Reorder adaptive video track preferences.

This change moves the video track selection to the generic
selection method introcuced for audio and text. This ensures
we can apply the same criteria for fixed and adaptive video
track selections. Implicitly, this reorders the preferences
for adaptive tracks to give non-quality preferences (like
preferred MIME type or preferred role flags) a higher priority
than number of tracks in the selection.

Issue: google/ExoPlayer#9519
PiperOrigin-RevId: 422310902

RELEASENOTES.md

@@ -31,6 +31,9 @@
     *   Disable automatic speed adjustment for live streams that neither have
         low-latency features nor a user request setting the speed
         ((#9329)[https://github.com/google/ExoPlayer/issues/9329]).
+    *   Update video track selection logic to take preferred MIME types and role
+        flags into account when selecting multiple video tracks for adaptation
+        ((#9519)[https://github.com/google/ExoPlayer/issues/9519]).
 *   Android 12 compatibility:
     *   Upgrade the Cast extension to depend on
         `com.google.android.gms:play-services-cast-framework:20.1.0`. Earlier

library/core/src/test/java/com/google/android/exoplayer2/trackselection/DefaultTrackSelectorTest.java

@@ -1859,11 +1859,17 @@ public final class DefaultTrackSelectorTest {
       throws Exception {
     Format formatAv1 = new Format.Builder().setSampleMimeType(MimeTypes.VIDEO_AV1).build();
     Format formatVp9 = new Format.Builder().setSampleMimeType(MimeTypes.VIDEO_VP9).build();
-    Format formatH264 = new Format.Builder().setSampleMimeType(MimeTypes.VIDEO_H264).build();
-    TrackGroupArray trackGroups = wrapFormats(formatAv1, formatVp9, formatH264);
+    Format formatH264Low =
+        new Format.Builder().setSampleMimeType(MimeTypes.VIDEO_H264).setAverageBitrate(400).build();
+    Format formatH264High =
+        new Format.Builder().setSampleMimeType(MimeTypes.VIDEO_H264).setAverageBitrate(800).build();
+    // Use an adaptive group to check that MIME type has a higher priority than number of tracks.
+    TrackGroup adaptiveGroup = new TrackGroup(formatH264Low, formatH264High);
+    TrackGroupArray trackGroups =
+        new TrackGroupArray(new TrackGroup(formatAv1), new TrackGroup(formatVp9), adaptiveGroup);
 
     trackSelector.setParameters(
-        trackSelector.buildUponParameters().setPreferredVideoMimeType(MimeTypes.VIDEO_VP9));
+        defaultParameters.buildUpon().setPreferredVideoMimeType(MimeTypes.VIDEO_VP9));
     TrackSelectorResult result =
         trackSelector.selectTracks(
             new RendererCapabilities[] {VIDEO_CAPABILITIES}, trackGroups, periodId, TIMELINE);
@@ -1871,8 +1877,8 @@ public final class DefaultTrackSelectorTest {
     assertFixedSelection(result.selections[0], trackGroups, formatVp9);
 
     trackSelector.setParameters(
-        trackSelector
-            .buildUponParameters()
+        defaultParameters
+            .buildUpon()
             .setPreferredVideoMimeTypes(MimeTypes.VIDEO_VP9, MimeTypes.VIDEO_AV1));
     result =
         trackSelector.selectTracks(
@@ -1881,23 +1887,22 @@ public final class DefaultTrackSelectorTest {
     assertFixedSelection(result.selections[0], trackGroups, formatVp9);
 
     trackSelector.setParameters(
-        trackSelector
-            .buildUponParameters()
+        defaultParameters
+            .buildUpon()
             .setPreferredVideoMimeTypes(MimeTypes.VIDEO_DIVX, MimeTypes.VIDEO_H264));
     result =
         trackSelector.selectTracks(
             new RendererCapabilities[] {VIDEO_CAPABILITIES}, trackGroups, periodId, TIMELINE);
     assertThat(result.length).isEqualTo(1);
-    assertFixedSelection(result.selections[0], trackGroups, formatH264);
+    assertAdaptiveSelection(result.selections[0], adaptiveGroup, /* expectedTracks...= */ 1, 0);
 
-    // Select first in the list if no preference is specified.
-    trackSelector.setParameters(
-        trackSelector.buildUponParameters().setPreferredVideoMimeType(null));
+    // Select default (=most tracks) if no preference is specified.
+    trackSelector.setParameters(defaultParameters.buildUpon().setPreferredVideoMimeType(null));
     result =
         trackSelector.selectTracks(
             new RendererCapabilities[] {VIDEO_CAPABILITIES}, trackGroups, periodId, TIMELINE);
     assertThat(result.length).isEqualTo(1);
-    assertFixedSelection(result.selections[0], trackGroups, formatAv1);
+    assertAdaptiveSelection(result.selections[0], adaptiveGroup, /* expectedTracks...= */ 1, 0);
   }
 
   /**
@@ -1907,13 +1912,18 @@ public final class DefaultTrackSelectorTest {
   @Test
   public void selectTracks_withPreferredVideoRoleFlags_selectPreferredTrack() throws Exception {
     Format.Builder formatBuilder = VIDEO_FORMAT.buildUpon();
-    Format noRoleFlags = formatBuilder.build();
+    Format noRoleFlagsLow = formatBuilder.setAverageBitrate(4000).build();
+    Format noRoleFlagsHigh = formatBuilder.setAverageBitrate(8000).build();
     Format lessRoleFlags = formatBuilder.setRoleFlags(C.ROLE_FLAG_CAPTION).build();
     Format moreRoleFlags =
         formatBuilder
             .setRoleFlags(C.ROLE_FLAG_CAPTION | C.ROLE_FLAG_COMMENTARY | C.ROLE_FLAG_DUB)
             .build();
-    TrackGroupArray trackGroups = wrapFormats(noRoleFlags, moreRoleFlags, lessRoleFlags);
+    // Use an adaptive group to check that role flags have higher priority than number of tracks.
+    TrackGroup adaptiveNoRoleFlagsGroup = new TrackGroup(noRoleFlagsLow, noRoleFlagsHigh);
+    TrackGroupArray trackGroups =
+        new TrackGroupArray(
+            adaptiveNoRoleFlagsGroup, new TrackGroup(moreRoleFlags), new TrackGroup(lessRoleFlags));
 
     trackSelector.setParameters(
         defaultParameters