If we need to be laconic, dubbing translation is described as transmitting the words within the source language to the target language. The speaker must speak in the same period in target language as much as within source language.In the target language, the speaker must say the words from the source language in exactly the same period of time as they were spoken. Synchronization of the speaking patterns is critical to an effective translation.
In other words, s/he must open and close his/her mouth in the same time span. Voices in the background might be translated if they are significant to effect the contents of the movie or other visual material. There are two stages in the dubbing translation. To begin with, translation and second dubbing or recording. If the first stage is done careless manner, you can not expect a good outcome. Both stages must be fulfilled thoroughly in this sense. Let alone technical equipments, recording stage also requires dexterous artists and players who know what dubbing is, and are wall familiar with specialties like stress, intonation, diction and the like those which are required techniques concerning dubbing. It is a painstaking job that is not tolerable to being malapropos.