ElephantsDreamHLS

Script and manifest files to create an HLS program containing the Elephants Dream video with captions, subtitles, and audio description.

Works on macOS with iTerm2 shell.

To build the files

Run:

ed.sh

To clean up all created files, run:

clean.sh

Prerequisites

The following tools are needed (some using Homebrew):

bash
wget
ffmpeg
sed
cat

And from Apple:

mediasubtitlesegmenter
mediastreamvalidator
hlsreport.py

TODO

• Meet the Apple HLS Authoring Specification for Apple Devices
• The audio description text (.vtt) track is marked in the master playlist file as having "public.accessibility.describes-video" CHARACTERISTICS. This value is not valid for a SUBTITLES track (only for an AUDIO track), and causes a validation violation, but there is no valid way to mark a text track as the equivalent of HTML kind="descriptions" in HLS.