cef_audio_handler.h

// Copyright (c) 2019 Marshall A. Greenblatt. All rights reserved.
//
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// modification, are permitted provided that the following conditions are
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// ---------------------------------------------------------------------------
//
// The contents of this file must follow a specific format in order to
// support the CEF translator tool. See the translator.README.txt file in the
// tools directory for more information.
//

#ifndef CEF_INCLUDE_CEF_AUDIO_HANDLER_H_
#define CEF_INCLUDE_CEF_AUDIO_HANDLER_H_
#pragma once

#include "include/cef_base.h"
#include "include/cef_browser.h"

///
/// Implement this interface to handle audio events.
///
/*--cef(source=client)--*/
class CefAudioHandler : public virtual CefBaseRefCounted {
 public:
  typedef cef_channel_layout_t ChannelLayout;

  ///
  /// Called on the UI thread to allow configuration of audio stream parameters.
  /// Return true to proceed with audio stream capture, or false to cancel it.
  /// All members of |params| can optionally be configured here, but they are
  /// also pre-filled with some sensible defaults.
  ///
  /*--cef()--*/
  virtual bool GetAudioParameters(CefRefPtr<CefBrowser> browser,
                                  CefAudioParameters& params) {
    return true;
  }

  ///
  /// Called on a browser audio capture thread when the browser starts
  /// streaming audio. OnAudioStreamStopped will always be called after
  /// OnAudioStreamStarted; both methods may be called multiple times
  /// for the same browser. |params| contains the audio parameters like
  /// sample rate and channel layout. |channels| is the number of channels.
  ///
  /*--cef()--*/
  virtual void OnAudioStreamStarted(CefRefPtr<CefBrowser> browser,
                                    const CefAudioParameters& params,
                                    int channels) = 0;

  ///
  /// Called on the audio stream thread when a PCM packet is received for the
  /// stream. |data| is an array representing the raw PCM data as a floating
  /// point type, i.e. 4-byte value(s). |frames| is the number of frames in the
  /// PCM packet. |pts| is the presentation timestamp (in milliseconds since the
  /// Unix Epoch) and represents the time at which the decompressed packet
  /// should be presented to the user. Based on |frames| and the
  /// |channel_layout| value passed to OnAudioStreamStarted you can calculate
  /// the size of the |data| array in bytes.
  ///
  /*--cef()--*/
  virtual void OnAudioStreamPacket(CefRefPtr<CefBrowser> browser,
                                   const float** data,
                                   int frames,
                                   int64 pts) = 0;

  ///
  /// Called on the UI thread when the stream has stopped. OnAudioSteamStopped
  /// will always be called after OnAudioStreamStarted; both methods may be
  /// called multiple times for the same stream.
  ///
  /*--cef()--*/
  virtual void OnAudioStreamStopped(CefRefPtr<CefBrowser> browser) = 0;

  ///
  /// Called on the UI or audio stream thread when an error occurred. During the
  /// stream creation phase this callback will be called on the UI thread while
  /// in the capturing phase it will be called on the audio stream thread. The
  /// stream will be stopped immediately.
  ///
  /*--cef()--*/
  virtual void OnAudioStreamError(CefRefPtr<CefBrowser> browser,
                                  const CefString& message) = 0;
};

#endif  // CEF_INCLUDE_CEF_AUDIO_HANDLER_H_