Add support for H.263 and MPEG-4 Part 2 in TS

The new reader is named H263Reader as it handles H.263 streams, but
MPEG-4 Part 2 streams are also intended to be handled. The reader's
output format MIME type is video/mp4v as the H.263 streams can be
decoded by decoders supporting this MIME type.

The implementation is based on the framework implementation for
extracting MPEG-4 video in MPEG-TS
(https://cs.android.com/android/platform/superproject/+/master:frameworks/av/media/libstagefright/mpeg2ts/ESQueue.cpp;l=1825;drc=86e363c1fac27302ca4ae33e73296f7797672995)
and is similar to the existing H262Reader.

Issue: #1603
Issue: #5107
PiperOrigin-RevId: 320565337

RELEASENOTES.md

@@ -212,6 +212,9 @@
         headers mime type in `DefaultExtractorsFactory`.
     *   Add support for partially fragmented MP4s
         ([#7308](https://github.com/google/ExoPlayer/issues/7308)).
+    *   Add support for MPEG-4 Part 2 and H.263 in MPEG-TS
+        ([#1603](https://github.com/google/ExoPlayer/issues/1603),
+        [#5107](https://github.com/google/ExoPlayer/issues/5107)).
 *   Testing
     *   Add `TestExoPlayer`, a utility class with APIs to create
         `SimpleExoPlayer` instances with fake components for testing.

library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ts/DefaultTsPayloadReaderFactory.java

@@ -165,6 +165,8 @@ public TsPayloadReader createPayloadReader(int streamType, EsInfo esInfo) {
         return new PesReader(new DtsReader(esInfo.language));
       case TsExtractor.TS_STREAM_TYPE_H262:
         return new PesReader(new H262Reader(buildUserDataReader(esInfo)));
+      case TsExtractor.TS_STREAM_TYPE_H263:
+        return new PesReader(new H263Reader(buildUserDataReader(esInfo)));
       case TsExtractor.TS_STREAM_TYPE_H264:
         return isSet(FLAG_IGNORE_H264_STREAM) ? null
             : new PesReader(new H264Reader(buildSeiReader(esInfo),

library/extractor/src/main/java/com/google/android/exoplayer2/extractor/ts/H262Reader.java

@@ -15,14 +15,16 @@
  */
 package com.google.android.exoplayer2.extractor.ts;
 
+import static com.google.android.exoplayer2.util.Assertions.checkNotNull;
+import static com.google.android.exoplayer2.util.Assertions.checkStateNotNull;
+
 import android.util.Pair;
 import androidx.annotation.Nullable;
 import com.google.android.exoplayer2.C;
 import com.google.android.exoplayer2.Format;
 import com.google.android.exoplayer2.extractor.ExtractorOutput;
 import com.google.android.exoplayer2.extractor.TrackOutput;
 import com.google.android.exoplayer2.extractor.ts.TsPayloadReader.TrackIdGenerator;
-import com.google.android.exoplayer2.util.Assertions;
 import com.google.android.exoplayer2.util.MimeTypes;
 import com.google.android.exoplayer2.util.NalUnitUtil;
 import com.google.android.exoplayer2.util.ParsableByteArray;
@@ -118,7 +120,7 @@ public void packetStarted(long pesTimeUs, @TsPayloadReader.Flags int flags) {
 
   @Override
   public void consume(ParsableByteArray data) {
-    Assertions.checkStateNotNull(output); // Asserts that createTracks has been called.
+    checkStateNotNull(output); // Asserts that createTracks has been called.
     int offset = data.getPosition();
     int limit = data.limit();
     byte[] dataArray = data.data;
@@ -156,7 +158,7 @@ public void consume(ParsableByteArray data) {
         int bytesAlreadyPassed = lengthToStartCode < 0 ? -lengthToStartCode : 0;
         if (csdBuffer.onStartCode(startCodeValue, bytesAlreadyPassed)) {
           // The csd data is complete, so we can decode and output the media format.
-          Pair<Format, Long> result = parseCsdBuffer(csdBuffer, formatId);
+          Pair<Format, Long> result = parseCsdBuffer(csdBuffer, checkNotNull(formatId));
           output.format(result.first);
           frameDurationUs = result.second;
           hasOutputFormat = true;
@@ -215,11 +217,11 @@ public void packetFinished() {
    * Parses the {@link Format} and frame duration from a csd buffer.
    *
    * @param csdBuffer The csd buffer.
-   * @param formatId The id for the generated format. May be null.
+   * @param formatId The id for the generated format.
    * @return A pair consisting of the {@link Format} and the frame duration in microseconds, or 0 if
    *     the duration could not be determined.
    */
-  private static Pair<Format, Long> parseCsdBuffer(CsdBuffer csdBuffer, @Nullable String formatId) {
+  private static Pair<Format, Long> parseCsdBuffer(CsdBuffer csdBuffer, String formatId) {
     byte[] csdData = Arrays.copyOf(csdBuffer.data, csdBuffer.length);
 
     int firstByte = csdData[4] & 0xFF;