Split AAC utils out of CodecSpecificDataUtil
PiperOrigin-RevId: 297823929
This commit is contained in:
andrewlewis
Oliver Woodman
parent
ffdc5805bd
commit
1ca9a061b1
@ -0,0 +1,340 @@
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/*
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* Copyright 2020 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.audio;
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import com.google.android.exoplayer2.C;
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import com.google.android.exoplayer2.ParserException;
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import com.google.android.exoplayer2.util.Assertions;
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import com.google.android.exoplayer2.util.Log;
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import com.google.android.exoplayer2.util.ParsableBitArray;
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/** Utility methods for handling AAC audio streams. */
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public final class AacUtil {
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private static final String TAG = "AacUtil";
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/** Holds sample format information for AAC audio. */
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public static final class Config {
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/** The sample rate in Hertz. */
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public final int sampleRateHz;
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/** The number of channels. */
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public final int channelCount;
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/** The RFC 6381 codecs string. */
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public final String codecs;
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private Config(int sampleRateHz, int channelCount, String codecs) {
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this.sampleRateHz = sampleRateHz;
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this.channelCount = channelCount;
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this.codecs = codecs;
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}
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}
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// Audio sample count constants assume the frameLengthFlag in the access unit is 0.
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/**
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* Number of raw audio samples that are produced per channel when decoding an AAC LC access unit.
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*/
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public static final int AAC_LC_AUDIO_SAMPLE_COUNT = 1024;
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/**
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* Number of raw audio samples that are produced per channel when decoding an AAC XHE access unit.
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*/
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public static final int AAC_XHE_AUDIO_SAMPLE_COUNT = AAC_LC_AUDIO_SAMPLE_COUNT;
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/**
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* Number of raw audio samples that are produced per channel when decoding an AAC HE access unit.
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*/
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public static final int AAC_HE_AUDIO_SAMPLE_COUNT = 2048;
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/**
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* Number of raw audio samples that are produced per channel when decoding an AAC LD access unit.
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*/
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public static final int AAC_LD_AUDIO_SAMPLE_COUNT = 512;
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private static final int AUDIO_SPECIFIC_CONFIG_FREQUENCY_INDEX_ARBITRARY = 0xF;
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private static final int[] AUDIO_SPECIFIC_CONFIG_SAMPLING_RATE_TABLE =
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new int[] {
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96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050, 16000, 12000, 11025, 8000, 7350
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};
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private static final int AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID = -1;
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/**
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* In the channel configurations below, <A> indicates a single channel element; (A, B)
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* indicates a channel pair element; and [A] indicates a low-frequency effects element. The
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* speaker mapping short forms used are:
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*
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* <ul>
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* <li>FC: front center
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* <li>BC: back center
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* <li>FL/FR: front left/right
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* <li>FCL/FCR: front center left/right
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* <li>FTL/FTR: front top left/right
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* <li>SL/SR: back surround left/right
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* <li>BL/BR: back left/right
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* <li>LFE: low frequency effects
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* </ul>
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*/
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private static final int[] AUDIO_SPECIFIC_CONFIG_CHANNEL_COUNT_TABLE =
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new int[] {
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0,
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1, /* mono: <FC> */
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2, /* stereo: (FL, FR) */
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3, /* 3.0: <FC>, (FL, FR) */
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4, /* 4.0: <FC>, (FL, FR), <BC> */
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5, /* 5.0 back: <FC>, (FL, FR), (SL, SR) */
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6, /* 5.1 back: <FC>, (FL, FR), (SL, SR), <BC>, [LFE] */
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8, /* 7.1 wide back: <FC>, (FCL, FCR), (FL, FR), (SL, SR), [LFE] */
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AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID,
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AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID,
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AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID,
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7, /* 6.1: <FC>, (FL, FR), (SL, SR), <RC>, [LFE] */
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8, /* 7.1: <FC>, (FL, FR), (SL, SR), (BL, BR), [LFE] */
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AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID,
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8, /* 7.1 top: <FC>, (FL, FR), (SL, SR), [LFE], (FTL, FTR) */
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AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID
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};
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/**
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* Prefix for the RFC 6381 codecs string for AAC formats. To form a full codecs string, suffix the
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* decimal AudioObjectType.
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*/
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private static final String CODECS_STRING_PREFIX = "mp4a.40.";
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// Advanced Audio Coding Low-Complexity profile.
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private static final int AUDIO_OBJECT_TYPE_AAC_LC = 2;
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// Spectral Band Replication.
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private static final int AUDIO_OBJECT_TYPE_AAC_SBR = 5;
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// Error Resilient Bit-Sliced Arithmetic Coding.
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private static final int AUDIO_OBJECT_TYPE_AAC_ER_BSAC = 22;
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// Enhanced low delay.
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private static final int AUDIO_OBJECT_TYPE_AAC_ELD = 23;
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// Parametric Stereo.
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private static final int AUDIO_OBJECT_TYPE_AAC_PS = 29;
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// Escape code for extended audio object types.
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private static final int AUDIO_OBJECT_TYPE_ESCAPE = 31;
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// Extended high efficiency.
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private static final int AUDIO_OBJECT_TYPE_AAC_XHE = 42;
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/**
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* Parses an AAC AudioSpecificConfig, as defined in ISO 14496-3 1.6.2.1
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*
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* @param audioSpecificConfig A byte array containing the AudioSpecificConfig to parse.
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* @return The parsed configuration.
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* @throws ParserException If the AudioSpecificConfig cannot be parsed as it's not supported.
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*/
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public static Config parseAudioSpecificConfig(byte[] audioSpecificConfig) throws ParserException {
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return parseAudioSpecificConfig(
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new ParsableBitArray(audioSpecificConfig), /* forceReadToEnd= */ false);
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}
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/**
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* Parses an AAC AudioSpecificConfig, as defined in ISO 14496-3 1.6.2.1
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*
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* @param bitArray A {@link ParsableBitArray} containing the AudioSpecificConfig to parse. The
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* position is advanced to the end of the AudioSpecificConfig.
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* @param forceReadToEnd Whether the entire AudioSpecificConfig should be read. Required for
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* knowing the length of the configuration payload.
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* @return The parsed configuration.
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* @throws ParserException If the AudioSpecificConfig cannot be parsed as it's not supported.
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*/
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public static Config parseAudioSpecificConfig(ParsableBitArray bitArray, boolean forceReadToEnd)
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throws ParserException {
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int audioObjectType = getAudioObjectType(bitArray);
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int sampleRateHz = getSamplingFrequency(bitArray);
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int channelConfiguration = bitArray.readBits(4);
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String codecs = CODECS_STRING_PREFIX + audioObjectType;
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if (audioObjectType == AUDIO_OBJECT_TYPE_AAC_SBR
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|| audioObjectType == AUDIO_OBJECT_TYPE_AAC_PS) {
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// For an AAC bitstream using spectral band replication (SBR) or parametric stereo (PS) with
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// explicit signaling, we return the extension sampling frequency as the sample rate of the
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// content; this is identical to the sample rate of the decoded output but may differ from
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// the sample rate set above.
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// Use the extensionSamplingFrequencyIndex.
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sampleRateHz = getSamplingFrequency(bitArray);
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audioObjectType = getAudioObjectType(bitArray);
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if (audioObjectType == AUDIO_OBJECT_TYPE_AAC_ER_BSAC) {
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// Use the extensionChannelConfiguration.
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channelConfiguration = bitArray.readBits(4);
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}
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}
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if (forceReadToEnd) {
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switch (audioObjectType) {
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case 1:
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case 2:
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case 3:
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case 4:
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case 6:
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case 7:
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case 17:
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case 19:
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case 20:
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case 21:
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case 22:
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case 23:
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parseGaSpecificConfig(bitArray, audioObjectType, channelConfiguration);
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break;
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default:
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throw new ParserException("Unsupported audio object type: " + audioObjectType);
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}
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switch (audioObjectType) {
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case 17:
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case 19:
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case 20:
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case 21:
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case 22:
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case 23:
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int epConfig = bitArray.readBits(2);
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if (epConfig == 2 || epConfig == 3) {
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throw new ParserException("Unsupported epConfig: " + epConfig);
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}
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break;
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default:
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break;
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}
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}
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// For supported containers, bits_to_decode() is always 0.
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int channelCount = AUDIO_SPECIFIC_CONFIG_CHANNEL_COUNT_TABLE[channelConfiguration];
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Assertions.checkArgument(channelCount != AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID);
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return new Config(sampleRateHz, channelCount, codecs);
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}
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/**
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* Builds a simple AAC LC AudioSpecificConfig, as defined in ISO 14496-3 1.6.2.1
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*
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* @param sampleRate The sample rate in Hz.
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* @param channelCount The channel count.
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* @return The AudioSpecificConfig.
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*/
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public static byte[] buildAacLcAudioSpecificConfig(int sampleRate, int channelCount) {
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int sampleRateIndex = C.INDEX_UNSET;
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for (int i = 0; i < AUDIO_SPECIFIC_CONFIG_SAMPLING_RATE_TABLE.length; ++i) {
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if (sampleRate == AUDIO_SPECIFIC_CONFIG_SAMPLING_RATE_TABLE[i]) {
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sampleRateIndex = i;
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}
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}
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int channelConfig = C.INDEX_UNSET;
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for (int i = 0; i < AUDIO_SPECIFIC_CONFIG_CHANNEL_COUNT_TABLE.length; ++i) {
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if (channelCount == AUDIO_SPECIFIC_CONFIG_CHANNEL_COUNT_TABLE[i]) {
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channelConfig = i;
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}
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}
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if (sampleRate == C.INDEX_UNSET || channelConfig == C.INDEX_UNSET) {
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throw new IllegalArgumentException(
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"Invalid sample rate or number of channels: " + sampleRate + ", " + channelCount);
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}
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return buildAudioSpecificConfig(AUDIO_OBJECT_TYPE_AAC_LC, sampleRateIndex, channelConfig);
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}
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/**
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* Builds a simple AudioSpecificConfig, as defined in ISO 14496-3 1.6.2.1
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*
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* @param audioObjectType The audio object type.
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* @param sampleRateIndex The sample rate index.
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* @param channelConfig The channel configuration.
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* @return The AudioSpecificConfig.
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*/
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public static byte[] buildAudioSpecificConfig(
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int audioObjectType, int sampleRateIndex, int channelConfig) {
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byte[] specificConfig = new byte[2];
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specificConfig[0] = (byte) (((audioObjectType << 3) & 0xF8) | ((sampleRateIndex >> 1) & 0x07));
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specificConfig[1] = (byte) (((sampleRateIndex << 7) & 0x80) | ((channelConfig << 3) & 0x78));
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return specificConfig;
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}
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/** Returns the encoding for a given AAC audio object type. */
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@C.Encoding
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public static int getEncodingForAudioObjectType(int audioObjectType) {
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switch (audioObjectType) {
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case AUDIO_OBJECT_TYPE_AAC_LC:
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return C.ENCODING_AAC_LC;
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case AUDIO_OBJECT_TYPE_AAC_SBR:
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return C.ENCODING_AAC_HE_V1;
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case AUDIO_OBJECT_TYPE_AAC_PS:
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return C.ENCODING_AAC_HE_V2;
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case AUDIO_OBJECT_TYPE_AAC_XHE:
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return C.ENCODING_AAC_XHE;
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case AUDIO_OBJECT_TYPE_AAC_ELD:
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return C.ENCODING_AAC_ELD;
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default:
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return C.ENCODING_INVALID;
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}
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}
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/**
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* Returns the AAC audio object type as specified in 14496-3 (2005) Table 1.14.
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*
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* @param bitArray The bit array containing the audio specific configuration.
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* @return The audio object type.
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*/
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private static int getAudioObjectType(ParsableBitArray bitArray) {
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int audioObjectType = bitArray.readBits(5);
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if (audioObjectType == AUDIO_OBJECT_TYPE_ESCAPE) {
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audioObjectType = 32 + bitArray.readBits(6);
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}
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return audioObjectType;
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}
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/**
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* Returns the AAC sampling frequency (or extension sampling frequency) as specified in 14496-3
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* (2005) Table 1.13.
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*
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* @param bitArray The bit array containing the audio specific configuration.
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* @return The sampling frequency.
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*/
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private static int getSamplingFrequency(ParsableBitArray bitArray) {
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int samplingFrequency;
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int frequencyIndex = bitArray.readBits(4);
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if (frequencyIndex == AUDIO_SPECIFIC_CONFIG_FREQUENCY_INDEX_ARBITRARY) {
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samplingFrequency = bitArray.readBits(24);
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} else {
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Assertions.checkArgument(frequencyIndex < 13);
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samplingFrequency = AUDIO_SPECIFIC_CONFIG_SAMPLING_RATE_TABLE[frequencyIndex];
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}
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return samplingFrequency;
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}
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private static void parseGaSpecificConfig(
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ParsableBitArray bitArray, int audioObjectType, int channelConfiguration) {
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boolean frameLengthFlag = bitArray.readBit();
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if (frameLengthFlag) {
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Log.w(TAG, "Unexpected frameLengthFlag = 1");
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}
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boolean dependsOnCoreDecoder = bitArray.readBit();
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if (dependsOnCoreDecoder) {
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bitArray.skipBits(14); // coreCoderDelay.
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}
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boolean extensionFlag = bitArray.readBit();
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if (channelConfiguration == 0) {
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throw new UnsupportedOperationException(); // TODO: Implement programConfigElement();
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}
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if (audioObjectType == 6 || audioObjectType == 20) {
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bitArray.skipBits(3); // layerNr.
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}
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if (extensionFlag) {
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if (audioObjectType == 22) {
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bitArray.skipBits(16); // numOfSubFrame (5), layer_length(11).
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}
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if (audioObjectType == 17
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|| audioObjectType == 19
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|| audioObjectType == 20
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|| audioObjectType == 23) {
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// aacSectionDataResilienceFlag, aacScalefactorDataResilienceFlag,
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// aacSpectralDataResilienceFlag.
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bitArray.skipBits(3);
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}
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bitArray.skipBits(1); // extensionFlag3.
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}
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}
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private AacUtil() {}
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}
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@ -18,7 +18,6 @@ package com.google.android.exoplayer2.util;
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import android.util.Pair;
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import androidx.annotation.Nullable;
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import com.google.android.exoplayer2.C;
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import com.google.android.exoplayer2.ParserException;
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import java.util.ArrayList;
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import java.util.Collections;
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import java.util.List;
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@ -26,253 +25,8 @@ import java.util.List;
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/** Provides utilities for handling various types of codec-specific data. */
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public final class CodecSpecificDataUtil {
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private static final String TAG = "CodecSpecificDataUtil";
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/** Holds sample format information for AAC audio. */
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public static final class AacConfig {
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/** The sample rate in Hertz. */
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public final int sampleRateHz;
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/** The number of channels. */
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public final int channelCount;
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/** The RFC 6381 codecs string. */
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public final String codecs;
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private AacConfig(int sampleRateHz, int channelCount, String codecs) {
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this.sampleRateHz = sampleRateHz;
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this.channelCount = channelCount;
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this.codecs = codecs;
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}
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}
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// AAC audio sample count constants assume the frameLengthFlag in the access unit is 0.
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/**
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* Number of raw audio samples that are produced per channel when decoding an AAC LC access unit.
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*/
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public static final int AAC_LC_AUDIO_SAMPLE_COUNT = 1024;
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/**
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* Number of raw audio samples that are produced per channel when decoding an AAC XHE access unit.
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*/
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public static final int AAC_XHE_AUDIO_SAMPLE_COUNT = AAC_LC_AUDIO_SAMPLE_COUNT;
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/**
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* Number of raw audio samples that are produced per channel when decoding an AAC HE access unit.
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*/
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public static final int AAC_HE_AUDIO_SAMPLE_COUNT = 2048;
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/**
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* Number of raw audio samples that are produced per channel when decoding an AAC LD access unit.
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*/
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public static final int AAC_LD_AUDIO_SAMPLE_COUNT = 512;
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private static final byte[] NAL_START_CODE = new byte[] {0, 0, 0, 1};
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private static final int AUDIO_SPECIFIC_CONFIG_FREQUENCY_INDEX_ARBITRARY = 0xF;
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private static final int[] AUDIO_SPECIFIC_CONFIG_SAMPLING_RATE_TABLE = new int[] {
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96000, 88200, 64000, 48000, 44100, 32000, 24000, 22050, 16000, 12000, 11025, 8000, 7350
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};
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private static final int AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID = -1;
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/**
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* In the channel configurations below, <A> indicates a single channel element; (A, B) indicates a
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* channel pair element; and [A] indicates a low-frequency effects element.
|
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* The speaker mapping short forms used are:
|
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* - FC: front center
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* - BC: back center
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* - FL/FR: front left/right
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* - FCL/FCR: front center left/right
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* - FTL/FTR: front top left/right
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* - SL/SR: back surround left/right
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* - BL/BR: back left/right
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* - LFE: low frequency effects
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*/
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private static final int[] AUDIO_SPECIFIC_CONFIG_CHANNEL_COUNT_TABLE =
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new int[] {
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0,
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1, /* mono: <FC> */
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2, /* stereo: (FL, FR) */
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3, /* 3.0: <FC>, (FL, FR) */
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4, /* 4.0: <FC>, (FL, FR), <BC> */
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5, /* 5.0 back: <FC>, (FL, FR), (SL, SR) */
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6, /* 5.1 back: <FC>, (FL, FR), (SL, SR), <BC>, [LFE] */
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8, /* 7.1 wide back: <FC>, (FCL, FCR), (FL, FR), (SL, SR), [LFE] */
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AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID,
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AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID,
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AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID,
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||||
7, /* 6.1: <FC>, (FL, FR), (SL, SR), <RC>, [LFE] */
|
||||
8, /* 7.1: <FC>, (FL, FR), (SL, SR), (BL, BR), [LFE] */
|
||||
AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID,
|
||||
8, /* 7.1 top: <FC>, (FL, FR), (SL, SR), [LFE], (FTL, FTR) */
|
||||
AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID
|
||||
};
|
||||
|
||||
/**
|
||||
* Prefix for the RFC 6381 codecs string for AAC formats. To form a full codecs string, suffix the
|
||||
* decimal AudioObjectType.
|
||||
*/
|
||||
private static final String AAC_CODECS_STRING_PREFIX = "mp4a.40.";
|
||||
|
||||
// Advanced Audio Coding Low-Complexity profile.
|
||||
private static final int AUDIO_OBJECT_TYPE_AAC_LC = 2;
|
||||
// Spectral Band Replication.
|
||||
private static final int AUDIO_OBJECT_TYPE_AAC_SBR = 5;
|
||||
// Error Resilient Bit-Sliced Arithmetic Coding.
|
||||
private static final int AUDIO_OBJECT_TYPE_AAC_ER_BSAC = 22;
|
||||
// Enhanced low delay.
|
||||
private static final int AUDIO_OBJECT_TYPE_AAC_ELD = 23;
|
||||
// Parametric Stereo.
|
||||
private static final int AUDIO_OBJECT_TYPE_AAC_PS = 29;
|
||||
// Escape code for extended audio object types.
|
||||
private static final int AUDIO_OBJECT_TYPE_ESCAPE = 31;
|
||||
// Extended high efficiency.
|
||||
private static final int AUDIO_OBJECT_TYPE_AAC_XHE = 42;
|
||||
|
||||
private CodecSpecificDataUtil() {}
|
||||
|
||||
/**
|
||||
* Parses an AAC AudioSpecificConfig, as defined in ISO 14496-3 1.6.2.1
|
||||
*
|
||||
* @param audioSpecificConfig A byte array containing the AudioSpecificConfig to parse.
|
||||
* @return The parsed configuration.
|
||||
* @throws ParserException If the AudioSpecificConfig cannot be parsed as it's not supported.
|
||||
*/
|
||||
public static AacConfig parseAacAudioSpecificConfig(byte[] audioSpecificConfig)
|
||||
throws ParserException {
|
||||
return parseAacAudioSpecificConfig(
|
||||
new ParsableBitArray(audioSpecificConfig), /* forceReadToEnd= */ false);
|
||||
}
|
||||
|
||||
/**
|
||||
* Parses an AAC AudioSpecificConfig, as defined in ISO 14496-3 1.6.2.1
|
||||
*
|
||||
* @param bitArray A {@link ParsableBitArray} containing the AudioSpecificConfig to parse. The
|
||||
* position is advanced to the end of the AudioSpecificConfig.
|
||||
* @param forceReadToEnd Whether the entire AudioSpecificConfig should be read. Required for
|
||||
* knowing the length of the configuration payload.
|
||||
* @return The parsed configuration.
|
||||
* @throws ParserException If the AudioSpecificConfig cannot be parsed as it's not supported.
|
||||
*/
|
||||
public static AacConfig parseAacAudioSpecificConfig(
|
||||
ParsableBitArray bitArray, boolean forceReadToEnd) throws ParserException {
|
||||
int audioObjectType = getAacAudioObjectType(bitArray);
|
||||
int sampleRateHz = getAacSamplingFrequency(bitArray);
|
||||
int channelConfiguration = bitArray.readBits(4);
|
||||
String codecs = AAC_CODECS_STRING_PREFIX + audioObjectType;
|
||||
if (audioObjectType == AUDIO_OBJECT_TYPE_AAC_SBR
|
||||
|| audioObjectType == AUDIO_OBJECT_TYPE_AAC_PS) {
|
||||
// For an AAC bitstream using spectral band replication (SBR) or parametric stereo (PS) with
|
||||
// explicit signaling, we return the extension sampling frequency as the sample rate of the
|
||||
// content; this is identical to the sample rate of the decoded output but may differ from
|
||||
// the sample rate set above.
|
||||
// Use the extensionSamplingFrequencyIndex.
|
||||
sampleRateHz = getAacSamplingFrequency(bitArray);
|
||||
audioObjectType = getAacAudioObjectType(bitArray);
|
||||
if (audioObjectType == AUDIO_OBJECT_TYPE_AAC_ER_BSAC) {
|
||||
// Use the extensionChannelConfiguration.
|
||||
channelConfiguration = bitArray.readBits(4);
|
||||
}
|
||||
}
|
||||
|
||||
if (forceReadToEnd) {
|
||||
switch (audioObjectType) {
|
||||
case 1:
|
||||
case 2:
|
||||
case 3:
|
||||
case 4:
|
||||
case 6:
|
||||
case 7:
|
||||
case 17:
|
||||
case 19:
|
||||
case 20:
|
||||
case 21:
|
||||
case 22:
|
||||
case 23:
|
||||
parseGaSpecificConfig(bitArray, audioObjectType, channelConfiguration);
|
||||
break;
|
||||
default:
|
||||
throw new ParserException("Unsupported audio object type: " + audioObjectType);
|
||||
}
|
||||
switch (audioObjectType) {
|
||||
case 17:
|
||||
case 19:
|
||||
case 20:
|
||||
case 21:
|
||||
case 22:
|
||||
case 23:
|
||||
int epConfig = bitArray.readBits(2);
|
||||
if (epConfig == 2 || epConfig == 3) {
|
||||
throw new ParserException("Unsupported epConfig: " + epConfig);
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
// For supported containers, bits_to_decode() is always 0.
|
||||
int channelCount = AUDIO_SPECIFIC_CONFIG_CHANNEL_COUNT_TABLE[channelConfiguration];
|
||||
Assertions.checkArgument(channelCount != AUDIO_SPECIFIC_CONFIG_CHANNEL_CONFIGURATION_INVALID);
|
||||
return new AacConfig(sampleRateHz, channelCount, codecs);
|
||||
}
|
||||
|
||||
/**
|
||||
* Builds a simple HE-AAC LC AudioSpecificConfig, as defined in ISO 14496-3 1.6.2.1
|
||||
*
|
||||
* @param sampleRate The sample rate in Hz.
|
||||
* @param channelCount The channel count.
|
||||
* @return The AudioSpecificConfig.
|
||||
*/
|
||||
public static byte[] buildAacLcAudioSpecificConfig(int sampleRate, int channelCount) {
|
||||
int sampleRateIndex = C.INDEX_UNSET;
|
||||
for (int i = 0; i < AUDIO_SPECIFIC_CONFIG_SAMPLING_RATE_TABLE.length; ++i) {
|
||||
if (sampleRate == AUDIO_SPECIFIC_CONFIG_SAMPLING_RATE_TABLE[i]) {
|
||||
sampleRateIndex = i;
|
||||
}
|
||||
}
|
||||
int channelConfig = C.INDEX_UNSET;
|
||||
for (int i = 0; i < AUDIO_SPECIFIC_CONFIG_CHANNEL_COUNT_TABLE.length; ++i) {
|
||||
if (channelCount == AUDIO_SPECIFIC_CONFIG_CHANNEL_COUNT_TABLE[i]) {
|
||||
channelConfig = i;
|
||||
}
|
||||
}
|
||||
if (sampleRate == C.INDEX_UNSET || channelConfig == C.INDEX_UNSET) {
|
||||
throw new IllegalArgumentException(
|
||||
"Invalid sample rate or number of channels: " + sampleRate + ", " + channelCount);
|
||||
}
|
||||
return buildAacAudioSpecificConfig(AUDIO_OBJECT_TYPE_AAC_LC, sampleRateIndex, channelConfig);
|
||||
}
|
||||
|
||||
/**
|
||||
* Builds a simple AudioSpecificConfig, as defined in ISO 14496-3 1.6.2.1
|
||||
*
|
||||
* @param audioObjectType The audio object type.
|
||||
* @param sampleRateIndex The sample rate index.
|
||||
* @param channelConfig The channel configuration.
|
||||
* @return The AudioSpecificConfig.
|
||||
*/
|
||||
public static byte[] buildAacAudioSpecificConfig(int audioObjectType, int sampleRateIndex,
|
||||
int channelConfig) {
|
||||
byte[] specificConfig = new byte[2];
|
||||
specificConfig[0] = (byte) (((audioObjectType << 3) & 0xF8) | ((sampleRateIndex >> 1) & 0x07));
|
||||
specificConfig[1] = (byte) (((sampleRateIndex << 7) & 0x80) | ((channelConfig << 3) & 0x78));
|
||||
return specificConfig;
|
||||
}
|
||||
|
||||
/** Returns the encoding for a given AAC audio object type. */
|
||||
@C.Encoding
|
||||
public static int getEncodingForAacAudioObjectType(int audioObjectType) {
|
||||
switch (audioObjectType) {
|
||||
case AUDIO_OBJECT_TYPE_AAC_LC:
|
||||
return C.ENCODING_AAC_LC;
|
||||
case AUDIO_OBJECT_TYPE_AAC_SBR:
|
||||
return C.ENCODING_AAC_HE_V1;
|
||||
case AUDIO_OBJECT_TYPE_AAC_PS:
|
||||
return C.ENCODING_AAC_HE_V2;
|
||||
case AUDIO_OBJECT_TYPE_AAC_XHE:
|
||||
return C.ENCODING_AAC_XHE;
|
||||
case AUDIO_OBJECT_TYPE_AAC_ELD:
|
||||
return C.ENCODING_AAC_ELD;
|
||||
default:
|
||||
return C.ENCODING_INVALID;
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Parses an ALAC AudioSpecificConfig (i.e. an <a
|
||||
* href="https://github.com/macosforge/alac/blob/master/ALACMagicCookieDescription.txt">ALACSpecificConfig</a>).
|
||||
@ -414,67 +168,5 @@ public final class CodecSpecificDataUtil {
|
||||
return true;
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the AAC audio object type as specified in 14496-3 (2005) Table 1.14.
|
||||
*
|
||||
* @param bitArray The bit array containing the audio specific configuration.
|
||||
* @return The audio object type.
|
||||
*/
|
||||
private static int getAacAudioObjectType(ParsableBitArray bitArray) {
|
||||
int audioObjectType = bitArray.readBits(5);
|
||||
if (audioObjectType == AUDIO_OBJECT_TYPE_ESCAPE) {
|
||||
audioObjectType = 32 + bitArray.readBits(6);
|
||||
}
|
||||
return audioObjectType;
|
||||
}
|
||||
|
||||
/**
|
||||
* Returns the AAC sampling frequency (or extension sampling frequency) as specified in 14496-3
|
||||
* (2005) Table 1.13.
|
||||
*
|
||||
* @param bitArray The bit array containing the audio specific configuration.
|
||||
* @return The sampling frequency.
|
||||
*/
|
||||
private static int getAacSamplingFrequency(ParsableBitArray bitArray) {
|
||||
int samplingFrequency;
|
||||
int frequencyIndex = bitArray.readBits(4);
|
||||
if (frequencyIndex == AUDIO_SPECIFIC_CONFIG_FREQUENCY_INDEX_ARBITRARY) {
|
||||
samplingFrequency = bitArray.readBits(24);
|
||||
} else {
|
||||
Assertions.checkArgument(frequencyIndex < 13);
|
||||
samplingFrequency = AUDIO_SPECIFIC_CONFIG_SAMPLING_RATE_TABLE[frequencyIndex];
|
||||
}
|
||||
return samplingFrequency;
|
||||
}
|
||||
|
||||
private static void parseGaSpecificConfig(ParsableBitArray bitArray, int audioObjectType,
|
||||
int channelConfiguration) {
|
||||
boolean frameLengthFlag = bitArray.readBit();
|
||||
if (frameLengthFlag) {
|
||||
Log.w(TAG, "Unexpected AAC frameLengthFlag = 1");
|
||||
}
|
||||
boolean dependsOnCoreDecoder = bitArray.readBit();
|
||||
if (dependsOnCoreDecoder) {
|
||||
bitArray.skipBits(14); // coreCoderDelay.
|
||||
}
|
||||
boolean extensionFlag = bitArray.readBit();
|
||||
if (channelConfiguration == 0) {
|
||||
throw new UnsupportedOperationException(); // TODO: Implement programConfigElement();
|
||||
}
|
||||
if (audioObjectType == 6 || audioObjectType == 20) {
|
||||
bitArray.skipBits(3); // layerNr.
|
||||
}
|
||||
if (extensionFlag) {
|
||||
if (audioObjectType == 22) {
|
||||
bitArray.skipBits(16); // numOfSubFrame (5), layer_length(11).
|
||||
}
|
||||
if (audioObjectType == 17 || audioObjectType == 19 || audioObjectType == 20
|
||||
|| audioObjectType == 23) {
|
||||
// aacSectionDataResilienceFlag, aacScalefactorDataResilienceFlag,
|
||||
// aacSpectralDataResilienceFlag.
|
||||
bitArray.skipBits(3);
|
||||
}
|
||||
bitArray.skipBits(1); // extensionFlag3.
|
||||
}
|
||||
}
|
||||
private CodecSpecificDataUtil() {}
|
||||
}
|
||||
|
||||
@ -28,7 +28,6 @@ import com.google.android.exoplayer2.Format;
|
||||
import com.google.android.exoplayer2.PlaybackParameters;
|
||||
import com.google.android.exoplayer2.audio.AudioProcessor.UnhandledAudioFormatException;
|
||||
import com.google.android.exoplayer2.util.Assertions;
|
||||
import com.google.android.exoplayer2.util.CodecSpecificDataUtil;
|
||||
import com.google.android.exoplayer2.util.Log;
|
||||
import com.google.android.exoplayer2.util.Util;
|
||||
import java.nio.ByteBuffer;
|
||||
@ -1258,14 +1257,14 @@ public final class DefaultAudioSink implements AudioSink {
|
||||
case C.ENCODING_MP3:
|
||||
return MpegAudioUtil.parseMpegAudioFrameSampleCount(buffer.get(buffer.position()));
|
||||
case C.ENCODING_AAC_LC:
|
||||
return CodecSpecificDataUtil.AAC_LC_AUDIO_SAMPLE_COUNT;
|
||||
return AacUtil.AAC_LC_AUDIO_SAMPLE_COUNT;
|
||||
case C.ENCODING_AAC_HE_V1:
|
||||
case C.ENCODING_AAC_HE_V2:
|
||||
return CodecSpecificDataUtil.AAC_HE_AUDIO_SAMPLE_COUNT;
|
||||
return AacUtil.AAC_HE_AUDIO_SAMPLE_COUNT;
|
||||
case C.ENCODING_AAC_XHE:
|
||||
return CodecSpecificDataUtil.AAC_XHE_AUDIO_SAMPLE_COUNT;
|
||||
return AacUtil.AAC_XHE_AUDIO_SAMPLE_COUNT;
|
||||
case C.ENCODING_AAC_ELD:
|
||||
return CodecSpecificDataUtil.AAC_LD_AUDIO_SAMPLE_COUNT;
|
||||
return AacUtil.AAC_LD_AUDIO_SAMPLE_COUNT;
|
||||
case C.ENCODING_DTS:
|
||||
case C.ENCODING_DTS_HD:
|
||||
return DtsUtil.parseDtsAudioSampleCount(buffer);
|
||||
|
||||
@ -18,9 +18,8 @@ package com.google.android.exoplayer2.extractor.flv;
|
||||
import com.google.android.exoplayer2.C;
|
||||
import com.google.android.exoplayer2.Format;
|
||||
import com.google.android.exoplayer2.ParserException;
|
||||
import com.google.android.exoplayer2.audio.AacUtil;
|
||||
import com.google.android.exoplayer2.extractor.TrackOutput;
|
||||
import com.google.android.exoplayer2.util.CodecSpecificDataUtil;
|
||||
import com.google.android.exoplayer2.util.CodecSpecificDataUtil.AacConfig;
|
||||
import com.google.android.exoplayer2.util.MimeTypes;
|
||||
import com.google.android.exoplayer2.util.ParsableByteArray;
|
||||
import java.util.Collections;
|
||||
@ -109,8 +108,7 @@ import java.util.Collections;
|
||||
// Parse the sequence header.
|
||||
byte[] audioSpecificConfig = new byte[data.bytesLeft()];
|
||||
data.readBytes(audioSpecificConfig, 0, audioSpecificConfig.length);
|
||||
AacConfig aacConfig =
|
||||
CodecSpecificDataUtil.parseAacAudioSpecificConfig(audioSpecificConfig);
|
||||
AacUtil.Config aacConfig = AacUtil.parseAudioSpecificConfig(audioSpecificConfig);
|
||||
Format format =
|
||||
new Format.Builder()
|
||||
.setSampleMimeType(MimeTypes.AUDIO_AAC)
|
||||
|
||||
@ -22,6 +22,7 @@ import androidx.annotation.Nullable;
|
||||
import com.google.android.exoplayer2.C;
|
||||
import com.google.android.exoplayer2.Format;
|
||||
import com.google.android.exoplayer2.ParserException;
|
||||
import com.google.android.exoplayer2.audio.AacUtil;
|
||||
import com.google.android.exoplayer2.audio.Ac3Util;
|
||||
import com.google.android.exoplayer2.audio.Ac4Util;
|
||||
import com.google.android.exoplayer2.drm.DrmInitData;
|
||||
@ -29,7 +30,6 @@ import com.google.android.exoplayer2.extractor.GaplessInfoHolder;
|
||||
import com.google.android.exoplayer2.metadata.Metadata;
|
||||
import com.google.android.exoplayer2.util.Assertions;
|
||||
import com.google.android.exoplayer2.util.CodecSpecificDataUtil;
|
||||
import com.google.android.exoplayer2.util.CodecSpecificDataUtil.AacConfig;
|
||||
import com.google.android.exoplayer2.util.Log;
|
||||
import com.google.android.exoplayer2.util.MimeTypes;
|
||||
import com.google.android.exoplayer2.util.ParsableByteArray;
|
||||
@ -1184,8 +1184,7 @@ import org.checkerframework.checker.nullness.compatqual.NullableType;
|
||||
if (MimeTypes.AUDIO_AAC.equals(mimeType) && initializationData != null) {
|
||||
// Update sampleRate and channelCount from the AudioSpecificConfig initialization data,
|
||||
// which is more reliable. See [Internal: b/10903778].
|
||||
AacConfig aacConfig =
|
||||
CodecSpecificDataUtil.parseAacAudioSpecificConfig(initializationData);
|
||||
AacUtil.Config aacConfig = AacUtil.parseAudioSpecificConfig(initializationData);
|
||||
sampleRate = aacConfig.sampleRateHz;
|
||||
channelCount = aacConfig.channelCount;
|
||||
codecs = aacConfig.codecs;
|
||||
|
||||
@ -19,13 +19,12 @@ import androidx.annotation.Nullable;
|
||||
import com.google.android.exoplayer2.C;
|
||||
import com.google.android.exoplayer2.Format;
|
||||
import com.google.android.exoplayer2.ParserException;
|
||||
import com.google.android.exoplayer2.audio.AacUtil;
|
||||
import com.google.android.exoplayer2.extractor.DummyTrackOutput;
|
||||
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.CodecSpecificDataUtil;
|
||||
import com.google.android.exoplayer2.util.CodecSpecificDataUtil.AacConfig;
|
||||
import com.google.android.exoplayer2.util.Log;
|
||||
import com.google.android.exoplayer2.util.MimeTypes;
|
||||
import com.google.android.exoplayer2.util.ParsableBitArray;
|
||||
@ -467,9 +466,9 @@ public final class AdtsReader implements ElementaryStreamReader {
|
||||
int channelConfig = adtsScratch.readBits(3);
|
||||
|
||||
byte[] audioSpecificConfig =
|
||||
CodecSpecificDataUtil.buildAacAudioSpecificConfig(
|
||||
AacUtil.buildAudioSpecificConfig(
|
||||
audioObjectType, firstFrameSampleRateIndex, channelConfig);
|
||||
AacConfig aacConfig = CodecSpecificDataUtil.parseAacAudioSpecificConfig(audioSpecificConfig);
|
||||
AacUtil.Config aacConfig = AacUtil.parseAudioSpecificConfig(audioSpecificConfig);
|
||||
Format format =
|
||||
new Format.Builder()
|
||||
.setId(formatId)
|
||||
|
||||
@ -19,12 +19,11 @@ import androidx.annotation.Nullable;
|
||||
import com.google.android.exoplayer2.C;
|
||||
import com.google.android.exoplayer2.Format;
|
||||
import com.google.android.exoplayer2.ParserException;
|
||||
import com.google.android.exoplayer2.audio.AacUtil;
|
||||
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.CodecSpecificDataUtil;
|
||||
import com.google.android.exoplayer2.util.CodecSpecificDataUtil.AacConfig;
|
||||
import com.google.android.exoplayer2.util.MimeTypes;
|
||||
import com.google.android.exoplayer2.util.ParsableBitArray;
|
||||
import com.google.android.exoplayer2.util.ParsableByteArray;
|
||||
@ -273,8 +272,7 @@ public final class LatmReader implements ElementaryStreamReader {
|
||||
|
||||
private int parseAudioSpecificConfig(ParsableBitArray data) throws ParserException {
|
||||
int bitsLeft = data.bitsLeft();
|
||||
AacConfig config =
|
||||
CodecSpecificDataUtil.parseAacAudioSpecificConfig(data, /* forceReadToEnd= */ true);
|
||||
AacUtil.Config config = AacUtil.parseAudioSpecificConfig(data, /* forceReadToEnd= */ true);
|
||||
sampleRateHz = config.sampleRateHz;
|
||||
channelCount = config.channelCount;
|
||||
return bitsLeft - data.bitsLeft();
|
||||
|
||||
@ -23,6 +23,7 @@ import androidx.annotation.Nullable;
|
||||
import com.google.android.exoplayer2.C;
|
||||
import com.google.android.exoplayer2.Format;
|
||||
import com.google.android.exoplayer2.ParserException;
|
||||
import com.google.android.exoplayer2.audio.AacUtil;
|
||||
import com.google.android.exoplayer2.drm.DrmInitData;
|
||||
import com.google.android.exoplayer2.drm.DrmInitData.SchemeData;
|
||||
import com.google.android.exoplayer2.extractor.mp4.PsshAtomUtil;
|
||||
@ -687,7 +688,7 @@ public class SsManifestParser implements ParsingLoadable.Parser<SsManifest> {
|
||||
if (codecSpecificData.isEmpty() && MimeTypes.AUDIO_AAC.equals(sampleMimeType)) {
|
||||
codecSpecificData =
|
||||
Collections.singletonList(
|
||||
CodecSpecificDataUtil.buildAacLcAudioSpecificConfig(sampleRate, channelCount));
|
||||
AacUtil.buildAacLcAudioSpecificConfig(sampleRate, channelCount));
|
||||
}
|
||||
formatBuilder
|
||||
.setContainerMimeType(MimeTypes.AUDIO_MP4)
|
||||
|
||||
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Reference in New Issue
Block a user