In fingerprint identification analysis, fingerprint collection is only the first step.

It is the basis for all subsequent work.

It's like building a building, the foundation is not in place, and the building is not high.

It's like going to some KTV with diversified services to sing, and there is a gap between the 800 yuan service and the 1,000 yuan singing lady.

It's not that the more money you have, the less you wear, on the contrary, the more money you have, the more clothes you may have.

Lu Chuan's groundwork is completed, and the rest is on topic.

Intermediate fingerprint collection skills allow Lu Chuan to be competent for most of the fingerprint collection needs.

Next, it's time for the intermediate fingerprint analysis skills to come into play.

Although he stayed up all night and was very tired, Lu Chuan's spirit was in a relatively high state.

Although the process of collecting fingerprints is very complicated and boring.

However, the more difficult the fingerprint collection, the greater the sense of accomplishment after success.

In front of the computer, Lu Chuan stared at the screen with red eyes.

Lu Chuan still uses the image processing software that comes with the fingerprint comparison system.

The first thing he started with was the fingerprints collected from the frame of the picture that Yang Sen and Lao Bai failed to compare yesterday.

Compared with the speed of Lao Bai and the two of them processing a fingerprint in two or three hours, Lu Chuan's processing speed is much faster.

The magnified fingerprints, like line drawings, are bent and twisted in the lines, and are irregularly distributed on the screen.

The pretreatment that Lu Chuan has to do now is to restore the fingerprints that have been seriously deformed due to force and friction to their normal form.

And look for feature comparison points based on experience.

At this moment, Liu Guodong, Yang Sen and Lao Bai were all watching quietly behind Lu Chuan.

"Last time, I remember Xiao Lu saying that he has studied fingerprint collection, and he is average for fingerprint identification......

But Lao Bai looked at the speed at which Lu Chuan's operating software processed fingerprint images, and it was obviously not like an ordinary appearance.

Liu Guodong also frowned and watched Lu Chuan preprocess his fingerprints.

Among the three, his level is the highest, and Lu Chuan has been studying with him since he went to work.

Including the first few fingerprint identifications, Liu Guodong also told Lu Chuan some skills and methods.

Therefore, Liu Guodong understands Lu Chuan's fingerprint identification level.

He has mastered some skills and has relatively solid theoretical knowledge, but lacks experience and exercise.

But in the past few days, Lu Chuan's operation on the computer, Liu Guodong actually had some feelings that he couldn't understand.

A fingerprint photograph is constantly zooming in and out, and one feature point is constantly marked, and then it is canceled and labeled again.

Liu Guodong was quite dazzled.

Call!

Lu Chuan, who breathed a sigh of relief, finally got a fingerprint, and the intermediate fingerprint identification and analysis skills brought him not only a lot of skills that he had not been exposed to before.

There is also a wealth of experience, and the immediate benefit is that the speed of identification analysis is greatly improved.

"Put it in the system, run aside."

Lu Chuan muttered to himself, and directly entered the fingerprints that had just been processed into the fingerprint comparison system.

Stretching, Lu Chuan got up and was almost scared down.

"Master, why are you here?"

Facing the three big heads, Lu Chuan looked confused.

Ahem.

Liu Guodong coughed dryly: "I just saw you processing fingerprints, let's come over and take a look." ”

"yes, come and have a look."

"We've just come here, too."

Yang Sen and Lao Bai's posture with Liu Guodong is very standard.

"Xiao Lu, you just dealt with the fingerprints extracted from the frame yesterday, right?"

Lao Bai was very impressed by yesterday's fingerprints, and he stared at them for two or three hours, so he recognized at a glance that Lu Chuan was dealing with the one he had fought yesterday.

It's just that the result is obviously because Lao Bai's technology is not good, and the fingerprints are unsatisfactory, which is not pleasant at all.

Lu Chuan nodded and rubbed his eyes: "This fingerprint is more seriously deformed, and there are some scratches, but fortunately, there are not many breakpoints, and it is relatively simple to deal with, and it is easier to get." ”

Simple?

Easy to get?

Lao Bai swallowed his throat, he didn't think this fingerprint was simple and easy to get yesterday.

The pre-processing of deformed fingerprints has always been a difficult problem.

It is a checkpoint to test the strength of the criminal police.

Lao Bai and Yang Sen are at the bottom of the food chain of the criminal police.

It's much stronger than the new college students.,Experienced.,There are a lot of local methods.。

Some fingerprints that are not too badly deformed can be compared successfully.

It is much stronger than the technical staff of the county-level criminal police brigade.

In the eyes of the people below, Lao Bai and Yang Sen are already technical powers that normal criminal police can access, and they are at the ceiling level.

But when I encountered the fingerprints extracted from yesterday's frame, with scratches and serious deformations, there was nothing I could do.

Just like chasing a woman, Lao Bai and Yang Sen have a limited level to deal with.

Liu Guodong's strength is even stronger.

In dealing with some complex fingerprint identification, such as fingerprints with more serious deformation, the probability of success is much higher than that of Lao Bai and Yang Sen.

Among the more than a dozen criminal investigation detachments in the province, they belong to the level of normal technical leaders.

It can meet the needs of on-site investigation and trace inspection of major cases that are generally not too complex.

But compared with the experts of the provincial department, there are many gaps.

Just met the requirements for participating in the fingerprint battle at the provincial level, the kind at the bottom.

And now, Lu Chuan is doing the process of fingerprint identification and analysis, which makes Liu Guodong quite feel like he is watching the fingerprint identification of senior experts from the provincial department.

Know what you're doing, but don't know it entirely.

It's like...... I went in, but it didn't seem to be long enough to go in completely.

If you can describe it in one sentence, it is unclear.

Bite!

Just as he was thinking about it, a characteristic beep came from the computer speakers.

Basically, Liu Guodong, who deals with the fingerprint comparison system every day, is too familiar with this voice.

"Success?"

An expression of surprise flashed across Lao Bai's face and threw himself on the screen.

"Match success!"

The fingerprint comparison system used by the Haizhou Criminal Investigation Detachment was built from the first generation of the system.

Basically, the system is upgraded every year.

Up to now, there are basically three modes of fingerprint comparison in the system.

First, the comparison failed.

Commonly known as the fool mode.

After the fingerprints are preprocessed, the system will compare the features of all fingerprints in the database according to the pre-marked feature points.

This requires low fingerprint identification.

Because only one feature point needs to be determined, as long as this feature point is different from the same feature point of other fingerprints, it can be judged as a failure.

The comparison is complete.

However, there is a problem with this comparison, that is, when preprocessing fingerprints, the selection of feature points should be standardized.

Only by selecting the criteria can the comparison be successful.

If the location is not standard, it will definitely fail.

That's why Lao Bai and Yang Sen kept comparing and failing last night.

When they preprocessed the fingerprint, they did not succeed, and there was a problem with the feature points selected.

The second mode is similarity matching.

This is also the most commonly used identification and analysis method, and the system will match the fingerprints of the database according to the feature points marked by the fingerprint.

Then, according to the similarity of the feature points, a ranking is given.

Of course, this does not mean that the first place is necessarily the successful object.

It also needs to be manually confirmed by the two fingerprints, and if you can find significantly different features, this comparison fails.

The advantage of this model is that the system will give dozens or even hundreds of similar fingerprints.

There is a high probability that there is a target fingerprint here, but it needs to be checked manually.

The last one is the fingerprint comparison method chosen by Lu Chuan.