirable to perform conversion that keeps the usage amounts of the G color and the Y color approximately uniform. An example of this conversion is given by

(Equation 5) Y = min (R, G / 2)
(Equation 6) R ′ = R−Y
(Equation 7) G ′ = G−Y
(Equation 8) B ′ = B
When this luminance unevenness reduction mode is used, in the visually important W color display, (R ′, G ′, B ′, Y) = (1/2, 1/2, 1, 1/2) Become. Therefore, in the arrangement shown in FIG. 7C, the Y and G colors that have a large influence on the luminance emit light in equal amounts. As a result, the luminance frequency can be increased to half the sub-pixel frequency, and a high-quality two-dimensional image with little unevenness is displayed.

  In addition, there is a technology that can express a pixel in which three primary color points or four primary color points are grouped using sub-pixels. This technique aims to realize luminance resolution exceeding the resolution.

  This technology inputs a video signal having a resolution higher than that which can be expressed by the pixel, the luminance component of the video signal passes through about twice the pixel frequency, and the color difference component is band-limited below the pixel frequency. This is a technique for converting and displaying RGB signals. In this technique, since the color representation requires a set of three colors, the representation remains below the pixel frequency. However, with respect to luminance expression, R, G, and B are treated as independent ones, and this is a technique aiming at expression with resolution exceeding the pixel frequency.

  However, when applied to an RGB stripe display with three primary colors in reality, as described above, the G pixel has a low luminance expression power even though the luminance expression power is high. It was difficult to improve the resolution as desired.

  On the other hand, the subpixel processing technique is applied to the display using the extended color (here, the Y primary color point) shown in FIG. Apply the color conversion. As a result, G pixels and Y pixels having high luminance expression capability exist in the pixels expressed by the four primary color points, so that a double luminance resolution can be obtained satisfactorily, and vertical stripes and color blurs are relatively high. I'm not sorry.

  Thus, the luminance unevenness reduction mode in the two-dimensional display has high affinity with the subpixel processing technology.

  Therefore, since the 3 primary color points are increased to 4 primary color points, the pixel density is not increased, and the subpixel processing technique can compensate for the resolution being reduced to 3/4.

  The four-color conversion characteristics in the “efficiency improvement mode”, “color gamut expansion mode”, and “brightness unevenness reduction mode” have been specifically described as the “second color conversion mode” used in the two-dimensional display. However, the “second color conversion mode” is not limited to the color conversion described above. For example, consider using three-dimensional glasses in a three-dimensional display. In this case, color reproduction and gradation reproduction are changed by the three-dimensional glasses. Therefore, when a display optimized for three-dimensional display is used, white balance characteristics, color conversion characteristics, gradation characteristics, and the like are different in the two-dimensional display mode. Therefore, it is reasonable to perform these conversions in the second color conversion mode.

<2. Operation of PDP TV 1>
<2-1. 4-color conversion operation of input video signal>
Hereinafter, the video signal conversion operation in the PDP television 1 will be described with reference to the drawings.

  FIG. 8 is a flowchart until the video signal is converted into the extended color signal. Hereinafter, for convenience of explanation, it is assumed that a YCbCr video signal is input to the input / output IF unit 101 from the recorder device 2.

  (S801) When a video signal is input from the input / output IF unit 101, the RGB conversion unit 201 converts the video signal into an RGB signal. The converted RGB signal is output to the inverse gamma conversion unit 202.

  (S802) When an RGB signal is input from the RGB conversion unit 201, the inverse gamma conversion unit 202 performs inverse gamma conversion on the RGB signal. Then, the inverse gamma conversion unit 202 outputs the RGB signal obtained by the inverse gamma conversion to the four-color conversion unit 204.

  (S803) Next, the mode acquisition unit 203 detects meta information added to the video signal input from the input / output IF unit 101. And the mode acquisition part 203 detects the flag information which shows whether it is a three-dimensional mode from the detected meta information. When the flag information is ON, setting information for setting the three-dimensional mode is output to the four-color conversion unit 204. Then, the process proceeds to S804. On the other hand, when the flag information is OFF, setting information for setting the two-dimensional mode is output to the four-color conversion unit 204. In this case, the process proceeds to S806.

  (S804) When setting information for setting the three-dimensional mode is input from the mode acquisition unit 203, the four-color conversion unit 204 performs four-color conversion on the RGB signal subjected to inverse gamma conversion in the first color conversion mode, and expands the color. Generate a signal. Then, the generated extended color signal is output to the driver 205.

  (S805) When the extended color signal is input from the four-color conversion unit 204, the driver 205 generates a display signal that can be displayed on the PDP 105 based on the extended color signal. Then, the driver 205 outputs the generated display signal to the PDP 105.

  (S806) On the other hand, when setting information for setting the two-dimensional mode is input from the mode acquisition unit 203, the four-color conversion unit 204 performs four-color conversion on the RGB signal subjected to inverse gamma conversion in the second color conversion mode, Generate extended color signals. Then, the generated extended color signal is output to the driver 205.

  (S807) When a display signal is input from the driver 205, the PDP 105 displays an image that can be viewed by the viewer based on the display signal.

  In C3, the configuration has been described in which the mode acquisition unit 203 detects whether or not the mode is the three-dimensional mode from the flag information. However, the mode acquisition unit 203 may be configured to detect whether or not the mode is the three-dimensional mode based on an operation signal transmitted by the user in advance. The mode acquisition unit 203 may be configured to detect whether or not the mode is the three-dimensional mode based on the command information transmitted from the recorder device 2.

  In S806, the second color conversion mode may be configured such that the viewer can select one mode from the efficiency improvement mode, the color gamut expansion mode, and the luminance unevenness reduction mode.

<3. Effects according to extended colors>
<3-1. When C primary color point is used as extended color>
FIG. 9 shows a modification in which the C (cyan) primary color point is used instead of the Y primary color point. Again, for simplicity of explanation, it is assumed that the C primary color point has the same chromaticity value as that obtained by the G primary color point + B primary color point.

  As shown in FIG. 9, the usage amount of the G primary color point can be reduced as compared with the case where the three primary color points of RGB are used. Therefore, when the C primary color point with little afterglow is used, a high-quality three-dimensional image with little crosstalk can be displayed. Also, the point where the important W color crosstalk is small is the same as the case where the Y primary color point is used.

  In the two-dimensional display, it is possible to widen the color gamut of bright colors with C hue.

  Further, since the C color is also a color having a high contribution to luminance, the above-described luminance unevenness is the same as described above.

<3-2. When W primary color point is used as extended color>
FIG. 10 shows a modification in which a W (white) primary color point is used instead of the Y primary color point. Again, for simplicity of explanation, the W primary color point has the same chromaticity value as that obtained by the R primary color point + G primary color point + B primary color point.

  As shown in FIG. 10, the usage amount of the G primary color point is slightly increased as compared with the case of using the Y primary color point and the case of using the C primary color point. However, the use amount of the G primary color point can be reduced as compared with the display of the three primary color points constituting the RGB signal. As a result, a high-quality three-dimensional image with little crosstalk can be displayed. Also, the point where the important W color crosstalk is small is the same as the case where the Y primary color point is used.

  Further, by using the W primary color point, the brightness of the W color can be expanded in the two-dimensional display. Further, since the W color is also a color having a high contribution to luminance, the above-described luminance unevenness is the same as described above. Further, since the achromatic color can be expressed only by the W pixel, there is a possibility that the power efficiency can be maximized.

<Correspondence between this embodiment and the present invention>
The PDP television 1 is an example of the self-luminous display device of the present invention. The input / output IF unit 101 is an example of the input unit of the present invention. The signal processing unit 102, the buffer memory 103, and the flash memory 104 are examples of the signal processing unit of the present invention. The PDP 105 is an example of the self-luminous panel of the present invention.

<4. Summary>
In addition to the R primary color point, the G primary color point, and the B primary color point, the PDP television 1 in the present embodiment includes the R primary color point, the G primary color point, and the B primary color point on the (x, y) chromaticity diagram. PDP 105 having extended primary color points of different primary color points, input / output IF unit 101 for inputting a video signal, R primary color point, G primary color point, B primary color point, and extended primary color based on the input video signal A signal processing unit 102 that generates an extended color signal expressed using points, and the video signal is displayed on the PDP 105 as a three-dimensional video (hereinafter referred to as a three-dimensional mode) or as a two-dimensional video. (Hereinafter referred to as a two-dimensional mode) or a mode acquisition unit 203 for setting the signal processing unit 102, in the three-dimensional mode, the signal processing unit 102 uses the first color conversion method to output the extended color signal. And in 2D mode It may generate the extended color signal using a second color different conversion method and the first color conversion method.

  In this way, the PDP television 1 can appropriately change the method of generating the extended color signal depending on whether the input video signal is a two-dimensional signal or a three-dimensional signal. As a result, even when switching from the three-dimensional mode to the two-dimensional mode, it is possible to view a high-quality video signal in each display format.

  In the first color conversion mode according to the present embodiment, the signal value expressed by the G primary color point is reduced so that the signal value expressed by the G primary color point among the signal values constituting the video signal becomes small. A portion is expressed by a primary color point different from the G primary color point.

  Further, in the first color conversion mode in the present embodiment, a part of the signal value expressed by the G primary color point is changed to the G primary color point so that the signal value expressed by the G primary color point becomes the minimum value. Has a feature expressed by different primary color points.

  In this way, in the case of the three-dimensional mode, the signal processing unit 102 can reduce the usage amount of the G primary color point when the video signal is converted into the extended color signal. This makes it possible to reduce the influence of crosstalk even when the video signal has many G primary color points.

  Further, when the first color conversion mode and the second color conversion mode are applied to the same video signal in the signal processing unit 102 in the present embodiment, the extension generated in the first color conversion mode. The signal value of the G primary color point included in the color signal is less than or equal to the signal value of the G primary color point included in the extended color signal generated in the second color conversion mode.

  In this way, the usage amount of the G primary color point in the three-dimensional mode can be set to be equal to or less than the usage amount in the two-dimensional mode. As a result, it is possible to display the 3D video as a video signal with reduced crosstalk or the same performance, rather than simply displaying the extended color signal used in the 2D video display.

  Further, the mode acquisition unit 203 has a feature of performing the three-dimensional mode or the two-dimensional mode based on the header information of the video signal.

  In this way, the mode acquisition unit 203 can determine whether the video signal is a three-dimensional signal or a two-dimensional signal only by detecting meta information of the video signal. Thus, the color conversion mode applied to the RGB signal can be set without the four-color conversion unit 204 analyzing the RGB signal.

  Further, the PDP television 1 further includes a mode acquisition unit 203 that receives an operation signal from a user, and the mode acquisition unit 203 uses the three-dimensional mode or the mode acquisition unit 203 based on the operation signal received by the mode acquisition unit 203. The two-dimensional mode may be configured.

  In this way, the mode acquisition unit 203 can determine whether the video signal is a three-dimensional signal or a two-dimensional signal only by detecting the input operation signal. Thus, the determination can be made without analyzing the header information of the video signal in the mode acquisition unit 203.

<5. Other embodiments>
As mentioned above, although the form of this embodiment was demonstrated, this invention is not limited to this.

  For example, in the present embodiment, the configuration including the PDP 105 has been described. However, the present invention can also be realized as a color conversion device that does not include the PDP 105.

  In addition, this embodiment implement | achieves the color conversion method which uses each means which a self-light-emitting display device comprises as each step, and the integrated circuit and color conversion method provided with each means which a self-light-emitting display device comprises. It is also possible to provide a program that can be used.

  The video signal conversion program can be distributed via a recording medium such as a CD-ROM (Compact Disc-Read Only Memory) or a communication network such as the Internet.

  The integrated circuit can be realized as an LSI which is a typical integrated circuit. In this case, the LSI may be composed of one chip or a plurality of chips. For example, the functional blocks other than the memory may be configured with a one-chip LSI. Although referred to as LSI here, it may be called IC, system LSI, super LSI, or ultra LSI depending on the degree of integration.

  Further, the method of circuit integration is not limited to LSI, but may be realized by a dedicated circuit or a general-purpose processor, or an FPGA (Field Programmable Gate Array) that can be programmed after the LSI is manufactured, A reconfigurable processor that can reconfigure the connection and setting of circuit cells may be used.

  Further, if integrated circuit technology comes out to replace LSI's as a result of the advancement of semiconductor technology or a derivative other technology, it is naturally also possible to carry out function block integration using this technology. For example, it is considered possible to apply biotechnology.

  In addition, when the integrated circuit is formed, only the unit for storing data among the functional blocks may not be taken into the one-chip configuration but may be configured separately.

  The self-luminous display device according to the present invention can be applied to a PDP television or the like because it can perform color conversion processing of a video signal so that the user can comfortably view a 3D video.

DESCRIPTION OF SYMBOLS 1 PDP television 2 Recorder apparatus 3 Antenna 4 SD card 101 Input / output IF part 102 Signal processing part 103 Buffer memory 104 Flash memory 105 PDP
106 Tuner 201 RGB Conversion Unit 202 Inverse Gamma Conversion Unit 203 Mode Acquisition Unit 204 Four Color Conversion Unit 205 Driver

Claims (6)

In addition to the R primary color point, the G primary color point, and the B primary color point, an extended primary color point of a primary color point different from the R primary color point, the G primary color point, and the B primary color point on the (x, y) chromaticity diagram. A self-luminous panel having,
An input unit for inputting video signals;
A signal processing unit that generates an extended color signal expressed using an R primary color point, a G primary color point, a B primary color point, and an extended primary color point based on an input video signal;
Display setting for setting whether the video signal is displayed on the self-luminous panel as a three-dimensional video (hereinafter referred to as a three-dimensional mode) or a two-dimensional video (hereinafter referred to as a two-dimensional mode). And comprising
The signal processing unit generates the extended color signal using a first color conversion method in the three-dimensional mode, and a second color conversion different from the first color conversion method in the two-dimensional mode. A self-luminous display device that generates the extended color signal using a method.   In the first color conversion method, a part of a signal value expressed by the G primary color point is set to the G primary color so that a signal value expressed by the G primary color point among signal values constituting the video signal becomes small. The self-luminous display device according to claim 1, wherein the self-luminous display device is a color conversion method expressed by primary color points different from the dots.   In the first color conversion method, a part of the signal value expressed by the G primary color point is changed to a primary color point different from the G primary color point so that the signal value expressed by the G primary color point becomes a minimum value. The self-luminous display device according to claim 2, which is a color conversion method to express.   When the first color conversion method and the second color conversion method are applied to the same video signal in the signal processing unit, the G primary colors included in the extended color signal generated by the first color conversion method 2. The self-luminous display device according to claim 1, wherein a point signal value is equal to or less than a signal value of a G primary color point included in the extended color signal generated by the second color conversion method.   The self-luminous display device according to claim 1, wherein the display setting unit sets the three-dimensional mode or the two-dimensional mode based on header information of the video signal. The self-luminous display device further includes a receiving unit that receives an operation signal from a user,
The self-luminous display device according to claim 1, wherein the display setting unit performs the three-dimensional mode or the two-dimensional mode based on an operation signal received by the reception unit.

Images