Recent work to study excitation effects on an acoustically excited jet flow is reported. Emphasis is placed on integreated visualization and digital image processing of high resolution, sequential planar gas concentrations of some characteristics of the large scale vortical structures of the acoustically excited jet flow, such as multi-eddy merging, vortex braids formation, eddy evolution and entrainment processes, jet boundary expansion, etc. The digital image processing technique employed there extends our previous work (Chao, et. al. 1990) for optimal threshold filtering of the background noise and in situ calibration of camera and illumination distortions. A compact, low-cost, automatic frame acquisition and analysis system is developed for mean and r.m.s. planar gas concentrations and automatic jet boundary identification. Also, stroboscopic images are created for detailed sequential study of a quick-changing process using a low framing-rate camera by suitably controlling the acoustic excitation frequency and the jet flow.