the process of changing computer information that is stored in a particular code (= a language used to program computers) into another code

The software provides "transcoding" - translation between standard web pages written in standard HTML (Hypertext Markup Language) and Wap's WML (Wireless Markup Language). 该软件提供“转码”功能——在用标准HTML语言（超文本标记语言）和用无线应用协议规定的WML语言（无线标记语言）编写的标准网页之间进行翻译。

the process of changing a media file (= a file that contains sound and video) from one format (= the way in which information is arranged and stored on a computer) to another

It is a very nice computing machine for DVD transcoding. 这是一款非常不错的DVD转码计算机。

Once on the hard disk all sorts of transcoding is possible. 一旦在硬盘上就可以进行各种格式转换。