[1] Akiyama Sora

(Real World, December 24, 2015, Thursday, evening; Japan, Kyoto, Sora Akiyama's apartment)

Christmas Eve, the time to prepare for an appointment.

Tomoon Nanamiya is still dressed in the house. Akiyama, who had already changed his clothes, went to the utility room and took out a few spare telescopic sticks and a piece of cardboard, fiddled with it, assembled a sign, and fastened it to the back of the disc-shaped robot vacuum. Then, he planned the robot's movement route through the APP on his mobile phone, let the sweeping robot pass through the door of the room where Shichinomiya Zhiyin was, and finally pointed the mobile phone camera at the wall directly opposite the door.

As the cardboard as a shield moves through the doorway, the blurred light and shadow on the wall that is difficult to distinguish from the human eye constantly changes, and is captured by the camera, and then the figure of Tomoon Nanamiya sitting in front of the dresser appears on the screen little by little.

This is a commercial application of an algorithm from Boston University last year that allows a phone to capture blurry images on the rough surface of a wall and reconstruct an image of an object out of sight — as if the wall were a mirror. A slight fly in the ointment is that this technique requires a moving baffle to create a change in light and shadow.

"Alright, let's go!"

With a familiar voice, Nanamiya Tomoin walked out of the room. The everyday-style Lolita outfit is not a very flashy one, and with a scarf that is almost never absent, the demon king who changes to a style is still so cute.

Thinking like this, Akiyama stepped forward and gently hugged each other. Nanamiya rubbed comfortably on his shoulder, and then noticed the screen of his phone in his hand.

"This ...... Eh, is that the kind of image reconstruction technology that Sora mentioned earlier?"

"Well, I just used our robot vacuum......"

Laughing and coming to the garage, Nanamiya Tomoin suddenly patted him on the shoulder as if he had thought of something.

"Speaking of which,There's no such technology in the school city, right?"

"Really...... Although it is not appropriate to give them the software directly, I think that by only explaining the uncomplicated principle to one party, they should be able to develop their own technology very quickly. ”

……

[2] Yuta Tomigashi

(Real World, Friday, December 25, 2015, AM; Ancol Dream Park, Jakarta, Indonesia)

The bright sunlight shines through the leaves of the palms and broad-leaved ficus, casting shadows of different shapes on the brick floor, which is somewhat dull by the wind, sun and dust, and the slightly fishy sea breeze blows in the face.

Yuta Tomigashi and Yurokuka, the tomigashi, sat side by side on a low cobblestone wall at the edge of the pool, each with their bare feet in the water, boredom flapping on the water.

"It's hot...... And it's old and dilapidated, and it's not as fun as it sounds. The lover next to him tugged at the corner of his shirt, "Yuta, I'm bored." Let's get out of here. ”

During this winter vacation, Yuta Tomigashi booked a plane ticket with Yuroka Bird and Campha Tomigashi to go to Jakarta to reunite with his parents and sister who had not seen each other for a long time. My father's career is basically going well, my mother has a new job in the local area after working as a housewife for a while, and my younger sister Yumeha Tomigashi is also adapting to life here.

However, when jokingly recommending a date spot to him, his father apparently didn't think about the development of the park in the past two years - the last time he brought his mom and Yumeba here was two years ago.

Now, perhaps due to poor management, many of the rides are permanently closed or suspended. The contrast between the old equipment and the lush, vibrant tropical vegetation that surrounds them adds a sense of desolation to the park's landscape.

After they walked around, the sun gradually rose and the temperature became a little unbearable.

"Well, Rokuka, this is also unexpected. Yuta Tomigashi rubbed her lover's hair, "Since you think it's boring here, let's go somewhere else to play." ”

"It would be nice to be like in 'that world'—no, as long as it was like in a spiritual network. After a few small complaints, the little bird Yu Liuhua took the lead in getting up, "[The True Eye of the Evil King] is too weak in this world. ”

Seeing that the other party subconsciously touched the non-existent blindfold, Yuta Tomigashi couldn't help but smile. In a world generated by technology beyond human comprehension, they, the second-class patients chosen by the Galactic Federation, have gained new bodies and powers corresponding to their fantasies. Since then, the real bird Yu Liuhua has gradually "graduated" - or rather, after substantially possessing the [True Eye of the Evil King], the original gameplay that relied on words and brain supplements has become boring.

"Then it's up to us to work hard. Yuta Tomigashi took her lover's hand, "Next semester there will be a VR course, with the help of the spiritual network, to build a virtual world...... It doesn't have to be that far away. ”

……

[3] One party passes

(Forbidden World, January 20, 2014, Monday, afternoon; School City, Ruiyun Elementary School)

"On the one hand, what are you talking about as a new invention?"

In the activity room of the physics department, Ichibu and Mikoto Misaka were standing at the junction of the two compartments, and other members of the community gathered around, curiously looking at the mobile phone in his hand and the robot that was already equipped with a light shield on the ground.

"That's right. We all know that light on a rough surface like a wall scatters in all directions, so it cannot be identified by our eyes as a mirror, so it is certainly impossible to read information from it. ”

Speaking of this, Fang Tong pointed to the baffle erected on the robot's back.

"However, if a moving obstacle is placed in advance, the algorithm I designed with Misaka can start by reconstructing the shadow position of the obstacle and continue to reconstruct the hidden target image itself. Misaka-san, can you stand over there?"

Mikoto Misaka stood in another compartment, and then one side passed and pulled the movable door at the junction of the two compartments to 1.5 meters away from the wall at the end. Then, he attaches the phone to the stand, points the camera at the wall, and then activates the robot to move along a straight path, and Misaka's image slowly appears on the screen.

"Impossible......"

"Unexpectedly...... A place where you can really see the blind spots!"

"That's amazing!"

After a moment of surprise, there was an inquiry about the principle - there are many clubs in the school, and most of the students who choose to join the physics department are really interested in this aspect.

"Combined with the principles of optics, we built such a model......"

One party opens the laptop and projects the prepared content onto the wall: "When the occlusion is located at P-0 between the monitor and the visible wall, and the camera is located at a distance D, the irradiance of the wall at P-w is given by this formula...... where f(x) is the radioactive and integrated light energy of the monitor scene, and in the integrated function, we use such a weighting factor to simulate the radial attenuation of the magnetic flux density and two perspective effects......"

Well, looking at those unclear eyes, Fang Tong reluctantly admitted that these complex modeling is not a small challenge even for college students, and it is not feasible to make a group of ordinary elementary school students understand it thoroughly.

"Well...... Is this the mind of a superpowered and a powerful person? It's really not something we can reach!"

"The Mighty...... No, that, in fact, the main math work is done by one party. Mikoto Misaka shook her head a little embarrassedly, then smiled evilly, "But I also think this guy's mind is really weird - it's just a thing." ”

"Yes, yes, I'm a monster. It's been a year since he returned to the life of a normal person, and one party can be considered open in conversation, so he immediately countered, "Then you are the monster's confidant, Mei-Qin-chan!"

To the naked eye, the brown-haired girl's face flushed.

"Eh, you just called Misaka-san...... yes, right?"

"So your relationship has reached this point?"

"It seems that we have been together during the winter vacation. ”

Finally, with a flickering electric light, a embarrassed Mikoto Misaka kicked him against the wall.

"Don't make jokes about other people!

……

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Reference: How an ordinary camera can see around corners