Some video players like VLC would have the option of rendering subtitles from an external file (.srt or .sub) on videos during playback. However, many embedded players, such as Xbox 360, may not have that kind of options. In such kind of case we may need to embed the subtitles in the video track, so we can burn videos with .srt or .sub files to DVD for DVD Player on Mac.

After extracting the tracks or having the video and subtitle files separated already (such as .avi and .srt file ), you can recombine them into an AVI container with subtitles embedded by using ffmpegX as following.

More detail about : How to Burn Videos and Subtitle Files (SRT,Sub )to DVD on Mac ?