Processor
Model of the processor used in the dashcam
The term "video chip" is used mainly for devices with classic capabilities, "processor" — for advanced models with an abundance of non-standard functions. However, anyway, we are talking about the same component — the main computing unit, the characteristics of which directly affect the capabilities of the recorder as a whole. Knowing the model of the processor, you can find detailed data on it and evaluate how satisfied you are with a device based on such electronics. Of the most advanced modern chips, one can name, in particular,
Ambarella A7L,
Ambarella A12,
Novatek NTK96655,
Novatek NTK96660 and
HiSilicon Hi3516.
VGA (480p)
The maximum resolution and frame rate of video recorded by the recorder in the
VGA standard (480p).
The 480p standard covers several resolutions with 480 vertical pixels; among DVRs there are options 640x480, 720x480 and 848x480. In general, all these resolutions are considered rather low; they are used as regular ones only in low-cost registrars. However, the ability to shoot at 480p can be provided in a more advanced device — for example, to save space on the drive.
As for the frame rate, the higher it is, the smoother and less blurry the video will be, the better the details on moving objects will be visible, and also the more space the footage will take up. Specifically, for the human eye, a speed of 24 to 60 fps is considered quite sufficient, however, among the registrars there are models that can shoot video at 120 or even 240 frames per second in 480p resolution. This shooting speed will be useful for slow-motion or frame-by-frame viewing of footage: it allows you to very clearly capture even fast-moving objects, which is important when analyzing ambiguous situations.
HD (720)
The maximum resolution and frame rate of video recorded by the recorder in the
HD (720p) standard.
The classic resolution for this standard is 1280x720, but there are other options in DVRs — in particular, 1280x960 (4:3 aspect ratio). Anyway, HD is not outstanding, but quite a decent indicator that allows you to get a video with good detail (for example, it is usually quite possible to make out numbers on cars in close proximity to a car on it).
As for the frame rate, the
higher it is, the smoother and less blurry the video will be, the better the details on moving objects will be visible, and also the more space the footage will take up. It is worth noting here that in some inexpensive models, shooting in HD at very low speeds — 15 – 20 fps is used to reduce the cost. Such a shooting speed allows you to watch video more or less normally, but for a normal display of moving objects, a higher frame rate is still desirable — at least 25 frames / sec. It is also worth saying that, in general, for a comfortable perception by a person, a speed of 24 to 60 frames per second is considered quite sufficient, however, among the registrars there are models that can shoot HD at 120 fps. The meaning of this speed is to ensure that individual details on moving objects are as clearly visible as possible in slow motion or frame-by-frame viewing.
Recording features
Among the photo and video functions used in the dashcam, we can distinguish
G-sensor,
rotating lens,
live,
HDR< /a>, WDR,
polarizing filter,
DEWARP and
Time Lapse. More about them:
— G-sensor (video saving). A sensor that monitors shocks and vibrations acting on the DVR. The main function of this sensor is to ensure the safety of video materials in the event of an accident: in the event of a strong impact, characteristic of a collision or fall, the recorder with a G-sensor automatically saves the previously recorded video to a non-volatile memory protected from overwriting. Thus, materials about an emergency are not only guaranteed to be saved, but with a high probability remain intact even if the recorder itself is damaged. In addition, the G-sensor is used in
parking mode — see "Functions" for details.
— Swivel lens. The ability to rotate the lens of the registrar horizontally or vertically, and in some cases — on both planes. This feature allows you to adjust the camera's field of view.
— Sound recording. Ability to record sound with a video recorder. First of all, we are talking about recording conversations in the cabin, which can become an add
...itional argument in disputable situations — for example, they will allow you to determine whether the driver was talking on a mobile phone at the time of an accident, whether he noticed the situation on the road, how he assessed it, etc.
— Live broadcast. Allows you to remotely connect to the DVR and monitor what is happening from the camera in real time. It is very important if there is an additional camera in the cabin, when you can track the situation, for example, in taxi services, courier delivery, etc. This function will also become important and useful when a car is stolen, when you can not only see the hijacker from the video from the camera, but also track the route of his movement.
— HDR (high dynamic range). A function that increases the dynamic range of the recorder. Dynamic range is the maximum difference between the brightest and darkest area achievable within a single frame. Initially, this range for digital matrices is small, so an image with large brightness differences (for example, a road against a sunset sky) turns out to be either strongly overexposed in bright areas or very dim in dark areas. HDR addresses this shortcoming and also improves the overall colour quality. This is implemented as follows: the camera takes several frames with different settings and from them forms the finished image. At the same time, this technology is simpler and cheaper to implement than WDR, which is similar in purpose (see below). The main disadvantage of HDR is that this type of shooting increases the blurring of fast moving objects in the frame somewhat.
— WDR (Wide Dynamic Range). A function similar in purpose to HDR described above: it is used to improve the quality of a “picture” that has strong differences in brightness. The key difference between these technologies is that WDR works at the hardware level — due to high-end matrices. This allows you to achieve the required dynamic range within a single frame and do without gluing several frames — as a result, WDR, unlike HDR, does not give a blurring effect and does not worsen the detail of moving objects in the frame. The downside of this quality is the high price.
— Polarizing filter. The presence of a polarizing filter in the main camera of the DVR. Such a filter reduces the brightness of glare arising from strong light on glass, water and other similar surfaces. This greatly improves image quality, especially when shooting in sunny weather.
— DEWARP. A technology used to correct the "picture" obtained using a wide-angle lens. Such lenses are often used in DVRs; one of their drawbacks is their propensity for the fish-eye effect, the characteristic distortion when straight lines in the frame turn into rounded ones. The DEWARP function eliminates this shortcoming — it "bends back" curved lines, correcting the geometry of objects in the frame. Note that such a correction does not always work 100% accurately, however, the picture processed by DEWARP is anyway more reliable than without this technology.
— Time Lapse. A special mode of operation in which video recording is carried out at a slow frequency, which in practice is mainly used for shooting slow processes. Thus, for example, a long journey or a long sunset can fit into a 3-minute video.Functions
—
Radar detector. A sensor that reacts to the radiation of a police radar and warns the driver that the speed of movement can be recorded by the device. DVRs with this function are classified into a separate category - combo devices (see “Type”). Let us remind you that radar detectors are also available as separate devices, but the combo device takes up less space when installed. On the other hand, the “anti-radar” functionality in combined video recorders is generally somewhat more modest than in separately made radar detectors. And combo devices are quite expensive (although, most often, they are cheaper than a pair of a separate recorder and a radar detector with similar capabilities). We would like to emphasize that the presence of this function does not relieve you of the obligation to adhere to the speed prescribed by the traffic rules.
—
Signature recognition. A function of the radar detector described above that improves recognition accuracy and reduces the likelihood of false alarms. To do this, samples (signatures) of emissions from the most popular radar models are entered into the device’s memory, and when a signal is detected, the device compares it with the data in memory. In this way, you can quite accurately determine whether the received signal is the radiation of a radar (and which one), or whether it is just extraneous interference. The disadvantages of detectors with signature r
...ecognition are quite high cost, slightly increased response time and the inability to “recognize” radars that are not stored in memory (however, some models allow updating the signature database).
— Parking mode. A special mode that allows you to record emergency incidents on video while the car is parked; The G-sensor is used for operation (see “Shooting functions”). In parking mode, the recorder is in “sleep” mode, and if the G-sensor detects an impact, full recording starts. In this case, the video from the buffer is “glued” to the beginning of the recording, which allows you to record not only the moment of the incident itself, but also a few seconds before it.
— Motion sensor. Recorder function based on motion detection in the camera lens. Thus, if the recorder “understands” that there is movement in the frame, automatic shooting is carried out. This allows you to configure the DVR to automatically turn on when you start driving, as well as record possible accidents, thefts, and car thefts from parking lots that come into the field of view of your device.
— Voice control. Ability to control the DVR using voice commands. The specific list of such commands (and supported languages) may vary depending on the model. However, in any case, this function contributes to traffic safety: it allows you to keep your hands off the steering wheel and not be distracted from the road when operating the recorder.
— Gesture control. Ability to control the device using gestures. Note that the capabilities of such control in DVRs are very limited: as a rule, a sensor is used for this, which responds to the movement of the user’s hand in front of the device and is capable of performing only one specific action. However, even this feature provides additional convenience and safety (compared to pressing buttons and especially working with menus): moving your hand takes a split second, while the driver is practically not distracted from the road. As for specific functions implemented through gesture control, they may include protecting the recorded video from being overwritten, saving a photo, turning off the sound signal from the radar detector (see above), etc. In some models, such a function is hard-coded in the settings and cannot be reconfigured; in others it is possible to choose one of several options.
— Wi-Fi module. Wi-Fi technology is mainly known as a way to access the Internet wirelessly, but it can also be used to communicate directly with another device. The methods of using this technology in recorders may be different, depending on the functionality. For example, some models are capable of updating map marks for a GPS navigator and a GPS informer database via such a communication (see above); others allow you to upload the captured video directly to the Internet (for example, YouTube); and the most advanced devices with this function have touch screens and, when removed from the mount, can even be used as full-fledged tablets, with the ability to view web pages and install various applications. There are also quite specific possibilities - for example, broadcasting filmed or filmed video to a smartphone or tablet, distributing mobile Internet to other devices (if there is a 3G/4G module), etc. Note that the number of public Wi-Fi access points is constantly increasing, they are available at most large gas stations and are often provided in certain areas of large cities (parks, historical and business districts, etc.). So, accessing the World Wide Web from the recorder without removing it from the car may turn out to be much easier than it looks at first glance.
— 3G/4G modem. 3G or 4G mobile communication module. Designed mainly for data transfer - in other words, for using the mobile Internet; Voice calls for DVRs are considered overkill and are generally not supported. The communication speed in modern mobile networks is often comparable to a communication via Wi-Fi; so the options for using 3G/4G connectivity can be quite varied, depending on the specific model. However, three functions are most often encountered: downloading information about traffic jams and other relevant data (updates for the GPS informer, weather forecast, etc.); work as a GPS tracker (if this function is available - see above); as well as Wi-Fi access point mode, with mobile Internet distribution to other devices (if you have your own Wi-Fi module, of course). If we compare 3G/4G and Wi-Fi, then mobile communications are available almost everywhere, but you have to pay for using it.
— Bluetooth. The recorder has a built-in Bluetooth module. This technology is used for direct wireless communication with other devices; its application may vary depending on the functionality of a particular registrar. One of the most popular options is to broadcast sound to a Bluetooth-enabled radio or to the driver’s headset: these can be various notifications from a navigator, radar detector, etc., signals from the Antison system (see above), and in some models - even music from the built-in player. Another popular application format is exchanging files with a smartphone, laptop or other similar device (primarily copying footage). In addition, other, more specific ways of using Bluetooth may be envisaged. And here it is worth noting that most recorders with this function work on Android (see the corresponding paragraph), so the range of options in them is very extensive - in fact, it is limited to the range of compatible applications.
- Speaker. Own speaker installed in the DVR body. Through such a speaker, for example, audio can be played when watching a captured video, voice prompts from a GPS navigator/informant, signals from a radar detector (see above), etc. However, it is worth considering that the sound power can be quite low, and in a noisy environment it may be difficult to listen to the speaker.External camera
One or more remote cameras in the standard equipment of the registrar, used for video recording of the traffic situation behind the car. In the vast majority of cases, the remote camera is attached to the DVR in
one copy. It covers the rear "stern" of the car and is simultaneously used as an assistant when reversing parking — the picture from the camera can be displayed on the DVR screen in real time. There can be
several remote cameras, which provides a wider coverage of the DVR's field of view.
Video resolution
The maximum video resolution supported by the optional DVR camera. Depending on the design and configuration, we can talk about both a remote camera and a camera for filming the interior (see above for both); this nuance should be clarified separately.
The higher the resolution, the more detailed the image from the camera will be, the more small details will be normally visible on it. On the other hand, high detailing affects the volume of materials to be filmed and the requirements for the “hardware” of the registrar (and, accordingly, affects the cost).
In general, additional cameras of modern recorders can be divided into the following categories:
— SD. "Standard" resolution (as opposed to HD — "high resolution"). A rather modest frame size, which at the same time allows you to significantly save memory for video recording and is suitable even for low-cost recorders. Specific resolution options include, but are not limited to, 628x582, 640x480, and 720x480.
— HD 720p. The traditional, most popular resolution for this video recording standard is 1280x720. In addition to it, registrars also found 960x720 (aspect ratio 4:3) and reduced in height 1280x480. HD is the most modest of today's high-definition standards, but still provides pretty decent detail.
— Full HD 1080p. The "classic of the genre" for this standard is the resolution of 1920x1080, however, there are other values in registrars, including very speci...fic ones — such as 1440x1080 (4:3 aspect ratio) and 1920x540 (halved vertical resolution). This is a fairly solid indicator even for the main camera of the registrar, and there is no need to talk about additional ones.
— Super HD. Not a particularly popular standard in video technology, which, nevertheless, has found application in video recorders. Most often provides a resolution of 2304x1296, which provides even more
Frame frequency
Maximum video frame rate supported by the optional DVR camera. Depending on the design and configuration, we can talk about both a remote camera and a camera for filming the interior (see above for both); this nuance should be clarified separately. Anyway, it is with this frequency that the shooting is carried out by default.
The higher the frame rate, the clearer the moving objects will be on the video, the less they will be blurred and the less “jerky” the video itself will be. It is believed that the most comfortable for the human eye is a speed of 24 to 60 frames per second; a lower frequency is already perceived as a “slideshow”, and a higher one only increases the amount of material being shot, without giving a visible increase in quality. At the same time, registrar cameras can also provide higher filming speeds than 60 fps — this provides good visibility of individual moving parts in slow motion or frame-by-frame playback.
Screen size
The diagonal of the display installed in the DVR.
A large display, on the one hand, provides additional convenience, on the other hand, it affects the dimensions and price of the entire device. Therefore, manufacturers choose a diagonal in such a way that the device can be used normally and at the same time it is not too expensive and bulky. So, for a classic registrar that does not have additional functions, a small display is enough —
2 – 2.5",
1.5 – 2", or even
less : it completely allows you to manage the settings and control what exactly gets into the frame, and to fully view the footage, you still need a computer, TV or other large screen. A size of
2.5 – 3 " by the standards of such devices can already be called average, and screens of
3" or more are typical mainly for fairly advanced models, often with an abundance of additional functions.
Also note that there are models that
do not have a display at all. To control the operation parameters and check the position of the frame, such a recorder is connected to an external device — for example, to a smartphone via Wi-Fi.