Simplify lifetime management of QPlatformAudioResampler

QPlatformMediaIntegration creates various objects, and return them as
QMaybe<Type*>. This moves responsibility of ownership to the caller.

This patch makes the createAudioResampler function return the resampler
as QMaybe<std::unique_ptr<Type>> which simplifies lifetime management.

This introduces an asymmetry with other factory functions, but this is
a step in the right direction

Pick-to: 6.5
Change-Id: Id2f67597c8d8271b184321d138e126edff5f3202
Reviewed-by: Tim Blechmann <tim@klingt.org>
Reviewed-by: Artem Dyomin <artem.dyomin@qt.io>
Reviewed-by: Lars Sutterud <lars.sutterud@qt.io>
Reviewed-by: Jøger Hansegård <joger.hansegard@qt.io>
(cherry picked from commit 32f6952b03ba0e550db3e9dc358c366bf52c54a9)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
(cherry picked from commit 0d2f051469ccabc3a9dab7d5aae9658f33525aaf)

5 files changed, 21 insertions, 15 deletions

diff --git a/src/multimedia/audio/qsoundeffect.cpp b/src/multimedia/audio/qsoundeffect.cpp
index e5cb99144..4685b4671 100644
--- a/src/multimedia/audio/qsoundeffect.cpp
+++ b/src/multimedia/audio/qsoundeffect.cpp
@@ -127,14 +127,14 @@ void QSoundEffectPrivate::sampleReady()
                                     << audioDevice.channelConfiguration();
             auto outputFormat = sampleFormat;
             outputFormat.setChannelConfig(audioDevice.channelConfiguration());
-            if (auto maybeResampler = QPlatformMediaIntegration::instance()->createAudioResampler(
-                        m_sample->format(), outputFormat)) {
-                std::unique_ptr<QPlatformAudioResampler> resampler(maybeResampler.value());
-                m_audioBuffer =
-                        resampler->resample(m_sample->data().constData(), m_sample->data().size());
-            } else {
+
+            const auto resampler = QPlatformMediaIntegration::instance()->createAudioResampler(
+                    m_sample->format(), outputFormat);
+            if (resampler)
+                m_audioBuffer = resampler.value()->resample(m_sample->data().constData(),
+                                                            m_sample->data().size());
+            else
                 qCDebug(qLcSoundEffect) << "Cannot create resampler for channels mapping";
-            }
         }
 
         if (!m_audioBuffer.isValid())
diff --git a/src/multimedia/platform/qplatformmediaintegration.cpp b/src/multimedia/platform/qplatformmediaintegration.cpp
index dcb412acf..1eb113b28 100644
--- a/src/multimedia/platform/qplatformmediaintegration.cpp
+++ b/src/multimedia/platform/qplatformmediaintegration.cpp
@@ -7,6 +7,7 @@
 #include <qmutex.h>
 #include <qplatformaudioinput_p.h>
 #include <qplatformaudiooutput_p.h>
+#include <qplatformaudioresampler_p.h>
 #include <qplatformvideodevices_p.h>
 #include <qmediadevices.h>
 #include <qcameradevice.h>
@@ -118,6 +119,12 @@ QList<QCameraDevice> QPlatformMediaIntegration::videoInputs()
     return devices ? devices->videoDevices() : QList<QCameraDevice>{};
 }
 
+QMaybe<std::unique_ptr<QPlatformAudioResampler>>
+QPlatformMediaIntegration::createAudioResampler(const QAudioFormat &, const QAudioFormat &)
+{
+    return notAvailable;
+}
+
 QMaybe<QPlatformAudioInput *> QPlatformMediaIntegration::createAudioInput(QAudioInput *q)
 {
     return new QPlatformAudioInput(q);
diff --git a/src/multimedia/platform/qplatformmediaintegration_p.h b/src/multimedia/platform/qplatformmediaintegration_p.h
index 4673c47b3..d47687586 100644
--- a/src/multimedia/platform/qplatformmediaintegration_p.h
+++ b/src/multimedia/platform/qplatformmediaintegration_p.h
@@ -71,12 +71,9 @@ public:
     virtual QPlatformSurfaceCapture *createWindowCapture(QWindowCapture *) { return nullptr; }
 
     virtual QMaybe<QPlatformAudioDecoder *> createAudioDecoder(QAudioDecoder *) { return notAvailable; }
-    virtual QMaybe<QPlatformAudioResampler *>
+    virtual QMaybe<std::unique_ptr<QPlatformAudioResampler>>
     createAudioResampler(const QAudioFormat & /*inputFormat*/,
-                         const QAudioFormat & /*outputFormat*/)
-    {
-        return notAvailable;
-    }
+                         const QAudioFormat & /*outputFormat*/);
     virtual QMaybe<QPlatformMediaCaptureSession *> createCaptureSession() { return notAvailable; }
     virtual QMaybe<QPlatformMediaPlayer *> createPlayer(QMediaPlayer *) { return notAvailable; }
     virtual QMaybe<QPlatformMediaRecorder *> createRecorder(QMediaRecorder *) { return notAvailable; }
diff --git a/src/plugins/multimedia/ffmpeg/qffmpegmediaintegration.cpp b/src/plugins/multimedia/ffmpeg/qffmpegmediaintegration.cpp
index 7abded14c..28c0625c7 100644
--- a/src/plugins/multimedia/ffmpeg/qffmpegmediaintegration.cpp
+++ b/src/plugins/multimedia/ffmpeg/qffmpegmediaintegration.cpp
@@ -190,9 +190,11 @@ QMaybe<QPlatformAudioDecoder *> QFFmpegMediaIntegration::createAudioDecoder(QAud
     return new QFFmpegAudioDecoder(decoder);
 }
 
-QMaybe<QPlatformAudioResampler *> QFFmpegMediaIntegration::createAudioResampler(const QAudioFormat &inputFormat, const QAudioFormat &outputFormat)
+QMaybe<std::unique_ptr<QPlatformAudioResampler>>
+QFFmpegMediaIntegration::createAudioResampler(const QAudioFormat &inputFormat,
+                                              const QAudioFormat &outputFormat)
 {
-    return new QFFmpegResampler(inputFormat, outputFormat);
+    return { std::make_unique<QFFmpegResampler>(inputFormat, outputFormat) };
 }
 
 QMaybe<QPlatformMediaCaptureSession *> QFFmpegMediaIntegration::createCaptureSession()
diff --git a/src/plugins/multimedia/ffmpeg/qffmpegmediaintegration_p.h b/src/plugins/multimedia/ffmpeg/qffmpegmediaintegration_p.h
index 7d56b60bb..b8787bcc4 100644
--- a/src/plugins/multimedia/ffmpeg/qffmpegmediaintegration_p.h
+++ b/src/plugins/multimedia/ffmpeg/qffmpegmediaintegration_p.h
@@ -27,7 +27,7 @@ public:
     QFFmpegMediaIntegration();
 
     QMaybe<QPlatformAudioDecoder *> createAudioDecoder(QAudioDecoder *decoder) override;
-    QMaybe<QPlatformAudioResampler *> createAudioResampler(const QAudioFormat &inputFormat, const QAudioFormat &outputFormat) override;
+    QMaybe<std::unique_ptr<QPlatformAudioResampler>> createAudioResampler(const QAudioFormat &inputFormat, const QAudioFormat &outputFormat) override;
     QMaybe<QPlatformMediaCaptureSession *> createCaptureSession() override;
     QMaybe<QPlatformMediaPlayer *> createPlayer(QMediaPlayer *player) override;
     QMaybe<QPlatformCamera *> createCamera(QCamera *) override;