IMA not playing all Ads from a midroll

[fpittersacc]

[REQUIRED] Issue description

The following IMA Ad Uri is producing an undesired behavior, in which not all Ads in the Midrolls are being played. After 2-3 Ads (out of 7 or 8) content is getting resumed.

It seems that the state hold by AdPlaybackState AdGroup.count differs from what AdPodInfo.getTotalAds() is providing after the actual Ad sequence is loaded.

[REQUIRED] Reproduction steps

1. On Exoplayer demo module, include the IMA Uri from below into a content longer than 10 min to allow midrolls to be reached.
2. Play midrolls.

Expected: All 7/8 Ads are played.
Actual: Only first 2/3 Ads are played and it continues with Content. (Depending on the Exo version)

[REQUIRED] Link to test content

https://pubads.g.doubleclick.net/gampad/ads?env=vp&gdfp_req=1&unviewed_position_start=1&output=vast&iu=/5374/TV2video/avod/programmer/underholdning/love-island-uk/sesong-5&sz=640x480&description_url=https://www.tv2.no/v/1463716&hl=no&cmsid=2510181&vid=1463716

[REQUIRED] A full bug report captured from the device

Notice the behavior/result is slightly different from 2.11.3 and 2.11.5

2.11.3 is logging some warning after the 3rd Ad is played and content playback continues
ImaAdsLoader: Unexpected ad count in LOADED, 7, expected 3

2.11.5 is logging the following exception after the 2nd Ad is played and content playback continues.

2020-06-08 13:08:00.792 8357-8357/com.google.android.exoplayer2.demo E/ImaAdsLoader: Internal error in loadAd
      java.lang.IllegalArgumentException
        at com.google.android.exoplayer2.util.Assertions.checkArgument(Assertions.java:39)
        at com.google.android.exoplayer2.source.ads.AdPlaybackState$AdGroup.withAdUri(AdPlaybackState.java:151)
        at com.google.android.exoplayer2.source.ads.AdPlaybackState.withAdUri(AdPlaybackState.java:399)
        at com.google.android.exoplayer2.ext.ima.ImaAdsLoader.loadAd(ImaAdsLoader.java:872)
        at com.google.ads.interactivemedia.v3.internal.akf.a(IMASDK:23)
        at com.google.ads.interactivemedia.v3.internal.akb.a(IMASDK:177)
        at com.google.ads.interactivemedia.v3.internal.akb.a(IMASDK:43)
        at com.google.ads.interactivemedia.v3.internal.ake.b(IMASDK:28)
        at com.google.ads.interactivemedia.v3.internal.akc.shouldOverrideUrlLoading(IMASDK:6)
        at android.webkit.WebViewClient.shouldOverrideUrlLoading(WebViewClient.java:77)
        at org.chromium.android_webview.AwContentsClientBridge.shouldOverrideUrlLoading(chromium-Monochrome.aab-stable-410409673:16)
        at android.os.MessageQueue.nativePollOnce(Native Method)
        at android.os.MessageQueue.next(MessageQueue.java:326)
        at android.os.Looper.loop(Looper.java:165)
        at android.app.ActivityThread.main(ActivityThread.java:6810)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
2020-06-08 13:08:00.796 8357-8357/com.google.android.exoplayer2.demo E/EventLogger: internalError [eventTime=29.60, mediaPos=0.21, window=0, loadError
      com.google.android.exoplayer2.source.ads.AdsMediaSource$AdLoadException: java.lang.RuntimeException: Internal error in loadAd
        at com.google.android.exoplayer2.ext.ima.ImaAdsLoader.maybeNotifyInternalError(ImaAdsLoader.java:1440)
        at com.google.android.exoplayer2.ext.ima.ImaAdsLoader.loadAd(ImaAdsLoader.java:875)
        at com.google.ads.interactivemedia.v3.internal.akf.a(IMASDK:23)
        at com.google.ads.interactivemedia.v3.internal.akb.a(IMASDK:177)
        at com.google.ads.interactivemedia.v3.internal.akb.a(IMASDK:43)
        at com.google.ads.interactivemedia.v3.internal.ake.b(IMASDK:28)
        at com.google.ads.interactivemedia.v3.internal.akc.shouldOverrideUrlLoading(IMASDK:6)
        at android.webkit.WebViewClient.shouldOverrideUrlLoading(WebViewClient.java:77)
        at org.chromium.android_webview.AwContentsClientBridge.shouldOverrideUrlLoading(chromium-Monochrome.aab-stable-410409673:16)
        at android.os.MessageQueue.nativePollOnce(Native Method)
        at android.os.MessageQueue.next(MessageQueue.java:326)
        at android.os.Looper.loop(Looper.java:165)
        at android.app.ActivityThread.main(ActivityThread.java:6810)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
     Caused by: java.lang.RuntimeException: Internal error in loadAd
        at com.google.android.exoplayer2.ext.ima.ImaAdsLoader.maybeNotifyInternalError(ImaAdsLoader.java:1439)
        at com.google.android.exoplayer2.ext.ima.ImaAdsLoader.loadAd(ImaAdsLoader.java:875) 
        at com.google.ads.interactivemedia.v3.internal.akf.a(IMASDK:23) 
        at com.google.ads.interactivemedia.v3.internal.akb.a(IMASDK:177) 
        at com.google.ads.interactivemedia.v3.internal.akb.a(IMASDK:43) 
        at com.google.ads.interactivemedia.v3.internal.ake.b(IMASDK:28) 
        at com.google.ads.interactivemedia.v3.internal.akc.shouldOverrideUrlLoading(IMASDK:6) 
        at android.webkit.WebViewClient.shouldOverrideUrlLoading(WebViewClient.java:77) 
        at org.chromium.android_webview.AwContentsClientBridge.shouldOverrideUrlLoading(chromium-Monochrome.aab-stable-410409673:16) 
        at android.os.MessageQueue.nativePollOnce(Native Method) 
        at android.os.MessageQueue.next(MessageQueue.java:326) 
        at android.os.Looper.loop(Looper.java:165) 
        at android.app.ActivityThread.main(ActivityThread.java:6810) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873) 
     Caused by: java.lang.IllegalArgumentException
        at com.google.android.exoplayer2.util.Assertions.checkArgument(Assertions.java:39)
        at com.google.android.exoplayer2.source.ads.AdPlaybackState$AdGroup.withAdUri(AdPlaybackState.java:151)
        at com.google.android.exoplayer2.source.ads.AdPlaybackState.withAdUri(AdPlaybackState.java:399)
        at com.google.android.exoplayer2.ext.ima.ImaAdsLoader.loadAd(ImaAdsLoader.java:872)
        at com.google.ads.interactivemedia.v3.internal.akf.a(IMASDK:23) 
        at com.google.ads.interactivemedia.v3.internal.akb.a(IMASDK:177) 
        at com.google.ads.interactivemedia.v3.internal.akb.a(IMASDK:43) 
        at com.google.ads.interactivemedia.v3.internal.ake.b(IMASDK:28) 
        at com.google.ads.interactivemedia.v3.internal.akc.shouldOverrideUrlLoading(IMASDK:6) 
        at android.webkit.WebViewClient.shouldOverrideUrlLoading(WebViewClient.java:77) 
        at org.chromium.android_webview.AwContentsClientBridge.shouldOverrideUrlLoading(chromium-Monochrome.aab-stable-410409673:16) 
        at android.os.MessageQueue.nativePollOnce(Native Method) 
        at android.os.MessageQueue.next(MessageQueue.java:326) 
        at android.os.Looper.loop(Looper.java:165) 
        at android.app.ActivityThread.main(ActivityThread.java:6810) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873) 
    ]

[REQUIRED] Version of ExoPlayer being used

2.11.3 & 2.11.5 (latest)

[REQUIRED] Device(s) and version(s) of Android being used

It doesn't seem to be affected by device / android version. All.

Potential solution

We have seen that if we allow to change AdGroup.count when the received one from the updated AdPod is greater than the one in the AdGroup, it seems to work.

In r2.11.5, on ImaAdsLoader.loadAd method we have included the mentioned condition.

      int adCount = Math.max(adPodInfo.getTotalAds(), adGroup.states.length);
      if (adGroup.count == C.LENGTH_UNSET || adCount > adGroup.count)) {
        adPlaybackState = adPlaybackState.withAdCount(adInfo.adGroupIndex, adCount);
        adGroup = adPlaybackState.adGroups[adInfo.adGroupIndex];
      }

Above requires that AdGroupd.withAdCount copy method doesn't check for count == C.LENGTH_UNSET condition.

It seems to be working fine for us so far, but I'm not sure if this is the proper solution. There are other places on ImaAdsLoader where AdPlaybackState.withAdCount is used.

** Sorry this didn't come before 2.11.5 was released :)

[andrewlewis]

Thanks for the report. Filed [Internal: b/159042225] to ask the IMA SDK team to take a look and advise whether this is working as intended, and if so what the cause is.

[andrewlewis]

Regarding the potential solution, I'd expect it to work as long as the final/correct ad count is known before the player buffers to the end of the last ad in the ad pod, but without understanding what's going on in more detail I'm not sure that is guaranteed.

[andrewlewis]

At the point of loading the first ad future ads in the pod may still be loading, and in general to total ad count is an estimate until the last ad in the pod loads.

I think it's safe just to remove the requirement that the ad count doesn't change as it looks like we discard buffered media periods as required to support this in MediaPeriodQueue. I will make a fix to do that.

[ojw28]

Fixed in the commits referenced above. This will be part of 2.11.6, which should be released today or tomorrow.

[fpittersacc]

Thanks, I can confirm this is working as intended.