As camera resolutions continue to climb higher, and with HD and megapixel video systems being deployed across a wider variety of customers and vertical markets, sending the larger video files generated by those cameras across networks has become a major issue for integrators and end users.
Three major compression algorithms — H.264, M-JPEG and MPEG-4 — have been used in the industry to date for reducing the size of video files. Of these, H.264 has become the de facto standard embraced by most, if not all, of the camera manufacturers, primarily because it is the most efficient for reducing file size for transmission and storage without also reducing image quality. File sizes can be as much as 80 percent smaller than comparable M-JPEG files. The difference is in the way video frames are selected for compression. H.264 analyzes the video and sends only frames of what has changed from one frame to the next, such as when there is motion in the scene. M-JPEG is a pixel-based technology; it determines which parts of each pixel must be compressed and discards the rest to shrink file sizes.