HLS specific stream descriptor fields

hls_name:Used for HLS audio to set the NAME attribute for EXT-X-MEDIA. Defaults to the base of the playlist name.
hls_group_id:Used for HLS audio to set the GROUP-ID attribute for EXT-X-MEDIA. Defaults to ‘audio’ if not specified.
playlist_name:The HLS playlist file to create. Usually ends with ‘.m3u8’, and is relative to hls_master_playlist_output (see below). If unspecified, defaults to something of the form ‘stream_0.m3u8’, ‘stream_1.m3u8’, ‘stream_2.m3u8’, etc.
iframe_playlist_name:
 The optional HLS I-Frames only playlist file to create. Usually ends with ‘.m3u8’, and is relative to hls_master_playlist_output (see below). Should only be set for video streams. If unspecified, no I-Frames only playlist is created.