Before the era of photography, and then digital technology, images were taken by applying them to paper from prints on stones, wood and metal. A good art history education includes learning and recognizing various printing techniques. This is an extensive area of human knowledge that you can devote your whole life to studying, this article will introduce you to the basics of creating letterpress prints from a wooden cliche, intaglio printing from stone (metal), flat printing (lithography), in the future you can improve your knowledge.
Pros and cons of fingerprint scanner
Like any other new technology on a smartphone, a fingerprint sensor has its advantages and disadvantages. The user can immediately note three main positive points:
- new opportunities,
Indeed, using a scanner is easy. In addition, you do not need to invent and keep passwords, codes, and other keys in your memory. Unlock time is noticeably shorter. One touch - and the device can be used.
Having received a new function, the user discovers new opportunities.
In addition to unlocking the smartphone, the scanner can be used to authorize on sites or confirm purchases in online stores.
Suffice it to recall that the Samsung Pay contactless payment system uses this particular technology.
On many models of smartphones, the shooting function when the scanner is touched is turned on by default, which is very convenient. The fingerprint sensor in Android is often integrated into the central button, and the photo can be taken without unlocking. The alarm also turns off.
As for security, not everything is clear here, although fingerprint identification is considered one of the most reliable. Using a fingerprint sensor has its drawbacks. The fact is that fingerprint images are stored on the device, and if not encrypted, access to them is poorly protected. Once falling into the wrong hands, the fingerprint will become a constant pass for attackers, since changing it as a password does not work. In addition, the optical scanners used on smartphones are easily dirty and scratched.
How the fingerprint scanner works
Let's see how the fingerprint scanner works on Android. Regardless of the type of sensor used, it receives the actual image of papillary patterns at the fingertips, compares them with the sample, clogged in memory, and unlocks.
So far, the most popular is the optical sensor, which works like a camera. When a finger is applied, a special microcircuit with a matrix with photodiodes and an autonomous light source copies a graphic image of the surface of the finger.
Light falls on the photodiodes, an electric charge is created, and the potential difference forms a picture. The intensity of a pixel’s luminescence depends on the amount of incoming light, and their combination creates an image with a resolution of 1200 dpi or more. Before comparing with the “original”, the scanner will check the image for quality. If the clarity or brightness is unsatisfactory, the device will change the shutter speed and try to repeat the process, and then analyze the image with special software.
The scanning program used a complex algorithm. First, the type of pattern is determined, then the location of the lines, their endings, gaps, bifurcations, etc. By minutes, the owner is identified. Each image is divided into fragments of 9 by 9 pixels in size, which are compared with identical blocks in the device’s memory. The lines of the pattern are not individually analyzed; patterns (angles, turns) are found, according to which the similarity is established.
In addition to optical, semiconductor (capacitive) and ultrasound scanners are used, which are distinguished by increased complexity and reliability. The first ones work like touch displays: a finger conducts a current that changes the charge of microscopic capacitors depending on the pressing force, which, in turn, depends on the configuration of the skin patterns. In the second case, unlocking the screen with a fingerprint for Android involves the process of scanning the fingertip with ultrasound. Such sensors work faster and do not depend on the cleanliness of the contact pad or skin damage, but so far there are very few smartphones with them.
Setting up a scanner on the phone
The sensor turns on almost the same on most Android devices. To do this, you must:
- Enter settings.
- Go to the "Security" section, then to "Screen lock". On some models, the function switch is located in Advanced Settings.
- Find something like Fingerprint, Fingerprint Management, Application Lock, Lock Screen and Fingerprint, Security and Fingerprint, Fingerprint Scanner Gestures, or Lock and Fingerprint.
- Set the PIN code that will be used in case of failure.
- Select “Fingerprint No. 1” (if you need several, then you can click on “Add Fingerprint”).
- Touch the scanner several times with one finger until a confirmation of the readiness or unlocking of the screen appears (the type of message also depends on the model).
On some devices, the fingerprint manager function is implemented, by entering into which you can set several samples.
As a recommendation, you can advise slightly changing the position of the finger on the scanner site so that it has the ability to cover the maximum area. Then the operation errors will be less. And yet - do not use your thumb and forefinger. Attackers can easily find their fingerprints, but the little finger and nameless fingerprints on objects almost do not leave. If the owner is right-handed, it is better to use a fingerprint of the left hand and vice versa.
Set up a fingerprint to confirm payments on Google Play
Fingerprint confirmation of payments is already becoming a trend. To connect a function, you need:
- Sign in to the Google Play Store.
- Open settings.
- Find the item "Authentication by fingerprint" and put a checkmark next to it.
- Enable mandatory authentication for purchases.
Such authentication is more convenient and safer than traditional methods of payment confirmation. But still it is not recommended to use a scanner for authorization in payment services and banking applications.
How to install a fingerprint scanner
Although fingerprint scanners are already quite common on new models, by far not all users have a smartphone with support for the Fingerprint API (you need Android 6.0 and higher). If it is not on the device “out of the box” and an OS upgrade is not possible, and you really want to get a chip, special software is used, which is easy to find on Google Play. Moreover, you can use such a scanner not only to unlock, but also to solve other problems on the device with any version of Android.
Fingerprint recognition utilities
You can find a suitable fingerprint application on Android in the official store or on third-party resources on the network. Such programs have become very popular, so there are plenty of offers. Of course, not all utilities work correctly, so we present a list of the best.
This utility allows you to block access to any single application, but can only be used on Samsung devices. After starting, you can scroll through the list of programs installed on the device and mark the required ones. At the next opening, they will be asked to provide a fingerprint.
A very convenient solution if you need to temporarily transfer the gadget into the wrong hands. It has a well-functioning energy saving mode, and the sensor always works in any conditions. It is also possible to disable the lock for a while using the program.
Dactyl allows you to use the scanner as a button on the camera. If you need to take a selfie, but there are no physical buttons on the smartphone, it’s easier to use the button of this application. If you want to take a picture with the main camera, this is the only alternative.
Fingerprint quick action
This multifunctional program has no analogues. The application makes it possible to use swipe to unlock or raise the notification curtain.
This is an indispensable feature when the screen size is too large. In the settings there are options for minimizing all applications, quick transition to the desktop and others.
Privacy Ace AppLock
This program also allows you to put lock on individual applications. After installation, it appears in the menu in the form of an alarm icon, without a name - for disguise. The weight of the utility is small, as is the charge consumption. In addition, she photographs a potential cracker.
Hexlock allows you to set a password not on the entire device, but on separate applications, even installed from third-party sources. The program includes six configuration profiles with different lists of blocked applications for different locations. The setting involves the selection of Wi-Fi networks, when connected to which this or that profile will work. This is a really beautiful and powerful blocker with scanner support.
This utility can also lock a separate application. Unlike most analogs, it uses a recognition method that is not based on polling.
Using the utility involves the following procedure:
- First, the program needs to be downloaded and installed. It is free and available on Google Play.
- At the first login, the utility offers to set a PIN-code or graphic password, and then add an email.
- A list of all programs installed on the device, as well as non / blocked ones, will appear. Next to each is a switch in the form of a slider, by sliding which you can enable or disable the lock.
- Enter the application settings and enable the fingerprint scanner.
In the settings, you can set the time to restart (automatic) after unlocking. There is also a “Hide photo” tab, which opens access to the store to download the Keepsafe photosafe program. It allows you to do something that the above fingerprint program on Android cannot do - to protect folders with photos and videos. But there is no scanner in it.
The program solves the issue of protecting a photo album from prying eyes. In addition to being a functional gallery in itself, it has a folder that can only be accessed through a scanner.
The most popular online password manager is now offered for free. The utility is able to synchronize account access passwords between devices and allows you to reliably protect access to the repository.
LastPass stores passwords locally, in the telephone database, and even in the cloud. She sees passwords that are not visible to other managers, including AJAX forms. The program is able to import and export data from almost all known storage systems, fill out forms, automate input, generate secure passwords and much more.
This is a wonderful personal diary with a convenient and functional interface, moreover, it is reliably protected by a lock that can only be removed with a scanner. With it, you can immediately send ready-made recordings to the Google Drive cloud, where no one will read them either.
Solo Photo is an analogue of Focus Gallery. The application allows you to enable the scanner to unlock existing folders in the gallery. It is enough to indicate those that need to be protected. To enter them, you have to put your finger on the scanner.
Other screen lock methods
In addition to fingerprint sensors, some manufacturers are trying to introduce other types of biometric identification. Voice recognition and iris have certain prospects. There are technologies and examples of use, but so far these functions have not been implemented on smartphones. The main methods of blocking are still a PIN, password and pattern.