xref: /aosp_15_r20/external/exoplayer/tree_8e57d3715f9092d5ec54ebe2e538f34bfcc34479/docs/drm.md (revision 30877f796caf59d855b10b687a5d6b3918d765cb)
1---
2title: Digital rights management
3---
4
5ExoPlayer uses Android's [`MediaDrm`][] API to support DRM protected playbacks.
6The minimum Android versions required for different supported DRM schemes, along
7with the streaming formats for which they're supported, are:
8
9| DRM scheme | Android version number | Android API level | Supported formats |
10|---------|:------------:|:------------:|:---------------------|
11| Widevine "cenc" | 4.4 | 19 | DASH, HLS (FMP4 only) |
12| Widevine "cbcs" | 7.1 | 25 | DASH, HLS (FMP4 only) |
13| ClearKey "cenc" | 5.0 | 21 | DASH |
14| PlayReady SL2000 "cenc" | AndroidTV | AndroidTV | DASH, SmoothStreaming, HLS (FMP4 only) |
15
16In order to play DRM protected content with ExoPlayer, the UUID of the DRM
17system and the license server URI should be specified
18[when building a media item]({{ site.baseurl }}/media-items.html#protected-content).
19The player will then use these properties to build a default implementation of
20`DrmSessionManager`, called `DefaultDrmSessionManager`, that's suitable for most
21use cases. For some use cases additional DRM properties may be necessary, as
22outlined in the sections below.
23
24### Key rotation ###
25
26To play streams with rotating keys, pass `true` to
27`MediaItem.DrmConfiguration.Builder.setMultiSession` when building the media
28item.
29
30### Multi-key content ###
31
32Multi-key content consists of multiple streams, where some streams use different
33keys than others. Multi-key content can be played in one of two ways, depending
34on how the license server is configured.
35
36##### Case 1: License server responds with all keys for the content #####
37
38In this case, the license server is configured so that when it receives a
39request for one key, it responds with all keys for the content. This case is
40handled by ExoPlayer without the need for any special configuration. Adaptation
41between streams (e.g. SD and HD video) is seamless even if they use different
42keys.
43
44Where possible, we recommend configuring your license server to behave in this
45way. It's the most efficient and robust way to support playback of multikey
46content, because it doesn't require the client to make multiple license requests
47to access the different streams.
48
49##### Case 2: License server responds with requested key only #####
50
51In this case, the license server is configured to respond with only the key
52specified in the request. Multi-key content can be played with this license
53server configuration by passing `true` to
54`MediaItem.DrmConfiguration.Builder.setMultiSession` when building the media
55item.
56
57We do not recommend configuring your license server to behave in this way. It
58requires extra license requests to play multi-key content, which is less
59efficient and robust than the alternative described above.
60
61### Offline keys ###
62
63An offline key set can be loaded by passing the key set ID to
64`MediaItem.DrmConfiguration.Builder.setKeySetId` when building the media item.
65This allows playback using the keys stored in the offline key set with the
66specified ID.
67
68{% include known-issue-box.html issue-id="3872" description="Only one offline
69key set can be specified per playback. As a result, offline playback of
70multi-key content is currently supported only when the license server is
71configured as described in Case 1 above." %}
72
73### DRM sessions for clear content ###
74
75Use of placeholder `DrmSessions` allows `ExoPlayer` to use the same decoders for
76clear content as are used when playing encrypted content. When media contains
77both clear and encrypted sections, you may want to use placeholder `DrmSessions`
78to avoid re-creation of decoders when transitions between clear and encrypted
79sections occur. Use of placeholder `DrmSessions` for audio and video tracks can
80be enabled by passing `true` to
81`MediaItem.DrmConfiguration.Builder.forceSessionsForAudioAndVideoTracks` when
82building the media item.
83
84### Using a custom DrmSessionManager ###
85
86If an app wants to customise the `DrmSessionManager` used for playback, they can
87implement a `DrmSessionManagerProvider` and pass this to the
88`MediaSource.Factory` which is [used when building the player]. The provider can
89choose whether to instantiate a new manager instance each time or not. To always
90use the same instance:
91
92~~~
93DrmSessionManager customDrmSessionManager =
94    new CustomDrmSessionManager(/* ... */);
95// Pass a drm session manager provider to the media source factory.
96MediaSource.Factory mediaSourceFactory =
97    new DefaultMediaSourceFactory(dataSourceFactory)
98        .setDrmSessionManagerProvider(mediaItem -> customDrmSessionManager);
99~~~
100{: .language-java}
101
102### Improving playback performance ###
103
104If you're experiencing video stuttering on a device running Android 6 to 11 when
105playing DRM protected content, you can try [enabling asynchronous buffer
106queueing].
107
108[main demo app]: {{ site.release_v2 }}/demos/main
109[`MediaDrm`]: {{ site.android_sdk }}/android/media/MediaDrm.html
110[used when building the player]: {{ site.baseurl }}/media-sources.html#customizing-media-source-creation
111[enabling asynchronous buffer queueing]: {{ site.baseurl }}/customization.html#enabling-asynchronous-buffer-queueing
112