CN104811679A - Stereoscopic image adjustment method and image processing device - Google Patents

Abstract

The invention provides a method for adjusting a stereo image and an image processing device. The stereoscopic image is displayed on a screen. The adjusting method comprises the following steps: obtaining a plurality of depth values of the stereoscopic image, wherein a plurality of first depth values correspond to the edge area of the screen; judging whether one of the first depth values is a negative parallax; and if one of the first depth values is negative parallax, adjusting the depth values to ensure that the first depth values are not negative parallax. Therefore, the violation of the three-dimensional window can be avoided.

Description

Stereoscopic image adjustment method and image processing device

technical field

The invention relates to an adjustment method, and in particular to an adjustment method of a stereoscopic image and an image processing device using the method.

Background technique

Stereo images are composed of two or more images from different perspectives. A stereoscopic image display allows the left eye to see an image from one perspective and the right eye to see an image from another perspective, whereby the brain synthesizes a three-dimensional image. However, images from different perspectives are displayed on a flat screen, so the human eye is focused on the screen, and the brain synthesizes a three-dimensional image that is in front of or behind the screen. Such a situation may cause discomfort or dizziness to the viewer. When an object in a stereo image is displayed at the edge of the screen, part of the object may be "occluded" by the edge of the screen. When the human eye sees the part covered by the edge of the screen, it will intuitively think that the part covered is imaged behind the screen. However, if the portion not covered by the screen is imaged in front of the screen, the user will feel uncomfortable. This situation is called stereoscopic window violation.

Referring to FIG. 1 , if the left eye 110 sees the image 120 and the right eye sees the image 122 , the user feels that the object 130 is imaged in front of the screen 140 . However, object 150 is obscured by screen 140 . It will be difficult for the user to synthesize the covered object 150 and feel uncomfortable.

Therefore, how to avoid stereoscopic window violation is an issue that those skilled in the art are concerned about.

Contents of the invention

Embodiments of the present invention provide a stereoscopic image adjustment method and an image processing device using the adjustment method, which can avoid stereoscopic window violation.

An embodiment of the present invention provides a method for adjusting a stereoscopic image, which is used in an image processing device. The stereoscopic image is displayed on a screen. The adjustment method includes: obtaining multiple depth of field values of the stereoscopic image, wherein the multiple first depth of field values correspond to the edge regions of the above-mentioned screen; judging whether one of the first depth of field values is negative parallax; and if the first depth of field values One of them is negative parallax, and the above-mentioned depth of field value is adjusted so that the first depth of field value is not negative parallax.

In an embodiment, the above stereoscopic image includes a first image and a second image. The step of obtaining the depth of field value of the stereoscopic image includes: obtaining a plurality of first feature points of the first image, and obtaining a plurality of second feature points of the second image; and pairing the first feature points and the second feature points to calculate Depth of field value above.

In an embodiment, the step of determining whether one of the first depth values is negative parallax includes: obtaining a minimum depth value among the first depth values; and determining whether the minimum depth value is negative parallax.

In an embodiment, the step of adjusting the depth of field value so that the first depth of field value does not have negative parallax includes: adding an offset value to the minimum depth of field value to generate a second depth of field value, wherein the second depth of field value is not negative parallax; And add the offset value to the depth of field value other than the minimum depth of field value.

In an embodiment, the above-mentioned second depth of field value is zero parallax.

From another perspective, an embodiment of the present invention provides an image processing device including a memory and a processor. The memory stores a plurality of instructions. The processor is used to execute these instructions to perform multiple steps: obtain multiple depth values of the stereoscopic image, wherein the multiple first depth values correspond to edge regions of a screen; determine whether one of the first depth values is a negative parallax ; and if one of the first depth of field values is a negative parallax, adjust the above depth of field value so that the first depth of field value is not a negative parallax.

Based on the above, the adjustment method and the image processing device proposed by the embodiments of the present invention can avoid stereoscopic window violation by adjusting the depth of field value.

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail with reference to the accompanying drawings.

Description of drawings

FIG. 1 is a schematic diagram illustrating stereoscopic window violation.

FIG. 2 is a partial block diagram of an image processing device according to an embodiment.

FIG. 3 is a schematic diagram of obtaining a depth map according to an exemplary embodiment.

4A and 4B are schematic diagrams illustrating adjusting a depth-of-field map according to an embodiment.

FIG. 5 is a schematic diagram illustrating displaying a stereoscopic image according to an embodiment.

FIG. 6 is a flowchart illustrating a method for adjusting a stereoscopic image according to an embodiment.

【Symbol Description】

110: left eye

112: right eye

120, 122, 310, 320: Image

130, 150, 340, 430: objects

140, 410: screen

200: image processing device

210: Processor

220: memory

311, 321: feature points

330: Depth of field map

331: Location

350: area

420: Viewer

S602, S604, S606: Steps in the stereoscopic image adjustment method

Detailed ways

FIG. 2 is a partial block diagram of an image processing device according to an embodiment.

Referring to FIG. 2 , the image processing device 200 includes a processor 210 and a memory 220 . The image processing device 200 may be implemented as a computer, server, distributed system, television, smart phone, tablet computer, any form of embedded system or electronic device, and the present invention is not limited thereto. In an exemplary embodiment, the image processing device 200 may further include a screen, a wired or wireless communication interface, or a power supply, and the invention is not limited thereto.

The processor 210 is used to execute a plurality of instructions. For example, the processor 210 is a central processing unit (Central Processing Unit, CPU), a microprocessor (Microprocessor) or a digital signal processor (Digital Signal Processor, DSP).

The memory 220 stores a plurality of instructions, and the processor 210 executes these instructions. For example, the memory 220 is dynamic random access memory (dynamic random access memory, DRAM), static random access memory (static random access memory, SRAM), flash memory (flash memory), or other memory.

FIG. 3 is a schematic diagram of obtaining a depth map according to an exemplary embodiment.

Referring to FIG. 3 , the processor 210 obtains a stereoscopic image and obtains multiple depth values of the stereoscopic image. For example, the stereoscopic image includes image 310 and image 320 . The processor 210 obtains a plurality of feature points in the image 310 and a plurality of feature points in the image 320 , and pairs the feature points in the image 310 and the image 320 to generate a plurality of depth values. These depth values form a depth map 330 . For example, the processor 210 calculates the disparity between the feature point 311 and the feature point 321 , so as to calculate the depth value at the position 331 . The processor 210 may use any stereo matching algorithm to calculate the depth value on the depth map 330 , and the present invention does not limit which stereo matching algorithm is used. In another exemplary embodiment, the depth map 330 may be calculated by other electronic components or devices, and the depth map 330 will be sent to the processor 210 . For example, the processor 210 will obtain the depth map 330 and one of the image 310 and the image 320, and use a depth-image-based rendering algorithm (DIBR algorithm) to display the three-dimensional image, The present invention is not limited thereto.

Depending on the value of the depth of field, an object will be imaged in front of or behind the screen. If an object is imaged in front of a screen, the object's corresponding depth of field value is negative parallax. Conversely, if an object is imaged behind a screen, the depth of field value corresponding to this object is positive parallax. In this exemplary embodiment, a negative depth-of-field value is negative disparity, and a positive depth-of-field value is positive disparity. However, in other exemplary embodiments, the processor 210 may also use a positive depth value as a negative disparity, and the present invention is not limited thereto.

The depth values in the area 350 (also referred to as the first depth values) correspond to an edge area of a screen. The processor 210 determines whether there is a negative parallax in the area 350 or not. If there are depth values in the area 350 with negative parallax, the processor 210 will adjust all the depth values in the depth map 330 so that the depth values in the area 350 are not negative parallax. The width of the area 350 in this embodiment is one pixel. However, the width of the region 350 may also be more pixels, and the present invention is not limited thereto. It is assumed here that the depth of field value belonging to the object 340 in the area 350 has a negative parallax, that is, the viewer will think that the object 340 is imaged in front of a screen.

4A and 4B are schematic diagrams illustrating adjusting a depth-of-field map according to an embodiment.

Referring to FIG. 4A , the viewer 420 may think that the object 340 is imaged in front of the screen 410 , and that the object 430 is imaged behind the screen 410 . It should be noted that the screen 410 does not display the content of the object 430 , but the viewer 420 will think that there is an object 430 when viewing the image. For example, the viewer 420 sees the object 340 and the object 430 behind the screen 410 in the last stereoscopic image. In the next frame, the object 340 "jumps" off the screen 410, but the object 430 is covered. Therefore, the viewer 420 will feel uncomfortable. In this embodiment, the processor 210 adjusts all the depth values so that the depth values corresponding to the edge regions of the screen 410 do not have negative parallax (as shown in FIG. 4B ). After adjusting the depth of field value, although part of the object 340 is still in front of the screen 410 , the viewer 420 does not feel uncomfortable.

Please refer back to FIG. 3 , for example, the processor 210 will obtain a minimum depth of field value with the smallest value from the depth of field values of the region 350, and determine whether the minimum depth of field value is a negative parallax (for example, determine whether the minimum depth of field value is less than zero). Assume here that this minimum depth of field value is -50. The processor 210 adds an offset value to the minimum depth of field value to generate another depth of field value (also called a second depth of field value), so that the second depth of field value is not a negative parallax. For example, the offset value is 50, so the second depth of field value is 0. That is to say, the second depth of field value has zero parallax, and objects corresponding to the second depth of field value will be imaged on a screen. In addition, the processor 210 will add the offset value to all depth values except the minimum depth value, thereby "moving back" all objects in the stereoscopic image. In this way, the object 340 in the area 350 will not be imaged in front of the screen.

In this embodiment, the processor 210 adds the same offset value to all depth values. However, in another embodiment, the processor 210 may also add different offset values to different depth values according to the content, brightness or color of the stereoscopic image. On the other hand, in the above example, the minimum depth of field value is 0 after adding the offset value. However, in other embodiments, the minimum depth of field value plus the offset value may also be any positive number (ie, positive parallax), and the present invention is not limited thereto.

FIG. 5 is a schematic diagram illustrating displaying a stereoscopic image according to an embodiment.

Please refer to FIG. 5 . The upper part of FIG. 5 shows a schematic diagram of displaying a stereoscopic image before adjusting the depth of field value, and the lower part of FIG. 5 shows a schematic diagram of displaying a stereoscopic image after adjusting the depth of field value. The processor 210 appropriately changes the positions of the image 310 and the image 320 displayed on the screen 410 according to the adjusted depth of field value. It can be found from FIG. 5 that after the depth of field is adjusted, the disparity between the image 310 and the image 320 becomes smaller, so that there is no stereoscopic window violation.

FIG. 6 is a flowchart illustrating a method for adjusting a stereoscopic image according to an embodiment.

Referring to FIG. 6 , in step S602 , multiple depth values of the stereoscopic image are acquired, wherein the multiple first depth values correspond to edge regions of the screen.

In step S604, it is determined whether one of the first depth values is negative parallax. If the result of step S604 is no, then end this process. If the result of step S604 is yes, go to step S606.

In step S606, the above-mentioned depth of field value is adjusted so that the first depth of field value is not a negative parallax.

Each step in FIG. 6 may be implemented as one or more modules, and these modules are executed by a processor. Alternatively, each step in FIG. 6 may also be implemented as one or more circuits. The present invention does not limit the implementation of the stereoscopic image adjustment method by means of software or hardware. On the other hand, each step in FIG. 6 has been described in detail above, and will not be repeated here.

To sum up, the adjustment method and the image processing device proposed by the embodiments of the present invention can adjust the depth of field value when the depth of field value corresponding to the edge area is negative parallax, so that the violation of the stereoscopic window does not occur.

Although the present invention has been disclosed as above with the embodiments, it is not intended to limit the present invention. Those skilled in the art can make some changes and modifications without departing from the spirit and scope of the present invention, so the protection scope of the present invention The scope defined by the appended claims shall prevail.

Claims (10)

1. A method for adjusting a stereoscopic image, used in an image processing device, wherein the stereoscopic image is used to display on a screen, characterized in that the adjusting method comprises: obtaining a plurality of depth values of the stereoscopic image, wherein a plurality of first depth values among the depth values correspond to an edge area of the screen; determining whether one of the first depth-of-field values is a negative parallax; and If one of the first depth of field values is negative parallax, adjust these depth of field values so that these first depth of field values are not negative parallax. 2. The adjustment method as claimed in claim 1, wherein the stereoscopic image comprises a first image and a second image, and the step of obtaining the depth values of the stereoscopic image comprises: obtaining a plurality of first feature points of the first image, and obtaining a plurality of second feature points of the second image; and pairing the first feature points and the second feature points to calculate the depth of field values. 3. The adjustment method according to claim 1, wherein the step of judging whether one of the first depth of field values is a negative parallax comprises: obtaining a minimum depth of field value among the first depth of field values; and Determine whether the minimum depth of field value is negative parallax. 4. The adjustment method according to claim 3, wherein adjusting these depth of field values so that the first depth of field values are not negative parallax steps comprises: adding an offset value to the minimum depth of field value to generate a second depth of field value, wherein the second depth of field value is not a negative parallax; and The offset value is added to the depth values other than the minimum depth value. 5. The adjustment method according to claim 4, wherein the second depth of field value is zero parallax. 6. An image processing device, comprising: a memory storing a plurality of instructions; and a processor, coupled to the memory, for executing the instructions to perform a plurality of steps: Obtaining a plurality of depth values of a stereoscopic image, wherein a plurality of first depth values among the depth values correspond to an edge area of a screen; determining whether one of the first depth-of-field values is a negative parallax; and If one of the first depth of field values is negative parallax, adjust these depth of field values so that these first depth of field values are not negative parallax. 7. The image processing device as claimed in claim 6, wherein the stereoscopic image comprises a first image and a second image, and the step of obtaining the depth values of the stereoscopic image comprises: obtaining a plurality of first feature points of the first image, and obtaining a plurality of second feature points of the second image; and pairing the first feature points and the second feature points to calculate the depth of field values. 8. The image processing device as claimed in claim 6, wherein the step of judging whether one of the first depth of field values is a negative parallax comprises: obtaining a minimum depth of field value among the first depth of field values; and Determine whether the minimum depth of field value is negative parallax. 9. The image processing device as claimed in claim 8, wherein adjusting the depth of field values so that the first depth of field values are not a negative parallax step comprises: adding an offset value to the minimum depth of field value to generate a second depth of field value, wherein the second depth of field value is not a negative parallax; and The offset value is added to the depth values other than the minimum depth value. 10. The image processing device as claimed in claim 9, wherein the second depth of field value is zero parallax.