A painting. If you watch it quietly for a while, you will see a strange scene behind it. What's this picture called?

Three-dimensional stereogram Stereographic painting is a painting made by using the stereoscopic vision phenomenon of human eyes. Ordinary paintings and photographic works, including computer-generated three-dimensional animation, only use the light and shadow of human eyes, light and shade, sense of reality and falsehood to obtain three-dimensional sense, but do not use the stereoscopic vision of eyes. One eye and two eyes are the same. Make full use of binocular stereo vision, and you will see a wonderful world.

First, the principle of stereoscopic vision and stereoscopic painting. People have two eyes, and there is a certain distance between them, which causes some differences in the images of objects in the eyes. See the right picture. As can be seen from the picture, because the distance between the object and the eyes is different, the visual angles of the two eyes will be different, and what they see will be different because of the different visual angles. According to this difference, the brain will feel the three-dimensional scene.

Cubic painting uses this principle to produce a series of repeated patterns in the horizontal direction. When these patterns overlap in two eyes, you will see a three-dimensional image. See the picture below, this is a three-dimensional painting that can't be simpler. In the picture, the top circle is farthest and the bottom circle is closest. Please note that the distance between the circles in the top row is the largest and the distance between the circles in the bottom row is the smallest.

How did this happen? Let's look at the picture below. As can be seen from the figure, the distance of the repeated pattern determines the distance of the stereoscopic image. Based on this principle, the program for generating stereoscopic pictures generates repeated patterns with different distances according to the distance of stereoscopic images.

Second, the appreciation of stereoscopic paintings If you can't understand stereoscopic paintings now, are you already in a hurry? Next, I will introduce how to read three-dimensional paintings.

There are two forms of stereoscopic painting: the first is the same pattern arranged at different intervals in the horizontal direction, which looks like objects with different distances. Please look at the picture below. This three-dimensional painting can be made by any kind of image processing software, such as Photoshop and Windows brush. You can also try.

Another kind of stereoscopic painting is more complicated. You can't directly see the image of the object on this stereoscopic painting, there are only messy patterns on the screen. To make this kind of three-dimensional painting, you have to use procedures. I have written some programs for this, including the source programs of C and QBASIC. Please see the homemade three-dimensional paintings and program downloads. The views of the two works are the same, and the principle is to let the left eye see the image of the left eye and the right eye see the image of the right eye. (Some people say: Isn't this nonsense? Listen to me: When you look at a three-dimensional painting, you should imagine that you are admiring the artwork in the glass window. That is to say, you should not look at the three-dimensional painting on the screen, but look at the screen as the glass in the glass window, and you should look at the image inside the glass.

Third, the two-point practice method, please aim at the two points at the top of the picture below, let your eyes rest for a while, then aim at these two points with a slightly blurred line of sight like looking at the distance, you will see that the other two points are separated, and then adjust your line of sight to try to combine the two points inside. When four points become three points, you will see a three-dimensional image.

Four, another way to watch from the computer, you can do this, if the picture is marked with two points (if not, you can watch carefully, in the horizontal direction, about 3-5 cm apart, there are the same patterns, such as two points of the same color and size. ), then you can use two dark lines to stick them vertically on the display screen (you can enter the screen a little), so that the two lines are vertical and connected to two points respectively. Then, put a small object above the back of the display as a reference object, look at the reference object along the upper edge of the display, and move the focus of the eyes back and forth so that the left eye, the left line and the reference object are in a straight line, and the right eye, the right line and the reference object are in a straight line, which can be adjusted by blocking one eye. Then look at the reference object with both eyes, and the two lines become three, so that you can see the three-dimensional effect by climbing the middle line.

Generally speaking, stereoscopic images make use of the principle of visual difference and optical refraction of human eyes, so that people can directly see a stereoscopic picture on a plane. Things in the picture can highlight the picture or be hidden in the picture, which is vivid and gives people a strong visual impact. It is essentially different from the plane image, which reflects the two-dimensional relationship between objects up and down, left and right, and the plane image people see also has a three-dimensional sense. This is mainly reflected in the contrast between light and shadow, reality and light and shade. The real three-dimensional painting is the principle of simulating people's eyes to see the world. It is made by optical refraction, so that the eyes can see the three-dimensional relationship of objects. It is a stereoscopic painting in the true visual sense.