What is an MPD file?

Question

In the context of DASH (dynamic adaptive streaming over HTTP), what exactly is an MPD file?

It's format is formally specified? If so, where is it available?

What role does it play in the context for viewing encrypted media?

(An example file with descriptive comments concerning what the file's respective fields are and what they do, would be greatly appreciated, preferably in a manner that is more accessible and less terse than a formal specification).

Solution 1

The MPD is a description of the resources forming a streaming service, that a DASH client uses to determine which assets to request in order to perform adaptive streaming of the content.

The MPD is formally defined in ISO/IEC 23009-1, which is available electronically, currently without payment, at https://www.iso.org/standard/65274.html - click on the link on that page to download a PDF.

When content is encrypted, the MPD contains ContentProtection elements which include protection scheme-specific information describing the scheme in question and possibly some initialisation data for the scheme, allowing the player to determine whether it can present the media.

Solution 2

MPD files denotes the media presentation description. It is a manifest file for MPEG DASH streaming. This manifest files contains various information and parameter for the video streaming. these parameters and information is codec, ABR and resolution of the video. There are many more things which a manifest file have. I refer you to read what is manifest file first then after you will get to know what it is. read it, What Is Manifest File ?

there are various other kinds of manifest files also available for apple and MSS which you will find easily in above link thanks !!!.

Comments

[Ladislav Mrnka]

Small correction - when content is encrypted, MPD may contain ContentProtection elements. Encryption may be signaled directly from the stream by PSSH box.