Exoplayer does not play MPEG-DASH + PlayReady contents.

[from-unknown]

Description

I tried to play MPEG-DASH + PlayReady (actually it was a common encryption media - playready and widevine modular) contents and found that exoplayer could not play it.

Reproduce link

Not available now - I will try to create one if needed.
Manifest file is nearly like this.
Big Buck Bunny

Device

Nexus player (6.1)
Android TV - Sony Bravia (5.1.1)

Possible solution

While debugging this problem, I found that exoplayer did not parse mspr:pro tag in manifest file.
Looking at smooth streaming code, I added code below and then contents played fine.

code (exoplayer 2.X):
DashManifestParser.java

protected SchemeData parseContentProtection(XmlPullParser xpp) throws XmlPullParserException,
      IOException {
    String schemeIdUri = xpp.getAttributeValue(null, "schemeIdUri"); // Added
    byte[] data = null;
    UUID uuid = null;
    boolean seenPsshElement = false;
    boolean requiresSecureDecoder = false;
    do {
      xpp.next();
      // The cenc:pssh element is defined in 23001-7:2015.
      if (XmlPullParserUtil.isStartTag(xpp, "cenc:pssh") && xpp.next() == XmlPullParser.TEXT) {
        seenPsshElement = true;
        data = Base64.decode(xpp.getText(), Base64.DEFAULT);
        uuid = PsshAtomUtil.parseUuid(data);
      } else if (XmlPullParserUtil.isStartTag(xpp, "widevine:license")) {
        String robustnessLevel = xpp.getAttributeValue(null, "robustness_level");
        requiresSecureDecoder = robustnessLevel != null && robustnessLevel.startsWith("HW");
      // ----- Add start -----
      } else if (ParserUtil.isStartTag(xpp, "mspr:pro") && xpp.next() == XmlPullParser.TEXT) {
        seenPsshElement = true;
        uuid = UUID.fromString(schemeIdUri.split(":")[2]);
        data = new SchemeInitData(MimeTypes.VIDEO_MP4,
                PsshAtomUtil.buildPsshAtom(uuid,Base64.decode(xpp.getText(), Base64.DEFAULT)));
      }
      // ----- Add end ----- 
    } while (!XmlPullParserUtil.isEndTag(xpp, "ContentProtection"));
    if (!seenPsshElement) {
      return null;
    } else if (uuid != null) {
      return new SchemeData(uuid, MimeTypes.VIDEO_MP4, data, requiresSecureDecoder);
    } else {
      Log.w(TAG, "Skipped unsupported ContentProtection element");
      return null;
    }
}

code (exoplayer 1.X):
MediaPresentationDescriptionParser.java

  protected ContentProtection parseContentProtection(XmlPullParser xpp)
      throws XmlPullParserException, IOException {
    String schemeIdUri = xpp.getAttributeValue(null, "schemeIdUri");
    UUID uuid = null;
    SchemeInitData data = null;
    boolean seenPsshElement = false;
    do {
      xpp.next();
      // The cenc:pssh element is defined in 23001-7:2015.
      if (ParserUtil.isStartTag(xpp, "cenc:pssh") && xpp.next() == XmlPullParser.TEXT) {
        seenPsshElement = true;
        data = new SchemeInitData(MimeTypes.VIDEO_MP4,
            Base64.decode(xpp.getText(), Base64.DEFAULT));
        uuid = PsshAtomUtil.parseUuid(data.data);
      }
      // ----- Add start -----
      if (ParserUtil.isStartTag(xpp, "mspr:pro") && xpp.next() == XmlPullParser.TEXT) {
        seenPsshElement = true;
        uuid = UUID.fromString(schemeIdUri.split(":")[2]);
        data = new SchemeInitData(MimeTypes.VIDEO_MP4,
                PsshAtomUtil.buildPsshAtom(uuid,Base64.decode(xpp.getText(), Base64.DEFAULT)));
      }
      // ----- Add end ----- 
    } while (!ParserUtil.isEndTag(xpp, "ContentProtection"));
    if (seenPsshElement && uuid == null) {
      Log.w(TAG, "Skipped unsupported ContentProtection element");
      return null;
    }
    return buildContentProtection(schemeIdUri, uuid, data);
  }

I am not sure that this code is good enough, but at least works at my envelopment.
I hope this code helps solve this issue.

[ojw28]

Thanks for reporting this. For the sample manifest I'd expect playback to work due to the presence of cenc:pssh elements. It shouldn't be necessary to look at the mspr:pro elements. According to Microsoft's doc:

In the case of PlayReady, a PlayReady Header Object (PRO) [PRHEADER] can be contained in a
cenc:pssh element, an mspr:pro element, or a ‘pssh’ box to enable license acquisition. The
mspr:pro element is defined by Microsoft PlayReady, and includes only the PRO [PRHEADER]
information, not the box structure included in ‘pssh’ and cenc:pssh. Including both mspr:pro
and cenc:pssh will enable old players including a player based on Silverlight, and new players
including web pages using script to play protected DASH presentations on HTML5 browsers.

Which suggests that "new players" typically look at the cenc:pssh elements only. Could you clarify whether your manifest is missing cenc:pssh elements, and if so why? I think including one is the correct thing to do. If your manifest includes cenc:pssh elements then I think something else is wrong. There's no particular reason why we can't parse mspr:pro elements as well if necessary, but I'd like to make sure we understand exactly what's going on fiest.

[from-unknown]

Thank you for replying and information, now I understand more about this problem.
I checked manifest file and found that there is a no cenc:pssh element for PlayReady.

Currently I am using bento4 to make a MPEG-DASH file and generated file only have mspr:pro element and no cenc:pssh element for PlayReady.
I think bento4 should have a option to generate cenc:pssh element.
I'm going to check if bento4 is able to do it.

[ojw28]

If they don't have an option, you should probably request that they add one (they should probably be including both cenc:pssh and mspr:pro by default as suggested by Microsoft's doc for compatibility with both old and new players.

[ojw28]

The change ref'd above adds support for the mspr:pro element in V2, although I agree they should be including cenc:pssh as well regardless. We have no plans to backport.

[from-unknown]

Sorry for not replying soon.

First of all, thank you for supporting mspr:pro element.
As far as I read bento4's code, they do not support cenc:pssh.
I'll keep watching bento4.

If you don't mind, would you answer these questions?

• why do not backport mspr:pro element support?
• if any suggestions for code which I shared code for exo 1.X, I would like to know

[ojw28]

We're pretty much back-porting bug fixes only to V1. This is not a bug fix. There's also not much demand (this is the only issue requesting support for the element), should be fixed on the serving side anyway (by including a cenc:pssh element), and can be resolved by moving to V2.

[from-unknown]

Ok, I understand.
Thank you for your answer.