Picture transmission control system, and security protection and transmission method of each related end

The invention relates to the technical field of picture transmission of an intelligent terminal, and brings forward a tachograph picture transmission control method. The method comprises the following steps: a tachograph obtains an object picture in response to a user snapshot instruction and storing the object picture to a local storage medium; the tachograph automatically uploading the object picture to a mobile terminal through a first channel; at the same time, the mobile terminal automatically uploading the object picture automatically obtained from the first channel to a cloud end through a second channel; and the tachograph, according to a comparison result list which is obtained from the first channel and is fed back by the mobile terminal, deleting an object picture, specified to be stored in the local storage medium, in the comparison result list. The invention also relates to a picture security protection and transmission method and a corresponding terminal. According to the invention, security protection and automatic real-time transfer of picture files are realized, and picture loss generated when pictures are stored at a tachograph end and are covered due to a limited storage capacity is avoided.