18175ca9b2
As packet duration is not stored inherently in MPEG4 containers, subtitles have their duration expressed by storing an additional empty packet with a pts matching the desired end time of the real subtitle. Additionally, it is generally expected that all streams start at time = 0, so an empty packet needs to be inserted at the beginning of the stream, before the first real subtitle. Unfortunately, ffmpeg lacks a proper way to express that a subtitle might map to multiple packets, so the muxer is the only place we can handle this. Signed-off-by: Philip Langdale <philipl@overt.org>
FFmpeg README ------------- 1) Documentation ---------------- * Read the documentation in the doc/ directory in git. You can also view it online at http://ffmpeg.org/documentation.html 2) Licensing ------------ * See the LICENSE file. 3) Build and Install -------------------- * See the INSTALL file.