As opposed to classical method of acquiring test data point by point in experimental modal analysis, computer vision method is adopted and studied in this work to offer full-field test data at once. The proposed method is validated by capturing geometric data of three buckled steel plates by camera, of which data is then used to generate the plates’ vibration modes. Comparing to the ideal geometry of the manufactured plates used in finite element analysis, the proposed method is validated to be effective in the study of vibrations of buckled components.