Input/Output Filters are filter commands executed when opening or saving files.
File Pattern: A glob pattern used to automatically select filters in the Open/Save File dialog. When a file that matches a file pattern is selected, the filter is automatically applied.
Default Extension: The default file extension is automatically added to a file name when a filter is selected in the "Save File As" dialog.
Input Filter Command: The command line executed when a filter is selected in the Open File dialog and the file is opened. The command receives the file content as input, and a document with the command's output is opened.
Output Filter Command: The command line executed when a file is saved and a filter was selected, either in the "Save File As" dialog or previously when the document was opened with a filter. The command receives the document content as input, and the output of the command is written to the file.