We propose a modified method of acquisition and analysis of Spectral Optical Coherence Tomography (SOCT) data to provide information about flow velocities in three dimensions. Joint Spectral and Time domain Optical Coherence Tomography (joint STdOCT) enables flow velocity assessment and segmentation of flows. STdOCT method is based on direct detection of Doppler shift that arises in time during the measurement. New scanning protocols and analysis tools are proposed to create velocity distribution maps of the retina and to segment and visualize 3D flows. STdOCT segmentation is more sensitive than methods based on phase measurements and calculations are more straightforward than other techniques, which require more complex experimental setup and more sophisticated numerical tools. We also discuss parameters, which improve the flow based segmentation procedure with special attention paid to the problem of broadening of flow velocity distribution.