The factors that contribute to the explosive growth of megapixel network cameras are their abilities to provide wider coverage and exceptional detail. A 2-megapixel network camera can cover an area 6 times larger than a VGA network camera. With a 2-megapixel camera compensating for 6 VGA cameras, the installation costs can be signifcantly reduced.
Transmitting and storing a full view in megapixel takes up valuable bandwidth resources and is, in many cases, unnecessary, especially when the scene contains no changes. VIVOTEK has adopted cropping functions to allow for the removal of unnecessary information and the transmission of video concerning only the area of interest. As a result, bandwidth and storage requirements as well as CPU loading can be drastically reduced.
VIVOTEK megapixel network cameras are equipped with electronic pan/tilt/zoom capabilities that enable users to move to a target region instantly for close-up shots by simply clicking on the video feeds on their screen rather than moving the camera physically. With ePTZ, bandwidth and CPU can be used more efficiently because only the image of the target region is encoded and transmitted. ePTZ also prevents a megapixel camera from mechanical wear and tear since it contains no moving parts.
H.264 is a video compression standard boasting much higher compression performance than MJPEG or MPEG-4, and can thus further reduce file sizes and bandwidth usage. With a compression ratio of 90%, a 2MB image can be reduced to 20KB using H.264, achieving 50% of bandwidth conservation compared with MPEG-4. With H.264, VIVOTEK megapixel solutions can guarantee uncompromised image quality with lower bandwidth and storage requirements.
VIVOTEK megapixel network cameras allow each video stream to be delivered in a different resolution, frame rate, and image quality for individual quality or bandwidth demands. As such, the camera can simultaneously transmit a small CIF image for real-time monitoring and a large megapixel image for storage, drastically reducing CPU loading since no extra decoding or resizing is required for displaying the CIF image on the screen. Multiple streaming also enables dealing with camera images on different platforms simultaneously such as mobile phones and PCs.
Activity Adaptive Streaming
VIVOTEK megapixel network cameras support activity adaptive streaming to dynamically allocate bandwidth with a configurable frame rate according to different needs. For example, during normal monitoring when only recognizable images are needed, the frame rate can be set low, e.g. 1 fps, to reduce bandwidth usage. In an event-triggered situation, the frame rate will increase to a higher level, e.g. 30 fps, to allow for smooth and high quality video feeds. As a result, VIVOTEK megapixel network cameras can optimize bandwidth usage during monitoring while ensuring superior image quality during recording.
The rapid advancement in memory card technologies and capacity has resulted in the proliferation of the use of on-board storage on SD/SDHC cards in IP Surveillance. Having video data stored on such memory cards to be transmitted if needed significantly reduces bandwidth and storage requirements. VIVOTEK's megapixel network cameras are built with a SD/SDHC card slot for maximum storage efficiency.
When monitoring an area, a megapixel camera provides superior image quality compared to a standard resolution camera. As illustrated below, which compares a VGA, 1.3MP, and 2MP image, the license plate in the 2MP image can be easily identifed, but not in the case of VGA resolution. Thus, in applications where accurate identifcation is required, a megapixel camera image can provide detailed information that is obscure when using a VGA camera. The improved pixel count also allows for the application of ePTZ technology, which will be discussed later.