A video imaging and counting system for use in counting moving particles. A video camera (14) is used to monitor the interior of a boiler (12) for carryover particles (46) of burning fuel. A video signal produced by the camera is electronically filtered according to a software algorithm implemented by a microcomputer (116). The video signal is digitized and at least a portion of it is processed and filtered to eliminate the fixed background noise, and variations in illumination across each image. Hot particles appearing as streaks in the image are counted when adjacent time/spatially filtered data points exceeding a threshold level lie in a defined ranged of angular trajectories. The range conforms to the expected motion of a particle entrained in hot gas flow within the area of interest in the boiler. An enhanced image of the moving particles filtered by a similar algorithm and the particle count are displayed on a video monitor (22).