1 /*
2  * Copyright 2015 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 /**
18  * Implements an API to be used by A2DP to do streaming of music over a media
19  * stream. This API provides mechanism to create and control playback of the
20  * media stream depending on the data bits coming from the remote device. The
21  * media stream is played over the default audio media stream type and hence
22  * volume control is handled entirely by the Audio Manager (which is also the
23  * original motivation for this solution.
24  *
25  * TODO: Once the AudioManager provides support for patching audio sources with
26  * volume control we should deprecate this file.
27  */
28 
29 /**
30  * Creates an audio track object and returns a void handle. Use this handle to
31  * the
32  * following functions.
33  *
34  * The ownership of the handle is maintained by the caller of this API and it
35  * should eventually be
36  * deleted using BtifAvrcpAudioTrackDelete (see below).
37  */
38 void* BtifAvrcpAudioTrackCreate(int trackFreq, int bitsPerSample,
39                                 int channelCount);
40 
41 /**
42  * Starts the audio track.
43  */
44 void BtifAvrcpAudioTrackStart(void* handle);
45 
46 /**
47  * Pauses the audio track.
48  */
49 void BtifAvrcpAudioTrackPause(void* handle);
50 
51 /**
52  * Sets audio track gain.
53  */
54 void BtifAvrcpSetAudioTrackGain(void* handle, float gain);
55 
56 /**
57  * Stop / Delete the audio track.
58  * Delete should usually be called stop.
59  */
60 void BtifAvrcpAudioTrackStop(void* handle);
61 void BtifAvrcpAudioTrackDelete(void* handle);
62 
63 /**
64  * Writes the audio track data to file.
65  *
66  * Used only for debugging.
67  */
68 int BtifAvrcpAudioTrackWriteData(void* handle, void* audioBuffer,
69                                  int bufferLength);
70