Fix TTML bitmap subtitles

+ Use start for anchoring, instead of center.
+ Add the height to the TTML bitmap cue rendering layout.

Issue:#5633
PiperOrigin-RevId: 250519710

RELEASENOTES.md

@@ -9,8 +9,11 @@
   checks ([#5568](https://github.com/google/ExoPlayer/issues/5568)).
 * Decoders: Prefer decoders that advertise format support over ones that do not,
   even if they are listed lower in the `MediaCodecList`.
-* CEA-608: Handle XDS and TEXT modes
-  ([5807](https://github.com/google/ExoPlayer/pull/5807)).
+* Subtitles:
+  * CEA-608: Handle XDS and TEXT modes
+  ([#5807](https://github.com/google/ExoPlayer/pull/5807)).
+  * TTML: Fix bitmap rendering
+  ([#5633](https://github.com/google/ExoPlayer/pull/5633)).
 * Audio:
  * Fix an issue where not all audio was played out when the configuration
    for the underlying track was changing (e.g., at some period transitions).

library/core/src/main/java/com/google/android/exoplayer2/text/ttml/TtmlDecoder.java

@@ -429,6 +429,7 @@ public final class TtmlDecoder extends SimpleSubtitleDecoder {
         /* lineType= */ Cue.LINE_TYPE_FRACTION,
         lineAnchor,
         width,
+        height,
         /* textSizeType= */ Cue.TEXT_SIZE_TYPE_FRACTIONAL_IGNORE_PADDING,
         /* textSize= */ regionTextHeight);
   }

library/core/src/main/java/com/google/android/exoplayer2/text/ttml/TtmlNode.java

@@ -231,11 +231,11 @@ import java.util.TreeSet;
           new Cue(
               bitmap,
               region.position,
-              Cue.ANCHOR_TYPE_MIDDLE,
+              Cue.ANCHOR_TYPE_START,
               region.line,
               region.lineAnchor,
               region.width,
-              /* height= */ Cue.DIMEN_UNSET));
+              region.height));
     }
 
     // Create text based cues.

library/core/src/main/java/com/google/android/exoplayer2/text/ttml/TtmlRegion.java

@@ -28,6 +28,7 @@ import com.google.android.exoplayer2.text.Cue;
   public final @Cue.LineType int lineType;
   public final @Cue.AnchorType int lineAnchor;
   public final float width;
+  public final float height;
   public final @Cue.TextSizeType int textSizeType;
   public final float textSize;
 
@@ -39,6 +40,7 @@ import com.google.android.exoplayer2.text.Cue;
         /* lineType= */ Cue.TYPE_UNSET,
         /* lineAnchor= */ Cue.TYPE_UNSET,
         /* width= */ Cue.DIMEN_UNSET,
+        /* height= */ Cue.DIMEN_UNSET,
         /* textSizeType= */ Cue.TYPE_UNSET,
         /* textSize= */ Cue.DIMEN_UNSET);
   }
@@ -50,6 +52,7 @@ import com.google.android.exoplayer2.text.Cue;
       @Cue.LineType int lineType,
       @Cue.AnchorType int lineAnchor,
       float width,
+      float height,
       int textSizeType,
       float textSize) {
     this.id = id;
@@ -58,6 +61,7 @@ import com.google.android.exoplayer2.text.Cue;
     this.lineType = lineType;
     this.lineAnchor = lineAnchor;
     this.width = width;
+    this.height = height;
     this.textSizeType = textSizeType;
     this.textSize = textSize;
   }

library/core/src/test/java/com/google/android/exoplayer2/text/ttml/TtmlDecoderTest.java

@@ -514,7 +514,7 @@ public final class TtmlDecoderTest {
     assertThat(cue.position).isEqualTo(24f / 100f);
     assertThat(cue.line).isEqualTo(28f / 100f);
     assertThat(cue.size).isEqualTo(51f / 100f);
-    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.bitmapHeight).isEqualTo(12f / 100f);
 
     cues = subtitle.getCues(4000000);
     assertThat(cues).hasSize(1);
@@ -524,7 +524,7 @@ public final class TtmlDecoderTest {
     assertThat(cue.position).isEqualTo(21f / 100f);
     assertThat(cue.line).isEqualTo(35f / 100f);
     assertThat(cue.size).isEqualTo(57f / 100f);
-    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.bitmapHeight).isEqualTo(6f / 100f);
 
     cues = subtitle.getCues(7500000);
     assertThat(cues).hasSize(1);
@@ -534,7 +534,7 @@ public final class TtmlDecoderTest {
     assertThat(cue.position).isEqualTo(24f / 100f);
     assertThat(cue.line).isEqualTo(28f / 100f);
     assertThat(cue.size).isEqualTo(51f / 100f);
-    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.bitmapHeight).isEqualTo(12f / 100f);
   }
 
   @Test
@@ -549,7 +549,7 @@ public final class TtmlDecoderTest {
     assertThat(cue.position).isEqualTo(307f / 1280f);
     assertThat(cue.line).isEqualTo(562f / 720f);
     assertThat(cue.size).isEqualTo(653f / 1280f);
-    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.bitmapHeight).isEqualTo(86f / 720f);
 
     cues = subtitle.getCues(4000000);
     assertThat(cues).hasSize(1);
@@ -559,7 +559,7 @@ public final class TtmlDecoderTest {
     assertThat(cue.position).isEqualTo(269f / 1280f);
     assertThat(cue.line).isEqualTo(612f / 720f);
     assertThat(cue.size).isEqualTo(730f / 1280f);
-    assertThat(cue.bitmapHeight).isEqualTo(Cue.DIMEN_UNSET);
+    assertThat(cue.bitmapHeight).isEqualTo(43f / 720f);
   }
 
   @Test