The small lecture hall of Qinghe Bureau is located on the first floor of the office building.

The potted plants inside are a bit withered, but no one cares.

It, along with other unimportant departments, has its doors wide open, welcoming visitors from all directions. This includes the uninformed masses and police officers from various places who are also uninformed.

However, the utilization rate of the small lecture hall is still very high.

As a virtual department of the bureau, Qinghe Bureau attaches great importance to the organization and reporting of various activities. Otherwise, its existence would be meaningless.

Today's small lecture hall is also filled with quite a few people, and a tall young man is slowly giving a lecture, as if a college student is giving a speech on stage.

However, the atmosphere is quite different.

The young police officer has a gray shoulder patch, indicating that he is a technical police officer. He is wearing a complete police uniform, which looks good. Although he doesn't have the appearance of a popular internet celebrity, he can be considered a refined and sunny young man. Sitting on the podium, he has a serious expression and is at ease. Just by taking a photo, it seems like it can be used for publicity.

Jiang Yuan also wore a pair of plain glasses for this training. He doesn't actually have myopia, but his master said that wearing glasses would be better for him.

The group of police officers sitting in the audience seats, on the other hand, looked nervous and solemn as they stared at the projection screen. The muscles on their cheeks were visibly twitching, and their eyes were wide open, showing great effort.

The first 20 approximate fingerprints matched were listed on the right side of the screen in a vertical column.

The left three-quarters of the screen displayed the fingerprint with the highest similarity value.

"Well, let's take a look at the fingerprints returned in the first round."

Jiang Yuan pushed his unfamiliar glasses frame with one hand and held the mouse with the other hand. He clicked once, enlarging the fingerprint on the left side to full screen.

The fingerprint displayed on the projection screen was also quite clear.

"Well, there is an exclusion point here." Jiang Yuan clicked twice, enlarging the fingerprint again. Then, he drew a small circle on the right side of the fingerprint with his mouse, indicating it to everyone.

For the fingerprints that have already been matched, the standard is not how many matching feature points there are, but whether there are any inconsistent feature points.

This is easy to understand. If two fingerprints are the same, theoretically, all their feature points should be the same.

Therefore, if there is one inconsistent feature point between two fingerprints, it can be determined as "excluded".

In other words, the two fingerprints are not the same, they are not the same fingerprint.

Following this line of thinking, Jiang Yuan excluded two approximate fingerprints in a row.

At this time, Cao Keyang from Qinghe City Bureau, who had already sat in the front row, said, "Teacher Jiang, should we compare the two fingerprints side by side? It's not very clear for everyone to see it like this."

Jiang Yuan reacted quickly and immediately clicked twice, causing the original fingerprint and the matched fingerprint to appear at the same time in the left three-quarters of the screen.

"Sorry, I was thinking that we could do the previous fingerprints faster." Jiang Yuan sincerely said.

Cao Keyang inexplicably felt a touch of sourness in his heart and hurriedly said, "It's okay, it's not your fault. It's just that, since we are giving a lecture, it is better to speak slower and clearer."

"Yes, yes, I will pay attention." Jiang Yuan nodded and continued, "Let's exclude the first two fingerprints again."

Then, Jiang Yuan drew a circle with the same action on the right side.

The difference was that he then drew a circle on the left side.

As a result, the audience finally let out a coherent "Oh" sound.

Seeing this, Jiang Yuan continued to work diligently, circling the second and third fingerprints, and then excluding them.

The "Oh" sounds from the audience gradually decreased.

Technicians whose fingerprint level was lower than LV1 began to feel a sourness in their hearts, a sour and indescribable feeling.

They finally understood that Jiang Yuan had memorized the entire original difficult fingerprint.

So, just now, he used pure memory to exclude them.

There was no need for comparison. With the original pattern in his mind, excluding or comparing was naturally very fast.

This was actually nothing.

If they had started preparing for the lecture a few days ago, everyone would be able to remember parts of the fingerprint... the parts that mattered.

But who would do that?

No one expected such detailed fingerprints to be remembered.

Even the fingerprints themselves would find it annoying.

It was only the forensic experts who, after focusing on a difficult fingerprint for a long time, would gradually remember its characteristics. But...

While some people were lost in their thoughts, Jiang Yuan excluded three more approximate fingerprints.

Then, Jiang Yuan said, "At this point, it is generally recommended to finish looking at all 20 fingerprints. But we won't do that today because the similarity of the fingerprints that have come out is getting lower and lower, indicating that the probability of finding a match in the later ones is already very low..."

Cao Keyang was dumbfounded.

The crowd was dumbfounded.

Why did this feel so familiar?

It was like when they were still in school, they lowered their heads to pick up a pencil, and when they raised their heads, they couldn't understand what the teacher was saying anymore.

Even the last moment's words were the same: I won't write about the following steps because they are relatively simple, so let's skip them. But the conclusion that can be drawn from this is...

Jiang Yuan had no intention of pausing.

After the first wave of fingerprint elimination, Jiang Yuan pulled out the original fingerprints again and said, "Now let's mark the second round of feature points."

Dazzling,

Dazzling and captivating,

Out of sight, out of mind,

Being annoyed is useless.After the operation, Jiang Yuan re-marked the thirteen reference points.

Jiang Yuan said, "The positions we just marked are relatively ordinary reference points. If there is no match, it means that the previous forensic work was done well and the suspect did not leave clear fingerprints for us to match. It's okay, let's try again."

Similar to the previous steps, Jiang Yuan compared the marked fingerprints with the fingerprint database.

After a while, the database returned data with 20 fingerprints.

"Do we still need to compare left and right?" Jiang Yuan asked Cao Keyang politely this time.

Cao Keyang nodded obediently and focused on the projector.

This time, he felt prepared.

Two fingerprints were displayed on the left side of the projector, about three-quarters of the way down.

Jiang Yuan moved the mouse lightly and circled one on the left and one on the right, saying, "Excluded, right? Similar to the previous ones."

"The second one is also excluded."

"Same here."

"For the ones below, do we need to circle them one by one?"

While speaking, Jiang Yuan quickly took photos of the fingerprints.

He pressed the spacebar on the keyboard, and a new fingerprint appeared on the screen, replacing the old one.

Since Jiang Yuan didn't need to circle anymore, he just took a quick look, said "no," and pressed the spacebar again to replace it with a new fingerprint.

Cao Keyang initially stared at the screen, but soon fell back into the same state as before:

Eyes

Chaotic

Eyes

Annoyed

For a moment, Cao Keyang almost thought he was scrolling through short videos.

The screen was filled with internet celebrities, and they all looked quite similar.

Take a look, swipe away.

Look at another one, swipe away.

In a daze, half an hour had passed.

At this time, Jiang Yuan had re-marked the features of the fourth wave and said, "Actually, the features we just marked were not necessary. It was just to show everyone."

"In the future, when we become more proficient, we can skip the marking process we just did because the features we marked earlier are repeated from the previous two times. If it's just for experimentation, this method is not efficient."

"The more efficient way is to define a small area and mark as many features as possible. This will also improve the accuracy of the feedback fingerprints. Of course, it will be a bit more difficult."

"Or we can stick to the previous method..."

As Jiang Yuan spoke, the sound of tapping the spacebar echoed in the training room.

Not only Cao Keyang, but most of the technicians in the room were numb.

Jiang Yuan was too fast.

They couldn't keep up.

However, they didn't consider that if Jiang Yuan followed their speed and explained while doing the fingerprints, it would take several days to handle a difficult fingerprint.

The training session only lasted for two 4-hour sessions.

At this moment, a senior forensic examiner cleared his throat, indicating that he wanted to speak.

Everyone held their breath, waiting for this brave brother to speak up.

After all, this was a training session in the disciplinary forces. If they upset the teacher, they could easily face consequences.

The sound of tapping suddenly stopped.

For about half a minute, Jiang Yuan didn't speak or move.

The training room was so quiet that Cao Keyang, who had almost given up, couldn't help but look up at the projection screen.

On the screen were still two fingerprints.

The left one was the original difficult fingerprint, like a girl wearing tight-fitting pants, almost revealing everything but not quite.

The right one was a fingerprint from the database, ordinary-looking, like a professional woman in a suit, with sharp eyes and precise movements, without any flaws...

"It's a match, right?" Jiang Yuan added behind, as if it was part of the lecture.

Cao Keyang was dumbfounded. What did it mean by a match?

He looked at the original fingerprint on the left and then at the fingerprint from the database on the right.

They seemed quite similar.

Almost identical.

No flaws.

Find the original at bit.ly/3iBfjkV.

Unable to exclude.

So... does that mean they are the same person?

In the end, the girl in tight-fitting pants and the professional woman were the same?

Cao Keyang was stunned.

Not only Cao Keyang, but half of the police officers present for training were in a daze.

At this point, Jiang Yuan began to skillfully write the identification report for "same person determination" and requested a review.

In the room with over forty people, only Jiang Yuan was filling out the form.

Everyone understood this part.

"Just wait a moment for the review on this side. I'll make a call to the jurisdiction here." Jiang Yuan said, then turned to the students and said, "Sorry for the delay, but since we have identified the suspect, it's polite to make a phone call."

"It's okay, it's okay." A group of police officers anxiously waved their hands.

Jiang Yuan switched back to the case details and found the contact information for the police station in the jurisdiction. He smiled and said, "It's in Miaohe County. I had a phone call with them before, just a moment."

When Jiang Yuan participated in the fingerprint battle across the province, he matched a fingerprint from an unsolved case in Miaohe County, so he had the phone number of the captain of the Miaohe County Criminal Police Brigade.

Jiang Yuan made a call, and soon, the cheerful voice of the captain of the Miaohe County Criminal Police Brigade came through, "Forensic Jiang, why do you have time to call me? Is it good news?""I just matched a fingerprint from an ordinary case, a robbery that happened over six years ago... Yes, I'll send you the specific information over the internal network... Yes, yes, oh... The review has passed... You're welcome, you're welcome."

Jiang Yuan was sitting at the lectern, the sound was clear, and the conversation from the two people's phones almost entirely reached the ears of everyone present.

The technicians in the room looked dazed.

The temper of the captain of the criminal police team in Miao River County was so good?

Could such a good-tempered person be the captain of the criminal police team?

Also, what just happened?

In the eerie silence, Jiang Yuan completed the step of sending information over the internal network.

"Alright, the review has also passed, so, this robbery cold case from six years ago now has a new key clue. Next, it depends on whether Miao River County can locate and arrest the suspect. For us, the fingerprint comparison work for this case is considered complete."

Jiang Yuan closed the few pages he had just opened, completing the final tidying up.

"Let's find another typical fingerprint and repeat the method we just used to see if it works." Jiang Yuan started looking for fingerprints again.

The guy who was just clearing his throat finally couldn't help it, he stood up, but what he wanted to say completely changed: "Just now, were we working on a real case?"

"Yes." Jiang Yuan replied, "That's why I said it's a practical class. So... can you get used to the content I teach and my teaching style?"

"Yes, yes, yes, but, no, we... no, you... no, did you just solve a robbery case?" The guy who was clearing his throat seemed unable to accept this.

Soon, the small lecture hall was buzzing with voices.

Someone even quietly sent a message: Brother, come and see the god.

(End of this chapter)