Network video storage server system

The invention discloses a network video storage server system which comprises video monitoring equipment, a network video storage server NVR (network video recorder), a client side, and a network; the network video storage server NVR uses standard protocols and is connected with the client side through the network or is directly connected with the client side; and the network video storage server NVR comprises a video acquisition storage module, a video quality detection module and an alarm module. The network video storage server system performs quality diagnosis to each video in a roll poling manner, can make correct judgments for common camera failures of video images, such as snowflakes, scrolling, vagueness, screen freeze, gain imbalance and out-of-control cloud deck, as well as for unlawful acts like flagrant shelter and damage to the monitoring equipment, and issues alarm information.