From a46716c0e999873f1354847e852c2abbc3c4d5b6 Mon Sep 17 00:00:00 2001
From: ibaker <ibaker@google.com>
Date: Tue, 12 Nov 2024 09:35:59 -0800
Subject: [PATCH] Handle `C.TIME_END_OF_SOURCE` buffer timestamps in
 `CeaDecoder`

The behaviour was changed in 1.4.0 with https://github.com/androidx/media/commit/0f42dd47526c70e38b1048bb18c994c281800485,
so that the buffer timestamp is compared to `outputStartTimeUs` when
deciding whether to discard a "decode only" buffer before decoding
(instead of the deprecated/removed `isDecodeOnly` property). This breaks
when the buffer timestamp is `TIME_END_OF_SOURCE` (which is
`Long.MIN_VALUE`), because `TIME_END_OF_SOURCE < outputStartTimeUs` is
always true, so the end-of-stream buffer is never passed to the decoder
and on to `TextRenderer` where it is used to
[set `inputStreamEnded = true`](https://github.com/androidx/media/blob/40f187e4b47c445af5049a5a49ee4633ce4c1a76/libraries/exoplayer/src/main/java/androidx/media3/exoplayer/text/TextRenderer.java#L434-L436)
and so playback hangs.

Issue: androidx/media#1863
PiperOrigin-RevId: 695767247
(cherry picked from commit 19b38c83b6ce1d13effc08da834cc8ff284cb969)
---
 RELEASENOTES.md                               |  2 ++
 .../media3/extractor/text/cea/CeaDecoder.java |  4 +++-
 .../extractor/text/cea/Cea608DecoderTest.java | 20 +++++++++++++++++++
 3 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/RELEASENOTES.md b/RELEASENOTES.md
index f83bff57efc..079d8d5fe80 100644
--- a/RELEASENOTES.md
+++ b/RELEASENOTES.md
@@ -5,6 +5,8 @@
 *   Text:
     *   Fix garbled CEA-608 subtitles in content with more than one SEI message
         per sample.
+    *   Fix playback hanging on DASH multi-period streams when CEA-608 subtitles
+        are enabled ([#1863](https://github.com/androidx/media/issues/1863)).
 
 ## 1.5
 
diff --git a/libraries/extractor/src/main/java/androidx/media3/extractor/text/cea/CeaDecoder.java b/libraries/extractor/src/main/java/androidx/media3/extractor/text/cea/CeaDecoder.java
index 00c44551448..79472f58055 100644
--- a/libraries/extractor/src/main/java/androidx/media3/extractor/text/cea/CeaDecoder.java
+++ b/libraries/extractor/src/main/java/androidx/media3/extractor/text/cea/CeaDecoder.java
@@ -84,7 +84,9 @@ public SubtitleInputBuffer dequeueInputBuffer() throws SubtitleDecoderException
   public void queueInputBuffer(SubtitleInputBuffer inputBuffer) throws SubtitleDecoderException {
     Assertions.checkArgument(inputBuffer == dequeuedInputBuffer);
     CeaInputBuffer ceaInputBuffer = (CeaInputBuffer) inputBuffer;
-    if (outputStartTimeUs != C.TIME_UNSET && ceaInputBuffer.timeUs < outputStartTimeUs) {
+    if (ceaInputBuffer.timeUs != C.TIME_END_OF_SOURCE
+        && outputStartTimeUs != C.TIME_UNSET
+        && ceaInputBuffer.timeUs < outputStartTimeUs) {
       // We can start decoding anywhere in CEA formats, so discarding on the input side is fine.
       releaseInputBuffer(ceaInputBuffer);
     } else {
diff --git a/libraries/extractor/src/test/java/androidx/media3/extractor/text/cea/Cea608DecoderTest.java b/libraries/extractor/src/test/java/androidx/media3/extractor/text/cea/Cea608DecoderTest.java
index 718499a0434..e7c222e744b 100644
--- a/libraries/extractor/src/test/java/androidx/media3/extractor/text/cea/Cea608DecoderTest.java
+++ b/libraries/extractor/src/test/java/androidx/media3/extractor/text/cea/Cea608DecoderTest.java
@@ -328,6 +328,26 @@ public void serviceSwitchOnField2Handled() throws Exception {
     assertThat(getOnlyCue(firstSubtitle).text.toString()).isEqualTo("test");
   }
 
+  // https://github.com/androidx/media/issues/1863
+  @Test
+  public void endOfStreamBuffer_flagPassedThrough() throws Exception {
+    Cea608Decoder decoder =
+        new Cea608Decoder(
+            MimeTypes.APPLICATION_CEA608,
+            /* accessibilityChannel= */ 1,
+            Cea608Decoder.MIN_DATA_CHANNEL_TIMEOUT_MS);
+
+    SubtitleInputBuffer inputBuffer = checkNotNull(decoder.dequeueInputBuffer());
+    inputBuffer.timeUs = C.TIME_END_OF_SOURCE;
+    inputBuffer.addFlag(C.BUFFER_FLAG_END_OF_STREAM);
+    decoder.setOutputStartTimeUs(0);
+    decoder.queueInputBuffer(inputBuffer);
+    decoder.setPositionUs(123);
+    SubtitleOutputBuffer outputBuffer = decoder.dequeueOutputBuffer();
+
+    assertThat(outputBuffer.isEndOfStream()).isTrue();
+  }
+
   private static byte[] createPacket(int header, int cc1, int cc2) {
     return new byte[] {
       UnsignedBytes.checkedCast(header),