1 files changed, 259 insertions, 0 deletions
diff --git a/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/text/pgs/PgsDecoder.java b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/text/pgs/PgsDecoder.java
new file mode 100644
index 0000000000..859d240e9b
--- /dev/null
+++ b/mobile/android/exoplayer2/src/main/java/org/mozilla/thirdparty/com/google/android/exoplayer2/text/pgs/PgsDecoder.java
@@ -0,0 +1,259 @@
+/*
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.mozilla.thirdparty.com.google.android.exoplayer2.text.pgs;
+
+import android.graphics.Bitmap;
+import androidx.annotation.Nullable;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.text.Cue;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.text.SimpleSubtitleDecoder;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.text.Subtitle;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.text.SubtitleDecoderException;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.ParsableByteArray;
+import org.mozilla.thirdparty.com.google.android.exoplayer2.util.Util;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.zip.Inflater;
+
+/** A {@link SimpleSubtitleDecoder} for PGS subtitles. */
+public final class PgsDecoder extends SimpleSubtitleDecoder {
+
+  private static final int SECTION_TYPE_PALETTE = 0x14;
+  private static final int SECTION_TYPE_BITMAP_PICTURE = 0x15;
+  private static final int SECTION_TYPE_IDENTIFIER = 0x16;
+  private static final int SECTION_TYPE_END = 0x80;
+
+  private static final byte INFLATE_HEADER = 0x78;
+
+  private final ParsableByteArray buffer;
+  private final ParsableByteArray inflatedBuffer;
+  private final CueBuilder cueBuilder;
+
+  @Nullable private Inflater inflater;
+
+  public PgsDecoder() {
+    super("PgsDecoder");
+    buffer = new ParsableByteArray();
+    inflatedBuffer = new ParsableByteArray();
+    cueBuilder = new CueBuilder();
+  }
+
+  @Override
+  protected Subtitle decode(byte[] data, int size, boolean reset) throws SubtitleDecoderException {
+    buffer.reset(data, size);
+    maybeInflateData(buffer);
+    cueBuilder.reset();
+    ArrayList<Cue> cues = new ArrayList<>();
+    while (buffer.bytesLeft() >= 3) {
+      Cue cue = readNextSection(buffer, cueBuilder);
+      if (cue != null) {
+        cues.add(cue);
+      }
+    }
+    return new PgsSubtitle(Collections.unmodifiableList(cues));
+  }
+
+  private void maybeInflateData(ParsableByteArray buffer) {
+    if (buffer.bytesLeft() > 0 && buffer.peekUnsignedByte() == INFLATE_HEADER) {
+      if (inflater == null) {
+        inflater = new Inflater();
+      }
+      if (Util.inflate(buffer, inflatedBuffer, inflater)) {
+        buffer.reset(inflatedBuffer.data, inflatedBuffer.limit());
+      } // else assume data is not compressed.
+    }
+  }
+
+  @Nullable
+  private static Cue readNextSection(ParsableByteArray buffer, CueBuilder cueBuilder) {
+    int limit = buffer.limit();
+    int sectionType = buffer.readUnsignedByte();
+    int sectionLength = buffer.readUnsignedShort();
+
+    int nextSectionPosition = buffer.getPosition() + sectionLength;
+    if (nextSectionPosition > limit) {
+      buffer.setPosition(limit);
+      return null;
+    }
+
+    Cue cue = null;
+    switch (sectionType) {
+      case SECTION_TYPE_PALETTE:
+        cueBuilder.parsePaletteSection(buffer, sectionLength);
+        break;
+      case SECTION_TYPE_BITMAP_PICTURE:
+        cueBuilder.parseBitmapSection(buffer, sectionLength);
+        break;
+      case SECTION_TYPE_IDENTIFIER:
+        cueBuilder.parseIdentifierSection(buffer, sectionLength);
+        break;
+      case SECTION_TYPE_END:
+        cue = cueBuilder.build();
+        cueBuilder.reset();
+        break;
+      default:
+        break;
+    }
+
+    buffer.setPosition(nextSectionPosition);
+    return cue;
+  }
+
+  private static final class CueBuilder {
+
+    private final ParsableByteArray bitmapData;
+    private final int[] colors;
+
+    private boolean colorsSet;
+    private int planeWidth;
+    private int planeHeight;
+    private int bitmapX;
+    private int bitmapY;
+    private int bitmapWidth;
+    private int bitmapHeight;
+
+    public CueBuilder() {
+      bitmapData = new ParsableByteArray();
+      colors = new int[256];
+    }
+
+    private void parsePaletteSection(ParsableByteArray buffer, int sectionLength) {
+      if ((sectionLength % 5) != 2) {
+        // Section must be two bytes followed by a whole number of (index, y, cb, cr, a) entries.
+        return;
+      }
+      buffer.skipBytes(2);
+
+      Arrays.fill(colors, 0);
+      int entryCount = sectionLength / 5;
+      for (int i = 0; i < entryCount; i++) {
+        int index = buffer.readUnsignedByte();
+        int y = buffer.readUnsignedByte();
+        int cr = buffer.readUnsignedByte();
+        int cb = buffer.readUnsignedByte();
+        int a = buffer.readUnsignedByte();
+        int r = (int) (y + (1.40200 * (cr - 128)));
+        int g = (int) (y - (0.34414 * (cb - 128)) - (0.71414 * (cr - 128)));
+        int b = (int) (y + (1.77200 * (cb - 128)));
+        colors[index] =
+            (a << 24)
+                | (Util.constrainValue(r, 0, 255) << 16)
+                | (Util.constrainValue(g, 0, 255) << 8)
+                | Util.constrainValue(b, 0, 255);
+      }
+      colorsSet = true;
+    }
+
+    private void parseBitmapSection(ParsableByteArray buffer, int sectionLength) {
+      if (sectionLength < 4) {
+        return;
+      }
+      buffer.skipBytes(3); // Id (2 bytes), version (1 byte).
+      boolean isBaseSection = (0x80 & buffer.readUnsignedByte()) != 0;
+      sectionLength -= 4;
+
+      if (isBaseSection) {
+        if (sectionLength < 7) {
+          return;
+        }
+        int totalLength = buffer.readUnsignedInt24();
+        if (totalLength < 4) {
+          return;
+        }
+        bitmapWidth = buffer.readUnsignedShort();
+        bitmapHeight = buffer.readUnsignedShort();
+        bitmapData.reset(totalLength - 4);
+        sectionLength -= 7;
+      }
+
+      int position = bitmapData.getPosition();
+      int limit = bitmapData.limit();
+      if (position < limit && sectionLength > 0) {
+        int bytesToRead = Math.min(sectionLength, limit - position);
+        buffer.readBytes(bitmapData.data, position, bytesToRead);
+        bitmapData.setPosition(position + bytesToRead);
+      }
+    }
+
+    private void parseIdentifierSection(ParsableByteArray buffer, int sectionLength) {
+      if (sectionLength < 19) {
+        return;
+      }
+      planeWidth = buffer.readUnsignedShort();
+      planeHeight = buffer.readUnsignedShort();
+      buffer.skipBytes(11);
+      bitmapX = buffer.readUnsignedShort();
+      bitmapY = buffer.readUnsignedShort();
+    }
+
+    @Nullable
+    public Cue build() {
+      if (planeWidth == 0
+          || planeHeight == 0
+          || bitmapWidth == 0
+          || bitmapHeight == 0
+          || bitmapData.limit() == 0
+          || bitmapData.getPosition() != bitmapData.limit()
+          || !colorsSet) {
+        return null;
+      }
+      // Build the bitmapData.
+      bitmapData.setPosition(0);
+      int[] argbBitmapData = new int[bitmapWidth * bitmapHeight];
+      int argbBitmapDataIndex = 0;
+      while (argbBitmapDataIndex < argbBitmapData.length) {
+        int colorIndex = bitmapData.readUnsignedByte();
+        if (colorIndex != 0) {
+          argbBitmapData[argbBitmapDataIndex++] = colors[colorIndex];
+        } else {
+          int switchBits = bitmapData.readUnsignedByte();
+          if (switchBits != 0) {
+            int runLength =
+                (switchBits & 0x40) == 0
+                    ? (switchBits & 0x3F)
+                    : (((switchBits & 0x3F) << 8) | bitmapData.readUnsignedByte());
+            int color = (switchBits & 0x80) == 0 ? 0 : colors[bitmapData.readUnsignedByte()];
+            Arrays.fill(
+                argbBitmapData, argbBitmapDataIndex, argbBitmapDataIndex + runLength, color);
+            argbBitmapDataIndex += runLength;
+          }
+        }
+      }
+      Bitmap bitmap =
+          Bitmap.createBitmap(argbBitmapData, bitmapWidth, bitmapHeight, Bitmap.Config.ARGB_8888);
+      // Build the cue.
+      return new Cue(
+          bitmap,
+          (float) bitmapX / planeWidth,
+          Cue.ANCHOR_TYPE_START,
+          (float) bitmapY / planeHeight,
+          Cue.ANCHOR_TYPE_START,
+          (float) bitmapWidth / planeWidth,
+          (float) bitmapHeight / planeHeight);
+    }
+
+    public void reset() {
+      planeWidth = 0;
+      planeHeight = 0;
+      bitmapX = 0;
+      bitmapY = 0;
+      bitmapWidth = 0;
+      bitmapHeight = 0;
+      bitmapData.reset(0);
+      colorsSet = false;
+    }
+  }
+}