JP4477521B2 - Stereoscopic image display device - Google Patents

Description

  The present invention relates to a stereoscopic image display device, and more particularly to a display image display device for displaying a multi-viewpoint stereoscopic image.

  Conventionally, various methods for displaying a three-dimensional image have been proposed. Among them, a method called “binocular method” that uses binocular parallax is generally used. This is a method of performing stereoscopic vision by preparing a left-eye image and a right-eye image having binocular parallax and independently projecting them on the left and right eyes. As a typical twin-lens system, a field sequential system and a parallax barrier system have been proposed.

  FIG. 13 is a conceptual diagram of the field sequential method. As shown in FIG. 13, in the field sequential method 13, the left eye images 13-1, 13-3,... And the right eye images 13-2, 13-4,. The left-eye image display and the right-eye image display are alternately switched and displayed. The left eye images 13-1, 13-3,... And the right eye images 13-2, 13-4,... Have a vertical resolution that is ½ that of a normal two-dimensional display. The observer wears shutter-type glasses that open and close in synchronization with the display switching cycle. The shutter used here opens the left eye side and closes the right eye side when the left eye image is displayed, and closes the left eye side and opens the right eye side when the right eye image is displayed. In this way, since the left eye image is observed only with the left eye and the right eye image is observed only with the right eye, stereoscopic vision is possible.

  FIG. 14 is a conceptual diagram of the parallax barrier method. FIG. 14A is a diagram illustrating the principle that parallax occurs. On the other hand, FIG. 14B is a diagram showing a screen displayed by the parallax barrier method. As shown in FIG. 14A, an image 204 in which the left eye image and the right eye image shown in FIG. 14B are alternately arranged every other pixel in the horizontal direction is displayed on the image display panel 200. By placing the parallax barrier 201 having slits at an interval narrower than the interval between pixels of the same viewpoint on the front surface of the image display panel 200, the left eye image is observed only by the left eye 202 and the right eye image is observed only by the right eye 203 As a result, stereoscopic viewing becomes possible.

  In the above method, a two-dimensional image can be displayed. For example, in the field sequential method, a two-dimensional image can be displayed by maximizing the aperture ratio of the slit in the parallax barrier method or the method disclosed in Patent Document 1 described below when the observer removes the glasses.

  In Patent Document 1, a slit display LCD for light shielding, an image display LCD, and backlight illumination are arranged in this order, and images from different viewpoints are collected through the slit at a position where the left eye or right eye of the observer is located, respectively. A method of displaying a stereoscopic image by making it illuminate is disclosed.

  In this method, a three-dimensional image of an arbitrary plurality of viewpoints is displayed by changing a slit pattern displayed on the LCD. At this time, a slit is provided between the backlight illumination and the observer, and the area of the light shielding portion of the slit increases in proportion to the number of viewpoints to be displayed. For this reason, when performing display in which a 3D partial image and a 2D partial image are mixed, the brightness of each partial image is not constant, or when switching between 3D image display and 2D image display is performed. There is a problem that the brightness of the screen changes. In order to solve this problem, the backlight illumination is dimmed according to the number of viewpoints at the time of display, the range of brightness of image data can be changed, or the transmittance of the entire slit is adjusted. A method of keeping the brightness constant is disclosed.

JP 9-73049 A

  However, in the technique described in Patent Document 1, since brightness adjustment is performed on the entire image when displaying images from a plurality of viewpoints, the brightness between the viewpoint images included in the image is adjusted. When there is a difference, there is a problem that the difference is emphasized after the brightness adjustment, and it is difficult to view the image as a stereoscopic image, and the observer's eyes become tired.

  Furthermore, in Patent Document 1, when performing stereoscopic display by changing the number of viewpoints, the brightness varies depending on the viewing position, and thus there is a problem that the brightness varies depending on the viewing position. For example, in the case of observing 2-viewpoint data with the left and right eyes in the 2-viewpoint display, and in the case of observing the remaining two viewpoints with the left and right eyes excluding the brightest viewpoint image in the 3-viewpoint display, the brightness is low. There was a problem of being different.

  An object of this invention is to make it easy to see as a stereo image. Another object is to prevent the eyes of the observer from getting tired. Furthermore, it aims at reducing the difference in the brightness by 2 viewpoint display and 3 viewpoints.

  The stereoscopic image display apparatus according to the present invention adjusts the brightness according to at least one of the number of viewpoints in the stereoscopic image data and the number of viewpoints at the time of display, and the brightness of the image at each viewpoint in the stereoscopic image data. A feature is that images of a plurality of viewpoints are displayed by further adjusting the brightness so that the difference between them is reduced.

  That is, according to one aspect of the present invention, there is provided a stereoscopic image display apparatus including a display unit that displays a stereoscopic image based on input image data including image data of a plurality of viewpoints, First correction information for adjusting display brightness according to the first viewpoint number as the score and the second viewpoint number as the viewpoint number included in the input image data is generated. One correction information calculation unit, a second correction information calculation unit that generates second correction information for adjusting brightness for each image data having a different viewpoint in the input image data, and the generated first correction information calculation unit There is provided a stereoscopic image display device comprising a brightness adjustment unit having a correction unit that corrects input image data based on one correction information and the second correction information.

  According to the above apparatus, input image data composed of image data of a plurality of viewpoints can be input, and brightness can be adjusted and displayed according to the number of viewpoints to be displayed. According to this stereoscopic display device, input image data created so as to have appropriate brightness with the number of viewpoints N (N is an integer equal to or greater than 1) is converted into image data with a number of viewpoints other than N and displayed. In this case, the stereoscopic image can be displayed more easily by adjusting the brightness according to the number of viewpoints of the original image data and the number of viewpoints to be displayed.

  According to another aspect of the present invention, there is provided a stereoscopic image display method for displaying a stereoscopic image based on input image data including image data of a plurality of viewpoints, wherein the horizontal viewpoint number N1, the display viewpoint number N2, and the like. , Whether or not N1 and N2 are equal to each other, and N1 and N2 are equal to each other when N1 and N2 are equal to each other. If it is determined, the input image data is directly output as output image data without correction, and if it is determined that N1 is greater than N2, the input image data is based on the difference between N1 and N2. Obtaining at least one correction value to be added to the luminance value of each of the pixels, adjusting the brightness with the correction value, and displaying a stereoscopic image with the adjusted brightness Stereoscopic image display method comprising the door is provided.

  According to the stereoscopic display device of the present invention, input image data created so as to have appropriate brightness with the number of viewpoints N (N is an integer of 1 or more) is converted into image data with the number of viewpoints other than N. When displaying, a stereoscopic image can be displayed more easily by adjusting the brightness according to the number of viewpoints of the original image data and the number of viewpoints to be displayed.

  Further, since different brightness adjustment is performed for each pixel having a plurality of ranges of brightness values, fine brightness adjustment is possible for each local region and according to the brightness value of the pixel.

  Furthermore, according to the stereoscopic display device of the present invention, when adjusting the brightness, the average luminance value of the pixels of the image data for each viewpoint is obtained, and the average luminance value of the pixels of the viewpoint image indicated by the representative image information is calculated. Then, by dividing the average of the luminance values of the pixels of the images of the other viewpoints as weights and reflecting them in the correction value, the brightness of the image data of each viewpoint is adjusted to be equalized. Easy-to-see 3D display is possible.

  In addition, in this case, when the number of viewpoints displayed using the same image data is different because the weight divided by the average luminance value of the pixels of the viewpoint image indicated by the representative image information is reflected in the correction value. Even so, there is an advantage that it is possible to display with constant brightness.

  Hereinafter, a stereoscopic image display device according to an embodiment of the present invention will be described with reference to the drawings. In the following description, 3D is assumed to be three-dimensional or stereoscopic, 2D is assumed to be two-dimensional, a stereoscopic image is assumed to be a 3D image, and a normal two-dimensional image is assumed to be a 2D image.

  FIG. 1 is a functional block diagram showing a configuration example of a stereoscopic image display device according to the first embodiment of the present invention. As shown in FIG. 1, the stereoscopic image display device 1 according to the present embodiment is a device that displays 3D images by inputting 3D image data. The stereoscopic image display apparatus 1 includes a separating unit 2 that separates image data and 3D control information from 3D image data, a 3D control information analyzing unit 3 that analyzes 3D control information, and an image data decoding unit 4 that decodes image data. A display image creating means 5 for creating a display image, a brightness adjusting means 6 for adjusting the brightness, a control means 7 for controlling each part, and a display means 8 for displaying an image.

  Here, the 3D image data is data configured by including image data and 3D control information. Detailed description regarding each means will be described later. First, 3D image data and 3D control information will be described.

  FIG. 2 is a diagram illustrating a configuration example of 3D image data. As shown in FIG. 2, the 3D image data includes a header 11 and image data 12, and 3D control information 11 a is included in the header 11. Examples of the header 11 include an EXIF (Exchangeable Image File Format) header, a header of a file format such as AVI (Audio Video Interleaved), ASF (Advanced Streaming Format), WMV (Windows Media Video), MP4, and the like. Examples of image data include uncompressed image data and compressed image data compressed by a compression method such as JPEG (Joint Photographic Experts Group) or MPEG (Moving Picture Experts Group). The 3D control information 11a includes information regarding the configuration of the image data 12 in the 3D image data and information for controlling display when displaying the 3D image.

  FIG. 3 is a diagram illustrating an example of the 3D control information 11a. As shown in FIG. 3, the 3D control information 11a includes a horizontal and vertical viewpoint number 12a, 12b, an image aspect ratio 12c, and representative image information 12d. Here, the horizontal and vertical viewpoint numbers 12a and 12b indicate information on the number of image data having different viewpoints included in the 3D image data. Further, the image aspect ratio 12c indicates information indicating a value obtained by dividing the vertical scaling factor of the image data 12 by the horizontal scaling factor. The representative image information 12d includes information on which viewpoint image data is selected when performing 2D display.

  4 and 5 are diagrams for explaining an example of image data in the 3D image data. For example, FIG. 4B is an example of image data when the number of horizontal viewpoints is 2, the number of vertical viewpoints is 1, and the image aspect ratio is 1, as shown in FIG. The image data in the 3D image data is obtained by arranging the image data 15a and 15b of the two viewpoints side by side as shown in FIG. 4B (15a and 15b) to form one piece of image data. For example, FIG. 4D shows an example of image data when the number of horizontal viewpoints is 2, the number of vertical viewpoints is 1, and the image aspect ratio is 2, as shown in FIG. The image data in the 3D image data is obtained by arranging the image data of the two viewpoints horizontally reduced by a factor of two as shown in FIG.

  For example, FIG. 5 shows an example of image data in the case where the number of horizontal viewpoints is 4, the number of vertical viewpoints is 2, and the image aspect ratio is 1, up to eight viewpoints 18-1 to 18-8. Are arranged in the order of viewpoint from the upper left to the lower right as numbers 1 to 8 to form one piece of image data. This is the image data in the 3D image data.

  Next, operations of the stereoscopic image display device 1 and each means in the stereoscopic image display device 1 will be described with reference to the drawings. First, 3D image data is input to the stereoscopic image display device 1. The separating unit 2 separates the input 3D image data into a header, 3D control information and image data included in the header, and outputs the separated 3D image data. The input 3D image data is input to the separating unit 2, and is output after being separated into 3D control information, a header, and image data. The 3D control information is input to the 3D control information analysis unit 3, and the header and the image data are input to the image data decoding unit 4.

  The 3D control information analysis unit 3 analyzes the input 3D control information and outputs the analyzed information. Here, the number of viewpoints in the vertical direction is 1. Among the analyzed information, a horizontal viewpoint N1, an image aspect ratio F, and representative image information are output. The horizontal viewpoint number N1, the image aspect ratio F, and the representative image information are input to the display image creating unit 5 and the horizontal viewpoint number N1 is input to the brightness adjusting unit 6, respectively.

  The image data decoding unit 4 is a unit that decodes the input compressed image data if it is image data, and outputs it as it is if it is not image data. Here, the input image data is compressed image data, and the image data decoding unit 4 decodes one piece of image data from the compressed image data and outputs it.

  The control means 7 is means for controlling the number of display viewpoints of the image displayed on the display means 8 and outputting the number of display viewpoints at that time. The control means 7 outputs the display viewpoint number N2. The display image creation means 5 creates and outputs a display image from the input image data, the horizontal viewpoint number N1, the image aspect ratio F, the display viewpoint number N2, and the representative image information. It is. Image data, the horizontal viewpoint number N1, the image aspect ratio F, the display viewpoint number N2, and the representative image information are input to the display image creating means 5. Here, N1 = n and N2 = m (n and m are integers of 1 or more).

  Further, in the following description, when the display image creating means 5 reduces or enlarges image data including image data of a plurality of viewpoints in the horizontal direction, only the image data of the same viewpoint is reduced or enlarged at the same rate for each viewpoint. It shall be.

  6 and 7 are diagrams showing the output image data created by the display image creation means 5 when the number of horizontal viewpoints n> the number of display viewpoints m. 6 is a diagram showing a configuration example of the input image data input to the display image creating means 5. This image 6-1 is composed of image data of n viewpoints from I1 to In. The image data of each viewpoint is represented by Ip (p is an integer of 1 ≦ p ≦ n, and the upper left of the image data (Indicates the number of image data for each viewpoint when raster scanning from the end to the lower right). First, the display image creating means 5 extracts image data for m viewpoints, that is, I1 to Im, from the input image data, as shown in the middle diagram of FIG. At this time, the viewpoint image data to be extracted may be extracted from any position as long as it is continuous viewpoint image data, but is extracted so that the viewpoint image data indicated by the representative image information is included.

  Thereafter, from the extracted image data, as shown in the lower part of FIG. 6, image data enlarged n / m times in the horizontal direction is created. Further, the size of the image data is changed to a size of F / n times in the horizontal direction, and new image data is created.

  FIG. 7 is a diagram for explaining output image data created by rearranging the image data created by the above procedure. FIG. 7A shows image data 7-1 before rearrangement. For each viewpoint, image data before rearrangement is divided into vertical strips in the horizontal direction k (k is an integer of 1 or more). The image data corresponding to each strip is represented by strip data Ijk (j is an integer of 1 ≦ j ≦ m, and indicates the viewpoint number of the viewpoint image arranged from the left end of the image data. It indicates the number of divisions in the direction). The vertical strips thus divided are rearranged to create output image data. FIG. 7B is a diagram showing the image data 7-2 after rearrangement. First, the strip data present on the leftmost side of the image data of each viewpoint is rearranged in the order of I11, I21,..., Ij1. Similarly, all the image data of each viewpoint are rearranged in order up to the rightmost strip data Ijk, and the rearranged image data is output as output image data.

  Next, the case where n <m will be described. FIG. 8 is a diagram showing output image data created by the display image creating means 5 (FIG. 1) when n <m. The upper part of FIG. 8 is a diagram showing the input image data 8-1 inputted to the display image creating means. This image 8-1 is composed of image data of n viewpoints, and the image data of each viewpoint is represented by Ip (p is an integer of 1 ≦ p ≦ n, and the viewpoint images arranged from the left end of the image data. Indicates the viewpoint number.) The display image creation means extracts the image data of continuous viewpoints from the input image data 8-1 for n viewpoints, that is, from I1 to In as it is, and then the remaining (mn) viewpoints created by interpolation. Are added to create image data 8-2 shown in the middle of FIG. Here, the interpolation method may be, for example, a method in which the structure of each object in the image is analyzed from an image of an existing viewpoint and an image viewed from a different viewpoint is created. The interpolation method may be any known method. If interpolation is not possible, a black image may be inserted into the region to be complemented to make a non-display area.

  As shown in the lower part of FIG. 8, the image data reduced in the horizontal direction by n / m times is created for the image data in the middle part of FIG. Further, image data is generated by changing the size of the image data to a size of F / n times in the horizontal direction, and the rearranged image is used as an output image. The rearrangement at this time is the same as the method described in the case of n> m.

  Finally, when n = m, although not shown, the display image creating means outputs an image obtained by rearranging only the input image data as an output image. The rearrangement at this time is the same as the method described in the case of n> m. In addition to outputting as an output image, image position information indicating which viewpoint image among the output images is the viewpoint image indicated by the representative image information is output. The brightness adjustment unit 6 (FIG. 1) is configured to input the number of horizontal viewpoints, the number of display viewpoints of the image displayed on the display unit 8 (FIG. 1), the sum of the brightness of the image data for each number of viewpoints, By adding the correction value to the luminance calculated using the ratio and the luminance of each pixel of the input image data, the image data with the corrected luminance is output.

  FIG. 9 is a functional block diagram showing a configuration example of the brightness adjusting means 6 shown in FIG. As shown in FIG. 9, the brightness adjustment unit 6 receives the horizontal viewpoint number N1, the display viewpoint number N2, the image position information, and the image data, and inputs the reference correction information calculation unit 9-1. , Switch 9-2, correction correction information calculation means 9-3, and correction means 9-4.

  Next, with reference to the drawings and flowcharts, an explanation will be given of the flow of operation when each unit constituting the brightness adjustment unit 6 shown in FIG. 9 corrects the luminance of each pixel of the input image data. To do.

  FIG. 10 is a flowchart showing the operation flow of the brightness adjusting means 6. As shown in FIG. 10, when the process is started, first, in step S1, when the brightness adjusting unit 6 is turned on or reset, the control unit that controls the brightness adjusting unit 6 switches the switch 9-2. By operating, the terminals 10a and 10b are connected, and the process proceeds to step S2. In the determination step S2, the reference correction information calculation unit 9-1 determines whether or not the number of horizontal viewpoints N1 and the number of display viewpoints N2 are input. If it is determined that both are input (YES) ), Go to the determination step S3, otherwise (NO) return to the determination step S2.

  In determination step S3, the reference correction information calculation unit 9-1 determines whether N1 and N2 are equal. If it is determined that they are equal (YES), the process proceeds to step S4, and if not, (NO) step. Proceed to S5. In step S4, the reference correction information calculation unit 9-1 operates the switch 10 so as to connect the terminals 10a and 10c of the switch 9-2. At this time, no correction is performed and the input image data is output as output image data as it is (state a).

  Next, in step S5, the reference correction information calculation unit 9-1 operates the switch 9-2 so as to connect the terminals 10a and 10b of the switch 9-2, and proceeds to determination step S6. In determination step S6, the reference correction information calculation means 9-1 determines whether or not N1 is greater than N2, and if it is determined to be larger (YES), the process proceeds to step S7, otherwise (NO) step S8. Proceed to In step S7, the reference correction information calculation unit 9-1 creates reference correction information (hereinafter referred to as “reference correction information”) from the number of viewpoints N1 and the number of display viewpoints N2, and the correction unit 9-4. And proceed to step S9.

  Here, the correction information is a combination of at least one correction value to be added to the luminance value of each pixel of the input image data and the luminance level (value from 0 to 255) to which the correction value is applied. The correction pattern information represented and the total number of correction patterns included in the correction information are shown. For example, Table 1 shows an example of the correction information calculated in step S7.

  In Table 1, the correction information at this time is assumed that the total number A of correction patterns is 3. In this case, the correction pattern 1 is, for example, “information meaning that −5 (= correction value D1) is subtracted from the luminance values of pixels from 0 to 50 (= luminance level L1)”. Pattern 2 is “information meaning that −10 (= correction value D2) is subtracted from the luminance values of pixels from 51 to 200 (= luminance level L2)”, and correction pattern 3 is “201 To −255 (= correction value D3) for the luminance values of pixels from to 255 (= luminance level L3) ”.

  A method of calculating each correction value Di (i is an integer, 1 ≦ i ≦ A) at this time will be described. The correction value Di can be calculated from Equation 1 below.

  Di = di + {(N2−N1) × αi + N2 × βi} (1)

  Here, di is a basic value of the correction value of the correction pattern i, and α and β are weighting factors. For example, when d1 = 7, N1 = 4, N2 = 2, α1 = 0.5, and β1 = 0.5, D1 is −5. Similarly, when d2 = 12, N1 = 4, N2 = 2, α2 = 0.5, and β2 = 0.5, D2 is −10. Similarly, when d3 = 22, N1 = 4, N2 = 2, α3 = 0.5, and β3 = 0.5, D3 is −20. The above calculation formula of the correction value is an example, and “the difference between the number of viewpoints N1 in the horizontal direction of the original image and the number N2 of display viewpoints actually displayed” and the “number of display viewpoints N2” Other formulas can also be applied as long as different weights are used for the respective formulas.

  Further, the value of the correction value D1 may be a constant, “the difference in the number of viewpoints between the number of viewpoints N1 in the horizontal direction of the original image and the number N2 of display viewpoints actually displayed”, and “the number of display viewpoints”. A table may be prepared in advance so that the two values “N2” are input and the correction value D1 corresponding to these values is output, and the correction value D1 may be determined from this table.

  Table 2 is a table showing another configuration example of the correction information. For example, as shown in Table 2, the total number A of correction patterns may be 2, and the correction values D1 = 0 and D2 = −20 may be set (D2 is d2 = 22, N1 = 4, N2 = 2, α2). = 0.5 and β2 = 0.5 can be obtained from the equation (1)). In this case, it means that correction is not performed for pixels with luminance values of pixels of 200 or less in the input image data.

  Table 3 is a table showing still another configuration example of the correction information. As shown in Table 3, the total number A of correction patterns may be set to 1, and the correction value D1 = −5 (D1 at this time is obtained in the same manner as D1 in Table 1) may be set.

  In the case of Table 3, it means that correction is performed only for pixels whose luminance value of input image data is 50 or less, and that correction is not performed for other pixels. Accordingly, by setting the total number A of correction patterns to 1 as described above or by setting “0” as a correction value, it is possible to correct only a specific portion. The specific part means, for example, that correction is performed only on a bright part (high brightness part) or a dark part (low brightness part) from the beginning in the image data.

  The display means 8 provided in the stereoscopic display device 1 according to the present embodiment is similar to the parallax barrier method described in the conventional example, in that a slit display LCD that displays a slit that blocks light is used as a front surface of an LCD that displays an image ( Or display means for displaying images with different viewpoints. In this case, in order to display images from a plurality of viewpoints, a slit pattern that increases the interval between the openings of the slits may be displayed on the LCD for slit display. This means that the area of the light shielding portion is increased. At this time, the brightness of the displayed image decreases in proportion to the increase in the area of the light shielding portion. Considering this in advance, for example, when 3D image data is created so as to have a brightness suitable for a display device displaying with N1 viewpoints, displaying with N2 viewpoints having a value smaller than N1, There is a problem that the brightness becomes too bright. However, the brightness of the image data to be displayed as described above is adjusted by adding a correction value calculated according to the difference between the number of viewpoints N1 and N2, and adjusting the brightness, so that the three-dimensional image can be displayed with appropriate brightness. An image can be displayed.

  In step S9 in FIG. 10, when the display viewpoint number information N2, image position information, and image data are input to the correction correction information calculation unit 9-3, the correction correction information calculation unit 9-3 inputs the input image. The average brightness Ra (a is an integer. 1 ≦ a ≦ N2) of the image data of each viewpoint is obtained from the data, and the process proceeds to step S10.

  In step S10, the correction correction information calculation unit 9-3 calculates a value qa (a is an integer) obtained by dividing all average values by the average value of the viewpoints indicated by the image position information among the average values of the luminance values of the image data of the respective viewpoints. 1 ≦ a ≦ N2) is created as correction correction information. The correction correction information at this time corresponds to the brightness ratio of the image data of each other viewpoint when the brightness of the image data of the viewpoint indicated by the image position information is 1. At this time, instead of the average of luminance, the sum of luminance values or the maximum value of luminance values may be used. The correction correction information generated in step S10 and the display viewpoint number information N2 are output, and the process proceeds to step S11. Based on the reference correction correction information generated in step S8 and the correction correction information corrected in step 10, the luminance Correct.

  From step S4, the process proceeds to step S12. State a) The input image data is output as it is without luminance correction. From step S11, the process proceeds to step S13, and the state b) the input image data is corrected and output so as to be dark, or the process proceeds to step S14, and the state c) the input image data is corrected and output so as to be bright.

  Below, the process of the correction | amendment means 9-4 in step S11 is demonstrated using a flowchart figure. FIG. 11 is a flowchart showing the flow of operation of the correction means 9-4 in step S11. As shown in FIG. 11, first, in step S12, the display viewpoint number information N2, the image data, the reference correction information, and the correction correction information are input to the correction unit 9-4 (FIG. 9), and step S13. Proceed to In step S13, the luminance value of the pixel to be corrected is selected from the image one pixel at a time from the upper left to the lower right, and the correction information count C is set to 1, and the process proceeds to step S14. Here, the correction information count C is information indicating how many correction values are currently used in the correction pattern in the correction information (C is an integer, 1 ≦ C ≦ A). In step S14, the Cth luminance level in the correction information is assigned to buffer B1 and the correction value is assigned to B2, and the process proceeds to determination step S15. In determination step S15, it is determined whether or not the luminance value of the correction target pixel is equal to or higher than the luminance level B1, and if it is equal to or higher than B1 (YES), the process proceeds to step S16, and if it is lower than B1 (NO), the process proceeds to step S18. . In step S16, the correction information count C is incremented by 1, and the process proceeds to determination step S17. In determination step S17, it is determined whether or not the correction information count C is smaller than the total number A of correction patterns. If it is smaller (YES), the process returns to step S14, and if not (NO), the process proceeds to determination step S20.

  In determination step S20, it is determined whether or not the correction target pixel is the last pixel in the image. If it is the last image (YES), the corrected image is output and the processing of the correction means 9-4 is terminated. Otherwise (NO), the process returns to step S13 to correct the remaining pixels that have not been subjected to the correction process.

  When the process proceeds to step S18, the position of the viewpoint image is obtained from the pixel position from the left end of the correction target pixel in the horizontal direction and the display viewpoint number information N2, and the viewpoint image of the correction target pixel is determined. Ask. Next, a weighting coefficient corresponding to the obtained viewpoint is selected from the correction correction information, and the process proceeds to step S19. In step S19, the correction value B2 is multiplied by the obtained weighting coefficient to create a new correction value. The new correction value is added to the luminance value of the pixel to be corrected, and if the added value is smaller than 0, it is clipped to 0, and if it is larger than 255, it is clipped to 255 and changed to the corrected luminance, and the process proceeds to decision step S20.

  As described above, the correcting unit 9-4 outputs the image data whose brightness is adjusted so that the brightness of the input image data is dark (state b).

  Next, in step S8, the reference reference correction information calculation unit 9-1 creates reference correction information from the viewpoint number N1 and the display viewpoint number N2, outputs the reference correction information to the correction unit 9-4, and proceeds to step S9.

  At this time, an example of the correction information calculated in step S8 is shown in Table 4.

  The calculation formula for calculating each correction value Di at this time is different from the case of step S7 in which the number of viewpoints N1> the number of display viewpoints N2, and the correction value Di is calculated using the following formula (2). To do.

  Di = d'i-{(N2-N1) * [gamma] i-N2 * [eta] i} (2)

  Here, d′ i is a basic value of the correction value of the correction pattern Ii, and γi and ηi are weighting factors. For example, when d′ 1 = 18, N1 = 2, N2 = 3, α1 = 0.5, and β1 = 0.5, D1 is 20. Similarly, when d′ 2 = 8, N1 = 2, N2 = 3, α2 = 0.5, and β2 = 0.5, D2 is 10. Similarly, when d′ 3 = 3, N1 = 2, N2 = 3, α3 = 0.5, and β3 = 0.5, D3 is 5.

  The correction value Di may be a constant as described in D1, or “the number of viewpoints of the horizontal viewpoint number N1 of the original image and the display viewpoint number N2 to be actually displayed. A table is prepared in advance so that two values of “difference” and “number of display viewpoints N2” are input, and a correction value Di corresponding to these values is output, and the correction value Di is determined from this table. May be. Alternatively, the correction value Di may be a constant.

  As described in step S7, when the 3D image data has been created so as to have brightness suitable for the display device that displays the number of viewpoints N1, the display is performed with the number of viewpoints N2 that is larger than N1. Then, the area of the light shielding part of the slit increases, and the brightness of the displayed image becomes dark. However, as described above, it is possible to display with appropriate brightness by adding a correction value to the brightness of the image data to be displayed to increase the brightness.

  Hereinafter, with respect to the operations from step S9 to S11, the overlap already described is avoided. As described above, the correction unit 9-4 creates and outputs corrected image data.

  As described above, the correcting unit 9-4 outputs the image data whose brightness is adjusted so that the brightness of the input image data is brightened (state c).

1) Since the above-described correction value is a correction value created according to the difference between the number of viewpoints N1 and the number of display viewpoints N2 of the 3D image data, a 3D image having various numbers of viewpoints. Even when data is input, it is possible to perform display with appropriate brightness by controlling the brightness more finely according to the input.

2) In addition, as the number of viewpoints N2 to be actually displayed increases, the area of the light shielding portion of the slit increases, and as a result, the display becomes dark. Therefore, by changing the correction value according to the size of N2. It is possible to adjust the brightness according to the characteristics of the display means 8.

3) In addition, when adjusting the brightness, the average of the luminance values of the pixels of the image data for each viewpoint is obtained, and the average of the luminance values of the pixels of the viewpoint image indicated by the representative image information is calculated. The brightness of the image data of each viewpoint is adjusted to be equal by reflecting the correction value as a weighted value obtained by dividing the average of the luminance values of the pixels. Accordingly, it is possible to make a stereoscopic display easier to see. In this case, if the average value of the luminance values of the pixels of the viewpoint image indicated by the representative image information is reflected in the correction value as a weight, the number of viewpoints displayed using the same image data may be different. However, it is possible to display with a certain brightness.

  In addition, by adjusting different brightness for each pixel having a brightness value in a plurality of ranges, it is possible to finely adjust the brightness for each local area according to the brightness value of the pixel. is there.

  The image data whose brightness has been adjusted as described above is input to the display means 8. The display unit 8 is a unit that displays the input image data in 2D or 3D, and is a unit that can control the number of display viewpoints of the image displayed by the control unit 7 during 3D display.

  FIG. 12 is a conceptual diagram for explaining the operation of the display means 8.

  FIG. 12A is a top view of the display unit 8 when the number of display viewpoints N2 = 2 is viewed from the top of the apparatus. For example, the display means 8 includes a backlight 100, an image display LCD 101, and a slit display LCD 102. In this case, the control means 7 controls the slit display LCD 102 to form a slit pattern on the LCD 102 for slit display in which the slit aperture ratio and the period of the opening portion S1 are set for two viewpoints. Thus, two viewpoint images can be displayed.

  FIG. 12B is a view of the display unit 8 when the number of display viewpoints N2 = 3, as viewed from the top of the apparatus. As in the case of the two viewpoints, the control means 7 controls the LCD 102 for slit display, and the slit pattern in which the slit aperture ratio and the period of the opening portion S2 are set for the three viewpoints is displayed. By forming it above, it is possible to display images from three viewpoints. In this way, the display means 8 can display the input image data by changing the number of viewpoints to be displayed in accordance with the display viewpoint number N2 by changing the slit pattern. .

  In the correction unit 9-4, the input image data is corrected by adding the correction value finally created by the correction unit 9-4 to the luminance of the pixel of the input image data. Correction may be performed by multiplying the luminance of the input image data as a weighting value for the luminance.

  For example, Table 5 shows another configuration example of the correction information calculated in step S7.

  In Table 5, the correction information at this time is that the total number A of correction patterns is 3, and the correction pattern 1 is that the luminance values of pixels from 0 to 50 (= luminance level L1) are 95 (= correction value D1)%. Information that means brightness, that is, multiplying by 0.95 ”, correction pattern 2 has a luminance value of pixels from 51 to 255 (= luminance level L2) of 90 (= correction value D2)% Information that means brightness, that is, multiplication by 0.9 ”.

  An example of a method for calculating each correction value Di (i is an integer, 1 ≦ Ii ≦ A) at this time will be described below. The correction value Di is calculated from the equation (3).

  Di = 100−di + {(N2−N1) × αi + N2 × βi} (3)

Here, d1 is a basic value of the correction value of the correction pattern Ii, and α and β are weighting factors.
For example, when d1 = 7, N1 = 4, N2 = 2, α1 = 0.5, and β1 = 0.5, D1 is 95. Similarly, when d2 = 12, N1 = 4, N2 = 2, α2 = 0.5, and β2 = 0.5, D2 is 90.

  In this way, correction may be performed by multiplying the obtained correction value by the luminance value of the pixel in the input image data together with the correction correction information in step S11.

  Further, when correction is performed by the correction unit 9-4, edges may be extracted from the image data for each viewpoint. At this time, the extraction method may be any of the conventional methods, for example, a method using a secondary differentiation process, a Hough transform, a tension method, a contraction method, an extended trace method, or the like. After extracting the edge in this way, correction may not be performed for the pixel at the location determined as the edge and the surrounding pixels. In this case, 4 neighboring pixels or 8 neighboring pixels of the pixel determined to be an edge can be given as examples of the peripheral pixels. By doing so, it is possible to adjust the brightness while preventing the occurrence of blurring of the display at the edge without adjusting the brightness for the edge portion.

  Further, when the luminance is corrected by the correcting unit 9-4, a parallax may be obtained for each specific area from image data of adjacent viewpoints, and the luminance value may be further corrected based on the parallax value. For example, disparity extraction means is installed in front of the correction means 9-4, image data of adjacent viewpoints is extracted from the input image data, disparity is obtained for each specific area by image matching or the like, and the disparity obtained for each area May be input to the correction means 9-4. In this case, when the parallax of the specific area indicates that the stereoscopically displayed image appears to protrude beyond the display surface, the correction value is increased so that the brightness of the area becomes stronger. You may do it. On the contrary, in a region where the image can be retracted, the correction may be performed with a smaller correction value so that the brightness is further weakened.

  Further, only when the area is visible and the correction value is a positive value, the correction value may be increased and the correction may be performed so that the brightness of the area is further increased. Only when the correction value is negative and the correction value is a negative value, correction may be performed with a smaller correction value so that the brightness of the region is further weakened.

  Also, if the correction value is negative or the correction value is negative, or if the correction value is positive and the correction value is positive, do not perform correction. May be. In general, a stereoscopic image has a stronger feeling of popping out as the image popping out toward the front is brighter, and conversely, a feeling of depth becomes stronger as an image retracted into the back is darker. Therefore, as described above, by taking the parallax into consideration when adjusting the brightness, it is possible to coordinate the stereoscopic effect by adjusting the brightness, and to prevent the stereoscopic effect from being weakened. There is an advantage that you can.

  As described above, according to the stereoscopic display device according to the present embodiment, input image data created so as to have appropriate brightness with the number of viewpoints N (N is an integer of 1 or more) When the image data is converted into image data with the number of viewpoints and displayed, the stereoscopic image can be displayed more easily by adjusting the brightness according to the number of viewpoints of the original image data and the number of viewpoints to be displayed.

  In addition, since the brightness that differs for each pixel having luminance values in a plurality of ranges is adjusted, it is possible to finely adjust the brightness for each local region and according to the luminance value of the pixel.

  Further, according to the stereoscopic display device according to the present embodiment, when adjusting the brightness, the average of the luminance values of the pixels of the image data for each viewpoint is obtained, and the average of the luminance values of the pixels of the images of the other viewpoints is obtained. Since the brightness divided by the average of the luminance values of the pixels of the viewpoint image indicated by the representative image information is weighted and reflected in the correction value, the brightness of the image data of each viewpoint is adjusted to be uniform. A stereoscopic display that is easier to see is possible.

  Furthermore, in this case, since the weight divided by the average of the luminance values of the pixels of the viewpoint image indicated by the representative image information is reflected in the correction value as a weight, the number of viewpoints displayed using the same image data is different. Even if it exists, there exists an advantage that it can display with fixed brightness.

  The present invention is applicable to a stereoscopic image display device.

It is a functional block diagram which shows the structural example of the stereo image display apparatus by one embodiment of this invention. It is a figure which shows the example of 1 structure of 3D image data. It is a figure which shows the example of 1 structure of 3D control information. It is a figure which shows one structural example of the image data in 3D image data. It is a figure which shows one structural example of the image data in 3D image data. It is a figure for demonstrating the output image data which a display image preparation means produces. It is a figure for demonstrating the output image data which a display image preparation means produces. It is a figure for demonstrating the output image data which a display image preparation means produces. It is a functional block diagram which shows the structural example of a brightness adjustment means. It is a flowchart figure which shows the flow of operation | movement of a brightness adjustment means. It is a flowchart figure which shows the flow of operation | movement of a correction | amendment means. 12A and 12B are conceptual diagrams for explaining the operation of the display means. It is a conceptual diagram for demonstrating a field sequential system. It is a conceptual diagram for demonstrating a parallax barrier system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stereoscopic image display apparatus 2 Separation means 3 3D control information analysis means 4 Image data decoding means 5 Display image creation means 6 Brightness adjustment means 7 Control means 8 Display means 9-1 Reference correction information calculation means 9-2 Switch 9-3 Correction correction information calculation means 9-4 Correction means 100 Backlight 101 Image display LCD
102 LCD for slit display
200 image display panel 201 parallax barrier 202 right eye 203 left eye

Claims (10)

A stereoscopic image display device comprising display means for displaying a stereoscopic image based on input image data including image data of a plurality of viewpoints,
A first number for adjusting display brightness according to a first number of viewpoints that is the number of viewpoints displayed on the display means and a second number of viewpoints that is the number of viewpoints included in the input image data. First correction information calculation means for generating the correction information of the second, and second correction information calculation means for generating the second correction information for adjusting the brightness for each image data having a different viewpoint in the input image data And a brightness adjusting means for correcting the input image data based on the created first correction information and the second correction information.   2. The stereoscopic image display according to claim 1, wherein the brightness adjustment unit is a unit that adjusts the brightness of the display by correcting a luminance value of a pixel included in the input image data. apparatus.   The brightness adjusting unit adjusts the brightness according to at least one of the first viewpoint number and the second viewpoint number, and further, brightness of an image at each viewpoint in the stereoscopic image data. The stereoscopic image display apparatus according to claim 1, wherein the brightness is adjusted in a direction in which the difference in height is reduced.   4. The brightness adjustment unit is a unit that classifies the luminance values into a plurality of different levels and performs different corrections on the luminance values classified into the different levels, respectively. The three-dimensional image display apparatus described in 1.   5. The stereoscopic image display apparatus according to claim 4, wherein the number of the plurality of levels is 2, and at least one level is corrected.   The second correction information calculation means obtains an average of luminance for each image data of different viewpoints, obtains a ratio with the average of the luminance of image data of a reference viewpoint, and sets the luminance value so that the ratio is constant The stereoscopic image display apparatus according to claim 1, further comprising means for generating second correction information for correcting the image.   The second correction information calculation means includes means for obtaining the image data of the reference viewpoint from representative image information indicating which viewpoint is included in the input image data and which is the reference viewpoint. The stereoscopic image display device according to claim 6.   8. The three-dimensional image according to claim 7, wherein a value obtained by dividing the luminance value of each pixel by the average of the luminance values of the pixels of the viewpoint image indicated by the representative image information is reflected in the correction value as a weighting value for the pixel. Image display device. A stereoscopic image display method for displaying a stereoscopic image based on input image data including image data of a plurality of viewpoints,
Determining whether the horizontal viewpoint number N1 and the display viewpoint number N2 have been input;
Determining whether N1 and N2 are equal when it is determined that both have been input; and
If it is determined that N1 and N2 are equal, the input image data is output as it is as output image data without correction, and if it is determined that N1 is greater than N2, N1 and N2 Obtaining at least one correction value to be added to the luminance value of each pixel of the input image data based on the difference; and
And a step of adjusting the brightness with the correction value and displaying a stereoscopic image with the adjusted brightness. A program for causing a computer to execute the method according to claim 9 .

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