本頁面由 Cloud Translation API 翻譯而成。

開始使用 IMA DAI SDK

您可以使用 IMA SDK 輕鬆將多媒體廣告整合至網站和應用程式。IMA SDK 可以從任何符合 VAST 規定的廣告伺服器請求廣告，並管理在應用程式中播放的廣告。使用 IMA DAI SDK 時，應用程式會向廣告和內容影片 (VOD 或直播內容) 發出串流請求。接著，SDK 會傳回合併的影片串流，因此您不必在應用程式中管理廣告和內容影片之間的切換。

選取感興趣的動態廣告解決方案

本指南將示範如何使用 Roku 的 IMA DAI SDK 播放 DAI 廣告連播放送功能直播或隨選串流。

IMA DAI 廣告連播放送總覽

使用 IMA DAI 實作 Pod 服務時，需要使用兩個主要的 SDK 元件，本指南會說明這兩個元件：

StreamRequest.createPodLiveStreamRequest()/StreamRequest.createPodVodStreamRequest()：建立物件，定義傳送至 Google 廣告伺服器的串流要求。這些要求會指定 Network Code，而 Pod Live ima.StreamRequest 也需要 Custom Asset Key，以及選用的 API 金鑰。
StreamManager：這個物件會處理影片串流與 IMA DAI SDK 之間的通訊，例如觸發追蹤連線偵測 (ping)，以及將串流事件轉送至發布商。

此外，您必須向資訊清單操控伺服器提出要求，以擷取要顯示的串流資訊清單。具體程序可能因影片技術合作夥伴 (VTP) 而異。

必要條件

請參閱相容性頁面，確認系統支援您要使用的用途。
下載 Roku 範例播放器程式碼。
將範例播放器程式碼部署至 Roku 裝置，驗證開發設定是否可正常運作。

播放影片

提供的範例影片播放器可播放內容影片。將範例播放器部署至 Roku 裝置，確保開發環境設定正確無誤。

將影片播放器轉換為 IMA DAI 串流播放器

請按照下列步驟實作串流播放器。

建立 Sdk.xml

在專案中新增一個名為 Sdk.xml 的 MainScene.xml 檔案，並加入以下範本：

Sdk.xml

<?xml version = "1.0" encoding = "utf-8" ?>

  <component name = "imasdk" extends = "Task">
  <interface>
  </interface>
  <script type = "text/brightscript">
  <![CDATA[
    ' Your code goes here.
  ]]>
  </script>
  </component>

您需要在本指南中編輯這兩個檔案 (MainScene.xml 和 Sdk.xml)。

載入 IMA DAI SDK 架構

如要載入架構，請在 manifest 和 Sdk.xml 中加入下列內容：

manifest

bs_libs_required=googleima3

Sdk.xml

<?xml version = "1.0" encoding = "utf-8" ?>

  <component name = "imasdk" extends = "Task">
  <interface>
  </interface>
  <script type = "text/brightscript">
  <![CDATA[
  Library "IMA3.brs"
  ]]>
  </script>
  </component>

初始化 IMA DAI SDK

載入 IMA 動態廣告插播串流的第一步，是載入並初始化 IMA DAI SDK。以下是初始化 IMA DAI SDK 指令碼的範例。

Sdk.xml

<?xml version="1.0" encoding="utf-8" ?>

  <component name="IMASDKTask" extends="Task">
  <interface>
    <field id="IMASDKInitialized" type="Boolean" />
    <field id="errors" type="stringarray" />
  </interface>
  <script type = "text/brightscript">
  <![CDATA[
    Library "IMA3.brs"
    sub init()
      m.top.functionName = "runThread"
    end sub

    sub runThread()
      if not m.top.IMASDKInitialized
        initializeIMASDK()
      end if
    end sub

    sub initializeIMASDK()
        if m.sdk = invalid
          m.sdk = New_IMASDK()
        end if
        m.top.IMASDKInitialized = true
    end sub
  ]]>
  </script>
  </component>

現在，請在 MainScene.xml 中啟動這項工作，並移除用於載入內容串流的呼叫。

MainScene.xml

<?xml version="1.0" encoding="utf-8" ?>

<component extends="Scene" initialFocus="myVideo" name="MainScene">
  <script type="text/brightscript">
  <![CDATA[
  function init()
    m.video = m.top.findNode("myVideo")
    m.video.notificationinterval = 1
    runIMASDKTask()
  end function

  function runIMASDKTask()
    m.IMASDKTask = createObject("roSGNode", "IMASDKTask")
    m.IMASDKTask.observeField("IMASDKInitialized", "handleIMASDKInitialized")
    m.IMASDKTask.observeField("errors", "handleIMASDKErrors")

    m.IMASDKTask.control = "RUN"
  end function

  sub handleIMASDKInitialized()

    ' Follow your manifest manipulator (VTP) documentation to register a user
    ' streaming session if needed.

  end sub

  sub handleIMASDKErrors(message as object)
    print "------ IMA DAI SDK failed  ------"
    if message <> invalid and message.getData() <> invalid
      print "IMA DAI SDK Error ";message.getData()
    end if
  end sub
  ]]>
  </script>
  <children>
    <Video height="720" id="myVideo" visible="false" width="1280"/>
  </children>
</component>

建立 IMA 串流播放器

接下來，您必須使用現有的 roVideoScreen 建立 IMA 串流播放器。

直播活動廣告連播放送

針對直播，這個串流播放器會實作三種回呼方法：streamInitialized、adBreakStarted 和 adBreakEnded。

並在串流載入時停用快速播放功能。這樣可以避免使用者在片頭廣告開始播放時，在系統觸發廣告插播事件前就略過片頭廣告。

Sdk.xml

<?xml version="1.0" encoding="utf-8" ?>

  <component name="IMASDKTask" extends="Task">
  <interface>
    <field id="IMASDKInitialized" type="Boolean" />
    <field id="errors" type="stringarray" />
    <field id="urlData" type="assocarray" />
    <field id="adPlaying" type="Boolean" />
    <field id="videoNode" type="Node" />
  </interface>

  <script type="text/brightscript">
  ...
  sub runThread()
    if not m.top.IMASDKInitialized
      initializeIMASDK()
    end if

    setupPlayerCallbacks()
  end sub
  ...
  sub initializeIMASDK()
    if m.ima = invalid
      ima = New_IMASDK()
      ima.initSdk()
      m.ima = ima
    end if
    m.top.IMASDKInitialized = true
  end sub

  sub setupPlayerCallbacks()
    m.player = m.ima.createPlayer()
    m.player.top = m.top

    m.player.streamInitialized = function(urlData)
      m.top.videoNode.enableTrickPlay = false
      m.top.urlData = urlData
    end function

    m.player.adBreakStarted = function(adBreakInfo)
      print "------ Ad break started ------"
      m.top.adPlaying = true
      m.top.videoNode.enableTrickPlay = false
    end function

    m.player.adBreakEnded = function(adBreakInfo)
      print "------ Ad break ended ------"
      m.top.adPlaying = false
      m.top.videoNode.enableTrickPlay = true
    end function

  end sub
  </script>
...
</component>

VOD 串流廣告連播放送

針對 VOD 串流，這個串流播放器會實作四種回呼方法：streamInitialized、loadUrl、adBreakStarted 和 adBreakEnded。請務必在 streamInitialized 回呼中呼叫 StreamManager.loadThirdPartyStream()。否則 SDK 不會觸發 loadUrl 函式。

在這個步驟中，您還會使用在 loadAdPodStream() 中取得的串流 ID，向影片技術合作夥伴 (VTP) 要求串流網址。接著，請使用廣告連播資訊清單和 VTP 傳回的任何字幕，呼叫 StreamManager.loadThirdPartyStream()。

並在串流載入時停用快速播放功能。這樣可避免使用者在片頭廣告開始播放後，在廣告插播開始事件觸發前略過廣告。

Sdk.xml

<?xml version="1.0" encoding="utf-8" ?>

  <component name="IMASDKTask" extends="Task">
  <interface>
    <field id="IMASDKInitialized" type="Boolean" />
    <field id="errors" type="stringarray" />
    <field id="adStitchedStreamInfo" type="assocarray" />
    <field id="adPlaying" type="Boolean" />
    <field id="videoNode" type="Node" />
    <field id="streamParameters" type="assocarray" />
  </interface>

  <script type="text/brightscript">
  ...
  sub runThread()
    if not m.top.IMASDKInitialized
      initializeIMASDK()
    end if

    setupPlayerCallbacks()
  end sub
  ...
  sub initializeIMASDK()
    if m.ima = invalid
      ima = New_IMASDK()
      ima.initSdk()
      m.ima = ima
    end if
    m.top.IMASDKInitialized = true
  end sub

  sub loadThirdPartyStream(adStitchedManifest as string, subtitleConfig as dynamic)
    m.streamManager.loadThirdPartyStream(adStitchedManifest, subtitleConfig)
  end sub

  sub setupPlayerCallbacks()
    m.player = m.ima.createPlayer()
    m.player.top = m.top

    m.player.streamInitialized = function(urlData)
      adStitchedManifest = m.top.streamParameters.VTPManifest.replace("[[STREAMID]]", urlData.streamId)
      loadThirdPartyStream(adStitchedManifest, m.top.streamParameters.subtitleConfig)
    end function

    m.player.loadUrl = function(streamInfo)
      m.top.adStitchedStreamInfo = streamInfo
    end function

    m.player.adBreakStarted = function(adBreakInfo)
      print "------ Ad break started ------"
      m.top.adPlaying = true
      m.top.videoNode.enableTrickPlay = false
    end function

    m.player.adBreakEnded = function(adBreakInfo)
      print "------ Ad break ended ------"
      m.top.adPlaying = false
      m.top.videoNode.enableTrickPlay = true
    end function

  end sub
  </script>
...
</component>

建立及執行直播或 VOD 廣告連播放送串流要求

建立串流播放器後，您可以建立並執行串流要求。這個範例包含 Pod 服務串流的資料，這些資料儲存在 m.testPodServingStream 中。

直播廣告連播放送

在 m.testPodServingStream 物件中，儲存 Google Ad Manager 識別相關串流所需的參數，例如聯播網代碼和自訂素材資源金鑰。同時儲存用來存取資訊清單操縱伺服器的資訊清單網址。在這種情況下，系統會在系統傳回串流要求後，新增資訊清單網址中的 Google 串流 ID。

如要支援 AdUI (例如 adChoices 圖示)，您必須在要求中傳遞包含內容影片的節點參照。

MainScene.xml

function init()
  m.video = m.top.findNode("myVideo")
  m.video.notificationinterval = 1
  m.testPodServingStream = {
    title: "Test live stream for DAI Pod Serving",
    assetKey: "test-live-stream",
    networkCode: "your-network-code",
    manifest: "https://.../master.m3u8?stream_id=[[STREAMID]]",
    apiKey: ""
  }
  runIMASDKTask()
end function

function runIMASDKTask()
  m.IMASDKTask = createObject("roSGNode", "IMASDKTask")

  m.IMASDKTask.streamParameters = m.testPodservingStream
  m.IMASDKTask.videoNode = m.video

  m.IMASDKTask.observeField("IMASDKInitialized", "handleIMASDKInitialized")
  m.IMASDKTask.observeField("errors", "handleIMASDKErrors")

  m.IMASDKTask.control = "RUN"
end function

Sdk.xml

<interface>
  <field id="IMASDKInitialized" type="Boolean" />
  <field id="errors" type="stringarray" />
  <field id="urlData" type="assocarray" />
  <field id="adPlaying" type="Boolean" />
  <field id="videoNode" type="Node" />
  <field id="streamParameters" type="assocarray" />
</interface>

...

sub runThread()
  if not m.top.IMASDKInitialized
    initializeIMASDK()
  end if

  setupPlayerCallbacks()
  loadAdPodStream()
end sub

sub loadAdPodStream()
  request = m.ima.CreatePodLiveStreamRequest(m.top.streamParameters.assetKey, m.top.streamParameters.networkCode, m.top.streamParameters.apiKey)

  ' Set the player object so that the request can trigger the player's
  ' callbacks at stream initialization or playback events.
  request.player = m.player

  ' Set the video node for the IMA DAI SDK to create ad UI as its child nodes.
  request.adUiNode = m.top.video

  requestResult = m.ima.requestStream(request)
  if requestResult <> invalid
    print "Error requesting stream ";requestResult
    return
  end if

  m.streamManager = invalid
  while m.streamManager = invalid
    sleep(50)
    m.streamManager = m.ima.getStreamManager()
  end while

  if m.streamManager = invalid
    errors = CreateObject("roArray", 1, True)
    invalidStreamManagerError = "Invalid stream manager"
    print invalidStreamManagerError
    errors.push(invalidStreamManagerError)
    m.top.errors = errors
    return
  end if

  if m.streamManager["type"] <> invalid and m.streamManager["type"] = "error"
    errors = CreateObject("roArray", 1, True)
    print "Stream request returns an error. " ; m.streamManager["info"]
    errors.push(m.streamManager["info"])
    m.top.errors = errors
    return
  end if

  setupStreamManager()
  m.streamManager.start()
end sub

VOD 串流廣告連播放送

在 m.testPodServingStream 物件中，您會儲存串流要求中使用的網路代碼，以便 Google Ad Manager 提供串流 ID。另外，請儲存用於在資訊清單操作伺服器上存取使用者專屬資訊清單的資訊清單網址。

如要支援 AdUI (例如 AdChoices 圖示)，您必須在請求中傳遞包含內容影片的節點參照。

MainScene.xml

sub init()
  m.video = m.top.findNode("myVideo")
  m.video.notificationinterval = 1
  m.testPodServingStream = {
    title: "Pod Serving VOD Stream",
    networkCode: "your-network-code",
    VTPManifest: "https://.../manifest.m3u8?gam-stream-id=[[STREAMID]]",
    subtitleConfig: []
  }
  runIMASDKTask()
end sub

sub runIMASDKTask()
  m.IMASDKTask = createObject("roSGNode", "IMASDKTask")

  m.IMASDKTask.streamParameters = m.testPodservingStream
  m.IMASDKTask.videoNode = m.video

  m.IMASDKTask.observeField("IMASDKInitialized", "handleIMASDKInitialized")
  m.IMASDKTask.observeField("errors", "handleIMASDKErrors")

  m.IMASDKTask.control = "RUN"
end sub

Sdk.xml

sub runThread()
  if not m.top.IMASDKInitialized
    initializeIMASDK()
  end if

  setupPlayerCallbacks()
  loadAdPodStream()
end sub

sub loadAdPodStream()
  request = m.ima.CreatePodVodStreamRequest(m.top.streamParameters.networkCode)

  ' Set the player object so that the request can trigger the player
  ' callbacks at stream initialization or playback events.
  request.player = m.player

  ' Set the video node for the IMA DAI SDK to create ad UI as its child nodes.
  request.adUiNode = m.top.video

  requestResult = m.ima.requestStream(request)
  if requestResult <> invalid
    print "Error requesting stream ";requestResult
    return
  end if

  m.streamManager = invalid
  while m.streamManager = invalid
    sleep(50)
    m.streamManager = m.ima.getStreamManager()
  end while

  if m.streamManager = invalid
    errors = CreateObject("roArray", 1, True)
    invalidStreamManagerError = "Invalid stream manager"
    print invalidStreamManagerError
    errors.push(invalidStreamManagerError)
    m.top.errors = errors
    return
  end if

  if m.streamManager["type"] <> invalid and m.streamManager["type"] = "error"
    errors = CreateObject("roArray", 1, True)
    print "Stream request returns an error. " ; m.streamManager["info"]
    errors.push(m.streamManager["info"])
    m.top.errors = errors
    return
  end if

  setupStreamManager()
  m.streamManager.start()
end sub

新增事件監聽器並啟動串流

直播廣告連播放送

要求串流後，只剩下幾項工作：新增事件監聽器來追蹤廣告進度，並將 Roku 訊息轉送至 SDK。請務必將所有訊息轉寄至 SDK，確保正確播放廣告。否則將造成系統錯誤檢舉廣告觀看次數。

在這個步驟中，您也要新增函式，將 [[STREAMID]] 巨集替換為串流 ID，並將完成的資訊清單要求網址傳遞至影片播放器。這個實作會在這個步驟中取得串流 ID，但視 VTP 整合方式而定，可能會在這個步驟之前取得。

MainScene.xml

function runIMASDKTask()
  m.IMASDKTask = createObject("roSGNode", "IMASDKTask")

  m.IMASDKTask.streamParameters = m.testPodservingStream
  m.IMASDKTask.videoNode = m.video

  m.IMASDKTask.observeField("IMASDKInitialized", "handleIMASDKInitialized")
  m.IMASDKTask.observeField("errors", "handleIMASDKErrors")
  m.sdkTask.observeField("adStitchedStreamInfo", "loadAdStitchedStream")

  m.sdkTask.control = "RUN"
end function

sub loadAdStitchedStream(message as object)
  print "Ad pod stream information ";message
  adPodStreamInfo = message.getData()
  manifest = m.testPodservingStream.manifest.Replace("[[STREAMID]]", adPodStreamInfo.streamId)
  playStream(manifest, adPodStreamInfo.format)
end sub

sub playStream(url as string, format as string)
  vidContent = createObject("RoSGNode", "ContentNode")
  vidContent.url = url
  vidContent.title = m.testPodservingStream.title
  vidContent.streamformat = format
  m.video.content = vidContent
  m.video.setFocus(true)
  m.video.visible = true
  m.video.control = "play"
  m.video.EnableCookies()
end sub

Sdk.xml

sub runThread()
  if not m.top.IMASDKInitialized
    initializeIMASDK()
  end if

  setupPlayerCallbacks()
  loadAdPodStream()
  if m.streamManager <> invalid
    runLoop()
  end if
end sub

sub runLoop()
  m.top.videoNode.timedMetaDataSelectionKeys = ["*"]

  ' IMPORTANT: Failure to listen to the position and timedmetadata fields
  ' could result in ad impressions not being reported.
  m.port = CreateObject("roMessagePort")
  m.top.videoNode.observeField("position", m.port)
  m.top.videoNode.observeField("timedMetaData", m.port)
  m.top.videoNode.observeField("timedMetaData2", m.port)
  m.top.videoNode.observeField("state", m.port)

  while True
    msg = wait(1000, m.port)
    if m.top.videoNode = invalid
      print "exiting"
      exit while
    end if

    m.streamManager.onMessage(msg)
    currentTime = m.top.videoNode.position
    if currentTime > 3 And not m.top.adPlaying
      m.top.videoNode.enableTrickPlay = true
    end if
  end while
end sub

sub setupStreamManager()
  m.streamManager.addEventListener(m.sdk.AdEvent.ERROR, errorCallback)
  m.streamManager.addEventListener(m.sdk.AdEvent.START, startCallback)
  m.streamManager.addEventListener(m.sdk.AdEvent.FIRST_QUARTILE, firstQuartileCallback)
  m.streamManager.addEventListener(m.sdk.AdEvent.MIDPOINT, midpointCallback)
  m.streamManager.addEventListener(m.sdk.AdEvent.THIRD_QUARTILE, thirdQuartileCallback)
  m.streamManager.addEventListener(m.sdk.AdEvent.COMPLETE, completeCallback)
end sub

sub startCallback(ad as object)
  print "Callback from SDK -- Start called - "
end sub

sub firstQuartileCallback(ad as object)
  print "Callback from SDK -- First quartile called - "
end sub

sub midpointCallback(ad as object)
  print "Callback from SDK -- Midpoint called - "
end sub

sub thirdQuartileCallback(ad as object)
  print "Callback from SDK -- Third quartile called - "
end sub

sub completeCallback(ad as object)
  print "Callback from SDK -- Complete called - "
end sub

function errorCallback(error as object)
  print "Callback from SDK -- Error called - " ; error
  m.errorState = True
end function

VOD 串流廣告連播放送

要求串流後，只剩下幾項工作：新增事件監聽器來追蹤廣告進度，並將 Roku 訊息轉送至 SDK。請務必將所有訊息轉寄至 SDK，確保正確播放廣告。否則系統將以錯誤的方式回報廣告觀看次數。

MainScene.xml

sub runIMASDKTask()
  m.IMASDKTask = createObject("roSGNode", "IMASDKTask")

  m.IMASDKTask.streamParameters = m.testPodservingStream
  m.IMASDKTask.videoNode = m.video

  m.IMASDKTask.observeField("IMASDKInitialized", "handleIMASDKInitialized")
  m.IMASDKTask.observeField("errors", "handleIMASDKErrors")
  m.sdkTask.observeField("adStitchedStreamInfo", "loadAdStitchedStream")

  m.sdkTask.control = "RUN"
end sub

sub loadAdStitchedStream(message as object)
  print "Ad pod stream information ";message
  adPodStreamInfo = message.getData()
end sub

sub playStream(url as string, format as string, subtitleConfig as object)
  vidContent = createObject("RoSGNode", "ContentNode")
  vidContent.title = m.testPodservingStream.title
  vidContent.url = url
  vidContent.subtitleConfig = subtitleConfig
  vidContent.streamformat = format
  m.video.content = vidContent
  m.video.setFocus(true)
  m.video.visible = true
  m.video.control = "play"
  m.video.EnableCookies()
end sub

Sdk.xml

sub runThread()
  if not m.top.IMASDKInitialized
    initializeIMASDK()
  end if

  setupPlayerCallbacks()
  loadAdPodStream()
  if m.streamManager <> invalid
    runLoop()
  end if
end sub

sub runLoop()
  m.top.videoNode.timedMetaDataSelectionKeys = ["*"]

  ' IMPORTANT: Failure to listen to the position and timedmetadata fields
  ' could result in ad impressions not being reported.
  m.port = CreateObject("roMessagePort")
  m.top.videoNode.observeField("position", m.port)
  m.top.videoNode.observeField("timedMetaData", m.port)
  m.top.videoNode.observeField("timedMetaData2", m.port)
  m.top.videoNode.observeField("state", m.port)

  while True
    msg = wait(1000, m.port)
    if m.top.videoNode = invalid
      exit while
    end if

    m.streamManager.onMessage(msg)
    currentTime = m.top.videoNode.position
    if currentTime > 3 and not m.top.adPlaying
      m.top.videoNode.enableTrickPlay = true
    end if
  end while
end sub

sub setupStreamManager()
  m.streamManager.addEventListener(m.sdk.AdEvent.ERROR, errorCallback)
  m.streamManager.addEventListener(m.sdk.AdEvent.START, startCallback)
  m.streamManager.addEventListener(m.sdk.AdEvent.FIRST_QUARTILE, firstQuartileCallback)
  m.streamManager.addEventListener(m.sdk.AdEvent.MIDPOINT, midpointCallback)
  m.streamManager.addEventListener(m.sdk.AdEvent.THIRD_QUARTILE, thirdQuartileCallback)
  m.streamManager.addEventListener(m.sdk.AdEvent.COMPLETE, completeCallback)
end sub

sub startCallback(ad as object)
  print "Callback from SDK -- Start called - "
end sub

sub firstQuartileCallback(ad as object)
  print "Callback from SDK -- First quartile called - "
end sub

sub midpointCallback(ad as object)
  print "Callback from SDK -- Midpoint called - "
end sub

sub thirdQuartileCallback(ad as object)
  print "Callback from SDK -- Third quartile called - "
end sub

sub completeCallback(ad as object)
  print "Callback from SDK -- Complete called - "
end sub

sub errorCallback(error as object)
  print "Callback from SDK -- Error called - " ; error
  m.errorState = True
end sub