1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef PPAPI_CPP_AUDIO_H_ 6 #define PPAPI_CPP_AUDIO_H_ 7 8 #include "ppapi/c/pp_stdint.h" 9 #include "ppapi/c/ppb_audio.h" 10 #include "ppapi/cpp/audio_config.h" 11 #include "ppapi/cpp/resource.h" 12 13 /// @file 14 /// This file defines the API to create realtime stereo audio streaming 15 /// capabilities. 16 17 namespace pp { 18 19 class InstanceHandle; 20 21 /// An audio resource. Refer to the 22 /// <a href="/native-client/devguide/coding/audio">Audio</a> 23 /// chapter in the Developer's Guide for information on using this interface. 24 class Audio : public Resource { 25 public: 26 27 /// An empty constructor for an Audio resource. 28 Audio() {} 29 30 /// A constructor that creates an Audio resource. No sound will be heard 31 /// until StartPlayback() is called. The callback is called with the buffer 32 /// address and given user data whenever the buffer needs to be filled. 33 /// From within the callback, you should not call <code>PPB_Audio</code> 34 /// functions. The callback will be called on a different thread than the one 35 /// which created the interface. For performance-critical applications (such 36 /// as low-latency audio), the callback should avoid blocking or calling 37 /// functions that can obtain locks, such as malloc. The layout and the size 38 /// of the buffer passed to the audio callback will be determined by 39 /// the device configuration and is specified in the <code>AudioConfig</code> 40 /// documentation. 41 /// 42 /// @param[in] instance The instance with which this resource will be 43 /// associated. 44 // 45 /// @param[in] config An <code>AudioConfig</code> containing the audio config 46 /// resource. 47 // 48 /// @param[in] callback A <code>PPB_Audio_Callback</code> callback function 49 /// that the browser calls when it needs more samples to play. 50 // 51 /// @param[in] user_data A pointer to user data used in the callback function. 52 Audio(const InstanceHandle& instance, 53 const AudioConfig& config, 54 PPB_Audio_Callback callback, 55 void* user_data); 56 57 /// Getter function for returning the internal <code>PPB_AudioConfig</code> 58 /// struct. 59 /// 60 /// @return A mutable reference to the PPB_AudioConfig struct. 61 AudioConfig& config() { return config_; } 62 63 /// Getter function for returning the internal <code>PPB_AudioConfig</code> 64 /// struct. 65 /// 66 /// @return A const reference to the internal <code>PPB_AudioConfig</code> 67 /// struct. 68 const AudioConfig& config() const { return config_; } 69 70 /// StartPlayback() starts playback of audio. 71 /// 72 /// @return true if successful, otherwise false. 73 bool StartPlayback(); 74 75 /// StopPlayback stops playback of audio. 76 /// 77 /// @return true if successful, otherwise false. 78 bool StopPlayback(); 79 80 private: 81 AudioConfig config_; 82 }; 83 84 } // namespace pp 85 86 #endif // PPAPI_CPP_AUDIO_H_ 87 88
