Image processing device, image display device, image processing method, image processing program and recording medium in which image processing program is recorded

Abstract

To provide an image processing device and the like that can display a whole of an image which includes a near view display area and a distant view display area without sense of discomfort.SOLUTION: An image processing device comprises: a depth information acquisition unit that acquires image depth information of each of a plurality of display areas which constitute an image based on an image signal; and an area-by-area gradation value adjustment unit that performs individual gradation value adjustment for each of the plurality of display areas depending on image depth identified by the image depth information of each of the plurality of display areas.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to an image processing device, an image display device, an image processing method, an image processing program, and a recording medium on which the program is recorded. [Background technology]

[0002] In recent years, as disclosed in Patent Document 1, image display devices including image processing devices have been developed. In such image processing devices, sharpness processing is performed. As a result, enhancement processing and blurring processing are performed on images that give a sense of depth. As a result, the sense of depth of the image is enhanced. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-177469 Summary of the Invention [Problem to be solved by the invention]

[0004] For example, there are images in which the depth distances of the multiple display areas are random, such as a photograph of a tree with multiple leaves, or images in which the depth direction cannot be determined. In the case of such images, it is difficult to give the image a sense of depth using the enhancement and blurring processes disclosed in Patent Document 1.

[0005] Specifically, according to the above technology, the sense of depth of the image is expressed by changing the manner of sharpness processing in accordance with the sense of depth based on image depth information. Therefore, the sharpness differs for each of the multiple display areas of the image. In other words, the sharpness processing is weakened (blurring processing) in the distant view display area of ​​the image, while the sharpness is strengthened in the foreground view display area of ​​the image. Therefore, in the foreground view display area where sharpness is strengthened, edges are overemphasized. This may cause a sense of discomfort to the viewer in the foreground view display area.

[0006] Furthermore, the large difference in edges between display areas with emphasized edges and display areas with weakened edges may cause an unnatural feeling in the overall image. Furthermore, edges are emphasized in foreground display areas to create a sense of detail. This may result in flashing noise in high-frequency components during video playback, creating an unnatural feeling in the image.

[0007] The present disclosure has been made in consideration of the above-mentioned problems. An object of the present disclosure is to provide an image processing device and an image display device that can display an entire image including a foreground display area and a background display area without creating a sense of incongruity. Another object of the present disclosure is to provide an image processing method, an image processing program, and a recording medium having the program recorded thereon that can display an entire image including a foreground display area and a background display area without creating a sense of incongruity. [Means for solving the problem]

[0008] An image processing device according to one embodiment of the present disclosure includes a depth information acquisition unit that acquires image depth information for each of a plurality of display areas that constitute an image based on an image signal, and an area-specific gradation value adjustment unit that performs individual gradation value adjustment for each of the plurality of display areas in accordance with the image depth specified by the image depth information for each of the plurality of display areas.

[0009] An image display device according to an aspect of the present disclosure includes the image processing device described above, and a display panel that displays an image based on an image signal transmitted from the image processing device.

[0010] An image processing method according to one aspect of the present disclosure includes the steps of acquiring image depth information for each of a plurality of display areas that constitute an image based on an image signal, and performing individual gradation value adjustment for each of the plurality of display areas according to the image depth of each of the plurality of display areas identified by the image depth information.

[0011] An image processing program according to one embodiment of the present disclosure is an image processing program for causing a computer to operate as a depth information acquisition unit that acquires image depth information for each of a plurality of display areas that constitute an image displayed based on an image signal, and an area-specific gradation value adjustment unit that performs individual gradation value adjustment for each of the plurality of display areas in accordance with the image depth of each of the plurality of display areas identified by the image depth information.

[0012] A recording medium according to one aspect of the present disclosure is a computer-readable recording medium on which the image processing program described above is recorded. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a functional block diagram of an image display device including an image processing device according to an embodiment; [Figure 2] 2 is a diagram for explaining a plurality of display areas that constitute an image displayed on a display panel of the image processing device according to the present embodiment. FIG. [Figure 3] 10 is a flowchart illustrating a process executed by the image processing apparatus according to the embodiment. [Figure 4] FIG. 2 is a diagram showing a first example of an image specified by an image signal input to the image processing device according to the embodiment. [Figure 5] FIG. 2 is a diagram showing a first example of image depth information acquired from an image signal input to the image processing device according to the embodiment. [Figure 6] FIG. 10 is a diagram showing a second example of an image specified by an image signal input to the image processing device according to the embodiment. [Figure 7] FIG. 10 is a diagram showing a second example of image depth information acquired from an image signal input to the image processing device according to the embodiment. [Figure 8] 10 is a diagram showing a gamma curve (when the average luminance is high) during image processing according to the APL (average luminance) of the entire screen, which is executed by the image processing unit of the image processing apparatus according to the embodiment. FIG. [Figure 9] 10 is a diagram showing a gamma curve used by an area gradation value adjustment unit of the image processing apparatus according to the embodiment to adjust gradation values ​​of a distant view display area. [Figure 10] 10 is a diagram showing a gamma curve used by an area gradation value adjustment unit of the image processing apparatus according to the embodiment to adjust the gradation values ​​of a display area of ​​a foreground. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, an image processing device, an image display device, an image processing method, an image processing program, and a recording medium on which the program is recorded according to embodiments of the present disclosure will be described with reference to the drawings. Note that in the drawings, the same or equivalent elements are designated by the same reference numerals, and redundant descriptions will not be repeated.

[0015] (Embodiment 1) An image processing device, an image display device, an image processing method, an image processing program, and a recording medium on which the program is recorded according to the first embodiment will be described with reference to FIGS.

[0016] Fig. 1 is a functional block diagram of an image display device 100 including an image processing device 10 according to the present embodiment. Fig. 2 is a diagram illustrating a plurality of display areas DA constituting an image DI displayed on a display panel 50 of the image processing device 10 according to the present embodiment.

[0017] 1 and 2, the image display device 100 includes a display panel 50 and an image processing device 10 that controls an image displayed on the display panel 50. The image display device 100 may be a device other than a television receiver, such as a smartphone or a personal computer.

[0018] The display panel 50 displays an image DI. The image D1 is controlled individually for each of a plurality of display areas DA arranged in a matrix. However, the arrangement of the plurality of display areas DA may be any arrangement other than a matrix arrangement. The display panel 50 may be any type of display panel, such as a liquid crystal display panel, an OLED (Organic Light Emitting Diode) display panel, or a QLED (Quantum Dot Light Emitting Diode) display panel.

[0019] The image processing device 10 includes an image data acquisition unit 1, an image data analysis unit 2, a depth information acquisition unit 3, a signal processing unit 4, a per-area gradation value adjustment unit 5, and a panel display unit 6. The image processing device 10 also includes a memory serving as a computer-readable recording medium. The image processing device 10 also includes a processor that causes the image data acquisition unit 1, the image data analysis unit 2, the depth information acquisition unit 3, the signal processing unit 4, the per-area gradation value adjustment unit 5, and the panel display unit 6 to perform predetermined operations based on an image processing program stored in the memory. The image processing device 10 is also referred to as a controller. However, at least one of the image data acquisition unit 1, the image data analysis unit 2, the depth information acquisition unit 3, the signal processing unit 4, the per-area gradation value adjustment unit 5, and the panel display unit 6 may be configured using a dedicated electronic circuit.

[0020] The image data acquisition unit 1 is a tuner that receives an image signal from an external device. However, the image data acquisition unit 1 may be an antenna that receives the image signal as a radio wave from an external device, or a connector electrically connected to electrical wiring that transmits the image signal from an external device. The image data analysis unit 2 receives the image signal via the tuner, analyzes the image signal to extract various pieces of information, and transmits the extracted information together with the image signal to the depth information acquisition unit 3 and the signal processing unit 4, respectively.

[0021] The image processing device 10 may include a camera (not shown). In this case, the image signal may be an image signal of an image DI captured by the camera. The image processing device 10 may also include a non-volatile memory. In this case, the image signal may be an image signal of an image DI stored in the non-volatile memory (not shown). The image processing device 10 may also include a USB (Universal Serial Bus) interface (not shown). In this case, the image signal may be an image signal of an image DI acquired from an external memory (not shown) connected to the USB interface. The image DI may also be either a moving image (video) or a still image.

[0022] The depth information acquisition unit 3 acquires image depth information for each of a plurality of display areas DA constituting an image based on an image signal. The depth information acquisition unit 3 acquires image depth information for a currently acquired image signal using a learning result of image depth information for a plurality of image signals previously acquired. The plurality of areas DA may correspond to a plurality of pixels in a one-to-one relationship. In other words, the depth information acquisition unit 3 may include a unit that acquires image depth for each of a plurality of pixels. However, the depth information acquisition unit 3 of this embodiment acquires image depth for each display area DA, that is, for each of a plurality of pixels, with a plurality of pixels constituting one display area DA.

[0023] Specifically, the depth information acquisition unit 3 acquires image depth information of the image signals received from the image data analysis unit 2 based on the learning results of multiple image signals corresponding to multiple images by AI (Artificial Intelligence). Any method may be used to acquire image depth information by AI learning. This allows the accuracy of the image depth information acquired by the depth information acquisition unit 3 to be improved by learning. However, the image depth information may be acquired by any method other than the AI ​​learning method.

[0024] The signal processing unit 4 forms an image based on the image signal. The signal processing unit 4 performs normal image processing, such as sharpness processing, gamma correction processing, or contrast processing, on the entire image DI including the multiple display areas DA.

[0025] The area-specific gradation value adjustment unit 5 performs individual gradation value adjustment for each of the multiple display areas DA in accordance with the image depth specified by the image depth information for each of the multiple display areas DA. The individual gradation value adjustment for each of the multiple display areas DA is performed in addition to the gradation value adjustment for the entire image DI including the multiple display areas DA. This allows optimal contrast control to be performed according to the image DI displayed on the display panel DP. This makes it possible to perform optimal gradation value adjustment for the image signal of each of the multiple display areas DA. This makes it possible to display the entire image DI including the distant display area DA and the near display area DA without creating a sense of incongruity, compared to when sharpness processing and blur processing are performed.

[0026] In adjusting the individual gradation values, the area-specific gradation value adjuster 5 increases the contrast of the foreground display area DA, which has a relatively small image depth, among the multiple display areas DA, compared to the contrast of the background display area DA, which has a relatively large image depth. As a result, the image in the foreground display area DA is displayed more clearly, while the image DI in the background display area DA is displayed less clearly (blurred). In other words, in the image DI in the foreground display area DA, the color boundaries and contours are made clear, while in the image DI in the background display area DA, the color boundaries and contours are made unclear (fuzzy). As a result, the image DI can be displayed with a good sense of perspective.

[0027] That is, the depth information acquisition unit 3 uses the distribution of image depth of the image DI acquired from the image signal to enable the display area DA of the distant view to be distinguished from the display area DA of the foreground view. For example, the display area DA including a forest that is the background of a person is considered to be the display area DA of the distant view, and therefore its contrast is relatively reduced. As a result, the color boundaries and contours of the distant view, such as the forest, included in the image DI are displayed vaguely. Therefore, a sense of depth can be imparted to the entire image DI displayed based on the image signal. On the other hand, the display area DA including a person, for example, is considered to be the display area DA of the foreground view, and therefore its contrast is relatively increased. As a result, the color boundaries and contours of the foreground view, such as the person, included in the image DI are displayed clearly.

[0028] The panel display unit 6 displays an image on the display panel 50 based on an image signal in which the overall gradation value of the multiple display areas DA has been adjusted by the signal processing unit 4 and the gradation value of each of the multiple display areas has been individually adjusted by the area-specific gradation value adjustment unit 5.

[0029] FIG. 3 is a flowchart for explaining the processing executed by the image processing device 10 of this embodiment.

[0030] In step S1, the image data acquisition unit 1 receives an image signal from the outside. In step S2, the image data analysis unit 2 receives the image signal via the image data acquisition unit 1 and transmits the image signal together with various information obtained by analyzing the image signal to the depth information acquisition unit 3 and the signal processing unit 4, respectively.

[0031] In step S3, the depth information acquisition unit 3 acquires image depth information for each of the plurality of display areas DA constituting the image DI displayed based on the image signal, using the image signal received from the image data analysis unit 2. In step S4, the signal processing unit 4 uses the image signal received from the image data analysis unit 2 to perform sharpness processing, gamma correction processing, contrast processing, or the like on all of the image DI including the plurality of display areas DA.

[0032] In step S5, the per-area gradation value adjuster 5 performs individual image gradation value adjustment. Specifically, the per-area gradation value adjuster 5 increases the contrast of the foreground display area DA, which has a relatively small image depth, among the multiple display areas DA, compared to the contrast of the background display area DA, which has a relatively large image depth. The panel display unit 6 displays an image on the display panel 50 using an image signal in which the overall gradation value of the multiple display areas DA has been adjusted by the signal processor 4 and the gradation value of each of the multiple display areas DA has been individually adjusted by the per-area gradation value adjuster 5.

[0033] Fig. 4 is a diagram showing a first example of an image specified by an image signal input to the image processing device 10 of this embodiment. Fig. 5 is a diagram showing a first example of image depth information acquired from an image signal input to the image processing device 10 of this embodiment. The numerical values ​​shown in Fig. 5 are image depth information for the display area DA portion.

[0034] In the case of an image DI as shown in FIG. 4, the multiple display areas DA are divided as shown in FIG.

[0035] Fig. 6 is a diagram showing a second example of an image specified by an image signal input to the image processing device 10 of this embodiment. Fig. 7 is a diagram showing a second example of image depth information acquired from an image signal input to the image processing device 10 of this embodiment. The numerical values ​​shown in Fig. 7 are image depth information for the display area DA portion.

[0036] In the case of an image DI as shown in FIG. 6, the multiple display areas DA are divided as shown in FIG.

[0037] For example, when a viewer is viewing an image such as that shown in FIG. 4 or FIG. 6, the area-by-area gradation value adjuster 5 executes the following control.

[0038] The area-specific gradation value adjustment unit 5 analyzes the image signal based on the image depth information acquired by the depth information acquisition unit 3. As a result, the area-specific gradation value adjustment unit 5 considers the display area DA in which the ocean is displayed in FIG. 5 to be the foreground, and the display area DA in which the person is displayed in FIG. 7 to be the foreground. In this case, the area-specific gradation value adjustment unit 5 executes a process to increase the contrast of the display area DA determined to be the foreground. As a result, the ocean is displayed clearly in FIG. 4, and the person is displayed clearly in FIG. 6. Conversely, the area-specific gradation value adjustment unit 5 considers the display area DA in which the sky is displayed to be the background of the person in FIG. 5 to be the background, and the display area DA in which the forest, which is the background of the person, is displayed to be the background. In this case, the area-specific gradation value adjustment unit 5 executes a process to reduce the contrast of the display area DA determined to be the background. As a result, the sky, which is considered to be the background, is displayed blurred in FIG. 4, and the background of the person, which is considered to be the background, is displayed blurred in FIG. 6. As a result, both the image of the distant view area and the image of the near view area can be displayed without creating a sense of incongruity, and the perspective of the image can be expressed satisfactorily.

[0039] (Embodiment 2) An image processing device, an image display device, an image processing method, an image processing program, and a recording medium on which the program is recorded according to the second embodiment will be described with reference to Figures 8 to 10. Note that the following description of the same aspects as those of the image processing device, image display device, image processing method, image processing program, and recording medium on which the program is recorded according to the first embodiment will not be repeated. The following image processing device, image display device, image processing method, image processing program, and recording medium on which the program is recorded differ from the above-described image processing device, image display device, image processing method, image processing program, and recording medium on which the program is recorded in the following respects.

[0040] In the image processing device 10 of this embodiment, the per-area gradation value adjustment unit 5 performs gamma control corresponding to the image depth information for each of the plurality of display areas DA stored therein, based on the image depth information acquired by the depth information acquisition unit 3. This allows optimal gamma control to be performed according to the image displayed on the display panel DP.

[0041] Fig. 8 is a diagram showing a gamma curve (when the average brightness is high) during image processing according to the APL (average brightness) of the entire screen, which is executed by the image processing unit 4 of the image processing device 10 of this embodiment. Fig. 9 is a diagram showing a gamma curve used by the area gradation value adjustment unit 5 of the image processing device 10 of this embodiment for adjusting the gradation values ​​of the distant display area DA. Fig. 10 is a diagram showing a gamma curve used by the area gradation value adjustment unit 5 of the image processing device 10 of this embodiment for adjusting the gradation values ​​of the foreground display area DA.

[0042] In this embodiment, the image processing device 10 corrects the gradation values ​​of the image signal corresponding to the entire image DI including multiple display areas DA using the gamma curve shown in Fig. 8. Then, the image processing device 10 corrects the gradation values ​​of the image signal corresponding to each of the multiple display areas DA using the gamma curve shown in Fig. 9 or the gamma curve shown in Fig. 10.

[0043] In the individual gradation value adjustment, the per-area gradation value adjustment unit 5 corrects the gradation value of the image signal using a first gamma curve that generates a relatively large contrast in a first display area among the multiple display areas DA, which has a relatively small image depth. On the other hand, in the individual gradation value adjustment, the per-area gradation value adjustment unit 5 does not correct the gradation value of the image signal in a display area DA among the multiple display areas DA, which has a relatively large image depth. Furthermore, in the individual gradation value adjustment, the per-area gradation value adjustment unit 5 may correct the gradation value of the image signal using a second gamma curve γ2 that generates a relatively small contrast in a display area DA among the multiple display areas DA, which has a relatively large image depth. The image processing device 10 of this embodiment can also display an image DI in which the foreground display area DA and the background display area DA have a good sense of perspective. [Explanation of symbols]

[0044] 1 Image data acquisition unit 2 Image data analysis section 3 Depth information acquisition section 4. Signal Processing Section 5 Area-by-area tone value adjustment section 6 Panel display 10 Image processing device 50 Display Panel 100 Image display device DA display area DI Image

Claims

1. a depth information acquisition unit that acquires image depth information for each of a plurality of display areas that form an image based on an image signal; and an area-by-area gradation value adjustment unit that performs individual gradation value adjustment for each of the plurality of display areas in accordance with an image depth specified by the image depth information for each of the plurality of display areas. Image processing device.

2. In the individual gradation value adjustment, the area gradation value adjustment unit increases the contrast of a first display area having a relatively small image depth among the plurality of display areas compared to the contrast of a second display area having a relatively large image depth. The image processing device according to claim 1 .

3. In the individual gradation value adjustment, the area gradation value adjustment unit Among the plurality of display areas, in a first display area in which the image depth is relatively small, a first gamma curve that produces a relatively large contrast is used to correct the gradation value of the image signal, while In a second display area among the plurality of display areas, in which the image depth is relatively large, the gradation value of the image signal is not corrected, or the gradation value of the image signal is corrected using a second gamma curve that generates a relatively small contrast. The image processing device according to claim 1 .

4. The depth information acquisition unit acquires the image depth information of the image signal acquired this time by using a learning result of the image depth information of the image signal acquired previously. The image processing device according to claim 1 .

5. an image processing device according to any one of claims 1 to 4; a display panel that displays an image based on the image signal transmitted from the image processing device, Image display device.

6. The method includes a step of acquiring image depth information for each of a plurality of display areas constituting an image based on an image signal, and a step of performing individual gradation value adjustment for each of the plurality of display areas in accordance with the image depth of each of the plurality of display areas specified by the image depth information. Image processing methods.

7. Computer, a depth information acquisition unit that acquires image depth information for each of a plurality of display areas that form an image based on an image signal; and an area-by-area gradation value adjustment unit that performs individual gradation value adjustment for each of the plurality of display areas in accordance with the image depth of each of the plurality of display areas specified by the image depth information; Image processing program to operate as.

8. A computer-readable recording medium on which the image processing program according to claim 7 is recorded.

Images