Tyson Frost sat up from his laptop keyboard the moment Grace walked into the CSI office.
“You heard?” he asked, tentative.
“About Daniel?” Grace said, nothing in her voice. “Yes. His mother called me last night.”
“Oh.” He shuffled his fingers. “Look, I’m really sorry—”
“You don’t have to say anything. Let’s just concentrate on work, hm?”
“Oh,” he repeated, fumbling with awkward relief. “Well, erm, you remember that clip of the girl’s neck you asked me to have a look at?” He punched a few keys and twisted the laptop to face her. “I think I’ve got something for you.”
On the screen was a wire-frame outline of a female figure. Frost brought up the image of a handprint alongside it, which Grace recognised as Jim Airey’s by the missing finger, and juggled the two together so the hand shrank and rotated, fingers closing round the girl’s throat.
Frost gave her a sideways grin and the hand tightened almost to a fist, making the figure suddenly dance and jerk. Grace smiled in spite of herself, cuffed his shoulder.
“Sorry,” he said, sheepish, returning the image to a more normal aspect. “Basically, though, it’s not a match. Even without the missing digit, his hand’s too small for the bruising.”
“So, if Airey didn’t try to throttle his own daughter, who did?” she wondered aloud. She put her bag down slowly, still frowning, then turned back to Frost. “How’s that 3D imaging software on facial recognition?”
“Not bad.” He leaned back in his chair and swivelled slightly. “Depends what you’re doing with it, I suppose. I mean, they’ve been trialling a system linked into all the CCTV cameras in one of the London boroughs, but as far as I know, it’s never identified anybody fully auto.” He shrugged. “If your target’s not obliging enough to be looking full at the camera, in more or less the same lighting conditions as your comparison photo, well”—he shrugged—“there’s still no real substitute for the human eyeball.”
“Shame,” Grace murmured. She’d captured the best images she could from the footage Nick had given her of the four men in the hotel lobby. Three of them, she felt she’d picked out quite successfully, but the fourth remained a more elusive figure. “I need to identify these men.” She handed over the best printouts of the covert mugshots. “They might be connected to our case. I was hoping it would save legwork.”
Frost leafed through them. “Video stills?” He pursed his lips.
“From a hotel security camera,” she agreed. “They went for coverage at the expense of clarity, so it’s got quite a fisheye lens on it.”
“Hm, I can try using a standard biometric facial recognition application, I suppose.” He frowned, flashed her a quick look. “Yeah, I might be able to do something with these. Have you got the original footage?”
Grace reached into her bag and pulled out the video cassette. His eyebrows climbed. “Wow, old school.”
“Won’t the distortion of the lens confuse the program?”
Frost shook his head. “As long as there’s something with known parameters somewhere in-shot, I can use the photogrammetry application to un-distort it,” he said, hurried. “That will give me a set of parameters to work with, then I can apply the same correction factors to the images of your guys, make a pass through FIND. That’s—”
“The Facial Images National Database. I do read the memos.” Grace couldn’t help smiling at his obvious enthusiasm. “I just thought it was still in the experimental stage, and I didn’t know Cumbria was taking part in the pilot scheme.”
“Ah.” Ty studied his fingernails. “Strictly speaking, we’re not.”
“Ah,” Grace echoed solemnly, sitting at her own computer and firing it up. “Oh, by the way, on your recommendation, I watched Fight Club last night.”
Ty squirmed. “You did?” he asked, reddening. ‘Oh, I, erm, only mentioned because of the digital effects.” His Adam’s apple bounced, convulsive. “I mean, erm, I wouldn’t have thought it was your kind of thing, and—”
“I thought it was a strikingly thought-provoking piece of film-making. Probably David Fincher’s best work as a director since Se7en.” She turned back to her computer screen so he wouldn’t see her smile. “And a wonderful opportunity to see Brad Pitt with his shirt off…”