You can use the captioning features in Microsoft Expression Encoder to work with captions that range from those that you embed in the header of a file, or in the stream, to those that are formatted and styled, and that appear in multiple languages in DFXP sidecar files. Expression Encoder can import DFXP, SAMI, SRT, SUB, and LRC caption files. Depending on the caption tool that you use, you have a choice of either creating your captions and then, on encoding, embedding them in the file header or in the bit stream, or exporting your captions in a separate file that the media source references. You can work with captions in both the Script Commands and Text panels, and you have several options for creating, importing, and exporting those captions:
You can create captions from scratch in the Script Commands panel. Then, you can choose to either export them as DFXP sidecar files that you can use for Microsoft Silverlight playback, or, on encoding, embed them in the stream, in the header, depending on your output format.
In the Text panel, you can import media files that reference existing DFXP, SAMI, SRT, SUB, and LRC files. You can then combine the media and the caption files, and output them all into a single Silverlight package. Expression Encoder will preserve the format and styling of your original DFXP files and provide uniform formatting for your SAMI, SRT, SUB, and LRC files.