Line structured light techniques, especially laser scanning, are preferred for commercialized three-dimensional (3-D) shape acquisition. Typically, a captured line stripe is to be detected spatially within a single image, and the detection may fail if there are ambiguities in the image. We present a decoding strategy for line structured light patterns. Over all recorded line-patterned images, by means of Fourier analysis along the time axis for each pixel, a phase map is computed and employed for 3-D reconstruction. The phase error is theoretically analyzed. Experimental results demonstrate that, compared with typical approaches based on spatial stripe peak detection, the proposed method achieves comparable accuracy and, most importantly, successfully handles the issue of ambiguities.