Inclusion Criteria:  Bile duct segmentation model 1) Male or female aged 18 or above; 2) Who needs ERCP,MRCP and its related tests are needed to further define the characteristics of digestive tract diseases； 3)The images of MRCP and ERCP are clear; 4) Able to read, understand and sign informed consent; 5) The investigator believes that the subject can understand the process of the clinical study and is willing and able to complete all the study procedures and follow-up visits and cooperate with the study procedures. Bile duct matching model  In addition to the criteria mentioned in the bile duct segmentation model, the bile duct matching model should also meet the following criteria:  Able to complete MRCP in prone position; Bile ducts are almost completely visible in MRCP and ERCP.  (3) Clinical trials  In addition to the criteria mentioned in the bile duct segmentation model, the clinical trials should also meet the following criteria:  Able to complete MRCP in prone position; Patients requiring biliary drainage by ERCP due to malignant hilar biliary obstruction.  Exclusion Criteria:  Bile duct segmentation model and bile duct matching model 1)Has participated in other clinical trials, signed the informed consent and was in the follow-up period of other clinical trials; 2) Drug or alcohol abuse or psychological disorder in the last 5 years; 3) Patients in pregnancy or lactation; 4) The investigator considers that the subjects were not suitable for MRCP, ERCP and related tests; 5)A high-risk diseases or other special conditions that the investigator considers inappropriate for the subject to participate in a clinical trial； Clinical trials  In addition to the criteria mentioned in the above, the clinical trial must not meet any of the following criteria:  Previous gastrectomy; Stent replacement; Pyloric or duodenal obstruction.