A new method for fast data collecting in rotating-frame NQR imaging is reported. A single unidimensional spin-density profile is composed by this procedure, recording the evolution of the magnetization during the course of the nutation. Hence, a complete data set necessary for the reconstruction of a 1D profile is directly recorded by a single scan provided by a train of short and intense radiofrequency pulses. A reduction of one or even two orders of magnitude in the time necessary for data acquisition is achieved. One-dimensional profiles and 2D spin-density images of geometrically simple objects are compared, using data sets obtained by the present single-experiment and the previous multiexperiment methods.