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marcbaechingermarcbaechinger
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Merge pull request #53 from ittiam-systems:rtp_opus
PiperOrigin-RevId: 453490088
2 parents 527db57 + 165e706 commit ade3452

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‎library/rtsp/src/main/java/com/google/android/exoplayer2/source/rtsp/RtpPayloadFormat.java

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@@ -44,6 +44,7 @@ public final class RtpPayloadFormat {
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private static final String RTP_MEDIA_MPEG4_VIDEO = "MP4V-ES";
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private static final String RTP_MEDIA_H264 = "H264";
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private static final String RTP_MEDIA_H265 = "H265";
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private static final String RTP_MEDIA_OPUS = "OPUS";
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private static final String RTP_MEDIA_PCM_L8 = "L8";
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private static final String RTP_MEDIA_PCM_L16 = "L16";
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private static final String RTP_MEDIA_PCMA = "PCMA";
@@ -61,6 +62,7 @@ public static boolean isFormatSupported(MediaDescription mediaDescription) {
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case RTP_MEDIA_H265:
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case RTP_MEDIA_MPEG4_VIDEO:
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case RTP_MEDIA_MPEG4_GENERIC:
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case RTP_MEDIA_OPUS:
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case RTP_MEDIA_PCM_L8:
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case RTP_MEDIA_PCM_L16:
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case RTP_MEDIA_PCMA:
@@ -90,6 +92,8 @@ public static String getMimeTypeFromRtpMediaType(String mediaType) {
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return MimeTypes.AUDIO_AMR_WB;
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case RTP_MEDIA_MPEG4_GENERIC:
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return MimeTypes.AUDIO_AAC;
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case RTP_MEDIA_OPUS:
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return MimeTypes.AUDIO_OPUS;
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case RTP_MEDIA_PCM_L8:
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case RTP_MEDIA_PCM_L16:
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return MimeTypes.AUDIO_RAW;

‎library/rtsp/src/main/java/com/google/android/exoplayer2/source/rtsp/RtspMediaTrack.java

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@@ -99,6 +99,9 @@
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*/
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private static final int DEFAULT_VP8_HEIGHT = 240;
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/** RFC7587 Section 6.1 Sampling rate for OPUS is fixed at 48KHz. */
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private static final int OPUS_CLOCK_RATE = 48_000;
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/**
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* Default width for VP9.
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*
@@ -199,6 +202,12 @@ public int hashCode() {
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!fmtpParameters.containsKey(PARAMETER_AMR_INTERLEAVING),
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"Interleaving mode is not currently supported.");
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break;
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case MimeTypes.AUDIO_OPUS:
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checkArgument(channelCount != C.INDEX_UNSET);
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// RFC7587 Section 6.1: the RTP timestamp is incremented with a 48000 Hz clock rate
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// for all modes of Opus and all sampling rates.
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checkArgument(clockRate == OPUS_CLOCK_RATE, "Invalid OPUS clock rate.");
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break;
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case MimeTypes.VIDEO_MP4V:
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checkArgument(!fmtpParameters.isEmpty());
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processMPEG4FmtpAttribute(formatBuilder, fmtpParameters);

‎library/rtsp/src/main/java/com/google/android/exoplayer2/source/rtsp/reader/DefaultRtpPayloadReaderFactory.java

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@@ -37,6 +37,8 @@ public RtpPayloadReader createPayloadReader(RtpPayloadFormat payloadFormat) {
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case MimeTypes.AUDIO_AMR_NB:
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case MimeTypes.AUDIO_AMR_WB:
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return new RtpAmrReader(payloadFormat);
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case MimeTypes.AUDIO_OPUS:
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return new RtpOpusReader(payloadFormat);
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case MimeTypes.AUDIO_RAW:
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case MimeTypes.AUDIO_ALAW:
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case MimeTypes.AUDIO_MLAW:

‎library/rtsp/src/main/java/com/google/android/exoplayer2/source/rtsp/reader/RtpOpusReader.java

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@@ -0,0 +1,157 @@
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/*
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* Copyright 2022 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package com.google.android.exoplayer2.source.rtsp.reader;
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import static com.google.android.exoplayer2.util.Assertions.checkArgument;
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import static com.google.android.exoplayer2.util.Assertions.checkStateNotNull;
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import com.google.android.exoplayer2.C;
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import com.google.android.exoplayer2.Format;
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import com.google.android.exoplayer2.audio.OpusUtil;
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import com.google.android.exoplayer2.extractor.ExtractorOutput;
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import com.google.android.exoplayer2.extractor.TrackOutput;
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import com.google.android.exoplayer2.source.rtsp.RtpPacket;
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import com.google.android.exoplayer2.source.rtsp.RtpPayloadFormat;
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import com.google.android.exoplayer2.util.Log;
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import com.google.android.exoplayer2.util.ParsableByteArray;
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import com.google.android.exoplayer2.util.Util;
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import java.util.List;
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import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
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/**
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* Parses an OPUS byte stream carried on RTP packets and extracts individual samples. Refer to
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* RFC7845 for more details.
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*/
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/* package */ final class RtpOpusReader implements RtpPayloadReader {
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private static final String TAG = "RtpOpusReader";
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/* Opus uses a fixed 48KHz media clock RFC7845 Section 4. */
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private static final long MEDIA_CLOCK_FREQUENCY = 48_000;
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private final RtpPayloadFormat payloadFormat;
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private @MonotonicNonNull TrackOutput trackOutput;
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/**
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* First received RTP timestamp. All RTP timestamps are dimension-less, the time base is defined
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* by {@link #MEDIA_CLOCK_FREQUENCY}.
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*/
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private long firstReceivedTimestamp;
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private long startTimeOffsetUs;
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private int previousSequenceNumber;
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private boolean foundOpusIDHeader;
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private boolean foundOpusCommentHeader;
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/** Creates an instance. */
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public RtpOpusReader(RtpPayloadFormat payloadFormat) {
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this.payloadFormat = payloadFormat;
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this.firstReceivedTimestamp = C.INDEX_UNSET;
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this.previousSequenceNumber = C.INDEX_UNSET;
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}
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// RtpPayloadReader implementation.
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@Override
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public void createTracks(ExtractorOutput extractorOutput, int trackId) {
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trackOutput = extractorOutput.track(trackId, C.TRACK_TYPE_AUDIO);
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trackOutput.format(payloadFormat.format);
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}
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@Override
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public void onReceivingFirstPacket(long timestamp, int sequenceNumber) {
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this.firstReceivedTimestamp = timestamp;
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}
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@Override
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public void consume(
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ParsableByteArray data, long timestamp, int sequenceNumber, boolean rtpMarker) {
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checkStateNotNull(trackOutput);
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/* RFC7845 Section 3.
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* +---------+ +----------------+ +--------------------+ +-----
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* |ID Header| | Comment Header | |Audio Data Packet 1 | | ...
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* +---------+ +----------------+ +--------------------+ +-----
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*/
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if (!foundOpusIDHeader) {
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validateOpusIdHeader(data);
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List<byte[]> initializationData = OpusUtil.buildInitializationData(data.getData());
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Format.Builder formatBuilder = payloadFormat.format.buildUpon();
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formatBuilder.setInitializationData(initializationData);
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trackOutput.format(formatBuilder.build());
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foundOpusIDHeader = true;
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} else if (!foundOpusCommentHeader) {
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// Comment Header RFC7845 Section 5.2.
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int sampleSize = data.limit();
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checkArgument(sampleSize >= 8, "Comment Header has insufficient data");
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String header = data.readString(8);
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checkArgument(header.equals("OpusTags"), "Comment Header should follow ID Header");
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foundOpusCommentHeader = true;
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} else {
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// Check that this packet is in the sequence of the previous packet.
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int expectedSequenceNumber = RtpPacket.getNextSequenceNumber(previousSequenceNumber);
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if (sequenceNumber != expectedSequenceNumber) {
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Log.w(
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TAG,
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Util.formatInvariant(
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"Received RTP packet with unexpected sequence number. Expected: %d; received: %d.",
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expectedSequenceNumber, sequenceNumber));
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}
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// sending opus data.
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int size = data.bytesLeft();
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trackOutput.sampleData(data, size);
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long timeUs = toSampleTimeUs(startTimeOffsetUs, timestamp, firstReceivedTimestamp);
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trackOutput.sampleMetadata(
118+
timeUs, C.BUFFER_FLAG_KEY_FRAME, size, /* offset*/ 0, /* cryptoData*/ null);
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}
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previousSequenceNumber = sequenceNumber;
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}
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@Override
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public void seek(long nextRtpTimestamp, long timeUs) {
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firstReceivedTimestamp = nextRtpTimestamp;
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startTimeOffsetUs = timeUs;
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}
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// Internal methods.
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/**
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* Validates the OPUS ID Header at {@code data}'s current position, throws {@link
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* IllegalArgumentException} if the header is invalid.
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*
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* <p>{@code data}'s position does not change after returning.
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*/
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private static void validateOpusIdHeader(ParsableByteArray data) {
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int currPosition = data.getPosition();
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int sampleSize = data.limit();
140+
checkArgument(sampleSize > 18, "ID Header has insufficient data");
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String header = data.readString(8);
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// Identification header RFC7845 Section 5.1.
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checkArgument(header.equals("OpusHead"), "ID Header missing");
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checkArgument(data.readUnsignedByte() == 1, "version number must always be 1");
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data.setPosition(currPosition);
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}
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/** Returns the correct sample time from RTP timestamp, accounting for the OPUS sampling rate. */
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private static long toSampleTimeUs(
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long startTimeOffsetUs, long rtpTimestamp, long firstReceivedRtpTimestamp) {
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return startTimeOffsetUs
152+
+ Util.scaleLargeTimestamp(
153+
rtpTimestamp - firstReceivedRtpTimestamp,
154+
/* multiplier= */ C.MICROS_PER_SECOND,
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/* divisor= */ MEDIA_CLOCK_FREQUENCY);
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}
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}

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