1// Copyright (C) 2024 The Qt Company Ltd.
2// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
3
4#include "qaudiobufferinput.h"
5#include "qplatformaudiobufferinput_p.h"
6#include "qmediainputencoderinterface_p.h"
7#include "qmediaframeinput_p.h"
8
9QT_BEGIN_NAMESPACE
10
11class QAudioBufferInputPrivate : public QMediaFrameInputPrivate
12{
13public:
14 QAudioBufferInputPrivate(QAudioBufferInput *q) : q(q) { }
15
16 bool sendAudioBuffer(const QAudioBuffer &audioBuffer)
17 {
18 return sendMediaFrame(
19 sender: [&]() { emit m_platfromAudioBufferInput->newAudioBuffer(buffer: audioBuffer); });
20 }
21
22 void initialize(const QAudioFormat &format = {})
23 {
24 m_platfromAudioBufferInput = std::make_unique<QPlatformAudioBufferInput>(args: format);
25 addUpdateSignal(sender: m_platfromAudioBufferInput.get(),
26 signal: &QPlatformAudioBufferInput::encoderUpdated);
27 }
28
29 void uninitialize()
30 {
31 m_platfromAudioBufferInput.reset();
32
33 if (captureSession())
34 captureSession()->setAudioBufferInput(nullptr);
35 }
36
37 QMediaCaptureSession *session() const { return m_captureSession; }
38
39 QPlatformAudioBufferInput *platfromAudioBufferInput() const
40 {
41 return m_platfromAudioBufferInput.get();
42 }
43
44private:
45 void updateCaptureSessionConnections(QMediaCaptureSession *prevSession,
46 QMediaCaptureSession *newSession) override
47 {
48 if (prevSession)
49 removeUpdateSignal(sender: prevSession, signal: &QMediaCaptureSession::audioOutputChanged);
50
51 if (newSession)
52 addUpdateSignal(sender: newSession, signal: &QMediaCaptureSession::audioOutputChanged);
53 }
54
55 bool checkIfCanSendMediaFrame() const override
56 {
57 if (auto encoderInterface = m_platfromAudioBufferInput->encoderInterface())
58 return encoderInterface->canPushFrame();
59
60 // Not implemented yet
61 // return captureSession()->audioOutput() != nullptr;
62 return false;
63 }
64
65 void emitReadyToSendMediaFrame() override { emit q->readyToSendAudioBuffer(); }
66
67private:
68 QAudioBufferInput *q = nullptr;
69 QMediaCaptureSession *m_captureSession = nullptr;
70 std::unique_ptr<QPlatformAudioBufferInput> m_platfromAudioBufferInput;
71};
72
73/*!
74 \class QAudioBufferInput
75 \inmodule QtMultimedia
76 \ingroup multimedia
77 \ingroup multimedia_audio
78 \since 6.8
79
80 \brief The QAudioBufferInput class is used for providing custom audio buffers
81 to \l QMediaRecorder through \l QMediaCaptureSession.
82
83 QAudioBufferInput is only supported with the FFmpeg backend.
84
85 Custom audio buffers can be recorded by connecting a \l QAudioBufferInput and a
86 \l QMediaRecorder to a \l QMediaCaptureSession. For a pull mode implementation,
87 call \l sendAudioBuffer() in response to the \l readyToSendAudioBuffer() signal.
88 In the snippet below this is done by connecting the signal to a slot in a custom
89 media generator class. The slot function emits another signal with a new audio
90 buffer, which is connected to \l sendAudioBuffer():
91
92 \snippet custommediainputsnippets/custommediainputsnippets.cpp QAudioBufferInput setup
93
94 Here's a minimal implementation of the slot function that provides audio buffers:
95
96 \snippet custommediainputsnippets/custommediainputsnippets.cpp nextAudioBuffer()
97
98 For more details see readyToSendAudioBuffer() and sendAudioBuffer().
99
100 \sa QMediaRecorder and QMediaCaptureSession.
101*/
102
103/*!
104 Constructs a new QAudioBufferInput object with \a parent.
105*/
106QAudioBufferInput::QAudioBufferInput(QObject *parent) : QAudioBufferInput({}, parent) { }
107
108/*!
109 Constructs a new QAudioBufferInput object with audio \a format and \a parent.
110
111 The specified \a format will work as a hint for the initialization of the matching
112 audio encoder upon invoking \l QMediaRecorder::record().
113 If the format is not specified or not valid, the audio encoder will be initialized
114 upon sending the first audio buffer.
115
116 We recommend specifying the format if you know in advance what kind of audio buffers
117 you're going to send.
118*/
119QAudioBufferInput::QAudioBufferInput(const QAudioFormat &format, QObject *parent)
120 : QObject(*new QAudioBufferInputPrivate(this), parent)
121{
122 Q_D(QAudioBufferInput);
123 d->initialize(format);
124}
125
126/*!
127 Destroys the object.
128 */
129QAudioBufferInput::~QAudioBufferInput()
130{
131 Q_D(QAudioBufferInput);
132 d->uninitialize();
133}
134
135/*!
136 Sends \l QAudioBuffer to \l QMediaRecorder through \l QMediaCaptureSession.
137
138 Returns \c true if the specified \a audioBuffer has been sent successfully
139 to the destination. Returns \c false, if the buffer hasn't been sent,
140 which can happen if the instance is not assigned to
141 \l QMediaCaptureSession, the session doesn't have a media recorder,
142 the media recorder is not started or its queue is full.
143 The \l readyToSendAudioBuffer() signal will be emitted as soon as
144 the destination is able to handle a new audio buffer.
145
146 Sending of an empty audio buffer is treated by \l QMediaRecorder
147 as an end of the input stream. QMediaRecorder stops the recording
148 automatically if \l QMediaRecorder::autoStop is \c true and
149 all the inputs have reported the end of the stream.
150*/
151bool QAudioBufferInput::sendAudioBuffer(const QAudioBuffer &audioBuffer)
152{
153 Q_D(QAudioBufferInput);
154 return d->sendAudioBuffer(audioBuffer);
155}
156
157/*!
158 Returns the audio format that was specified upon construction of the audio buffer input.
159*/
160QAudioFormat QAudioBufferInput::format() const
161{
162 Q_D(const QAudioBufferInput);
163 return d->platfromAudioBufferInput()->audioFormat();
164}
165
166/*!
167 Returns the capture session this audio buffer input is connected to, or
168 a \c nullptr if the audio buffer input is not connected to a capture session.
169
170 Use QMediaCaptureSession::setAudioBufferInput() to connect
171 the audio buffer input to a session.
172*/
173QMediaCaptureSession *QAudioBufferInput::captureSession() const
174{
175 Q_D(const QAudioBufferInput);
176 return d->captureSession();
177}
178
179void QAudioBufferInput::setCaptureSession(QMediaCaptureSession *captureSession)
180{
181 Q_D(QAudioBufferInput);
182 d->setCaptureSession(captureSession);
183}
184
185QPlatformAudioBufferInput *QAudioBufferInput::platformAudioBufferInput() const
186{
187 Q_D(const QAudioBufferInput);
188 return d->platfromAudioBufferInput();
189}
190
191/*!
192 \fn void QAudioBufferInput::readyToSendAudioBuffer()
193
194 Signals that a new audio buffer can be sent to the audio buffer input.
195 After receiving the signal, if you have audio date to be sent, invoke \l sendAudioBuffer
196 once or in a loop until it returns \c false.
197
198 \sa sendAudioBuffer()
199*/
200
201QT_END_NAMESPACE
202

source code of qtmultimedia/src/multimedia/audio/qaudiobufferinput.cpp