  We propose a useful method for mapping large-scale velocity fields in the
solar photosphere. It is based on the local correlation tracking algorithm when
tracing supergranules in full-disc dopplergrams. The method was developed using
synthetic data. The data processing the data are transformed during the data
processing into a suitable coordinate system, the noise is removed, and finally
the velocity field is calculated. Resulting velocities are compared with the
model velocities and the calibration is done. From our results it becomes clear
that this method could be applied to full-disc dopplergrams acquired by the
Michelson Doppler Imager (MDI) onboard the Solar and Heliospheric Observatory
(SoHO).
