WO2012115293A1

WO2012115293A1 - Method for converting a 2d image into a 3d image

Info

Publication number: WO2012115293A1
Application number: PCT/KR2011/001297
Authority: WO
Inventors: 홍순호; 김광욱; 이대희; 최광식
Original assignee: (주)스튜디오 로프트
Priority date: 2011-02-24
Filing date: 2011-02-24
Publication date: 2012-08-30

Abstract

The present invention relates to a method for converting a 2D image into a 3D image in order to enable the viewing of a stereoscopic image, and more particularly, to a method for creating left-eye and right-eye images through a lighting effect and displacement effect using a depth map in addition to a lens-blur effect.

Description

【Specification】

[Name of invention]

How to convert 2D images into 3D stereoscopic images

Technical Field

The present invention relates to a method of converting a 2D animation into a 3D image by a 3D stereoscopic conversion method, and a method of stereoscopically working a 2D animation into a 3D animation.

Background Art

A person feels the body by looking at an object from different angles in his left and right eyes. In order to realize and provide a 3D stereoscopic image based on this principle, a stereoscopic image is artificially displayed by displaying two images, which are taken separately from the left and right eye visual positions, respectively. Implement

However, in order for the conventional technology to be effective, the image to be seen by the left eye and the image to be seen by the right eye must be present as described above. There was a difficulty to produce. This means that many existing two-dimensional images (including animation) cannot be used in stereoscopic image implementation system.

In particular, when converting 2D animation into a 3D image, it is a picture that does not create a sense of volume (three-dimensional feeling) due to the characteristics of a picture. As such, two-dimensional images such as animation have more difficulty in converting to a 3D imager than a general image. This is because conventional 2D animation does not generally include not only lighting effects but also stereoscopic effects. In addition, it is because it is not easy to predict lighting effects and stereoscopic effects.

Accordingly, the present invention has been invented to solve the above problems, and its object is to convert a general two-dimensional image material, preferably a 2D animation into a 3D animation. '

[Content of invention]

Alternative Paper (Article 26) As used herein, a depth map refers to a contrast image showing a depth value of an object on a 2D image. It is a map of the reference image to indicate the part far from the viewer. For example, in the present invention, the portions near the viewing side are white, the far portions are black, and each position is expressed in a gradient manner of white and black according to the perspective from the viewing side. 1 and 9 are exemplarily referred to. For example, in FIG. 1, the depth map of the original lamp, etc., is shown in white because the convex part of the original lamp, etc. corresponds to the closest part when looking at the original lamp, and is based on the most blocked part of the original lamp. When you look at it as the left and right gradually get darker in a gradient way. This is used as a basis for the movement of the pixels of the original image, for example, the application of the displacement map effect, which will be described in detail below. As used herein, "in the manner of white and black gradation" means the difference in height (perspective difference on the viewing side) of each pixel in the image, the color between white and black, ie the distance away from the camera. It means that the difference is expressed.

According to the present invention, a method of converting a 2D image into a 3D stereoscopic image, in which a highlight portion that receives the most light is white and a portion that does not receive light is displayed in white and a black gradation method in the 2D image. Forming a lighting layer; Forming a depth map layer in which the portion closest to the viewing side is displayed in white, and the portion furthest from the viewing side is in black, displayed in a gradient manner of white and black; Based on the white and black gradation values of the depth map, the pixel of the image for the right eye image is shifted to the left, and the pixels of the image for the left eye image are shifted to the right. It relates to a method of converting a 2D image into a 3D stereoscopic image, which is moved to the largest range of the predetermined range, and the black portion is moved to the smallest range of the predetermined range.

In addition, in order to further increase the stereoscopic effect, the present invention may provide a minimum blur effect to a portion closest to a focal length to the left and right eye images, and include a maximum blur effect to a portion farthest from the focal length. .

[Brief Description of Drawings]

1 is a magnified depth map image of a 2D image of a circular shape.

2 is a light effect applied to a 2D image of a circular shape, which is divided into pixels. FIG. 3 is an image divided before the lighting effect is applied to a cylindrical 2D image, and is divided into pixels.

4 is an image in which the image of FIG. 2 is arranged side by side.

FIG. 5 is an image in which a displacement map effect is applied and pixels of an image are shifted based on the depth map of FIG. 1. FIG.

6 to 9 are images showing a depth map generation process by a mask.

10 is a view for explaining the principle that a stereoscopic image is projected onto a flat film to form a 2D image.

11 is a view showing a state of seeing an object with both eyes.

12 is a view for explaining the principle of making the right eye and left eye images. 13 is a flowchart showing a method of converting a 2D animation of the present invention into a 3D animation.

[Specific contents to carry out invention]

As referred to in FIG. 13, the method for converting the schematic 2D animation of the present invention to 3D animation is as follows. Extract the target images from the original image, increase the size only larger than HD (e.g. 3840 x 2160), leaving the resolution of the old film (e.g. 640 x 480) (resize). Print the extracted and resized image directly on the drawing paper, and correct the pencil lines and color parts on the printed image. Scan the corrected image at high resolution using a scanner, FULL HE ⁾ for 3D TV. Therefore, scan at the appropriate resolution, eg 1920 x 1080. Scanned image files can be loaded from a computer image editing program such as Photoshop or After Effects.Nuke.Cinema 4D to insert image lighting effects using separate layers. This will be explained in detail below.

Meanwhile, a depth script and a depth map are generated based on the image file scanned at the high resolution. The depth map will be described in detail below. Based on the created depth map, a displacement map effect is generated to generate left and right eye images, which will be described in detail below. The left and right eye images are corrected and subsequently a stereoscopic image is generated and stored as a 3D animation image. Below is an illumination layer of the present invention; Depth map layer; And a representative example of implementing pixel movement as an example.

1. Insert lighting effects (create lighting layers)

A feature of the present invention is to add a lighting effect using a gradation to implement a three-dimensional effect on a 2D image. In the conversion of 3D animations from conventional 2D animations, I could not think of inserting lighting effects, but simply shadowed them. The inventors of the present invention have found that the insertion of the lighting effect enables proper implementation of the three-dimensional effect. Accordingly, the inventors have applied the effect of the lighting to further increase the three-dimensional effect in the 2D animation. The method of applying this lighting effect was implemented by the method introduced in detail below. Thus, the lighting effect was applied to the solid surface, which is a characteristic of 2D animation, to create a change in color. Such addition of the lighting effect of the method using the gradation of the present invention allows the three-dimensional (volume) to be properly alive. However, if the effect of the lighting is too strong there is a risk of changing the original slow, it is preferably taking the way to maximize the feeling of the original by giving a lighting effect of less than 50%. 2 is an exemplary diagram to add a lighting effect of the method using a gradient.

1.1. How to put lighting effects (Brush lighting)

Referring to FIG. 2, reference may be made to an example in which a lighting effect is added. Image overlays that have finished layer separation or finished resolution enhancement, create one or more layers in Photoshop, and highlight the highlights with a brush to apply a white overlay effect. The darker shadows ("shadows" in this specification do not mean the shadows of the actual image, but the darker areas that are opposite to the direction the light is coming from). The highlight and darkening shadows are selected by considering the direction of illumination from the target image. The boundary between the highlight and the shadow portion gives a feather effect, making the gradation smooth and natural. Wherein the feather value is preferably 4-6. Transparency was applied to the layer so that this effect was applied quietly. Preferably the transparency value is 50%. Referring to FIG. 2, it can be seen that the left side shows the bright highlight part and the shadow part I becomes darker toward the right side. That is, the original image of the main lamp has a light coming from the left, and thus the left of the main lamp. The side part corresponds to the bright part (highlight part), and the right part corresponds to the dark part (shadow part), and FIG. 2 expresses the lighting effect on the 2D image of the energy lamp by utilizing the gradation.

1.2. How to put lighting effects (lighting by mask)

The brush effect described above was created using a mask and a pentle, which are basic functions of a video effects program (After effects. This method works even if the layers of the original source are not separated. I created a solid layer on top of the original source image and masked the highlights or shadows with a pen. At this point, the mask line is precisely cut with a knife, but the edge outline is smoothed and made natural as described above. For example, it was a feather value of 4-6. 6 to 9 may be referred to.

2. Create the depth map

6 to 9 are referred to for the depth map operation. In the present invention, the portion near the viewing side is expressed in white and the portion farther in black. To implement this, a separate black layer was created (FIG. 6). On top of that I made a white layer on the closest part of the object (Figure 7). After the white layer was made, contours representing depth were made in frame units using a pentle. As described above, by adjusting the feather value of the mask (feather value 4-6), a natural and smooth gradation was created (FIGS. 8 and 9). FIG. 1 is an example of a depth map made in this manner. 1 shows a depth map with respect to an original light etc. as already demonstrated.

3。 Depth generation method using depth map

Usually, a 2D picture is not seen in three dimensions because it reflects the three-dimensional surface on the two-dimensional plane (film in FIG. 10) as shown in FIG. The reason why a person feels things three-dimensionally is because they observe things with the eyes of two people (FIG. 11). Therefore, to express a picture in three dimensions requires two pictures viewed from two viewpoints such as the human eye. If there is an original image, as shown in FIG. 12, creating a left eye image is an image of turning the original to the right, and a right eye image of an image of turning the original to the left. But because you can't actually turn it, you have to move the pixels left and right. At this time, the person who looks close to the eyes Since the protruding part of the water is close to the eye, the movement distance should be the largest when viewed only with the left and right eyes, respectively, and the part of the object farthest from both eyes will have the smallest movement distance. Therefore, when making an image of the right eye viewed from the right eye and the left eye viewed from the left eye, move the part closest to the eye more and move the part farthest farther away. Since the close part is black and the dark part is far from the eyes, when creating the right and left eye images using the depth map, the degree of pixel movement is increased by moving the white part by using the created depth map and by moving the dark part by less. By the three-dimensional effect can be implemented (applied with the display map effect), the generation of these left and right eye images is described further below.

To move the pixels of the original image in this way, Photoshop or a video effects program was used. Using the generated depth map, the effect was given a displacement map effect. Such displacement map using the white color to a black gradation data of using the effect of (Displacement Map), by appropriately moving the position of the pixels using _the> depth map is given a three-dimensional effect.

4. Create left and right video

Referring to FIG. 4, the original images to which the lighting effect is applied are arranged side by side. The left eye image was placed on the right side and the right eye image on the left side. A depth map of the corresponding image (depth map of FIG. 1) is placed under the image, and then a displacement map effect is applied to the original images arranged left and right. The displacement map affected by the depth map moved the original pixels. The bright pixels in the depth map were shifted to the left by giving a positive value to the left eye image. Bright pixels in the depth map were shifted to the right by giving a negative value to the original to be the left eye image on the right. That is, as shown in FIG. 5, the pixels of the right eye image move to the left and the pixels of the left eye image move to the right. As described above, in the right eye image and the left eye image, the direction in which light colors move and the direction in which dark colors do not differ is different, but the distance moved is a lot of light colors and dark colors move slightly.

5. Lens Blur In order to maximize the sense of distance (depth), the present invention considers the addition of lens blur. The closer to the focal length, the sharper the distance from the focal point and the greater the blurring value, and the pixel movement caused by the depth map. The added three-dimensional effect is further maximized by blurring.

If the lens blur is applied to the left eye and right eye images, the bright part receives the most blur and the dark part receives the less blur due to the influence of Thamesblind.If you check Invert in the option of the lens blur, The blurring value is the smallest, and the blurring value of the dark part becomes larger. In addition to the effects for representing the three-dimensional effect described above, the air (atmosphere) expression can also maximize the sense of distance (depth). In general, the distance between objects is expressed simply by spreading them from side to side. One of the methods used to draw animated backgrounds is to express organisms affected by light in the air. For example, there is sunlight that leaks through a window. You can add a layer of organisms affected by light to maximize the distance (depth). The expression of the layer is invisible, but the difference in depth with and without the layer is visible.

Although described above by way of example only, it will be understood by those skilled in the art that the present invention may be variously modified and changed without departing from the spirit and spirit of the present invention as set forth in the claims below. will be.

Claims

[Patent Claims]

[Claim 1]

As a method of converting 2D images into 3D stereoscopic images,

In the 2D image, the highlights that receive the most light are white, the areas that do not receive light are black, forming an illumination layer that is displayed in a white and black gradient.

The depth closest to the viewing side is shown in white, and the farthest away from the viewing side is in black, forming a depth map layer that is displayed in a gradient between white and black.

Based on the white and black gradation values of the depth map, the image for the right eye image is shifted to the left and the image for the left eye image is shifted to the right, wherein the white part in the movement is the largest of the predetermined ranges. Moved to a range, and the black portion moves to the smallest of the predefined ranges,

How to convert 2D images into 3D stereoscopic images,

[Claim 2]

The method of claim 1,

In the left eye and right eye images, a minimum blur effect is given to a portion closest to a focal length, and a maximum blur effect is given to a portion farthest from a focal length

How to convert 2D image into 3D stereoscopic image.