The Coded Width, which is found in a number of files, is a subset of the overall size of the file. Like the other subsets, such as the width of an image as well as the narrowed image width, the Coded Width defines a particular width in the file.
In the case of Coded Width, it expresses the width of the video image, file document, or even portions of an audio file (e.g., artwork for the covers) in the way it is encoded inside the file. The cover art can, and often is different from the size of the original file, and it is modified to meet a particular minimum or norm.
Together the Coded Width and The Coded Height create the coded dimensions of the file.