198cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang/* 298cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * Copyright (C) 2010 The Android Open Source Project 398cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * 498cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * Licensed under the Apache License, Version 2.0 (the "License"); 598cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * you may not use this file except in compliance with the License. 698cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * You may obtain a copy of the License at 798cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * 898cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * http://www.apache.org/licenses/LICENSE-2.0 998cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * 1098cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * Unless required by applicable law or agreed to in writing, software 1198cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * distributed under the License is distributed on an "AS IS" BASIS, 1298cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 1398cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * See the License for the specific language governing permissions and 1498cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * limitations under the License. 1598cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang */ 1698cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang 1798cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wangpackage android.net.rtp; 1898cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang 197f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yehimport java.util.Arrays; 207f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh 217f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh/** 227f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * This class defines a collection of audio codecs to be used with 237f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * {@link AudioStream}s. Their parameters are designed to be exchanged using 247f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * Session Description Protocol (SDP). Most of the values listed here can be 257f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * found in RFC 3551, while others are described in separated standards. 267f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * 277f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * <p>Few simple configurations are defined as public static instances for the 287f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * convenience of direct uses. More complicated ones could be obtained using 297f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * {@link #getCodec(int, String, String)}. For example, one can use the 307f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * following snippet to create a mode-1-only AMR codec.</p> 317f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * <pre> 327f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * AudioCodec codec = AudioCodec.getCodec(100, "AMR/8000", "mode-set=1"); 337f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * </pre> 347f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * 357f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * @see AudioStream 367f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh */ 3798cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wangpublic class AudioCodec { 387f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh /** 397f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * The RTP payload type of the encoding. 407f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh */ 417f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh public final int type; 427f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh 437f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh /** 447f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * The encoding parameters to be used in the corresponding SDP attribute. 457f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh */ 467f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh public final String rtpmap; 477f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh 487f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh /** 497f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * The format parameters to be used in the corresponding SDP attribute. 507f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh */ 517f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh public final String fmtp; 527f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh 537f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh /** 547f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * G.711 u-law audio codec. 557f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh */ 567f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh public static final AudioCodec PCMU = new AudioCodec(0, "PCMU/8000", null); 577f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh 587f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh /** 597f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * G.711 a-law audio codec. 607f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh */ 617f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh public static final AudioCodec PCMA = new AudioCodec(8, "PCMA/8000", null); 6298cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang 6398cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang /** 647f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * GSM Full-Rate audio codec, also known as GSM-FR, GSM 06.10, GSM, or 657f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * simply FR. 6698cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang */ 677f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh public static final AudioCodec GSM = new AudioCodec(3, "GSM/8000", null); 687f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh 697f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh /** 707f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * GSM Enhanced Full-Rate audio codec, also known as GSM-EFR, GSM 06.60, or 717f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * simply EFR. 727f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh */ 737f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh public static final AudioCodec GSM_EFR = new AudioCodec(96, "GSM-EFR/8000", null); 747f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh 757f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh /** 767f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * Adaptive Multi-Rate narrowband audio codec, also known as AMR or AMR-NB. 777f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * Currently CRC, robust sorting, and interleaving are not supported. See 787f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * more details about these features in RFC 4867. 797f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh */ 807f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh public static final AudioCodec AMR = new AudioCodec(97, "AMR/8000", null); 817f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh 822437b7d03ce3c0c63ffe04e15a53174d15ee8479Chia-chi Yeh private static final AudioCodec[] sCodecs = {GSM_EFR, AMR, GSM, PCMU, PCMA}; 837f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh 847f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh private AudioCodec(int type, String rtpmap, String fmtp) { 857f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh this.type = type; 867f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh this.rtpmap = rtpmap; 877f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh this.fmtp = fmtp; 8898cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang } 8998cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang 9098cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang /** 917f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * Returns system supported audio codecs. 927f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh */ 937f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh public static AudioCodec[] getCodecs() { 947f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh return Arrays.copyOf(sCodecs, sCodecs.length); 957f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh } 967f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh 977f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh /** 987f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * Creates an AudioCodec according to the given configuration. 9998cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang * 1007f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * @param type The payload type of the encoding defined in RTP/AVP. 1017f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * @param rtpmap The encoding parameters specified in the corresponding SDP 1027f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * attribute, or null if it is not available. 1037f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * @param fmtp The format parameters specified in the corresponding SDP 1047f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * attribute, or null if it is not available. 1057f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh * @return The configured AudioCodec or {@code null} if it is not supported. 10698cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang */ 1077f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh public static AudioCodec getCodec(int type, String rtpmap, String fmtp) { 1087f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh if (type < 0 || type > 127) { 1097f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh return null; 11098cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang } 11198cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang 1127f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh AudioCodec hint = null; 1137f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh if (rtpmap != null) { 1147f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh String clue = rtpmap.trim().toUpperCase(); 1157f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh for (AudioCodec codec : sCodecs) { 1167f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh if (clue.startsWith(codec.rtpmap)) { 1177f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh String channels = clue.substring(codec.rtpmap.length()); 1187f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh if (channels.length() == 0 || channels.equals("/1")) { 1197f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh hint = codec; 1207f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh } 1217f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh break; 1227f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh } 1237f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh } 1247f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh } else if (type < 96) { 1257f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh for (AudioCodec codec : sCodecs) { 1267f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh if (type == codec.type) { 1277f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh hint = codec; 1287f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh rtpmap = codec.rtpmap; 1297f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh break; 1307f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh } 1317f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh } 1327f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh } 13398cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang 1347f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh if (hint == null) { 1357f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh return null; 1367f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh } 1377f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh if (hint == AMR && fmtp != null) { 1387f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh String clue = fmtp.toLowerCase(); 1397f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh if (clue.contains("crc=1") || clue.contains("robust-sorting=1") || 1407f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh clue.contains("interleaving=")) { 1417f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh return null; 1427f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh } 1437f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh } 1447f383063fafc54a41f91540a41bf987003fd2502Chia-chi Yeh return new AudioCodec(type, rtpmap, fmtp); 14598cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang } 14698cee0ce2354234e72bafb836864ec10a490ea4dChung-yih Wang} 147