1. A medical image processing apparatus, comprising: estimation circuitry configured to estimate activity of a myocardium across a plurality of images at different time phases from a group of images, where the plurality of images containing the myocardium are chronologically arranged; and tracking circuitry configured to set a search range for tracking the myocardium in the group according to the activity of the myocardium and perform the tracking, wherein the estimation circuitry is further configured to estimate, according to a first region set on at least one image in the group, a second region corresponding to a same object part as the first region on another image in the group, and the tracking circuitry is further configured to: seek, in the second region, a second part corresponding to the same object part as a first part in the first region; set a search range in the another image with the second part as a center; and search for a third part matching with the first part in the set search range to perform image tracking.