Comparison TP-LINK Tapo D230S1 vs Xiaomi Smart Doorbell 3

— Street (universal). Call panels that can be used outdoors. Even in a fairly mild climate, "street" devices are constantly exposed to various adverse effects: precipitation, temperature changes, ultraviolet radiation; in addition, they can be a very attractive target for hooligans and vandals. All this requires the use of durable and sustainable materials. At the same time, nothing prevents the installation of such panels in the premises (hence the name "universal").

— Premises. Call panels designed for installation inside buildings. Such placement assumes quite favorable conditions (lack of moisture, almost constant temperature, etc.), as well as a minimal risk of vandalism. Therefore, "internal" devices do not have such a margin of safety and reliability as external ones; this has a positive effect on the cost, but does not allow the use of outdoor panels of this type outdoors.

A method for connecting the calling panel to an intercom or other similar device.

All modern connection types can be divided into three main categories: wired analog(2, 3 or 4 wires), wired digital(network - LAN) and wireless(Wi-Fi). Moreover, the last two formats can be combined in one device. Here is a more detailed description of each of these options:

— 2-wire. The simplest type of wired analog connection; used in select low-cost audio panels (see "Type").

— 3-wire. A very rare option: in simple analog devices, manufacturers often provide 2 wires, and in advanced ones - 4.

— 4-wire. The most functional and, as a result, the most popular type of analog wired connection. Suitable even for high-end video panels, although in fact it is found in all categories of devices - from budget to high-end.

— RJ-45. Connection via an RJ-45 connector via an Ethernet network cable (“twisted pair”). This option is convenient because the calling panel can be connected to a local computer network, which provides several advantages. Firstly, the ability to access the panel can be configured on any computer or gadget within the network. Secondly, many similar models can work without intercoms and other special equipment - through an application on a computer/gadget. Thirdly, laying a network cable from the panel to the router/switch i...s often simpler than organizing an analog connection (for example, 4 wires - see above). Fourthly, the number of panels and other special equipment within the local area can be almost any - it is quite possible to combine, for example, all the calling panels of an apartment building or a large office center into one network. And if you wish, you can even set up access to the calling panel via the Internet, which will make it possible to communicate with visitors and control access to the premises, even when you are not on site.

- Wi-Fi. Connection via Wi-Fi wireless standard. This option provides almost all the same capabilities as the RJ-45 described above, but has certain differences. The most noticeable of them is the absence of a wire, which greatly simplifies installation and connection. At the same time, even relatively limited Wi-Fi devices have the power to operate reliably at a distance of a couple of tens of meters or through 1 - 2 medium-thick walls. The second nuance is the possibility of direct communication with a smartphone, tablet, etc., without using computer networks; This possibility should be clarified separately, but it is in this format, for example, that video calls work (see “Type”).

— RJ-45 / Wi-Fi. Supports the two connection methods described above at once. Such panels turn out to be as universal as possible, however, in practice, the ability to freely choose between LAN and Wi-Fi is extremely rarely required, and it significantly affects the cost. Therefore, this option was not particularly widespread.

— Motion detection. A sensor that allows the calling panel with a camera to respond to movement in the camera’s field of view. The specific reaction method may be different, depending on the model and settings of the entire system: turning on recording or broadcasting to an external device, sending a notification to the customer, sending a signal to the alarm output (see below), etc.

- Mobile app. This feature means that you can work with the calling panel via a smartphone or tablet with a special application installed on it. Such applications are usually released immediately for both of the most popular mobile operating systems today - Android and iOS; however, it would not hurt to clarify this point separately. In any case, control from a mobile device can have very extensive functionality (including even the ability to work via the Internet, in some models); and interacting with the panel through a gadget that you can always keep with you is definitely more convenient than every time going to the intercom or other stationary equipment.

— Face recognition. The facial recognition function is one of the types of biometric access systems. It is based on a digital camera, often complemented by a built-in backlight for identifying faces in the dark. Initially, such devices were not very accurate: they could be confused by changes in facial hair or makeup,...the appearance or disappearance of glasses, and some models could be deceived using photography. With rare exceptions, facial recognition today uses advanced algorithms and high-end cameras with 3D scanners that read a three-dimensional model of the face. The device stores the customer library in its memory. The function is found in flagship calling panels.

— SIP protocol. The device supports the SIP protocol. This is a standard originally created for Internet telephony - the transmission of information (audio, video, special data) over telephone networks in digital format using the IP protocol (the same one on which the Internet is built). Internet telephony is quite popular nowadays, especially in business: it allows you to establish effective interaction between individual departments of a company, even tech located in different countries. Accordingly, if the building already uses equipment for Internet telephony, then SIP support can significantly facilitate the integration of the calling panel into the overall security system.

— Reading contactless keys. The presence in the design of the intercom calling panel of a module for reading data from contactless keys. They can be in the form of smart cards, key fobs or other devices that contain a microchip with a unique identifier. When the customer brings the key to the reader, the system identifies it, checks it against the database and allows access if there is a match. Note that the intercom calling panel can record not only the response time, but also the identifiers themselves - this provides advanced capabilities for access control and visitor registration.

— Alarm input/output. As a rule, calling panels with this function are equipped with both inputs and outputs; the number of both may be more than one. In general, these connectors are used to transmit control signals between different ones within a security system; they allow you to build a very advanced system and provide additional capabilities for managing its functions. At the same time, we note that the alarm input or output is not necessarily responsible for triggering the alarm - it all depends on the specific settings. For example, a signal from such an input can serve as a command to turn on the “night” IR illumination or start recording video from surveillance cameras.

— Display. Its own screen, installed directly on the calling panel, allows you to display various additional information useful for the visitor. The specific functionality of such a screen can be different - from a simple indicator that can show only numbers (for example, the number of a called apartment or office) to a full-color display suitable for two-way video communication. However, in any case, this feature increases the convenience and clarity of using the calling panel.

— Night shooting (IR illumination). The presence of an infrared illumination function in the camera video panel (see “Type”), which allows you to obtain a visible image in the dark and even in complete darkness. IR illumination is not visible to the human eye, but is well perceived by the sensors of modern digital cameras. True, the image in this mode can only be black and white, but in most cases this is not any significant drawback.

— LED backlight. The camera video panel (see “Type”) has LED backlighting. Like the infrared illumination described above, this backlight is designed to work in the dark; however, it provides light that is visible to the human eye. The latter, on the one hand, allows the camera to produce a relatively natural color image, on the other hand, it can create inconvenience for the guest due to the bright light in the eyes.

— Illuminated buttons. The design of the calling panel includes backlit buttons. The function allows you to see the keyboard normally even in low light conditions - in the evening, at night, in cloudy weather, when placing the panel in a dark place, etc. Note that the backlight usually covers other significant elements of the panel - for example, the location of the sensor for a smart card or key.

A card reader is a device for working with removable memory cards. Such media are used to record data, which allows you to save events occurring in front of the calling panel at the right time.

Type of matrix installed in the camera of the video panel (see "Type").

— CMOS. She is CMOP. Relatively inexpensive matrices, which, nevertheless, provide good image processing speed with low power consumption, and also take up little space (which is very important for miniature cameras). Their main disadvantage is the increased tendency to the appearance of noise in the image, which is why the quality of this image is somewhat inferior to CMOS CCD.

— CCD. The Russian equivalent of the name is "PZS". Such sensors are somewhat more expensive than CMOS, due to the complexity of the design, and their size is somewhat larger. At the same time, they have more uniform characteristics and are not as prone to heat during operation, which reduces noise and has a positive effect on image quality — especially with a small amount of light.

Diagonal size of the surveillance camera matrix. This parameter is traditionally indicated in inches and fractions of an inch.

With the same type (see above) and the number of megapixels (see below), larger sensors are considered more advanced. This is due to the fact that a large sensor size means a larger area of each individual pixel — and this, in turn, increases the amount of light falling on each pixel, has a positive effect on light sensitivity and reduces noise. Large sensors are especially important for working in low light conditions, including with IR illumination (see "Design and capabilities"). However, for calling panels, matrices are mainly limited to 1/4" and 1/3" sizes. Other options are much less common.

The number of megapixels in the camera sensor, in other words, its resolution. A megapixel is one million light-sensitive dots (pixels) that make up an image; the resolution of modern matrices is very high, so it is more convenient to use just this method of designation. However, for call panels, the values are 1 MP, 1.3 MP and 2 MP. More advanced options are extremely rare.

The higher the resolution of the matrix, the higher the video resolution can be (see below), the more detailed the image can be provided by the door panel camera. At the same time, note that as the number of megapixels increases (without changing the size of the matrix), the size of each individual pixel decreases, which increases the likelihood of noise and deterioration in the overall image quality. Therefore, high resolution in itself is not necessarily a sign of high quality — a lot depends on other things, for example, on the size of the matrix (see above).

The maximum video resolution that the call panel camera can provide.

The higher the resolution of the video, the more details you can see on it, the less details will be blurry. On the other hand, high resolution means large volumes of video materials, which, accordingly, requires fast communication channels, and this indicator significantly affects the cost of the device.

Video compression format (codec) used by the door panel camera.

In practice, this information is important mainly for assessing compatibility with other special equipment, as well as when viewing captured video on household media players. This point is not important for interaction with a computer: most modern operating systems have extensive sets of built-in codecs, and if necessary, additional codecs can be installed separately. However, different video compression formats also have some specific features, here they are:

- H.263. The oldest of the codecs widely used in digital cameras of calling panels. It was created back in the mid-1990s for efficient video transmission over low-bandwidth channels; nowadays it is considered obsolete and is found extremely rarely in calling panels, and exclusively as an addition to the more advanced H.264 (see below).

- H.264. A codec widely used in modern video equipment, including for transmitting high-definition video. It provides a good compression ratio while maintaining quality, and is not particularly demanding on computing power, which is why it is extremely popular in our time.

- H.265. The newest and most advanced of the formats found in calling panels. It provides even higher efficiency than H.264, supports resolutions up to 8K, but has quite serious hardware requirements. As a result, support for this standard is...rarely found in calling panels.