ao: select a best sample sample format in setAudioFormat()

less computation in resampler if packed format of requested format is supported, e.g. fltp=>flt
lowTechnology · Jul 27, 2016 · b61894f · b61894f
1 parent ef2130b
commit b61894f
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Showing 3 changed files with 40 additions and 5 deletions.
diff --git a/src/AudioFormat.cpp b/src/AudioFormat.cpp
@@ -147,6 +147,18 @@ AudioFormat::SampleFormat AudioFormat::packedSampleFormat(SampleFormat fmt)
     return fmt;
 }
 
+AudioFormat::SampleFormat AudioFormat::make(int bytesPerSample, bool isFloat, bool isUnsigned, bool isPlanar)
+{
+    int f = bytesPerSample;
+    if (isFloat)
+        f |= kFloat;
+    if (isUnsigned)
+        f |= kUnsigned;
+    if (isPlanar)
+        f |= kPlanar;
+    return SampleFormat(f);
+}
+
 AudioFormat::SampleFormat AudioFormat::planarSampleFormat(SampleFormat fmt)
 {
     if (isPlanar(fmt))

diff --git a/src/QtAV/AudioFormat.h b/src/QtAV/AudioFormat.h
@@ -77,7 +77,7 @@ class Q_AV_EXPORT AudioFormat
     static bool isPlanar(SampleFormat format);
     static SampleFormat planarSampleFormat(SampleFormat fmt);
     static SampleFormat packedSampleFormat(SampleFormat fmt);
-
+    static SampleFormat make(int bytesPerSample, bool isFloat, bool isUnsigned, bool isPlanar);
     AudioFormat();
     AudioFormat(const AudioFormat &other);
     ~AudioFormat();

diff --git a/src/output/audio/AudioOutput.cpp b/src/output/audio/AudioOutput.cpp
@@ -356,6 +356,7 @@ bool AudioOutput::open()
     QMutexLocker lock(&d.mutex);
     Q_UNUSED(lock);
     d.available = false;
+    d.paused = false;
     d.resetStatus();
     if (!d.backend)
         return false;
@@ -379,6 +380,7 @@ bool AudioOutput::close()
     QMutexLocker lock(&d.mutex);
     Q_UNUSED(lock);
     d.available = false;
+    d.paused = false;
     d.resetStatus();
     if (!d.backend)
         return false;
@@ -417,7 +419,7 @@ bool AudioOutput::isPaused() const
 bool AudioOutput::receiveData(const QByteArray &data, qreal pts)
 {
     DPTR_D(AudioOutput);
-    if (d.paused)
+    if (isPaused())
         return false;
     d.data = data;
     if (isMute() && d.sw_mute) {
@@ -458,11 +460,32 @@ AudioFormat AudioOutput::setAudioFormat(const AudioFormat& format)
     AudioFormat af(format);
     if (d.backend) {
         if (!d.backend->isSupported(format)) {
-            if (!d.backend->isSupported(format.sampleFormat())) {
-                af.setSampleFormat(d.backend->preferredSampleFormat());
+            int ss = af.bytesPerSample();
+            while (!d.backend->isSupported(af.sampleFormat())) {
+                if (af.bytesPerSample() < 1) {
+                    if (ss > 1) {
+                        qWarning("No sample format found");
+                        break;
+                    }
+                    af.setSampleFormat(AudioFormat::SampleFormat_Float);
+                    ss = af.bytesPerSample();
+                    continue;
+                }
+                if (af.isPlanar()) {
+                    af.setSampleFormat(AudioFormat::packedSampleFormat(af.sampleFormat()));
+                    continue;
+                }
+                if (af.isFloat()) {
+                    if (af.bytesPerSample() == 8)
+                        af.setSampleFormat(AudioFormat::SampleFormat_Float);
+                    else
+                        af.setSampleFormat(AudioFormat::SampleFormat_Signed32);
+                } else {
+                    af.setSampleFormat(AudioFormat::make(af.bytesPerSample()/2, false, af.bytesPerSample() == 2 | af.isUnsigned() /* U8, no S8 */, false));
+                }
             }
             if (!d.backend->isSupported(format.channelLayout())) {
-                af.setChannelLayout(d.backend->preferredChannelLayout());
+                af.setChannelLayout(AudioFormat::ChannelLayout_Stereo); // assume stereo is supported
             }
         }
     }