Export variant codecs in HLS

Issue:#1772

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=134073672

library/src/main/java/com/google/android/exoplayer2/Format.java

@@ -380,7 +380,7 @@ public final class Format implements Parcelable {
         selectionFlags, language, subsampleOffsetUs, initializationData, drmInitData);
         selectionFlags, language, subsampleOffsetUs, initializationData, drmInitData);
   }
   }
 
 
-  public Format copyWithContainerInfo(String id, int bitrate, int width, int height,
+  public Format copyWithContainerInfo(String id, String codecs, int bitrate, int width, int height,
       @C.SelectionFlags int selectionFlags, String language) {
       @C.SelectionFlags int selectionFlags, String language) {
     return new Format(id, containerMimeType, sampleMimeType, codecs, bitrate, maxInputSize,
     return new Format(id, containerMimeType, sampleMimeType, codecs, bitrate, maxInputSize,
         width, height, frameRate, rotationDegrees, pixelWidthHeightRatio, projectionData,
         width, height, frameRate, rotationDegrees, pixelWidthHeightRatio, projectionData,

library/src/main/java/com/google/android/exoplayer2/source/hls/HlsSampleStreamWrapper.java

@@ -15,6 +15,7 @@
  */
  */
 package com.google.android.exoplayer2.source.hls;
 package com.google.android.exoplayer2.source.hls;
 
 
+import android.text.TextUtils;
 import android.util.SparseArray;
 import android.util.SparseArray;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.Format;
@@ -567,7 +568,7 @@ import java.util.LinkedList;
       if (i == primaryExtractorTrackIndex) {
       if (i == primaryExtractorTrackIndex) {
         Format[] formats = new Format[chunkSourceTrackCount];
         Format[] formats = new Format[chunkSourceTrackCount];
         for (int j = 0; j < chunkSourceTrackCount; j++) {
         for (int j = 0; j < chunkSourceTrackCount; j++) {
-          formats[j] = getSampleFormat(chunkSourceTrackGroup.getFormat(j), sampleFormat);
+          formats[j] = deriveFormat(chunkSourceTrackGroup.getFormat(j), sampleFormat);
         }
         }
         trackGroups[i] = new TrackGroup(formats);
         trackGroups[i] = new TrackGroup(formats);
         primaryTrackGroupIndex = i;
         primaryTrackGroupIndex = i;
@@ -580,7 +581,7 @@ import java.util.LinkedList;
             trackFormat = muxedCaptionFormat;
             trackFormat = muxedCaptionFormat;
           }
           }
         }
         }
-        trackGroups[i] = new TrackGroup(getSampleFormat(trackFormat, sampleFormat));
+        trackGroups[i] = new TrackGroup(deriveFormat(trackFormat, sampleFormat));
       }
       }
     }
     }
     this.trackGroups = new TrackGroupArray(trackGroups);
     this.trackGroups = new TrackGroupArray(trackGroups);
@@ -599,18 +600,25 @@ import java.util.LinkedList;
   }
   }
 
 
   /**
   /**
-   * Derives a sample format corresponding to a given container format, by combining it with sample
-   * level information obtained from a second sample format.
+   * Derives a track format corresponding to a given container format, by combining it with sample
+   * level information obtained from the samples.
    *
    *
-   * @param containerFormat The container format for which the sample format should be derived.
+   * @param containerFormat The container format for which the track format should be derived.
    * @param sampleFormat A sample format from which to obtain sample level information.
    * @param sampleFormat A sample format from which to obtain sample level information.
-   * @return The derived sample format.
+   * @return The derived track format.
    */
    */
-  private static Format getSampleFormat(Format containerFormat, Format sampleFormat) {
+  private static Format deriveFormat(Format containerFormat, Format sampleFormat) {
     if (containerFormat == null) {
     if (containerFormat == null) {
       return sampleFormat;
       return sampleFormat;
     }
     }
-    return sampleFormat.copyWithContainerInfo(containerFormat.id, containerFormat.bitrate,
+    String codecs = null;
+    int sampleTrackType = MimeTypes.getTrackType(sampleFormat.sampleMimeType);
+    if (sampleTrackType == C.TRACK_TYPE_AUDIO) {
+      codecs = getAudioCodecs(containerFormat.codecs);
+    } else if (sampleTrackType == C.TRACK_TYPE_VIDEO) {
+      codecs = getVideoCodecs(containerFormat.codecs);
+    }
+    return sampleFormat.copyWithContainerInfo(containerFormat.id, codecs, containerFormat.bitrate,
         containerFormat.width, containerFormat.height, containerFormat.selectionFlags,
         containerFormat.width, containerFormat.height, containerFormat.selectionFlags,
         containerFormat.language);
         containerFormat.language);
   }
   }
@@ -623,4 +631,29 @@ import java.util.LinkedList;
     return pendingResetPositionUs != C.TIME_UNSET;
     return pendingResetPositionUs != C.TIME_UNSET;
   }
   }
 
 
+  private static String getAudioCodecs(String codecs) {
+    return getCodecsOfType(codecs, C.TRACK_TYPE_AUDIO);
+  }
+
+  private static String getVideoCodecs(String codecs) {
+    return getCodecsOfType(codecs, C.TRACK_TYPE_VIDEO);
+  }
+
+  private static String getCodecsOfType(String codecs, int trackType) {
+    if (TextUtils.isEmpty(codecs)) {
+      return null;
+    }
+    String[] codecArray = codecs.split("(\\s*,\\s*)|(\\s*$)");
+    StringBuilder builder = new StringBuilder();
+    for (String codec : codecArray) {
+      if (trackType == MimeTypes.getTrackTypeOfCodec(codec)) {
+        if (builder.length() > 0) {
+          builder.append(",");
+        }
+        builder.append(codec);
+      }
+    }
+    return builder.length() > 0 ? builder.toString() : null;
+  }
+
 }
 }

library/src/main/java/com/google/android/exoplayer2/util/MimeTypes.java

@@ -15,6 +15,9 @@
  */
  */
 package com.google.android.exoplayer2.util;
 package com.google.android.exoplayer2.util;
 
 
+import android.text.TextUtils;
+import com.google.android.exoplayer2.C;
+
 /**
 /**
  * Defines common MIME types and helper methods.
  * Defines common MIME types and helper methods.
  */
  */
@@ -192,6 +195,44 @@ public final class MimeTypes {
   }
   }
 
 
   /**
   /**
+   * Returns the {@link C}{@code .TRACK_TYPE_*} constant that corresponds to a specified mime type.
+   * {@link C#TRACK_TYPE_UNKNOWN} if the mime type is not known or the mapping cannot be
+   * established.
+   *
+   * @param mimeType The mimeType.
+   * @return The {@link C}{@code .TRACK_TYPE_*} constant that corresponds to a specified mime type.
+   */
+  public static int getTrackType(String mimeType) {
+    if (TextUtils.isEmpty(mimeType)) {
+      return C.TRACK_TYPE_UNKNOWN;
+    } else if (isAudio(mimeType)) {
+      return C.TRACK_TYPE_AUDIO;
+    } else if (isVideo(mimeType)) {
+      return C.TRACK_TYPE_VIDEO;
+    } else if (isText(mimeType) || APPLICATION_EIA608.equals(mimeType)
+        || APPLICATION_SUBRIP.equals(mimeType) || APPLICATION_TTML.equals(mimeType)
+        || APPLICATION_TX3G.equals(mimeType) || APPLICATION_MP4VTT.equals(mimeType)
+        || APPLICATION_RAWCC.equals(mimeType) || APPLICATION_VOBSUB.equals(mimeType)
+        || APPLICATION_PGS.equals(mimeType)) {
+      return C.TRACK_TYPE_TEXT;
+    } else if (APPLICATION_ID3.equals(mimeType)) {
+      return C.TRACK_TYPE_METADATA;
+    } else {
+      return C.TRACK_TYPE_UNKNOWN;
+    }
+  }
+
+  /**
+   * Equivalent to {@code getTrackType(getMediaMimeType(codec))}.
+   *
+   * @param codec The codec.
+   * @return The {@link C}{@code .TRACK_TYPE_*} constant that corresponds to a specified codec.
+   */
+  public static int getTrackTypeOfCodec(String codec) {
+    return getTrackType(getMediaMimeType(codec));
+  }
+
+  /**
    * Returns the top-level type of {@code mimeType}.
    * Returns the top-level type of {@code mimeType}.
    *
    *
    * @param mimeType The mimeType whose top-level type is required.
    * @param mimeType The mimeType whose top-level type is required.