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Media streaming on Android @droidkaigi 2018

TakuSemba
February 08, 2018

Media streaming on Android @droidkaigi 2018

TakuSemba

February 08, 2018
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  1. Media streaming
    on Android
    TakuSemba
    CyberAgent.Inc

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  2. @takusemba
    https://github.com/TakuSemba

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  3. Player

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  4. API level 1 API level 14
    Simple use cases Advanced use cases
    Black Box Customizable
    MediaPlayer ExoPlayer

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  5. ExoPlayer
    dependencies {
    implementation ‘com.google.android.exoplayer:exoplayer:x.x.x’
    }

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  6. ExoPlayer
    dependencies {
    implementation ‘com.google.android.exoplayer:exoplayer-core:x.x.x’
    implementation ‘com.google.android.exoplayer:exoplayer-ui:x.x.x’
    implementation ‘com.google.android.exoplayer:exoplayer-hls:x.x.x’
    }

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  7. ExoPlayer
    dependencies {
    implementation ‘com.google.android.exoplayer:exoplayer-core:x.x.x’
    implementation ‘com.google.android.exoplayer:exoplayer-ui:x.x.x’
    implementation ‘com.google.android.exoplayer:exoplayer-hls:x.x.x’
    implementation ‘com.google.android.exoplayer:extension-okhttp:x.x.x’
    }

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  8. Streaming

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  9. Streaming
    HTTP video

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  10. Streaming
    video

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  11. Streaming
    1min 1sec × 60files
    video .mp4
    .mp4
    video

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  12. Streaming
    time
    video1 video2 video3 video4

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  13. Streaming
    time
    video1 video2 video3 video4

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  14. time
    Streaming
    video1 video2 video3 video4
    video1

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  15. Streaming
    time
    video1 video2 video3 video4
    video1 video2

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  16. Streaming
    time
    video1 video2 video3 video4
    video1 video2 video3

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  17. time
    video1 video2 video3 video4
    Streaming
    video1 video2 video3 video4

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  18. Streaming

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  19. 1 pixel = 24 bits (1byte for red, blue, green)
    Streaming
    1 pixel

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  20. 1 pixel = 24 bits (1byte for red, blue, green)
    1 frame = 49m bits (1080px * 1920px * 24bits)
    Streaming
    1 frame

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  21. 1 pixel = 24 bits (1byte for red, blue, green)
    1 frame = 49m bits (1080px * 1920px * 24bits)
    1 second = 1492m bits (30fps * 49m bits)
    Streaming
    1 second

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  22. 1 pixel = 24 bits (1byte for red, blue, green)
    1 frame = 49m bits (1080px * 1920px * 24bits)
    1 second = 1492m bits (30fps * 49m bits)
    1492m bits
    Streaming
    1 second

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  23. 1 pixel = 24 bits (1byte for red, blue, green)
    1 frame = 49m bits (1080px * 1920px * 24bits)
    1 second = 1492m bits (30fps * 49m bits)
    1492m bits > 60m bps (4G LTE)
    Streaming
    1 second

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  24. 1 pixel = 24 bits (1byte for red, blue, green)
    1 frame = 49m bits (1080px * 1920px * 24bits)
    1 second = 1492m bits (30fps * 49m bits)
    1492m bits > 60m bps (4G LTE)
    codec (h264)
    Streaming
    1 second

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  25. 1 pixel = 24 bits (1byte for red, blue, green)
    1 frame = 49m bits (1080px * 1920px * 24bits)
    1 second = 1492m bits (30fps * 49m bits)
    1492m bits > 60m bps (4G LTE)
    14.92m bits < 60m bps (4G LTE)
    codec (h264)
    Streaming
    1 second

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  26. Resize This Window
    Resize This Window
    https://developer.android.com/guide/topics/media/media-formats.html

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  27. HLS

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  28. master playlist media playlists ts files
    .m3u8 .mp4
    .mp4
    .m3u8 .mp4
    .mp4
    .ts

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  29. master playlist media playlists ts files
    .m3u8 .mp4
    .mp4
    .m3u8 .mp4
    .mp4
    .ts

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  30. client master playlist
    .m3u8

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  31. HTTP
    client master playlist
    .m3u8

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  32. Master Playlist
    #EXTM3U

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=300000

    http://mycompany.com/240p.m3u8

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=1400000

    http://mycompany.com/480p.m3u8



    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=2400000

    http://mycompany.com/720p.m3u8


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  33. Master Playlist
    #EXTM3U

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=300000

    http://mycompany.com/240p.m3u8

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=1400000

    http://mycompany.com/480p.m3u8



    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=2400000

    http://mycompany.com/720p.m3u8


    #EXTM3U

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  34. Master Playlist
    #EXTM3U

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=300000

    http://mycompany.com/240p.m3u8

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=1400000

    http://mycompany.com/480p.m3u8



    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=2400000

    http://mycompany.com/720p.m3u8


    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=300000

    http://mycompany.com/240p.m3u8

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  35. Master Playlist
    #EXTM3U

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=300000

    http://mycompany.com/240p.m3u8

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=1400000

    http://mycompany.com/480p.m3u8



    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=2400000

    http://mycompany.com/720p.m3u8


    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=300000

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  36. Master Playlist
    #EXTM3U

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=300000

    http://mycompany.com/240p.m3u8

    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=1400000

    http://mycompany.com/480p.m3u8



    #EXT-X-STREAM-INF:PROGRAM-ID=1, BANDWIDTH=2400000

    http://mycompany.com/720p.m3u8


    http://mycompany.com/240p.m3u8

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  37. master playlist media playlists ts files
    .m3u8 .mp4
    .mp4
    .m3u8 .mp4
    .mp4
    .ts

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  38. client
    480p
    240p
    720p
    HTTP
    .m3u8
    .m3u8
    .m3u8

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  39. Media Playlist
    #EXT-X-VERSION:3

    #EXTM3U

    #EXT-X-TARGETDURATION:10

    #EXT-X-MEDIA-SEQUENCE:1

    #EXTINF:10.0,

    http://media.example.com/segment1.ts

    #EXTINF:9.0,

    http://media.example.com/segment2.ts

    #EXTINF:7.5,

    http://media.example.com/segment3.ts

    #EXTINF:8.5,

    http://media.example.com/segment4.ts


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  40. Media Playlist
    #EXT-X-VERSION:3

    #EXTM3U

    #EXT-X-TARGETDURATION:10

    #EXT-X-MEDIA-SEQUENCE:1

    #EXTINF:10.0,

    http://media.example.com/segment1.ts

    #EXTINF:9.0,

    http://media.example.com/segment2.ts

    #EXTINF:7.5,

    http://media.example.com/segment3.ts

    #EXTINF:8.5,

    http://media.example.com/segment4.ts


    #EXTINF:10.0,

    http://media.example.com/segment1.ts

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  41. Media Playlist
    #EXT-X-VERSION:3

    #EXTM3U

    #EXT-X-TARGETDURATION:10

    #EXT-X-MEDIA-SEQUENCE:1

    #EXTINF:10.0,

    http://media.example.com/segment1.ts

    #EXTINF:9.0,

    http://media.example.com/segment2.ts

    #EXTINF:7.5,

    http://media.example.com/segment3.ts

    #EXTINF:8.5,

    http://media.example.com/segment4.ts


    #EXTINF:10.0,

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  42. Media Playlist
    #EXT-X-VERSION:3

    #EXTM3U

    #EXT-X-TARGETDURATION:10

    #EXT-X-MEDIA-SEQUENCE:1

    #EXTINF:10.0,

    http://media.example.com/segment1.ts

    #EXTINF:9.0,

    http://media.example.com/segment2.ts

    #EXTINF:7.5,

    http://media.example.com/segment3.ts

    #EXTINF:8.5,

    http://media.example.com/segment4.ts


    http://media.example.com/segment1.ts

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  43. Media Playlist
    #EXT-X-VERSION:3

    #EXTM3U

    #EXT-X-TARGETDURATION:10

    #EXT-X-MEDIA-SEQUENCE:1

    #EXTINF:10.0,

    http://media.example.com/segment1.ts

    #EXTINF:9.0,

    http://media.example.com/segment2.ts

    #EXTINF:7.5,

    http://media.example.com/segment3.ts

    #EXTINF:8.5,

    http://media.example.com/segment4.ts


    http://media.example.com/segment2.ts

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  44. Media Playlist
    #EXT-X-VERSION:3

    #EXTM3U

    #EXT-X-TARGETDURATION:10

    #EXT-X-MEDIA-SEQUENCE:1

    #EXTINF:10.0,

    http://media.example.com/segment1.ts

    #EXTINF:9.0,

    http://media.example.com/segment2.ts

    #EXTINF:7.5,

    http://media.example.com/segment3.ts

    #EXTINF:8.5,

    http://media.example.com/segment4.ts


    http://media.example.com/segment3.ts

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  45. master playlist media playlists ts files
    .m3u8 .mp4
    .mp4
    .m3u8 .mp4
    .mp4
    .ts

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  46. client
    480p
    240p
    720p
    HTTP
    .m3u8
    .m3u8
    .m3u8
    .mp4
    .mp4
    .ts
    .mp4
    .mp4
    .ts
    .mp4
    .mp4
    .ts

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  47. client
    480p
    240p
    720p
    HTTP
    .m3u8
    .m3u8
    .m3u8
    .mp4
    .mp4
    .ts
    .mp4
    .mp4
    .ts
    .mp4
    .mp4
    .ts

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  48. HTTP
    client
    480p
    240p
    720p
    .m3u8
    .m3u8
    .m3u8
    .mp4
    .mp4
    .ts
    .mp4
    .mp4
    .ts
    .mp4
    .mp4
    .ts

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  49. HTTP
    client
    480p
    240p
    720p
    .m3u8
    .m3u8
    .m3u8
    .mp4
    .mp4
    .ts
    .mp4
    .mp4
    .ts
    .mp4
    .mp4
    .ts

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  50. MPEG-DASH

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  51. MPD fragmented mp4 file Initialization file
    .mpd .mp4 .mp4

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  52. MPD fragmented mp4 file Initialization file
    .mpd .mp4 .mp4

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  53. MPD fragmented mp4 file Initialization file
    .mpd .mp4 .mp4

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  54. MP4
    ftyp: file type
    moov: header data
    mdat: audio or video data

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  55. ftyp: file type
    moof: header data
    sidx: index of moof + mdat
    Fragmented MP4
    mdat: audio or video data

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  56. Fragmented MP4
    fragmented mp4 segment files
    .mp4 .mp4
    .mp4
    .m4s

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  57. MPD fragmented mp4 file Initialization file
    .mpd .mp4 .mp4

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  58. MPD
    maxSegmentDuration="PT0H0M10.010S" profiles="urn:mpeg:dash:profile:isoff-on-demand:2011">

    subsegmentAlignment="true" subsegmentStartsWithSAP="1">
    startWithSAP="1" bandwidth="400823">
    400k.mp4









    output_audio_dashinit.mp4







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  59. MPD










    ɾlive or onDemand ?
    ɾresolution ?
    ɾbyte range or segment path

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  60. ExoPlayer

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  61. val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val dataSourceFactory = DefaultDataSourceFactory(context, "user-agent")

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true

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  62. val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val dataSourceFactory = DefaultDataSourceFactory(context, "user-agent")

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true
    val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )

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  63. val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val dataSourceFactory = DefaultDataSourceFactory(context, "user-agent")

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true
    val playerView = findViewById(R.id.player_view)
    playerView.player = player

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  64. val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val dataSourceFactory = DefaultDataSourceFactory(context, "user-agent")

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true
    val dataSourceFactory = DefaultDataSourceFactory(context, "user-agent")

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

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  65. val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val dataSourceFactory = DefaultDataSourceFactory(context, "user-agent")

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true
    player.prepare(mediaSource)

    player.playWhenReady = true

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  66. val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val dataSourceFactory = DefaultDataSourceFactory(context, "user-agent")

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true
    // clean up

    player.release()

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  67. val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val dataSourceFactory = DefaultDataSourceFactory(context, "user-agent")

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true

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  68. val player = ExoPlayerFactory.newSimpleInstance(…)
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val dataSourceFactory = DefaultDataSourceFactory(context, "user-agent")

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true

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  69. val player = ExoPlayerFactory.newSimpleInstance(…)
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val dataSourceFactory = DefaultDataSourceFactory(context, "user-agent")

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true

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  70. val player = ExoPlayerFactory.newSimpleInstance(…)
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val okHttpClient = OkHttpClient.Builder()
    .connectTimeout(10L, TimeUnit.SECONDS)
    .writeTimeout(10L, TimeUnit.SECONDS)
    .readTimeout(30L, TimeUnit.SECONDS)
    .build()
    val dataSourceFactory = DefaultDataSourceFactory(context, "user-agent")

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true

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  71. val player = ExoPlayerFactory.newSimpleInstance(…)
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val okHttpClient = OkHttpClient.Builder()
    .connectTimeout(10L, TimeUnit.SECONDS)
    .writeTimeout(10L, TimeUnit.SECONDS)
    .readTimeout(30L, TimeUnit.SECONDS)
    .build()
    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true

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  72. val player = ExoPlayerFactory.newSimpleInstance(…)
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val okHttpClient = OkHttpClient.Builder()
    .connectTimeout(10L, TimeUnit.SECONDS)
    .writeTimeout(10L, TimeUnit.SECONDS)
    .readTimeout(30L, TimeUnit.SECONDS)
    .build()
    val dataSourceFactory = OkHttpDataSourceFactory(okHttpClient, “user-agent”, null)

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true

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  73. val player = ExoPlayerFactory.newSimpleInstance(…)
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val okHttpClient = OkHttpClient(…)
    val dataSourceFactory = OkHttpDataSourceFactory(okHttpClient, “user-agent”, null)

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true

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  74. val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val okHttpClient = OkHttpClient(…)
    val dataSourceFactory = OkHttpDataSourceFactory(okHttpClient, “user-agent”, null)

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true

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  75. val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    val playerView = findViewById(R.id.player_view)

    playerView.player = player

    val okHttpClient = OkHttpClient(…)
    val dataSourceFactory = OkHttpDataSourceFactory(okHttpClient, “user-agent”, null)

    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)

    player.prepare(mediaSource)

    player.playWhenReady = true
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()

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  76. Renderer
    val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )

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  77. Renderer
    val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    DefaultRenderersFactory(context)

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  78. Renderer
    public class MyRenderer implements Renderer {
    // make your own renderer
    }

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  79. Renderer
    public class MyRenderer implements Renderer {
    // make your own renderer
    }
    DefaultRenderersFactory(..., MyRenderer())

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  80. TrackSelector
    val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )

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  81. TrackSelector
    val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    DefaultTrackSelector(),

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  82. TrackSelector
    val selector = DefaultTrackSelector()

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  83. TrackSelector
    val factory = AdaptiveTrackSelection.Factory(
    DefaultBandwidthMeter(),
    DEFAULT_MAX_INITIAL_BITRATE,
    DEFAULT_MIN_DURATION_FOR_QUALITY_INCREASE_MS,
    DEFAULT_MAX_DURATION_FOR_QUALITY_DECREASE_MS,
    DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
    DEFAULT_BANDWIDTH_FRACTION)

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  84. TrackSelector
    val factory = AdaptiveTrackSelection.Factory(
    DefaultBandwidthMeter(),
    DEFAULT_MAX_INITIAL_BITRATE,
    DEFAULT_MIN_DURATION_FOR_QUALITY_INCREASE_MS,
    DEFAULT_MAX_DURATION_FOR_QUALITY_DECREASE_MS,
    DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
    DEFAULT_BANDWIDTH_FRACTION)
    val selector = DefaultTrackSelector(factory)

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  85. TrackSelector
    val selector = DefaultTrackSelector(factory)
    val factory = AdaptiveTrackSelection.Factory(
    DefaultBandwidthMeter(),
    HIEST_BITRATE,
    DEFAULT_MIN_DURATION_FOR_QUALITY_INCREASE_MS,
    DEFAULT_MAX_DURATION_FOR_QUALITY_DECREASE_MS,
    DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
    DEFAULT_BANDWIDTH_FRACTION)

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  86. client
    480p
    240p
    720p
    HTTP
    .m3u8
    .m3u8
    .m3u8

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  87. client
    480p
    240p
    720p
    .m3u8
    .m3u8
    .m3u8
    HTTP

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  88. TrackSelector
    val selector = DefaultTrackSelector(factory)
    val factory = AdaptiveTrackSelection.Factory(
    DefaultBandwidthMeter(),
    DEFAULT_MAX_INITIAL_BITRATE,
    DEFAULT_MIN_DURATION_FOR_QUALITY_INCREASE_MS,
    DEFAULT_MAX_DURATION_FOR_QUALITY_DECREASE_MS,
    DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
    DEFAULT_BANDWIDTH_FRACTION)

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  89. TrackSelector
    val selector = DefaultTrackSelector(factory)
    val factory = AdaptiveTrackSelection.Factory(
    DefaultBandwidthMeter(),
    DEFAULT_MAX_INITIAL_BITRATE,
    DEFAULT_MIN_DURATION_FOR_QUALITY_INCREASE_MS,
    DEFAULT_MAX_DURATION_FOR_QUALITY_DECREASE_MS,
    DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
    DEFAULT_BANDWIDTH_FRACTION)
    DefaultBandwidthMeter(),

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  90. TrackSelector
    public final class DefaultBandwidthMeter implements BandwidthMeter, TransferListener {
    @Override public long getBitrateEstimate() {
    return currentBitrate;
    }
    @Override public void onTransferStart(Object source, DataSpec dataSpec) {
    }
    @Override public void onBytesTransferred(Object source, int bytesTransferred) {
    }
    @Override public void onTransferEnd(Object source) {
    }
    }

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  91. TrackSelector
    public final class DefaultBandwidthMeter implements BandwidthMeter, TransferListener {
    @Override public long getBitrateEstimate() {
    return currentBitrate;
    }
    @Override public void onTransferStart(Object source, DataSpec dataSpec) {
    }
    @Override public void onBytesTransferred(Object source, int bytesTransferred) {
    }
    @Override public void onTransferEnd(Object source) {
    }
    }
    @Override public long getBitrateEstimate() {
    return currentBitrate;
    }

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  92. TrackSelector
    public final class MyBandwidthMeter implements BandwidthMeter,
    TransferListener {
    @Override public long getBitrateEstimate() {
    return Math.min(currentBitrate, limitBitrate);
    }
    @Override public void onTransferStart(Object source, DataSpec dataSpec) {
    }
    @Override public void onBytesTransferred(Object source, int bytesTransferred) {
    }
    @Override public void onTransferEnd(Object source) {
    }
    }
    @Override public long getBitrateEstimate() {
    return Math.min(currentBitrate, limitBitrate);
    }
    MyBandwidthMeter

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  93. TrackSelector
    val selector = DefaultTrackSelector(factory)
    val factory = AdaptiveTrackSelection.Factory(
    MyBandwidthMeter(),
    DEFAULT_MAX_INITIAL_BITRATE,
    DEFAULT_MIN_DURATION_FOR_QUALITY_INCREASE_MS,
    DEFAULT_MAX_DURATION_FOR_QUALITY_DECREASE_MS,
    DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
    DEFAULT_BANDWIDTH_FRACTION)

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  94. TrackSelector
    val selector = DefaultTrackSelector(factory)
    val factory = AdaptiveTrackSelection.Factory(
    MyBandwidthMeter(),
    DEFAULT_MAX_INITIAL_BITRATE,
    DEFAULT_MIN_DURATION_FOR_QUALITY_INCREASE_MS,
    DEFAULT_MAX_DURATION_FOR_QUALITY_DECREASE_MS,
    DEFAULT_MIN_DURATION_TO_RETAIN_AFTER_DISCARD_MS,
    DEFAULT_BANDWIDTH_FRACTION)
    MyBandwidthMeter(),

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  95. client
    480p
    240p
    720p
    .m3u8
    .m3u8
    .m3u8
    HTTP

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  96. client
    480p
    240p
    720p
    .m3u8
    .m3u8
    .m3u8
    HTTP

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  97. TrackSelector
    public final class MyBandwidthMeter implements BandwidthMeter,
    TransferListener {
    @Override public long getBitrateEstimate() {
    return Math.max(currentBitrate, limitBitrate);
    }
    @Override public void onTransferStart(Object source, DataSpec dataSpec) {
    }
    @Override public void onBytesTransferred(Object source, int bytesTransferred) {
    }
    @Override public void onTransferEnd(Object source) {
    }
    }

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  98. TrackSelector
    public final class MyBandwidthMeter implements BandwidthMeter,
    TransferListener {
    @Override public long getBitrateEstimate() {
    return Math.max(currentBitrate, limitBitrate);
    }
    @Override public void onTransferStart(Object source, DataSpec dataSpec) {
    }
    @Override public void onBytesTransferred(Object source, int bytesTransferred) {
    }
    @Override public void onTransferEnd(Object source) {
    }
    }
    return Math.max(currentBitrate, limitBitrate);
    MyBandwidthMeter

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  99. client
    480p
    240p
    720p
    HTTP
    .m3u8
    .m3u8
    .m3u8

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  100. client
    480p
    240p
    720p
    HTTP
    .m3u8
    .m3u8
    .m3u8

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  101. LoadControl
    val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )

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  102. LoadControl
    val player = ExoPlayerFactory.newSimpleInstance(
    DefaultRenderersFactory(context),
    DefaultTrackSelector(),
    DefaultLoadControl()
    )
    DefaultLoadControl()

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  103. LoadControl
    val loadControl = DefaultLoadControl()

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  104. LoadControl
    val loadControl = DefaultLoadControl(
    DefaultAllocator(true, C.DEFAULT_BUFFER_SEGMENT_SIZE),
    DEFAULT_MIN_BUFFER_MS,
    DEFAULT_MAX_BUFFER_MS,
    DEFAULT_BUFFER_FOR_PLAYBACK_MS,
    DEFAULT_BUFFER_FOR_PLAYBACK_AFTER_REBUFFER_MS
    )

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  105. LoadControl
    val loadControl = DefaultLoadControl(
    DefaultAllocator(true, C.DEFAULT_BUFFER_SEGMENT_SIZE),
    DEFAULT_MIN_BUFFER_MS,
    DEFAULT_MAX_BUFFER_MS,
    DEFAULT_BUFFER_FOR_PLAYBACK_MS,
    DEFAULT_BUFFER_FOR_PLAYBACK_AFTER_REBUFFER_MS
    )
    DEFAULT_MIN_BUFFER_MS,
    DEFAULT_MAX_BUFFER_MS,
    DEFAULT_BUFFER_FOR_PLAYBACK_MS,
    DEFAULT_BUFFER_FOR_PLAYBACK_AFTER_REBUFFER_MS

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  106. MediaSource
    val mediaSource = HlsMediaSource(uri, dataSourceFactory, handler, null)
    player.prepare(mediaSource)

    player.playWhenReady = true

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  107. MediaSource
    val mediaSource = DashMediaSource(Uri, …)
    player.prepare(mediaSource)

    player.playWhenReady = true

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  108. MediaSource
    val mediaSource = ExtractorMediaSource(Uri, …)
    player.prepare(mediaSource)

    player.playWhenReady = true

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  109. MediaSource
    val firstSource = HlsMediaSource(firstUri, …)
    val secondSource = HlsMediaSource(secondUri, …)
    val mediaSource = ConcatenatingMediaSource(firstSource, secondSource)
    // play firstSource, then secondSource
    player.prepare(mediaSource)

    player.playWhenReady = true

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  110. Metadata

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  111. Metadata
    video

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  112. Metadata
    video
    createdAt?
    title? thumbnail?
    genre?

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  113. Metadata
    ɾID3 tag

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  114. Metadata
    ɾID3 tag
    .ts
    id = 1000
    place = droidkaigi

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  115. Metadata

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  116. Metadata
    class Logger : MetadataOutput {
    override fun onMetadata(metadata: Metadata) {
    (1..metadata.length())
    .map { metadata[it] }
    .filterIsInstance()
    .forEach {
    print("metadata: ${it.value}")
    }
    }
    } // metadata: id=1000,place=droidkaigi

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  117. Metadata
    ɾID3 tag
    ɾemsg box

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  118. Metadata
    ɾID3 tag
    id = 1000
    place = droidkaigi
    ɾemsg box .mp4

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  119. Metadata
    class Logger : MetadataOutput {
    override fun onMetadata(metadata: Metadata) {
    (1..metadata.length())
    .map { metadata[it] }
    .filterIsInstance()
    .forEach {
    print("metadata: ${it.value}")
    }
    }
    } // metadata: id=1000,place=droidkaigi

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  120. Publish

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  121. UDP TCP
    1:1 1:n
    low latency high latency
    WebRTC RTMP

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  122. RTMP
    RTMP
    client server

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  123. RTMP
    RTMP
    client server users
    RTMP

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  124. RTMP
    RTMP
    client server users
    HLS
    MPEG-DASH

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  125. RTMP
    ɾdeveloped by Adobe. not “open” protocol
    ɾRed5 started rtmp in 2005
    ɾWowza started rtmp in 2007
    ɾrtmpdump released in 2008
    ɾrtmp specification released 2012

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  126. RTMP
    “we will stop updating and distributing
    the Flash Player at the end of 2020”
    -Adobe

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  127. RTMP
    RTMP

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  128. RTMP
    RTMP

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  129. RTMP
    RTMP

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  130. RTMP
    RTMP

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  131. RTMP
    PRO
    CON
    ɾsmall header (basically 1, 4, 8, 12 bytes)
    ɾrealtime
    ɾdifficult to cache
    ɾno multiple resolutions

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  132. RTMP
    RTMP

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  133. RTMP
    RTMP RTMP

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  134. RTMP
    RTMP

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  135. RTMP
    dependencies {
    implementation ‘com.google.android.exoplayer:exoplayer-core:x.x.x’
    implementation ‘com.google.android.exoplayer:exoplayer-ui:x.x.x’
    implementation ‘com.google.android.exoplayer:extension-rtmp:x.x.x’
    }

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  136. val mediaSource = ExtractorMediaSource(

    Uri.parse("rtmp://xxx.xx.xx.xxx:1935/path/stream_name")

    RtmpDataSourceFactory(),

    DefaultExtractorsFactory(),

    null,

    null)
    player.prepare(mediaSource)

    player.playWhenReady = true

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  137. val mediaSource = ExtractorMediaSource(

    Uri.parse("rtmp://xxx.xx.xx.xxx:1935/path/stream_name")

    RtmpDataSourceFactory(),

    DefaultExtractorsFactory(),

    null,

    null)
    player.prepare(mediaSource)

    player.playWhenReady = true
    Uri.parse("rtmp://xxx.xx.xx.xxx:1935/path/stream_name")

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  138. val mediaSource = ExtractorMediaSource(

    Uri.parse("rtmp://xxx.xx.xx.xxx:1935/path/stream_name")

    RtmpDataSourceFactory(),

    DefaultExtractorsFactory(),

    null,

    null)
    player.prepare(mediaSource)

    player.playWhenReady = true
    RtmpDataSourceFactory(),

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  139. public final class RtmpDataSource implements DataSource {
    private RtmpClient rtmpClient;
    ...
    @Override
    public int read(byte[] buffer, int offset, int readLength) throws IOException {
    int bytesRead = rtmpClient.read(buffer, offset, readLength);
    ...
    return bytesRead;
    }
    ...
    }

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  140. public final class RtmpDataSource implements DataSource {
    private RtmpClient rtmpClient;
    ...
    @Override
    public int read(byte[] buffer, int offset, int readLength) throws IOException {
    int bytesRead = rtmpClient.read(buffer, offset, readLength);
    ...
    return bytesRead;
    }
    ...
    }
    private RtmpClient rtmpClient;
    rtmpClient.read(buffer, offset, readLength);

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  141. public class RtmpClient {



    public int read(byte[] data, int offset, int size) throws IOException {

    return nativeRead(data, offset, size, rtmpPointer);

    }

    private native int nativeRead(byte[] data, int offset, int size, long rtmpPointer)
    throws IOException



    }

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  142. public class RtmpClient {



    public int read(byte[] data, int offset, int size) throws IOException {

    return nativeRead(data, offset, size, rtmpPointer);

    }

    private native int nativeRead(byte[] data, int offset, int size, long rtmpPointer)
    throws IOException



    }
    private native int nativeRead(byte[] data, int offset, int size, long rtmpPointer)
    public class RtmpClient

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  143. RTMP
    RTMP

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  144. RTMP
    ɾcapture data
    ɾencode data
    ɾpublish data

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  145. RTMP
    ɾcapture data
    ɾencode data
    ɾpublish data

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  146. RTMP
    ɾcapture data
    ɾencode data
    ɾpublish data
    val audioRecord = AudioRecord(...)
    Audio Data

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  147. RTMP
    ɾcapture data
    ɾencode data
    ɾpublish data
    val audioRecord = AudioRecord(...)
    // camera2 API

    val manager : CameraManager

    manager.openCamera(...)
    // camera API

    val camera = Camera.(info)
    Audio Data
    Video Data

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  148. RTMP
    ɾcapture data
    ɾencode data
    ɾpublish data

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  149. RTMP
    // MediaCodec.java

    val encoder = MediaCodec(…)

    encoder.start()

    val inputBuffers = encoder.getInputBuffer(index)

    // or

    val surface = encoder.createInputSurface()

    // get encoded data

    val outputBuffers

    = encoder.getOutputBuffer(index)
    ɾcapture data
    ɾencode data
    ɾpublish data

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  150. RTMP
    // MediaCodec.java

    val encoder = MediaCodec(…)

    encoder.start()

    val inputBuffers = encoder.getInputBuffer(index)

    // or

    val surface = encoder.createInputSurface()

    // get encoded data

    val outputBuffers

    = encoder.getOutputBuffer(index)
    ɾcapture data
    ɾencode data
    ɾpublish data
    // MediaCodec.java

    val encoder = MediaCodec(…)

    encoder.start()

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  151. RTMP
    ɾcapture data
    ɾencode data
    ɾpublish data
    // MediaCodec.java

    val encoder = MediaCodec(…)

    encoder.start()

    val inputBuffers = encoder.getInputBuffer(index)

    // or

    val surface = encoder.createInputSurface()

    // get encoded data

    val outputBuffers

    = encoder.getOutputBuffer(index)
    val inputBuffers = encoder.getInputBuffer(index)

    // or

    val surface = encoder.createInputSurface()

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  152. RTMP
    ɾcapture data
    ɾencode data
    ɾpublish data
    // MediaCodec.java

    val encoder = MediaCodec(…)

    encoder.start()

    val inputBuffers = encoder.getInputBuffer(index)

    // or

    val surface = encoder.createInputSurface()

    // get encoded data

    val outputBuffers

    = encoder.getOutputBuffer(index)
    // get encoded data

    val outputBuffers

    = encoder.getOutputBuffer(index)

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  153. RTMP
    ɾcapture data
    ɾencode data
    ɾpublish data

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  154. RTMP
    // rtmpdump

    public native int writeVideo(

    byte[] data,

    int offset,

    int length,

    int timestamp

    )
    ɾcapture data
    ɾencode data
    ɾpublish data

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  155. RTMP
    // rtmpdump

    public native int writeVideo(

    byte[] data,

    int offset,

    int length,

    int timestamp

    )
    // Socket.java

    val socket = Socket(“192.xx.xx.xxx", 1935)

    val outputStream = DataOutputStream(…)

    outputStream.write(byteArray)
    ɾcapture data
    ɾencode data
    ɾpublish data

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  156. https://github.com/TakuSemba/RtmpPublisher

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  157. Demo

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  158. Demo
    RTMP
    Server
    HLS
    RTMP
    Publisher
    Player
    Player

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  159. Demo
    rtmp://160.16.54.236:1935/live/takusemba
    http://160.16.54.236/hls/takusemba.m3u8
    RTMP
    HLS

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  160. Media streaming
    on Android
    https://github.com/takusemba
    https://twitter.com/takusemba

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