Get the The Segment Index box (sidx) of a youtube video in json. The application would be if you wanted to use this with a video mediasource by requesting indivdual byteRange references from the SIDX and appending the buffer to the source.
It is promised with bluebird.
Please see the example.js for use.
You will need youtube-dl because sometimes, especially for copywrited content, youtube does not give the index ranges lightly, so we need to leverage this library to download the manifests.