Extract resampling of decoded frame into function

mixxxdj · Sep 8, 2019 · 5a85b9a · 5a85b9a
1 parent d8c78d7
commit 5a85b9a
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Showing 2 changed files with 45 additions and 37 deletions.
diff --git a/src/sources/soundsourceffmpeg.cpp b/src/sources/soundsourceffmpeg.cpp
@@ -946,6 +946,45 @@ bool SoundSourceFFmpeg::consumeNextPacket(
     return true;
 }
 
+const CSAMPLE* SoundSourceFFmpeg::resampleDecodedFrame() {
+    if (m_pSwrContext) {
+        // Decoded frame must be resampled before reading
+        m_pavResampledFrame->channel_layout = m_avResampledChannelLayout;
+        m_pavResampledFrame->sample_rate = sampleRate();
+        m_pavResampledFrame->format = kavSampleFormat;
+        if (m_pavDecodedFrame->channel_layout == kavChannelLayoutUndefined) {
+            // Sometimes the channel layout is undefined.
+            m_pavDecodedFrame->channel_layout = m_avStreamChannelLayout;
+        }
+#if ENABLE_TRACING
+        avTrace("Resampling decoded frame", *m_pavDecodedFrame);
+#endif
+        const auto swr_convert_frame_result =
+                swr_convert_frame(
+                        m_pSwrContext,
+                        m_pavResampledFrame,
+                        m_pavDecodedFrame);
+        if (swr_convert_frame_result != 0) {
+            kLogger.warning()
+                    << "swr_convert_frame() failed:"
+                    << formatErrorMessage(swr_convert_frame_result).toLocal8Bit().constData();
+            // Discard decoded frame and abort after unrecoverable error
+            av_frame_unref(m_pavDecodedFrame);
+            return nullptr;
+        }
+#if ENABLE_TRACING
+        avTrace("Received resampled frame", *m_pavResampledFrame);
+#endif
+        DEBUG_ASSERT(m_pavDecodedFrame->pts = m_pavResampledFrame->pts);
+        DEBUG_ASSERT(m_pavDecodedFrame->nb_samples = m_pavResampledFrame->nb_samples);
+        return reinterpret_cast<const CSAMPLE*>(
+                m_pavResampledFrame->extended_data[0]);
+    } else {
+        return reinterpret_cast<const CSAMPLE*>(
+                m_pavDecodedFrame->extended_data[0]);
+    }
+}
+
 ReadableSampleFrames SoundSourceFFmpeg::readSampleFramesClamped(
         WritableSampleFrames writableSampleFrames) {
     const SINT readableStartIndex = writableSampleFrames.frameIndexRange().start();
@@ -1000,7 +1039,6 @@ ReadableSampleFrames SoundSourceFFmpeg::readSampleFramesClamped(
             DEBUG_ASSERT(writableRange.empty() || m_sampleBuffer.empty());
 
             SINT missingFrameCount = 0;
-            const CSAMPLE* pDecodedSampleData = nullptr;
 
             // Decode next frame
             IndexRange decodedFrameRange;
@@ -1148,42 +1186,11 @@ ReadableSampleFrames SoundSourceFFmpeg::readSampleFramesClamped(
             // This is expected behavior and will be compensated during 'preskip'
             // (see below).
 
-            if (m_pSwrContext) {
-                // Decoded frame must be resampled before reading
-                m_pavResampledFrame->channel_layout = m_avResampledChannelLayout;
-                m_pavResampledFrame->sample_rate = sampleRate();
-                m_pavResampledFrame->format = kavSampleFormat;
-                if (m_pavDecodedFrame->channel_layout == kavChannelLayoutUndefined) {
-                    // Sometimes the channel layout is undefined.
-                    m_pavDecodedFrame->channel_layout = m_avStreamChannelLayout;
-                }
-#if ENABLE_TRACING
-                avTrace("Resampling decoded frame", *m_pavDecodedFrame);
-#endif
-                const auto swr_convert_frame_result =
-                        swr_convert_frame(
-                                m_pSwrContext,
-                                m_pavResampledFrame,
-                                m_pavDecodedFrame);
-                if (swr_convert_frame_result != 0) {
-                    kLogger.warning()
-                            << "swr_convert_frame() failed:"
-                            << formatErrorMessage(swr_convert_frame_result).toLocal8Bit().constData();
-                    // Abort reading
-                    av_frame_unref(m_pavDecodedFrame);
-                    m_curFrameIndex = kFrameIndexInvalid;
-                    break;
-                }
-#if ENABLE_TRACING
-                avTrace("Received resampled frame", *m_pavResampledFrame);
-#endif
-                DEBUG_ASSERT(m_pavDecodedFrame->pts = m_pavResampledFrame->pts);
-                DEBUG_ASSERT(m_pavDecodedFrame->nb_samples = m_pavResampledFrame->nb_samples);
-                pDecodedSampleData = reinterpret_cast<const CSAMPLE*>(
-                        m_pavResampledFrame->extended_data[0]);
-            } else {
-                pDecodedSampleData = reinterpret_cast<const CSAMPLE*>(
-                        m_pavDecodedFrame->extended_data[0]);
+            const CSAMPLE* pDecodedSampleData = resampleDecodedFrame();
+            if (!pDecodedSampleData) {
+                // Invalidate current position and abort reading after unrecoverable error
+                m_curFrameIndex = kFrameIndexInvalid;
+                break;
             }
 
             // readFrameIndex

diff --git a/src/sources/soundsourceffmpeg.h b/src/sources/soundsourceffmpeg.h
@@ -33,6 +33,7 @@ class SoundSourceFFmpeg : public SoundSource {
     bool initResampling(
             ChannelCount* pResampledChannelCount,
             SampleRate* pResampledSampleRate);
+    const CSAMPLE* resampleDecodedFrame();
 
     // Consume as many buffered sample frames as possible and return
     // the remaining range that could not be filled from the  buffer.