What is the principle of face recognition

Now the brush face is becoming more and more common.
I need to sign in with a pen before going to work
Now you may only need to scan the brush machine to complete the attendance.
So what is the principle of face recognition?
In fact,
the machine is not good at identifying images.
For example,
a middle-aged uncle in the robot is also just a string of zero sum data.
It doesn't understand the meaning of the picture.
So we want machines to learn to recognize images,
so we need to write program algorithms for them.
When we describe a person's appearance
Most of the words are used in words like this
For example, willow garlic cherry mouth eye face,
So appearance depends largely on the shape of human head and facial features.
The earliest way of face recognition is to adopt such a method.
First, the machine will identify the location of the connection in the image.
And then depict the outline of the five senses on the face.
Get the shape and location information of the facial features on the face.
For example,
the distance between two eyes,
the angle of the nose, the angle of the mouth,
the angle in horizontal direction and so on.
So we can judge whether this face is a known face through these data.
Or find out which face is directly in the database.
But the feature data obtained in this way are relatively small
The result is not particularly accurate,
Now we have more advanced algorithms to deal with and compare images,
for example,
some algorithms are no longer a line drawing from the image,
but a direct contrast of the two face images,
which is equivalent to getting more feature information in a more comprehensive and detailed way.
Now the machine is even more than a person in the correct rate of human face recognition.
Class, but as more and more fields,
especially the financial industry,
are using face recognition technology,
there is a problem that may have unlawfully stolen property from the account of other people's photos.
One solution is to let the operator make a few expressions on the landing so that it can be judged not A static picture, but even if such an unlawful element can still simulate these movements by taking video or modeling, t
he face recognition device at a higher level of security now adds some special equipment to judge whether they are identifying a living person,
for example.
It can be equipped with a 3D sensor infrared camera and other devices to perceive whether it is a cold plane before the camera or a three-dimensional face with a temperature,
of course, the face recognition technology is not perfect enough for the unlawless elements to come up with new tricks to attack. I
f you cut yourself up,
you may be in the near future to prove that you are you,
so you don't need to provide certificates or enter the password at all,
just brush your face.