Widevine and MPEG-DASH - offline playback

Question

I have created an Android application which is capable of playing movies, which are protected with DRM (Widevine Modular). Video are in MPEG-DASH standard. In case, that device is online, everything works fine.

Now I need to add feature for playing video in offline mode. The problem is that I do not know how can I download some file(s) for offline playback. Everything what I have is .mpd file, which contains structured data.

How can I get some file(s) for download from this manifest .mpd file? There are no direct links to some video. I see some chunk, which looks like this:

media="chunk_ctvideo_cfm4s_rid$RepresentationID$_cs$Time$_w1003607280_qaWQ9QVBsSUxIMUpaRnVfdfdfkstMDImYXdsgdreaW9pbmRleD0w_mpd.m4s

I do not know if it is useful for me, but there is nothing more "noticeable" in the manifest file.

You need to post more information such as your mpd for detailed advice as there are a number of variants. You can most definitely get the chunks based on the manifest. A good starting place is the DASH spec — Andrew

Andrew Andrew · Accepted Answer · 2015-10-26T21:05:15

For an example of code that processes a manifest and downloads the media chunks have a look here: https://github.com/axiomatic-systems/Bento4/blob/master/Source/Python/utils/mp4-dash-clone.py

Of particular interest you may find the ProcessUrlTemplate which shows how to pass the media elements to get a URL for a chunk

Widevine and MPEG-DASH - offline playback

1 Answers