DVR Card Differences
At the heart of any DVR solution is the video capture card, also known as a DVR board or encoder. This component, more than any other, will determine the effectiveness and quality of the DVR system. The encoder is the “engine” which powers the vehicle. This video capture card contains, a hardware or software based Codec, which performs the vital operation of capturing, compressing and decompressing packets of video data. Codec, which stands for “compression-decompression,” will be discussed in greater detail later in this guide.
There are consumer quality, economy cards and components and industrial/commercial grade ones too. There are some with the current technology and others with decade old technology.
Most video capture board and encoder “manufacturers” do just that, manufacture the “board” – that green thing with a bunch of neat looking colorful soldered components.
In reality, these companies are just assembly plants. This is common throughout much of the consumer electronics industry where nearly all companies create products assembled from other companies’ components, including all the household names you are familiar with.
So what is it then that makes the difference between, a top notch product and an average to sub-standard one?
We mentioned earlier that the video must be compressed and decompressed. This function requires “processing.” Processing is performed by a processor. The processors for decoders are similar in nature to a PC and come in various speeds and abilities. Just as in an Intel processor for a PC you have a Celeron and a P4, etc. Then within those architecture categories are different levels of processing power, such as 1.4MHz to 3+MHz; different bus rates; etc., so goes processors for encoders and decoders. For the gaming environment, the most powerful processors are required to meet acceptable regulatory standards.
In many cases there are multiple processors on a single encoder card in order to maximize performance. Some will have one processor for each channel of video; the more efficient ones are capable of encoding multiple channels of video on a single processor. Once you have the power of the encoding processors, you then require a powerful and efficient compression algorithm to perform the function.