A color-imaging process is proposed to find the stream-lines for the visioplasticity method; in this procedure models of various color-patterns are set up. The images from specimen scanning of the experimental data are compared and recognized with those models, the stream-lines then being obtained easily. Plane-strain extrusion through a cosine-curved die with a 2:1 extrusion ratio is used for the illustration of the procedure. The computed stream-lines are used to combine with the model of the finite flow-line-region method. The calculated results for the velocity and effective-strain fields are also presented, showing that this procedure gives reliable results for visioplasticity.