TTML: Parse and use frameRate/Multiplier + tickRate

------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=126792535

TTML: Parse and use frameRate/Multiplier + tickRate
------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=126792535
85741ff2 · olly · Oliver Woodman · 2426907f · 85741ff2 · 85741ff2
Commit 85741ff2 authored Jul 07, 2016 by olly Committed by Oliver Woodman Jul 07, 2016
Showing with 98 additions and 22 deletions
library/src/androidTest/assets/ttml/frame_rate.xml
library/src/androidTest/java/com/google/android/exoplayer/text/ttml/TtmlParserTest.java
library/src/main/java/com/google/android/exoplayer/text/ttml/TtmlParser.java
--- a/library/src/androidTest/assets/ttml/frame_rate.xml
+++ b/library/src/androidTest/assets/ttml/frame_rate.xml
+<tt xmlns="http://www.w3.org/ns/ttml"
+    xmlns:ttp="http://www.w3.org/ns/ttml#parameter"
+    ttp:frameRate="50"
+    ttp:frameRateMultiplier="1000 1001"
+    ttp:tickRate="100">
+    <head>
+        <styling>
+        </styling>
+    </head>
+    <body>
+        <div>
+            <p begin="100t" end="101t">text 1</p>
+        </div>
+        <div>
+            <p begin="50000f" end="100000f">text 2</p>
+        </div>
+    </body>
+</tt>
--- a/library/src/androidTest/java/com/google/android/exoplayer/text/ttml/TtmlParserTest.java
+++ b/library/src/androidTest/java/com/google/android/exoplayer/text/ttml/TtmlParserTest.java
@@ -58,6 +58,7 @@ public final class TtmlParserTest extends InstrumentationTestCase {
  private static final String FONT_SIZE_MISSING_UNIT_TTML_FILE = "ttml/font_size_no_unit.xml";
  private static final String FONT_SIZE_INVALID_TTML_FILE = "ttml/font_size_invalid.xml";
  private static final String FONT_SIZE_EMPTY_TTML_FILE = "ttml/font_size_empty.xml";
+  private static final String FRAME_RATE_TTML_FILE = "ttml/frame_rate.xml";
  public void testInlineAttributes() throws IOException {
    TtmlSubtitle subtitle = getSubtitle(INLINE_ATTRIBUTES_TTML_FILE);
@@ -364,6 +365,15 @@ public final class TtmlParserTest extends InstrumentationTestCase {
    assertEquals(0, spannable.getSpans(0, spannable.length(), AbsoluteSizeSpan.class).length);
  }
+  public void testFrameRate() throws IOException {
+    TtmlSubtitle subtitle = getSubtitle(FRAME_RATE_TTML_FILE);
+    assertEquals(4, subtitle.getEventTimeCount());
+    assertEquals(1_000_000, subtitle.getEventTime(0));
+    assertEquals(1_010_000, subtitle.getEventTime(1));
+    assertEquals(1_001_000_000, subtitle.getEventTime(2), 1000);
+    assertEquals(2_002_000_000, subtitle.getEventTime(3), 2000);
+  }
  private void assertSpans(TtmlSubtitle subtitle, int second,
      String text, String font, int fontStyle,
      int backgroundColor, int color, boolean isUnderline,

--- a/library/src/main/java/com/google/android/exoplayer/text/ttml/TtmlParser.java
+++ b/library/src/main/java/com/google/android/exoplayer/text/ttml/TtmlParser.java
@@ -64,6 +64,8 @@ public final class TtmlParser extends SimpleSubtitleParser {
  private static final String TAG = "TtmlParser";
+  private static final String TTP = "http://www.w3.org/ns/ttml#parameter";
  private static final String ATTR_BEGIN = "begin";
  private static final String ATTR_DURATION = "dur";
  private static final String ATTR_END = "end";
@@ -79,10 +81,10 @@ public final class TtmlParser extends SimpleSubtitleParser {
  private static final Pattern PERCENTAGE_COORDINATES =
      Pattern.compile("^(\\d+\\.?\\d*?)% (\\d+\\.?\\d*?)%$");
-  // TODO: read and apply the following attributes if specified.
+  private static final int DEFAULT_FRAME_RATE = 30;
-  private static final int DEFAULT_FRAMERATE = 30;
-  private static final int DEFAULT_SUBFRAMERATE = 1;
+  private static final FrameAndTickRate DEFAULT_FRAME_AND_TICK_RATE =
-  private static final int DEFAULT_TICKRATE = 1;
+      new FrameAndTickRate(DEFAULT_FRAME_RATE, 1, 1);
  private final XmlPullParserFactory xmlParserFactory;
@@ -109,11 +111,15 @@ public final class TtmlParser extends SimpleSubtitleParser {
      LinkedList<TtmlNode> nodeStack = new LinkedList<>();
      int unsupportedNodeDepth = 0;
      int eventType = xmlParser.getEventType();
+      FrameAndTickRate frameAndTickRate = DEFAULT_FRAME_AND_TICK_RATE;
      while (eventType != XmlPullParser.END_DOCUMENT) {
        TtmlNode parent = nodeStack.peekLast();
        if (unsupportedNodeDepth == 0) {
          String name = xmlParser.getName();
          if (eventType == XmlPullParser.START_TAG) {
+            if (TtmlNode.TAG_TT.equals(name)) {
+              frameAndTickRate = parseFrameAndTickRates(xmlParser);
+            }
            if (!isSupportedTag(name)) {
              Log.i(TAG, "Ignoring unsupported tag: " + xmlParser.getName());
              unsupportedNodeDepth++;
@@ -121,7 +127,7 @@ public final class TtmlParser extends SimpleSubtitleParser {
              parseHeader(xmlParser, globalStyles, regionMap);
            } else {
              try {
-                TtmlNode node = parseNode(xmlParser, parent, regionMap);
+                TtmlNode node = parseNode(xmlParser, parent, regionMap, frameAndTickRate);
                nodeStack.addLast(node);
                if (parent != null) {
                  parent.addChild(node);
@@ -158,6 +164,39 @@ public final class TtmlParser extends SimpleSubtitleParser {
    }
  }
+  private FrameAndTickRate parseFrameAndTickRates(XmlPullParser xmlParser) throws ParserException {
+    int frameRate = DEFAULT_FRAME_RATE;
+    String frameRateStr = xmlParser.getAttributeValue(TTP, "frameRate");
+    if (frameRateStr != null) {
+      frameRate = Integer.parseInt(frameRateStr);
+    }
+    float frameRateMultiplier = 1;
+    String frameRateMultiplierStr = xmlParser.getAttributeValue(TTP, "frameRateMultiplier");
+    if (frameRateMultiplierStr != null) {
+      String[] parts = frameRateMultiplierStr.split(" ");
+      if (parts.length != 2) {
+        throw new ParserException("frameRateMultiplier doesn't have 2 parts");
+      }
+      float numerator = Integer.parseInt(parts[0]);
+      float denominator = Integer.parseInt(parts[1]);
+      frameRateMultiplier = numerator / denominator;
+    }
+    int subFrameRate = DEFAULT_FRAME_AND_TICK_RATE.subFrameRate;
+    String subFrameRateStr = xmlParser.getAttributeValue(TTP, "subFrameRate");
+    if (subFrameRateStr != null) {
+      subFrameRate = Integer.parseInt(subFrameRateStr);
+    }
+    int tickRate = DEFAULT_FRAME_AND_TICK_RATE.tickRate;
+    String tickRateStr = xmlParser.getAttributeValue(TTP, "tickRate");
+    if (tickRateStr != null) {
+      tickRate = Integer.parseInt(tickRateStr);
+    }
+    return new FrameAndTickRate(frameRate * frameRateMultiplier, subFrameRate, tickRate);
+  }
  private Map<String, TtmlStyle> parseHeader(XmlPullParser xmlParser,
      Map<String, TtmlStyle> globalStyles, Map<String, TtmlRegion> globalRegions)
      throws IOException, XmlPullParserException {
@@ -319,7 +358,7 @@ public final class TtmlParser extends SimpleSubtitleParser {
  }
  private TtmlNode parseNode(XmlPullParser parser, TtmlNode parent,
-      Map<String, TtmlRegion> regionMap) throws ParserException {
+      Map<String, TtmlRegion> regionMap, FrameAndTickRate frameAndTickRate) throws ParserException {
    long duration = 0;
    long startTime = TtmlNode.UNDEFINED_TIME;
    long endTime = TtmlNode.UNDEFINED_TIME;
@@ -332,16 +371,13 @@ public final class TtmlParser extends SimpleSubtitleParser {
      String value = parser.getAttributeValue(i);
      switch (attr) {
        case ATTR_BEGIN:
-          startTime = parseTimeExpression(value,
+          startTime = parseTimeExpression(value, frameAndTickRate);
-              DEFAULT_FRAMERATE, DEFAULT_SUBFRAMERATE, DEFAULT_TICKRATE);
          break;
        case ATTR_END:
-          endTime = parseTimeExpression(value,
+          endTime = parseTimeExpression(value, frameAndTickRate);
-              DEFAULT_FRAMERATE, DEFAULT_SUBFRAMERATE, DEFAULT_TICKRATE);
          break;
        case ATTR_DURATION:
-          duration = parseTimeExpression(value,
+          duration = parseTimeExpression(value, frameAndTickRate);
-              DEFAULT_FRAMERATE, DEFAULT_SUBFRAMERATE, DEFAULT_TICKRATE);
          break;
        case ATTR_STYLE:
          // IDREFS: potentially multiple space delimited ids
@@ -442,14 +478,12 @@ public final class TtmlParser extends SimpleSubtitleParser {
   * <a href="http://www.w3.org/TR/ttaf1-dfxp/#timing-value-timeExpression">timeExpression</a>
   *
   * @param time A string that includes the time expression.
-   * @param frameRate The frame rate of the stream.
+   * @param frameAndTickRate The effective frame and tick rates of the stream.
-   * @param subframeRate The sub-frame rate of the stream
-   * @param tickRate The tick rate of the stream.
   * @return The parsed timestamp in microseconds.
   * @throws ParserException If the given string does not contain a valid time expression.
   */
-  private static long parseTimeExpression(String time, int frameRate, int subframeRate,
+  private static long parseTimeExpression(String time, FrameAndTickRate frameAndTickRate)
-      int tickRate) throws ParserException {
+      throws ParserException {
    Matcher matcher = CLOCK_TIME.matcher(time);
    if (matcher.matches()) {
      String hours = matcher.group(1);
@@ -461,10 +495,13 @@ public final class TtmlParser extends SimpleSubtitleParser {
      String fraction = matcher.group(4);
      durationSeconds += (fraction != null) ? Double.parseDouble(fraction) : 0;
      String frames = matcher.group(5);
-      durationSeconds += (frames != null) ? ((double) Long.parseLong(frames)) / frameRate : 0;
+      durationSeconds += (frames != null)
+          ? Long.parseLong(frames) / frameAndTickRate.effectiveFrameRate : 0;
      String subframes = matcher.group(6);
-      durationSeconds += (subframes != null) ?
+      durationSeconds += (subframes != null)
-          ((double) Long.parseLong(subframes)) / subframeRate / frameRate : 0;
+          ? ((double) Long.parseLong(subframes)) / frameAndTickRate.subFrameRate
+              / frameAndTickRate.effectiveFrameRate
+          : 0;
      return (long) (durationSeconds * C.MICROS_PER_SECOND);
    }
    matcher = OFFSET_TIME.matcher(time);
@@ -486,10 +523,10 @@ public final class TtmlParser extends SimpleSubtitleParser {
          offsetSeconds /= 1000;
          break;
        case "f":
-          offsetSeconds /= frameRate;
+          offsetSeconds /= frameAndTickRate.effectiveFrameRate;
          break;
        case "t":
-          offsetSeconds /= tickRate;
+          offsetSeconds /= frameAndTickRate.tickRate;
          break;
      }
      return (long) (offsetSeconds * C.MICROS_PER_SECOND);
@@ -497,4 +534,15 @@ public final class TtmlParser extends SimpleSubtitleParser {
    throw new ParserException("Malformed time expression: " + time);
  }
+  private static final class FrameAndTickRate {
+    final float effectiveFrameRate;
+    final int subFrameRate;
+    final int tickRate;
+    FrameAndTickRate(float effectiveFrameRate, int subFrameRate, int tickRate) {
+      this.effectiveFrameRate = effectiveFrameRate;
+      this.subFrameRate = subFrameRate;
+      this.tickRate = tickRate;
+    }
+  }
 }