Helpless

Chapter 63

For the past few hours Rainy and Carter had tried without success to make sense of the disparate hash values of the images Mann had given them. They were examining four of Mann’s pictures. The girl Rainy had officially ID’d was Gretchen Stiller.

“Same composition,” Rainy said to Carter.

“Exact same.”

“So why don’t these images generate the same hash value?”

“The pixels aren’t the exact same, that’s why.”

“How so?” Rainy asked.

“Take a look at the color composition of the images when compared side to side. I’ve arranged them on my monitor screen to run from lightest to darkest.”

Rainy could see that each image was progressively darker than the previous one.

“So the colors aren’t the same. What do you know about color depth in computer graphics?” asked Carter.

“About as much as I know about caring for houseplants,” Rainy said. Her spider plants were almost ready for their last rites.

“Maybe if you used your home for something more than a glorified storage locker, they might be thriving,” Carter said.

“Back to the color depth,” Rainy said.

“The job is never going to end, Rainy. There’s always going to be bad guys out there. We can’t get them all.”

“As you were saying—”

“These images are moments in time that’ll last forever. You can’t say the same thing about your life.”

“The color depth, please, Cart,” Rainy said, more irritated this time.

“Right. Color depth in computer graphics describes the number of bits used to create the color of a single pixel. The higher the color depth, the greater the range of distinct colors that can be used.”

“And the connection to these four?”

“The precision to which color can be represented gets pretty technical. At the pixel level there are slight variations to color that aren’t visible to the naked eye, but that would change the hash values.”

“Where did Mann get these images?”

“Four different sources,” Carter said.

“So each source altered the pixel colors slightly?”

“It looks that way to me,” Carter said.

“Why would somebody do that?” Rainy asked.

“That’s the question we need to answer.”

Rainy’s cell phone rang. She answered it.

“It’s the coach,” Rainy said, covering the phone. Rainy felt a little pulse of excitement, which took her by surprise. She couldn’t believe how happy she was to hear from him.

What is wrong with you, Miles? Rainy scolded herself. He’s good looking and probably innocent, that’s what’s wrong. Bad combination.

Rainy listened to Tom talk for several minutes without saying a word. “Of course I will,” she eventually said into the phone. She ended the call and turned to Carter. “Lindsey Wells is missing,” she said.

“Missing? As of when?”

“Sometime between last night and this morning.”

“Why is Hawkins calling you?” asked Carter.

“His daughter, Jill, may have found the sext image collection on Mitchell Boyd’s computer.”

“What now?” Carter asked.

“You’re going to try to figure out why people would make slight alterations to the same image composition.”

“And you?”

“I’m going to check out a new lead for our James Mann investigation,” Rainy answered him. “And maybe, just maybe, help find a missing girl in the process.”