Image compression is typical in all modern data recorders. Image or video is compressed using a particular format before it is written onto the storage disk. Thanks to the latest advancements in CCTV technology, we now get to experience various kinds of compression techniques. And the research for new and better compression technology is also carried out, promising more compression format.
The typical compression technique that most devices use is MEG-4. However, this is not one format, and there are other versions of MPEG-4 as well. In fact, the most widely acknowledged ne compression technique, H.264 is actually the MPEG-4 Part 10. H.264 is starting to find favour for applications involving high-resolution images.
For a given system, applying more compression will undoubtedly provide a longer recording time for a particular size of hard disk, but it will also mean that more detail is lost from the recorded images
It is not very necessary to understand the in-detail technicalities of these compression formats and relative qualities of the various compression systems. Nevertheless, it is vital to understand one crucial fact: All these systems have some level of video losses. To explain this further, if you take a system, and apply more and more compression onto it, it will undoubtedly give you a longer recording time for a particular size of hard disk. But, on the other hand, it will also cause you to lose more detail from the recorded images.
This brings us to the rule of thumb in video compression – if you ever find the recording capacity of a DVR to be way beyond good to be practical, then, it probably a not good one to go for, especially if the recorder also has an charmingly low price tag. The high capacity will almost certainly have been achieved by using excessive compression, which will inevitably mean poor playback quality.