An embodiment of the present disclosure provides a method for acquiring position information of a transform block. The method includes obtaining a splitting manner of an image block, obtaining splitting direction information according to the splitting manner of the image block and a splitting layer number of a transform block, or obtaining splitting direction information according to the splitting manner of the image block and a numerical relationship between a width and a height of a transform block, and obtaining position information of a post-splitting transform block according to the splitting direction information. In embodiments of the present disclosure, splitting direction information is obtained directly according to a splitting manner of an image block and a layer number, and then, size information of a transform block is coded according to the splitting direction information, thereby effectively reducing complexity of a coding process.