||Streaks play a major role in the process of turbulent generation. Numerous studies have been performed to characterize them, most of which used only single point measurements and only a few characteristics were studied. To investigate the streaks in more detail, a stereoscopic particle image velocimetry (SPIV) experiment was conducted to record 2D3C velocity fields in ten planes parallel to the wall from y + = 14.5 to y + = 48 at Reynolds number Re θ = 7,800 in a fully developed turbulent boundary layer along a flat plate. This study develops a method based on pattern recognition to detect streaks from velocity fields obtained by SPIV and characteristizes them in depth. The results are in good agreement with the previous studies and expand significantly the information about the characteristics of the streaks.