After lunch, more than a dozen people did not go back to rest, and the atmosphere in the fingerprint battle conference room was a bit depressing.
It's like before a storm comes, heavy clouds are pressing above your head, there is no wind, no rain, just breathless depression.
What Wang Hui said just now made everyone feel a little heavy.
Lu Chuan sighed and forced himself to focus on the computer screen.
Fortunately, the case was solved.
The child's spirit in heaven will eventually rest in peace.
The third case.
After the battle, there were more than 80 murder cases in the fingerprint database. Lu Chuan excluded a few from Haizhou City. He had compared the cases last month and found no cases with the target fingerprint in the system, so he randomly selected one.
This time the fingerprints are a little blurry compared to the previous two.
There is only a narrow strip less than half a centimeter wide.
The ridges were twisted and squeezed together, and the entire fingerprint seemed to be squashed by the crack of the door.
Fortunately, although the fingerprint lines are squeezed together, they are not very blurry.
This time, Lu Chuan did not use layered image processing. Instead, he needed to use stretching and deformation to widen the narrow fingerprints and turn them into normal fingerprints.
Here, it is difficult to use mathematical transformation methods.
Because the fingerprint lines are relatively clear and are just squeezed together, Lu Chuan's advanced fingerprint identification and analysis skills have special analysis methods for such fingerprints.
That is to stretch according to the regular characteristics of fingerprints.
Although everyone's fingerprints are unique, there are still certain rules for the growth and development of fingerprints for people of different ages and genders.
The length of the ridges and the width of the intervals all have certain rules to follow in terms of probability.
What Lu Chuan needs to do now is to roughly judge the width pattern between fingerprint ridges based on the length of the fingerprint and the width of the ridges, so as to stretch the fingerprint. .
This is also what other experts who have studied this fingerprint have done.
However, compared to technical pre-processing fingerprints, this fingerprint processing method is more demanding of experience.
Only by experiencing enough fingerprints can we subconsciously make appropriate and accurate judgments.
Although the number of fingerprints that Lu Chuan identified and analyzed in reality was not large, the experience rewarded in the system skills was quite a lot.
Dragging the fingerprint into the PS image processing interface, Lu Chuan enlarged the fingerprint, starting from the center and pulling outwards, gradually enlarging it, and adjusting the width of the ridge.
An important point here is that you must start zooming in from the center point of the fingerprint, although this is the place where fingerprints are most densely stacked and it is difficult to start.
But that’s because there are too many fingerprint ridges, and the overlapping visual perception creates a false impression.
In fact, since the closer the fingerprints are stacked to the middle, the smaller the space that can be compressed, the distance between the fingerprint ridges in the middle is closer to the width of the suspect's real fingerprints compared to the outer edges.
The adjustment range will also be very small. In this case, by gradually stretching from the inside to the outside, the most accurate approach to the real fingerprint can be achieved.
But if you start from the periphery, although it feels much easier, in fact after cleaning a few ridges, you will find that the fingerprint ridges that have been cleaned on the periphery will not automatically extend, so they will be stacked together again.
Therefore, it is necessary to clean up the peripheral ridges in turn.
To a certain extent, because it cannot be put in place directly at once, it will also cause stacking, and then it is cleaned repeatedly, and then stacked again...
It goes on and on, a vicious cycle.
And since each extension is done by the appraiser based on experience, even an expert-level fingerprint appraiser cannot guarantee that his experience will be accurate every time.
Deviations will naturally occur after a few more attempts. At that time, if you want to successfully identify and analyze, the difficulty will increase exponentially.
In the end, just like now, three or five years later, the fingerprints still cannot match the suspect.
Of course, Lu Chuan stretched the ridge from the inside out, and could only stretch the middle one.
parts, the outer ridges will not automatically stretch outward.
But what Lu Chuan wanted to do was not to stretch the entire fingerprint. Only a small part in the middle, even one-tenth the size, was enough for identification.
Although such a small area may not be able to mark enough feature points to become judicial evidence, as long as there is a direction, the remaining criminal police will be on site.
As long as the target can be locked based on fingerprints, the rest is just a matter of continuing to dig.
For example, in the case of Chen Xiaosong's murder, his stepfather's fingerprints were locked. In fact, during the interrogation, it was discovered that his mother was also an accomplice.
Working as a police officer to solve crimes is never a solo effort, nor is it a place to show off your personal heroism.
Sincere cooperation and united fighting are the way to go.
At the same time, Tianzhou City Criminal Investigation Detachment.
Detachment leader Wang Chuanmin personally took charge. After receiving a call from Li Donglin of the Provincial Department of Criminal Investigation No. 2, he immediately organized an action team to prepare for the arrest.
"The other party is suspected to be the murderer of the taxi driver's serial murder case twelve years ago!"
Before the action, Wang Chuanmin held a mobilization meeting in the conference room.
"According to the information we have obtained in the past, the other party has extremely strong reconnaissance and counter-reconnaissance capabilities. We must be cautious during the arrest process."
"Everyone, body armor and firearms are ready!"
"Set off!"
No. 28 Minzhu Road, Sainty Jinmao Building.
"The suspect is on the 28th floor. He is an executive of an economic and trade company. We just confirmed through cleaning that he is inside."
Zhao Ming, the leader of the action team, has confirmed the other party's situation.
"action!"
"yes!"
Thirteen minutes later.
From the elevator, Zhao Ming and others escorted Xu Wenbing, who was wearing a hood, out of the elevator.
The arrest process did not go smoothly. When Xu Wenbing saw the police suddenly breaking into the office, he resisted violently.
This Xu Wenbing not only has a strong sense of reconnaissance and counter-reconnaissance, but he is also a master of fighting.
The four heavily armed criminal policemen who entered Xu Wenbing's office together were almost robbed of their firearms by the other party.
If it weren't for Zhao Ming hugging the opponent's midfielder at the critical moment, holding back two elbow blows and not letting go.
It may cause irreparable consequences.
Now, Zhao Ming still felt as if his back had been hit by a car, grinning in pain.
"Are you okay?"
Zhao Ming shook his head: "It's okay, it just hurts so much. I don't know how this kid can practice his skills so hard!"
"Strong? This guy was our city's free sparring champion twenty years ago, and he ran marathons for nearly ten years."
Zhao Ming shook his head, this person is indeed difficult to catch.
"By the way, Captain, I heard that the fingerprint was found by Lu Chuan from the Haizhou Criminal Investigation Detachment?"
Lu Chuan is quite famous in the Tianzhou City Criminal Investigation Detachment.
Wang Chuanmin smiled: "Not only that, he also won a case in Qianzhou City this morning. He won two murder cases in one morning!"
Although the other party was difficult to deal with, he was eventually arrested. While the two were talking, the suspect was escorted into the car.
The interrogation began immediately.
At 4:30 in the afternoon, just as the Tianzhou City Criminal Investigation Detachment operation had just ended, Lu Chuan took a long stretch in the fingerprint battle conference room.
After more than three hours, I finally got this fingerprint!
