A computer vision approach for recognition of the engagement of pigs with different enrichment objects

•It is the first time to use computer vision to recognise pig enrichment engagement.•A HSV colour space-based method was proposed to track the object region of interest.•InceptionV3 and LSTM were used to extract discriminative spatial-temporal features.•This algorithm has reference value for classifying similar behaviours of pigs.•Pigs preference to 3 enrichment objects was also determined in this study.