PREDICTION MODE SELECTION METHOD, VIDEO ENCODING DEVICE AND STORAGE MEDIUM

Disclosed are a prediction mode selection method, a video encoding device and a storage medium, belonging to the technical field of video encoding. The method comprises: acquiring a first optimal intra-frame prediction mode of a down-sampling unit corresponding to a target prediction unit, wherein the down-sampling unit is obtained, by means of division, after an image frame that the target prediction unit belongs is down-sampled, and the first optimal intra-frame prediction mode is obtained by performing pre-encoding analysis on the down-sampling unit; according to the first optimal intra-frame prediction mode, adding a candidate intra-frame prediction mode to a candidate mode set; according to a second optimal intra-frame prediction mode of an adjacent prediction unit corresponding to the target prediction unit, adding a candidate intra-frame prediction mode to the candidate mode set; and according to a prediction residual and an encoding cost value corresponding to the candidate intra-frame prediction modes in the candidate mode set, determining an optimal intra-frame prediction mode of the current prediction unit. The embodiments of the present application achieve the effect of improving a video encoding speed while reducing the consumed time of intra-frame prediction mode selection.