176828.fb2 The Long shot - читать онлайн бесплатно полную версию книги . Страница 7

The Long shot - читать онлайн бесплатно полную версию книги . Страница 7

Howard nodded. “He was a real-estate salesman, he used it to make videos of properties he was selling.”

“Ah, that explains it,” said Bonnie. “We’re lucky he had it, because anything less powerful and we probably wouldn’t see half the details we have. You can make that pixel as large as you want, it’ll still be one unit. You’ll just have a big pixel. What neighbourhood averaging does is to smooth out the image by taking an average of the colour and brightness of individual pixels in a predefined area. There was an improvement in the clarity of the images, but the edges blurred and we actually lost some detail, which was to be expected. Median filtering is a similar computer technique, but it uses a median value instead of an average value. It’s a small difference, but a significant one. I ran through a three-by-three neighbourhood and then a five-by-five, right on up to a nine-by-nine. For the worst areas I’d like to use the technique I mentioned, pixel aggregation. You choose a pixel which has properties you can clearly identify in terms of colour or texture and then you gradually move outwards, adding to it pixels of matching qualities, until you grow a defined region. That produces clusters of matching pixels, which can then be highlighted. I’m afraid it’ll take me quite a while with the equipment I have.”

Howard continued to go through the photographs as he listened to Bonnie’s explanation, most of which went way over his head. One of the pictures showed a row of bald, naked figures. “What are these?” he asked.

“Yes, I’m quite proud of those,” she said. “You could barely see them in the original, and the camera only picked them up once, but they’re there all right. They’re what the snipers are aiming at. Four dummies. The sort used in shop window displays.”

Howard put two photographs on the bench. They showed two sedan cars and a large flatbed truck. “I didn’t see these in the video,” he said.

Bonnie nodded eagerly. “They were only there for a few seconds, when the plane was spinning. The quality isn’t good, but you can see the colour and make. They’re Chrysler Imperials, one blue, one white. The truck I’m not sure about. Could be a Dodge.”

“That’s good, really good,” said Howard. He made a mental note to ask the Sheriff’s Department about tyre tracks at the scene.

The next set of pictures showed a group of three people standing together, a middle-aged man with a paunch, a young man, and a woman. The older man was holding something in his hand. There was a magnifying glass on the bench and Howard used it to examine the object.

“It’s a walkie-talkie, I think,” said Bonnie. “I assume he used it to keep in contact with the snipers.”

“Is there any way of magnifying the photographs any further?” Howard asked.

Bonnie shook her head. Her long braid swung from side to side like a rope. “I’ve taken it as far as I can,” she said. “I can make the images bigger, but I don’t have the software necessary for the sort of filtering that would make them any sharper. You should try one of the Japanese firms. Sony, or Hitachi. They should have the computers geared up for it. Or you could try firms working on artificial intelligence or robotics.”

“Robotics?” queried Howard.

“Robotics companies are big on artificial intelligence, and that’s the sort of expertise you’ll need. The pictures can be cleared up further by the application of algorithms using what are called the Hough Transform and Fourier Transform, and I can tell you which experts would be able to do that. A computer with some form of artificial intelligence could compare adjoining pixels and correct for abnormalities based on an assumption of what it’s looking for.”

Howard frowned. “I don’t follow.”

“Well, if the computer knows it’s looking at a face, it will know that an eye has a certain shape, so has a nose, so has a chin. It has to know whether a dark patch is a moustache, a nostril, or the pupil of an eye. It has to know that human bodies are made up of curves, but that mechanical objects are usually flat surfaces. If it’s looking at a licence plate, for instance, it must know to look for numbers and letters and not abstract shapes. I’m sorry, Agent Howard, I’m not explaining this very well.”

“Cole,” he said, “please call me Cole. And you’re doing just fine. Actually, I know someone who has access to the sort of technology you’re talking about.”

“Really?” she said. “Who would that be?”

“Clayton Electronics.”

Bonnie raised her eyebrows. “They’re good. Of course, their head office is in Phoenix, I’d forgotten. Why didn’t you go to them first?”

Howard stacked the photographs together and slid them back into the file. “We wanted to keep it within the FBI as much as possible. You’ve seen the video, you know what the implications are.”

Bonnie lowered her eyes and her cheeks reddened like a guilty schoolgirl. Howard wanted to ask her what was wrong but felt that she’d shy away from such a direct approach. He waited for her to tell him what was troubling her.

“I had an idea,” she said, still avoiding his eyes. “Well, not my idea, really. It was my husband’s.”

“Your husband?”

She nodded and raised her head. “He’s a mathematician. A PhD. He specialises in computer graphics.”

Howard was bemused, but he listened attentively. Bonnie Kim was clearly very intelligent and anything she had to offer on the case could only be of help.

“I was explaining about the video, about the three men with rifles and the towers, and he said it would make an interesting computer model. You could program the coordinates of the men and the targets, and get a 3-D structure representing their positions.”

Howard understood why she’d been embarrassed. She’d told her husband about the video, and was now worried she’d breached security. He wanted to tell her that it was okay, but he didn’t want to interrupt her. Her eyes were shining with enthusiasm. “You work out the heights of the towers, you calculate the angles and distances to the target, and then you superimpose that model on all the different venues where the target is due to appear.”

Howard tapped the file with his fingers. “He could do that?”

“He could do the preliminary work, sure. I haven’t shown him the video, but if I did he could put together the model, he said. He’d need to know the exact time of day the video was shot, so that he could use the shadows to determine heights and so on, and he might have to go out to the site to make some measurements, but yes, he could do it.”

“What about the venues? How would he get those into his computer?”

“You’d need street plans and the heights of the various buildings. He could customise a program for you, but it would take a lot of work to input the information. Once it’s in, though, the program would produce a 3-D model of the area, and it could then superimpose the snipers and target on it. It would tell you if the snipers were preparing for that venue or not. And if the models do fit, it’ll tell you exactly where the snipers will be. It’s a brilliant idea.”

Howard smiled. “It is. Your husband’s a very clever man. We do have one problem, though. At the moment we don’t know who the target is.”

Bonnie’s mouth opened, showing perfect white teeth. “Oh. I just assumed. .”

“That it was the President?”

She nodded. “You think it’s someone else?”

“Bonnie, we just don’t know. But your husband’s idea is a good one. We know the President’s itinerary well in advance; if he can set the program up for us, I can bring in extra manpower to do the inputting.”

“So I can tell him to go ahead?”

“Sure.”

Bonnie positively beamed. “He’ll be so pleased. He thinks it’ll be like a detective story. He suggested I ask you to come to dinner with us, tonight. I’ll cook, and he can go over the details with you.”

It was an offer Howard couldn’t refuse.

Andy and Bonnie Kim’s house was a spacious single-storey ranch house in a quiet suburban road to the north of Washington. The grass was neatly cropped, the paths were edged with orderly flower beds and the Stars and Stripes fluttered from a white flagpole. Two cars were parked outside when Howard arrived: a Buick Roadmaster and a Cherokee Laredo, and when Bonnie Kim opened the front door and let him in he could see that the interior was just as all-American. It wasn’t what Howard expected at all. He’d always assumed that Koreans stuck closely to their heritage, but the Kims seemed to want it made clear to everyone that they were Americans through to the core.

Andy Kim had a round, smiling face and a mop of black hair which was continually falling over his eyes. He was as tall as Howard, but much thinner, and his horn-rimmed spectacles gave him a bookish appearance. He shook hands with Howard and asked him if he wanted a beer. Howard said he’d prefer an orange juice and Andy led him through to the living room while Bonnie went to the kitchen. Bonnie had changed from her working clothes into a floral print dress with a white collar and she’d let her hair loose so that it flowed around her shoulders and down her back. She looked impossibly young and he realised that she probably adopted the more severe look in the laboratory in order to be taken more seriously. She’d lost the high heels too and now stood just a little over five feet tall.

Howard sat down on a long sofa and looked around the room. One wall was lined with bookshelves, a mixture of scientific books, romances and thrillers, all of them in English. On a coffee table were copies of Scientific American, Fortune and several computer magazines. The large-screen television was on but the sound had been muted. The Washington Redskins were playing.

“Do you want to watch the game?” Andy asked.

“I’m not a big football fan,” replied Howard.

“Really? I love it. There’s a lot of mathematics in football, you know?”

Bonnie came into the room carrying a bottle of Budweiser for her husband and a tall glass of orange juice for Howard. “Dinner’s ready,” she said, “come on through.”

Before he’d stepped into the house, Howard had expected that Bonnie would cook Korean food for him and that he’d have to deal with chopsticks but having seen the interior he wasn’t in the least surprised to see that Bonnie had prepared steak, french fries and ears of white corn. After the meal, Bonnie served them coffee and all three of them went into the study, a wood-panelled room with several workbenches which were stacked high with electrical equipment and computers. Andy sipped his coffee as he switched on one of the machines. “I’ve done a little preparatory work already,” he said. “I hope you don’t mind.”

“No problem,” said Howard, sitting on a stool and watching as Andy’s fingers played across the keyboard.

“These graphics are really simple, but they’ll give you an idea what I have in mind,” said Andy. Two circles appeared on the screen, green on a black background. Andy pressed another series of keys and the circles were replaced by two figures, one a man with a rifle, another a standing figure. “Okay, suppose we have one sniper, and a target. And suppose the distance between them is five hundred feet, and the angle is ten degrees.” His fingers tapped at the keyboard and the picture became three-dimensional, with a dotted circle above the target. “We know that the sniper must be somewhere along this line,” Andy continued. “Now, if we superimpose the sniper’s possible positions on a city plan. .” Several square and oblong shapes appeared on screen in various colours. “I know, they don’t look like buildings, but you get the drift,” he said.