Chapter 1356

Jiang Yuan actually used what method for image enhancement? On site, only two technicians from the provincial department cared, because they were the ones who would actually use it.

However, the two were roughly at a practical level, probably around LV1, enough to boast about reaching LV2.

But when Jiang Yuan kept changing plans and finally output several different versions of the same fingerprint, the fingerprint experts on site gathered around.

The same fingerprint, the details of the ridge lines became clearer and richer, and at the same time, the change in contrast also obviously improved the image quality.

This was an unmistakable change, a change that could be directly utilized; anyone who had studied fingerprints even a little knew how much help this gave to difficult fingerprints.

Li Zeming, envious, snatched a whole pack of Zhonghua cigarettes from Jiang Yuan's desk, took a hard drag, then shook his head and went back to his seat to get busy.

Other fingerprint experts looked around and then each went their separate ways.

"Huh, not going well?" Zhang Liming, who had been watching with a smile, asked anxiously.

"Going well." Li Zeming exhaled with faint dark circles: "Just not interesting."

Zhang Liming immediately relaxed, smiling: "Going well is fine. Comparing fingerprints is inherently dull."

"I don't mind dull." Li Zeming hummed twice: "We can't play Jiang Section Chief's game. His ridge details are enough for Level Three feature comparison."

"Level Three feature comparison, how so?" Zhang Liming asked curiously.

Li Zeming took a light puff and exhaled: "Level One feature is ridge characteristics—arch, loop, and whorl—ordinary people can tell at a glance. Level Two feature is the feature points we usually use: hook, eye, rod, bridge, dot. Level Three feature refers to the microscopic details of the fingerprint, including the edge morphology of pore ridges, ridge width and narrowness, fine point count, and pore characteristics; this basically requires high-resolution clarity to be usable."

Li Zeming pursed his lips again: "The clarity of the fingerprint Jiang Yuan is extracting now is sufficient for that."

Zhang Liming suddenly understood, then straightened his face: "I seem to have heard someone from the ministry mention this technical promotion before; it should still be difficult, right? Is it a high-resolution clarity issue?"

Li Zeming nodded: "The advantage of Level Three features is that you don't need such a large fingerprint area; even if the fingerprint is partial, as long as the clarity is enough, even a tiny area can be used for comparison. The problem is..."

Li Zeming smiled: "Our fingerprint database doesn't have that high clarity. So, it can only be used for secondary comparison."

"Secondary comparison is fine too." Zhang Liming immediately understood, stopped mentioning promotion, and said: "In other words, once we find a suspect, we can use Level Three features to compare again and know if it's the real culprit."

"Theoretically, that's how it is." Li Zeming nodded slowly, hesitated a moment, then said: "Academically, this issue is still debated. Especially the extraction and matching of Level Three fingerprints—difficulty is relatively high; ordinary technicians operating it tend to make more errors. Look at what Jiang Yuan did and you'll see."

Zhang Liming suddenly realized: "You all can't do it, so it's not interesting?"

He roasted beef eyes because he only cared about people who liked eating beef eyes; whether those who didn't like eating beef eyes were happy or not, he didn't care.

Li Zeming was made to laugh by Zhang Liming: "I can do Level Three fingerprint extraction and matching, but image enhancement is another specialty—besides someone like Jiang Yuan, ask who else can do it."

Zhang Liming looked left and right—indeed, not a single person raised their head in demonstration.

"No need to look; domestically, you can't find more than a few such talents." Li Zeming pursed his lips: "Those with this ability are snatched by internet giants, Hollywood companies, game companies—annual salaries of a million are no problem."

Saying that, Zhang Liming understood, pulled out his phone, and blurted: "Save those beef eyes from the slaughterhouse for me, and some beef too—they slaughter cattle at midnight, right? Just send it over when the meat is still twitching. How is it called 'twitching beef'? You don't watch food videos? It's that meat when the cattle have just been slaughtered and the nerves are still twitching."

Zhang Liming was speaking loudly on purpose; when he put down his phone, the experts in the room also heard.

He can't come up with a million-yuan annual salary, so he'll just use beef eyes as compensation.

At this moment, Jiang Yuan was also finishing refreshing the fingerprints on screen, pressed print while turning back: "No more eating, I'll work another two hours and then need to go sleep. Liu Zhi, trouble you to send someone to take fingerprints from these people; after I wake up, we'll compare again, just as Li Dui said—take high-clarity fingerprints, capable of Level Three comparison."

Liu Zhuang swore and ran over immediately. This arrest mission was undertaken by Anwan City Bureau, and the bureau assigned the task to the Anwan City Criminal Police Detachment.

Zhang Liming waited nearby, eager. He had waited so long for this; he immediately asked: "Did we get a hit? Did we hit a murder case?"

For any fingerprint showdown, hitting a case fingerprint doesn't count as failure.

Think about it—you know that fingerprints eligible for the fingerprint showdown, unless they happened to come from a recent case, must have been filtered through round after round of cold cases; what kind of good fingerprint could it be?

Jiang Yuan handed the just-printed document to Zhang Liming: "Based on the partial fingerprint, I've narrowed it down to eight people here. These eight people each have at least six or seven matching feature points; moreover, as Li Dui said, the Level Three feature points, these eight people also have partial matches. After Liu Zhi takes back high-clarity fingerprints, we'll compare again and then be able to confirm whether anyone hit."

Jiang Yuan said, then specifically told Liu Zhuang: "I collected the fingerprint from the victim's outer coat; judging from the defensive wound position, the fingerprint used for comparison possibly belongs to the killer, so be careful with safety! On the other hand, it might just be a related person who left it beforehand. So, among these eight people, even if someone gets hit, when you look for people, you need to pay attention to your methods."

Zhang Liming immediately stepped forward, extended his palm, flipped it left and right: "Pay attention to scale, be courteous, bring more people, stay more alert."

"I understand." Liu Zhuang immediately nodded: "One group of four people, eight groups."

He glanced at the ID numbers of the few people on the printout—from all over the country, south and north; fortunately, the fingerprint showdown had just begun, and his prepared personnel underneath were not lacking.

Li Zeming specifically said: "Among the people you dispatch, those who can take high-clarity fingerprints—you have trained criminal police, or just bring a crime scene or trace inspection person. How high clarity do you want? Above 1000 DPI scanning resolution?"

That last sentence, Li Zeming asked Jiang Yuan. This is also the standard established in 2005 by the U. S. National Institute of Standards and Technology.

Jiang Yuan hummed: "Best to follow 1000; if you can't find anyone, only non-contact fingerprinting is possible, then minimum 500."

"Is 500 okay?"

"500 can identify sweat pore positions on grayscale images." Jiang Yuan said.

The two asked and answered; Liu Zhuang didn't quite understand, but immediately decided: "I'll assign one forensic science person to each group."