Types and Values

Description

Parses timed text subtitle files described using Timed Text Markup Language (TTML). Currently, only the EBU-TT-D profile of TTML, designed for distribution of subtitles over IP, is supported.

The parser outputs a GstBuffer for each scene in the input TTML file, a scene being a period of time during which a static set of subtitles should be visible. The parser places each text element within a scene into its own GstMemory within the scene's buffer, and attaches metadata to the buffer describing the styling and layout associated with all the contained text elements. A downstream renderer element uses this information to correctly render the text on top of video frames.

1

gst-launch-1.0 filesrc location=<media file location> ! video/quicktime ! qtdemux name=q ttmlrender name=r q. ! queue ! h264parse ! avdec_h264 ! autovideoconvert ! r.video_sink filesrc location=<subtitle file location> blocksize=16777216 ! queue ! ttmlparse ! r.text_sink r. ! ximagesink q. ! queue ! aacparse ! avdec_aac ! audioconvert ! alsasink

Functions

Types and Values

struct GstTtmlParse {
  GstElement element;

  GstPad *sinkpad, *srcpad;

  /* contains the input in the input encoding */
  GstAdapter *adapter;
  /* contains the UTF-8 decoded input */
  GString *textbuf;

  /* seek */
  guint64 offset;

  /* Segment */
  GstSegment    segment;
  gboolean      need_segment;

  gboolean valid_utf8;
  gchar   *detected_encoding;
  gchar   *encoding;

  gboolean first_buffer;
};