ExoPlayer is an open source, application level media player built on top of Android’s low level media APIs (Mediacodec and MediaExtractor). Google is already using it for Youtube and Movies app. It supports DASH, Smooth Streaming and HLS protocols.

1. ExoPlayer for Application
Developers
Google Developers Summit - April 28
Hassan Abid - GDE

2. Contents
● Media Playback in Android
● ExoPlayer Overview
● Adaptive Media Playback Protocols and Demo
● Content Protection
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3. Terms
DASH : Dynamic Adaptive Streaming over HTTP
HLS : Http Live Streaming
DRM : Digital Rights Management
MPD : Media Presentation Description
ABR : Adaptive Bitrate Streaming
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4. Media Playbacks in Android
● VideoView [link]
● MediaPlayer & SurfaceView [link]
● ExoPlayer [link]
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5. It supports features not currently provided by MediaPlayer,
including DASH, SmoothStreaming and Common
Encryption.
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ExoPlayer is an open source, application level media player
built on top of Android’s low level media APIs (Mediacodec
and MediaExtractor). Google is already using it for Youtube
and Movies app

6. Pros
● Supports DASH,HLS, Smooth-Streaming …
● DRM protected content
● Customizable
● Easily Updatable
● Few device specific issues
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7. Cons
● ExoPlayer’s standard audio and video components rely on
Android’s MediaCodec API, which was released in Android
4.1 Jelly Bean (API level 16). Hence they do not work on
earlier versions of Android.
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8. Component Diagram
FrameworkSampleSource
ExoPlayer (Application Level)
Video/Audio/Text TrackRenderers
Media CodecMedia Extractor
Android Framework
BufferingNetworking Extraction Decoding
Audio Track
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Rendering

9. Interfaces
● TrackRenderer
○ MediaCodecVideoTrackRenderer
○ MediaCodecAudioTrackRenderer
○ TextTrackRenderer
● SampleSource
○ ExtractorSampleSource (Mp4)
○ ChunkSampleSource (Dash, Smooth Streaming)
○ HlsSampleSource (HLS)
● DataSource
○ DefaultUriDataSource
○ AssetDataSource
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10. Usage -MP4
DefaultUriDataSource ExtractorSampleSource
Mp4Extractor
MediaCodecVideoTrackRenderer
MediaCodecAudioTrackRenderer
ExoPlayer - MP4
Mediacodec AudioTrack
Decoding Rendering
Android Framework
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11. Execution Flow
ExoPlayerImplInternal
MediaCodecAudioTrackRenderer
MediaCodecVideoTrackRenderer
SampleSource for
Audio Track
SampleSource for
Video Track
MediaCodec
AudioTrack
Time Source
1:doSomeWork()
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2: readData() 3: queueInputBuffer()
4: dequeOutputBuffer()
5: handleBuffer()
6: doSomeWork()
7: getCurrentPositionUS()
8: readData()
9: decode & render()

12. DEMO
Traditional MediaPlayback (ExtractorRendererBuilder)
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13. 13
Code (ExtractorRendererBuilder)

14. Adaptive Media Playbacks or ABR
● Adaptive bitrate streaming over HTTP
● Accommodate changing network conditions
● No special firewalls, proxies, or cache is required
● Efficient and cost-effective
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15. Adaptive Media Playbacks (Example)
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16. Adaptive Media Playbacks (Protocols)
● Dynamic Adaptive Streaming over HTTP (DASH)
○ Mpeg
● Smooth Streaming
○ Microsoft
● HTTP Live Streaming (HLS)
○ Apple
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17. DASH
● First major trial started in 2012 London Olympics
● How it works? [ref]
HTTP Server
segment
segment
segment
segment
segment
segment
segment
segment
segment
segment
segment
segment
segment
segment
segment
segment
MPD
Dash Client
HTTP ClientHTTP/1.1
Media
Player
Control Heuristics
MPD Delivery MPD Parser
Segment
Parser
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1
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18. MPD [ref]
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19. DASH Object Model
DefaultUriDataSource DashChunkSource
FixedEvaluator
MediaCodecVideoTrackRenderer
ExoPlayer - Dash
Mediacodec AudioTrack
Decoding Rendering
DefaultUriDataSource DashChunkSource
AdaptiveEvaluator
ChunkSampleSource MediaCodecAudioTrackRenderer
DefaultLoadControl
ChunkSampleSource
Android Framework
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20. DEMO
DASH MediaPlayback (DashRendererBuilder)
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21. HLS
● Developed by Apple
● How it works? [ref]
Distribution Client
HTTP/1.1
Index
file (.
m3u8) .ts
.ts
.ts
.ts
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22. HLS Index File .M3U8
#EXT-X-VERSION:3
#EXTM3U
#EXT-X-TARGETDURATION:10
#EXT-X-MEDIA-SEQUENCE:1
# Old-style integer duration; avoid for newer clients.
#EXTINF:10,
http://media.example.com/segment0.ts
# New-style floating-point duration; use for modern clients.
#EXTINF:10.0,
http://media.example.com/segment1.ts
#EXTINF:9.5,
http://media.example.com/segment2.ts
#EXT-X-ENDLIST
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23. HLS Stream Alternates
Index
file
Alternate
-A
Index file
Alternate
- B
Index file
Alternate
- C
Index file
.ts
.ts
.ts
.ts
.ts
.ts
.ts
.ts
.ts
.ts
.ts
.ts
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24. 24
HLS advance index file

25. HLS Object Model
DefaultUriDataSource HLSChunkSource MediaCodecVideoTrackRenderer
MediaCodecAudioTrackRenderer
ExoPlayer - HLS
Mediacodec AudioTrack
Decoding Rendering
HLSSampleSource
Android Framework
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FormatEvaluator LoadControl

26. DEMO
HLS MediaPlayback (HlsRendererBuilder)
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27. Customization
● TrackRenderer
○ Example : TextTrackRenderer
● Extractor
● SampleSource
● FormatEvaluator
● DataSource
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28. Customization Example
CacheDataSource DashChunkSource
FixedEvaluator
MediaCodecVideoTrackRenderer
ExoPlayer - Dash
Mediacodec AudioTrack
Decoding Rendering
CacheDataSource DashChunkSource
AdaptiveEvaluator
ChunkSampleSource MediaCodecAudioTrackRenderer
DefaultLoadControl
ChunkSampleSource
Android Framework
DefaultUriDataSource
DefaultUriDataSource
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29. Digital Rights Management
Microsoft PlayReady Google Widevine
Fairplay (Apple) Adobe PrimeTime
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30. DEMO
WideVine DRM
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31. Digital Rights Management (ExoPlayer)
● DrmSessionManager
○ StreamingDrmSessionManager
○ On Android 4.3 (18) and higher
● WideVine DRM
○ DASH
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32. Conclusions
● ExoPlayer is an application level media player which can
be easily updated and extended by developers
● It is Open Source
● Start with demo code here
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33. Applications using ExoPlayer
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34. Helpful Links
● ExoPlayer Tutorial Video
● DASH, HLS encoder - Bento4
● Apple’s HLS Tools [link]
● Shaka Player for Web [link]
● dash.js [link]
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35. Thank You!
Sample Code : https://github.com/hassanabidpk/ExoPlayerSample
Contact : hassanabidpk89@gmail.com
Web : http://hassanabid.com
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