Mixing line detection method, mixing line detection system, network video camera and monitoring system

The invention provides a mixing line detection method. The method comprises performing a gray scale, a frame difference and a two value on two adjacent frames of video monitoring images, obtaining more than two region blocks intersected with a mixing line region, generating a dividing line of the region blocks according to a mixing line direction, calculating gradient values of all region blocks on two side edges of the diving line to obtain states of the region blocks, performing statistics of all the region blocks, and then obtaining a state of a target object corresponding to the region block. The invention further provides a mixing line detection system. The invention further provides a network video camera and a monitoring system, and execution efficiency is improved.