What do you need to record from cameras to a remote computer?

Question

CCTV

Need help with CCTV.
There are three offices in different cities, I want to install video surveillance in them with 2 cameras per office, and so that the recording from these cameras is conducted, say, at my house on the server. Assemble a computer to record. What is needed for such organization of video surveillance or is there a way that will be easier? Maybe someone can even advise certain models of equipment? The quality of sound and picture is important.

Answer 1

If the quality of sound and picture is important to you, while you want to record from six cameras, then a home server is excluded. Subscribe to a cloud-based video surveillance service, such as ivideon. Buy cameras that are compatible with it, that can work with it without additional computers, and the picture quality from which you are satisfied. Connect your cameras to the service and enjoy.
Just keep in mind that a good picture eats up traffic, at your offices either everything else will slow down, or the video will sag when something is downloaded there.

Answer 2

I will describe a typical solution to your problem (that is, the solution may be different, with its pluses and minuses, but in my reality this is the most common):
All recording is done locally. Each office has a separate cheap video recorder with a hard drive. The DVR is connected to the local network of the office and has access to the Internet through a router, you can forward ports on the router for remote access to the DVR. Further different options.
1. in terms of the type of cameras (google the pros and cons on your own):
1.1. ip-cameras connected to the local office network; for them, the registrar is NVR or hybrid;
1.2. AHD cameras are still relevant - they are connected to the registrar with a good old coaxial cable; registrar - supporting AHD or hybrid;
2. in terms of access to video from your home computer:
2.0 in most cases, no one needs constant access; they called from the office "we have an incident, we need to look" - we go in remotely and look, if necessary, download the necessary piece of the recording to our computer.
2.1, most registrars have the ability to connect to the cloud, and you can also go to the cloud from your computer or smartphone and watch the picture in real time. It is quite acceptable for an ordinary office - it is unlikely that the Chinese will find interesting secrets there :)
2.2 put a registrar at home - hardware or software - and register access to remote registrars in it. You will need static white IP addresses in each office (although there is DDNS, but for me DDNS is an unreliable buggy option). The disadvantage of option 2.2 is constant traffic.
PS ip-cameras can send two streams at the same time - a "fat" main stream for local recording with good quality and a "skinny" alternative stream with a worse picture for transmission over the Internet, so as not to clog the channel too much.

Answer 3

If you buy ip cameras with simultaneous connection support, then you are in luck (there are definitely such ones, they have two links for rtsp, cheap ones can also have it, but there will be not a word about it in the documentation, in general, take a camera from the price list, google rtsp, study reviews etc. in some cases it is even called a hack, be careful, most ip cameras give rtsp without authorization or authorization is difficult to automate, without stream encryption, etc. in general, it is very strange to make a network of cameras open to the world).
Take openrtspset it up to record (for example, by files for several minutes), but be careful, with a dozen cameras the traffic is such that your home Internet may not be able to cope, and the network of the enterprise may turn out to be weak. It is better to place the storage server in the organization itself. View saved files already in the usual way - a file server, synchronization, or your choice. Separate pieces of video can be combined into a playlist, all players show this without problems.
To watch the video, simply connect using any player (the same vlc or mplayer or ffplay) via rtsp via the second link to the camera. Set up links directly in the explorer or a simple html page (google rtsp playback in the browser, it will almost certainly be a flash player but controlled by javascript), where the link will be a picture from the same cameras, usually cameras give the current picture as a jpeg special link. In its simplest form, the task does not look complicated (if you only look), but if you also need control (panning cameras, on / off led lighting, night vision, zoom, etc.), then you will have to get confused and study the api of these cameras ( reverse their html page, most likely there are simple post requests). I would recommend making links to the admin panel of each camera on my control page, i.e.
If the camera does not know the second stream, in theory it is possible to assemble a layer from ffmpeg (on the server where you store the video), but everywhere I have seen examples there are either non-obvious glitches or a very large delay (in ten seconds) of the broadcast.
ps cheap cameras (<=$15) with which I played at home usually have problems with the return of the mpeg encoded stream, for example, camera freezes. There were no problems with mjpeg, but a very heavy traffic stream comes from them (a dozen megabits if HD) and not a single network channel will push a dozen of these cameras out, so you will almost certainly only have the option of transcoding video on your server. What kind of hardware to choose in order to transcode a stream from a dozen cameras is a separate conversation, if you find free software that can do this using a GPU, everyone will thank you.
In general, do not save on the camera and do not chase wifi in them, there is no point in this, since electricity still needs to be supplied, it is better to make sure that there is a possibility of power supply via POE, i.e. 1 wire for mains and power (make sure that the standards on the switch and the camera match, they sometimes have their own non-standard splitters).