Seismic imaging method and device for direct imaging from undulating surface

The invention provides a seismic imaging method and device for direct imaging from an undulating surface, through which an imaging section can be directly obtained from a common shot point gather and the obtained processing result is more objective and real. The imaging method comprises the following steps: 1, according to a position of a shot point and a position of a detection point of the common shot point gather, selecting a datum plane and presetting a position of an imaging plane original point at certain interval on the datum plane; 2, determining a position of a virtual image point according to the position of the shot point, the position of the detection point, default scanning time and average velocity of a medium; 3, determining a position of a dew point and a position of a reflection point where the dew point is reflected to the detection point through the shot point by combining the position of the imaging plane original point based on positions of the shot point, the detection point and the virtual image point; 4, calculating normal direction round trip traveling time from the imaging plane original point to the reflection point and time correcting value of the imaging plane original point compared with the exposure point; 5, performing ellipse expansion tangent interference superposition imaging processing to obtain a zero-offset time section.