Target detection model training method and device and target detection method and device

The invention relates to a target detection model training method and device and a target detection method and device. The training method comprises the steps: inputting an obtained feature map of a training image into a cascading head network of the target detection model, so as to obtain a prediction thermodynamic diagram for the prediction output of a central point of each stage of head network, taking each position point in the prediction thermodynamic diagram output by the first-stage head network as a target position point, and taking the position point with the probability greater thana threshold value in the prediction thermodynamic diagram output by the previous-stage head network as the target position point in the prediction thermodynamic diagram output by the next-stage head network for the rest of the head networks; and training a target detection model according to the probability difference between the prediction thermodynamic diagram output by each level of head network and the corresponding l