Specification
MicroDVD subtitle files have the .sub filename extension. These files may come along with a video file and/or created/modified by the user. Media player applications that support external subtitle files are usually responsible for locating correct .sub files.
MicroDVD subtitle files consist of multiple lines, each defining a portion of the subtitle text that must be displayed between certain given video frames. The line syntax is:
{start-frame}{stop-frame}Text
For example, if "Hello!" is to be displayed during the first 25 frames of a digital video, clip or movie, the corresponding .sub file must contain the line:
{0}{25}Hello!
The duration of the text being displayed depends on the frame rate of the corresponding video file. For example, if the frame rate of the corresponding video file is 25 frames per seconds and the subtitle file in last example is accompanied with, "Hello!" is displayed for one second. The software the MicroDVD Player expects the subtitle file to begin with the tag, and end with the tag .