On the subject of DVRs, I’ve often been asked what H.264 means and why it’s important. Basically, H.264 is currently the best format for compressing video, and is used on a variety of popular technologies, from Blu-Ray to YouTube. The ability of a security DVR to be able to compress video is not only important, it is essential.
Think of the common file types that are used universally – WMV, MPEG, and AVI. A friend sends a video file to you, you right click onthe image, select properties, and then you see the image’s file type. Those file types each have their own properties or video compression type. Now, consider the size of that image or file, and how much space it may consume on the hard drive. You can then fathom why it’s important to have the ability to compress that video file in order to save space. It’s also important, especially with video surveillance, that with this compression, the quality of the video footage is not decreased.
The intention of H.264 is to establish an acceptable balance between viewing quality and the size of the video file, so that the maximum amount of video can be stored on a hard drive without losing the detail and quality of the video. When speaking of a DVR and CCTV footage, H.264 is imperative not only because of the larger quantities of actual footage (that can span from a few hours to several weeks), but also due to the various purposes for surveillance. Depending on the application, such as a government facility or a retail store that is trying to monitor theft, achieving the highest possible frame rate is essential to identify problems accurately. It is best to stay above at or above a 15 FPS frame rate because once you drop below that, the footage becomes choppy and isn’t nearly as reliable.
H.264 DVRs aid in these endeavors because compressing the video allows for maximum storage on the hard drive, while producing the highest resolution and frame rate capable of the unit and cameras being used. The two main types of video compression for CCTV are H.264 and MPEG/MJPEG. H.264 is the latest technology in codecs, and will drastically reduce both the bandwidth and storage requirements of video files while still maintaining high-quality images.