CCTV systems that respond to moving objects are more cost-effective and efficient. Motion registration is provided in different ways. A video recorder with a motion sensor can be a construction of a video camera, a sensor and a recorder, or the software of the device.
Varieties of DVR systems with a motion sensor
A video recorder is a device designed to process a signal from a camera and form an image. The user has to deal with two of its main variations: a modification used to organize a video surveillance system in an apartment, and a device that is installed in cars. The first option is quite large, it is supplied with a hard disk and replaces a PC in a video surveillance system. The car version is very compact, equipped with its own camera, but has much less memory.
There are several varieties of the device.
Digital
DVR - A digital video recorder compresses the video signal received from an analog camera into a digital one. The signal is transmitted over a coaxial cable. In this form, the data is written to the hard disk or transmitted to the network. Most models are equipped with an Ethernet interface for connecting to a network.
The network option can be connected to the Internet, store the recorded video on the DVR itself or in the cloud. Online monitoring and recording playback are available.
Network
NVR - Network or IP recorder is designed to work with corresponding cameras. The latter independently compress the signal and transmit it to the recorder via the Internet or over a local network. They usually support motion sensor function. In this case, it is software.
The device receives the settings during production. You cannot change them. The user needs to define all the required parameters and, in accordance with them, select the recorder.
DVRs are classified by the number of cameras that can be connected to it - from 4 to several hundred; and by the number of monitors - from 4 to 10. This takes into account the resolution and data volume from each camera. A device capable of handling 30 2MP cameras will not be able to handle 30 higher performance devices.
Mixed
Such devices are capable of working with IP-cameras and analog ones. In fact, any DVR with Ethernet interface can record both analog and digital signal if it belongs to the middle or high class. The hybrid options are just a way to highlight the more expensive models with the extra port.
For vehicle
The motion sensor of the DVR is intended only to guard the car. It is useless when adjusting the shooting mode while driving. There is another feature: the camera lens looks in front of itself, which allows you to detect a moving object before the sensor picks up the movement. If you try to activate the sensor while driving, you get a torn recording, consisting of separate pieces.
Activate the motion sensor when leaving the car in the parking lot.In this case, you need to turn the camera lens inward so that the sensor reacts to movement in the cabin. Thus, it is possible to fix the break-in of the car.
With night vision
The ability to shoot at night depends on the design of the outdoor camera. There are 2 options: IR illumination can be built directly into the camera or provided by an IR illuminator. The image is flat, black and white, but quite clear.
The car DVR can also be equipped with IR illumination. However, this option is useful when the car interior is being monitored at night. The IR signal passes through the glass poorly, so the recorder can only detect the appearance of an object in the immediate vicinity.
Self-powered
In the house, a mains-powered appliance is more often used. This is more profitable, since the video recorder of the security system consumes a lot of energy. In cars, self-powered models are more convenient, since the car often needs protection just during stops.
When buying, you need to evaluate the capabilities of the battery. There are models in which it is designed for a very short life, only to retain the recording files when the power is turned off. Autonomous DVRs are equipped with powerful batteries.
Specifications
The custom qualities of the fixtures are the parameters for product selection.
- Capacity - recording from a camera with a good resolution can take up to 1 GB, so good models are equipped with hard drives up to 7 TB.
- Resolution - determines the clarity of the recording. The minimum resolution is 704 * 576 pixels.
- Speed - indicates at what speed the data is processed with the set number of channels. The efficiency depends on the number of channels: with a total speed of 100 frames per second, 8 video cameras will transmit a signal at a rate of no more than 12 frames.
- Data transfer rate - recording time or bandwidth. The faster the DVR with motion sensor, Ethernet interface and night vision, the better.
- Audio signal - models record audio from at least one camera. The transmission of audio files over the network is only possible with some recorders.
- Control - through the mouse, remote control or control panel on the device.
The car DVR is also evaluated according to the characteristics of the motion sensor. It is necessary to take into account the radius of its perception, the possibility of wireless operation, the type of motion sensor. The control function via a mobile application can also be useful.
Motion sensor classification
The devices are divided according to the method of recording what is happening: photo and video filming.
Photo fixation
The photo recorder performs only a security function. The device takes pictures, sometimes with a very short period of time. Frames weigh a little. The photo device allows you to get an image of what is happening in front of the car.
They are rarely used by motorists as they are less useful in an accident. Traffic police surveillance cameras often function in the photo mode: this is how they get pictures of offenders.
Video fixation
The video allows you to get a complete picture of what is happening while parking and driving. A large memory card is required for recording. The device is often equipped with a self-contained power supply, since the DVR has to work all night, and video recording requires more power than photographing.
Principle of operation
The algorithm of action for most of the models is the same. Some points can be adjusted manually.
- When the car is stopped, the dash cam enters parking mode. Some models need to be translated manually. This is sleep mode: recording stops, but the motion sensor remains active. If a movement is detected near the machine, the recorder is turned on by a signal from the sensor.
- Parking mode is exited automatically after starting the engine or manually. In this case, the recording is carried out continuously.It is better to turn off the motion sensor at the time of the ride, as it will try to regulate the camera.
Parking mode, if the car is left in the garage, can be deactivated by pressing the ON / OF button. If the unit is equipped with a rechargeable battery, recording is automatically disabled when the battery level drops.
Registrar entry
The recording is created by using 3 parts:
- Buffering - Overwrite. These are 3-5 s of static recordings, which are needed to compare the previous situation with current events. These frames automatically complement the recording.
- Motion - recording is continuous as long as the sensor is active.
- 2 buffering - after recording. When the motion ends and the sensor turns off, the recording stops. However, the device takes a new static picture and adds these frames to the end of the recording.
The generated record looks coherent, but does not include unnecessary snapshots.
Setting up a DVR with a motion sensor
The settings are made after installation. Most car recorders are automatically activated after being turned on. To make the setting, the recording is turned off and goes to the menu:
- Set up the language, date and time in the corresponding column.
- In the "Resolution" section, select an indicator - the optimal resolution is considered to be 1920 * 1080.
- Indicate the duration of the video - usually 5 minutes.
- Cycling is activated or deactivated. If overwrite is enabled, when the memory card is full, the very first clip is erased and the last clip overwritten.
If necessary, indicate additional parameters: start recording when the sensor is turned on, auto power off the monitor, audio recording.
Famous manufacturers
The following devices are most popular on the Russian market:
- Digma FreeDrive 500 GPS Magnetic is a car DVR with a 2-inch screen. Equipped with a battery, has a viewing angle of 140 degrees.
- KARKAM Q7 - equipped with a GPS-module and a high-power processor. 450mAh rechargeable battery for long life.
- Ubiquiti UniFi NVR 2TB - Network Video Recorder for Security System. Works with 20 cameras, the hard drive is designed for 2 TB. Popular for its low power consumption.
- HikVision DS-7204HTHI-K2 is a hybrid model. Supports 16 cameras, of which 4 can be analog. Available resolution - 2 megapixels.
DVRs with motion sensors are produced in different price segments. It is not difficult to find the right option for video surveillance of the territory and car security.
