diff options
Diffstat (limited to 'voip/java')
-rw-r--r-- | voip/java/android/net/rtp/AudioGroup.java | 86 | ||||
-rw-r--r-- | voip/java/android/net/rtp/AudioStream.java | 4 |
2 files changed, 46 insertions, 44 deletions
diff --git a/voip/java/android/net/rtp/AudioGroup.java b/voip/java/android/net/rtp/AudioGroup.java index a6b54d8..20c8969 100644 --- a/voip/java/android/net/rtp/AudioGroup.java +++ b/voip/java/android/net/rtp/AudioGroup.java @@ -16,41 +16,47 @@ package android.net.rtp; +import android.media.AudioManager; + import java.util.HashMap; import java.util.Map; /** - * An AudioGroup acts as a router connected to the speaker, the microphone, and - * {@link AudioStream}s. Its execution loop consists of four steps. First, for - * each AudioStream not in {@link RtpStream#MODE_SEND_ONLY}, decodes its - * incoming packets and stores in its buffer. Then, if the microphone is - * enabled, processes the recorded audio and stores in its buffer. Third, if the - * speaker is enabled, mixes and playbacks buffers of all AudioStreams. Finally, - * for each AudioStream not in {@link RtpStream#MODE_RECEIVE_ONLY}, mixes all - * other buffers and sends back the encoded packets. An AudioGroup does nothing - * if there is no AudioStream in it. + * An AudioGroup is an audio hub for the speaker, the microphone, and + * {@link AudioStream}s. Each of these components can be logically turned on + * or off by calling {@link #setMode(int)} or {@link RtpStream#setMode(int)}. + * The AudioGroup will go through these components and process them one by one + * within its execution loop. The loop consists of four steps. First, for each + * AudioStream not in {@link RtpStream#MODE_SEND_ONLY}, decodes its incoming + * packets and stores in its buffer. Then, if the microphone is enabled, + * processes the recorded audio and stores in its buffer. Third, if the speaker + * is enabled, mixes all AudioStream buffers and plays back. Finally, for each + * AudioStream not in {@link RtpStream#MODE_RECEIVE_ONLY}, mixes all other + * buffers and sends back the encoded packets. An AudioGroup does nothing if + * there is no AudioStream in it. * * <p>Few things must be noticed before using these classes. The performance is * highly related to the system load and the network bandwidth. Usually a * simpler {@link AudioCodec} costs fewer CPU cycles but requires more network - * bandwidth, and vise versa. Using two AudioStreams at the same time not only - * doubles the load but also the bandwidth. The condition varies from one device - * to another, and developers must choose the right combination in order to get - * the best result. + * bandwidth, and vise versa. Using two AudioStreams at the same time doubles + * not only the load but also the bandwidth. The condition varies from one + * device to another, and developers should choose the right combination in + * order to get the best result.</p> * * <p>It is sometimes useful to keep multiple AudioGroups at the same time. For * example, a Voice over IP (VoIP) application might want to put a conference * call on hold in order to make a new call but still allow people in the - * previous call to talk to each other. This can be done easily using two + * conference call talking to each other. This can be done easily using two * AudioGroups, but there are some limitations. Since the speaker and the - * microphone are shared globally, only one AudioGroup is allowed to run in - * modes other than {@link #MODE_ON_HOLD}. In addition, before adding an - * AudioStream into an AudioGroup, one should always put all other AudioGroups - * into {@link #MODE_ON_HOLD}. That will make sure the audio driver correctly - * initialized.</p> + * microphone are globally shared resources, only one AudioGroup at a time is + * allowed to run in a mode other than {@link #MODE_ON_HOLD}. The others will + * be unable to acquire these resources and fail silently.</p> * * <p class="note">Using this class requires - * {@link android.Manifest.permission#RECORD_AUDIO} permission.</p> + * {@link android.Manifest.permission#RECORD_AUDIO} permission. Developers + * should set the audio mode to {@link AudioManager#MODE_IN_COMMUNICATION} + * using {@link AudioManager#setMode(int)} and change it back when none of + * the AudioGroups is in use.</p> * * @see AudioStream * @hide @@ -58,13 +64,13 @@ import java.util.Map; public class AudioGroup { /** * This mode is similar to {@link #MODE_NORMAL} except the speaker and - * the microphone are disabled. + * the microphone are both disabled. */ public static final int MODE_ON_HOLD = 0; /** * This mode is similar to {@link #MODE_NORMAL} except the microphone is - * muted. + * disabled. */ public static final int MODE_MUTED = 1; @@ -137,20 +143,18 @@ public class AudioGroup { private native void nativeSetMode(int mode); // Package-private method used by AudioStream.join(). - void add(AudioStream stream, AudioCodec codec, int dtmfType) { - synchronized (this) { - if (!mStreams.containsKey(stream)) { - try { - int socket = stream.dup(); - String codecSpec = String.format("%d %s %s", codec.type, - codec.rtpmap, codec.fmtp); - nativeAdd(stream.getMode(), socket, - stream.getRemoteAddress().getHostAddress(), - stream.getRemotePort(), codecSpec, dtmfType); - mStreams.put(stream, socket); - } catch (NullPointerException e) { - throw new IllegalStateException(e); - } + synchronized void add(AudioStream stream, AudioCodec codec, int dtmfType) { + if (!mStreams.containsKey(stream)) { + try { + int socket = stream.dup(); + String codecSpec = String.format("%d %s %s", codec.type, + codec.rtpmap, codec.fmtp); + nativeAdd(stream.getMode(), socket, + stream.getRemoteAddress().getHostAddress(), + stream.getRemotePort(), codecSpec, dtmfType); + mStreams.put(stream, socket); + } catch (NullPointerException e) { + throw new IllegalStateException(e); } } } @@ -159,12 +163,10 @@ public class AudioGroup { int remotePort, String codecSpec, int dtmfType); // Package-private method used by AudioStream.join(). - void remove(AudioStream stream) { - synchronized (this) { - Integer socket = mStreams.remove(stream); - if (socket != null) { - nativeRemove(socket); - } + synchronized void remove(AudioStream stream) { + Integer socket = mStreams.remove(stream); + if (socket != null) { + nativeRemove(socket); } } diff --git a/voip/java/android/net/rtp/AudioStream.java b/voip/java/android/net/rtp/AudioStream.java index 0edae6b..b45cc5e 100644 --- a/voip/java/android/net/rtp/AudioStream.java +++ b/voip/java/android/net/rtp/AudioStream.java @@ -27,8 +27,8 @@ import java.net.SocketException; * configured {@link AudioCodec}. On the other side, An {@link AudioGroup} * represents a local endpoint which mixes all the AudioStreams and optionally * interacts with the speaker and the microphone at the same time. The simplest - * usage includes one for each endpoints. For other combinations, users should - * be aware of the limitations described in {@link AudioGroup}. + * usage includes one for each endpoints. For other combinations, developers + * should be aware of the limitations described in {@link AudioGroup}. * * <p>An AudioStream becomes busy when it joins an AudioGroup. In this case most * of the setter methods are disabled. This is designed to ease the task of |