use ffmpeg for sample packing

FFmpeg has a much more optimized algorithm than we do so may as well use it.

app/audio/CMakeLists.txt

@@ -16,15 +16,17 @@
 
 set(OLIVE_SOURCES
   ${OLIVE_SOURCES}
-  audio/audiomanager.h
   audio/audiomanager.cpp
-  audio/audiovisualwaveform.h
+  audio/audiomanager.h
   audio/audiovisualwaveform.cpp
-  audio/outputdeviceproxy.h
+  audio/audiovisualwaveform.h
   audio/outputdeviceproxy.cpp
-  audio/outputmanager.h
+  audio/outputdeviceproxy.h
   audio/outputmanager.cpp
-  audio/tempoprocessor.h
+  audio/outputmanager.h
+  audio/packedprocessor.cpp
+  audio/packedprocessor.h
   audio/tempoprocessor.cpp
+  audio/tempoprocessor.h
   PARENT_SCOPE
 )

app/audio/packedprocessor.cpp

@@ -0,0 +1,106 @@
+/***
+
+  Olive - Non-Linear Video Editor
+  Copyright (C) 2021 Olive Team
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+***/
+
+#include "packedprocessor.h"
+
+#include "common/ffmpegutils.h"
+
+namespace olive {
+
+PackedProcessor::PackedProcessor() :
+  swr_ctx_(nullptr)
+{
+}
+
+PackedProcessor::~PackedProcessor()
+{
+  Close();
+}
+
+bool PackedProcessor::Open(const AudioParams &params)
+{
+  if (IsOpen()) {
+    return true;
+  }
+
+  swr_ctx_ = swr_alloc_set_opts(nullptr,
+                                params.channel_layout(),
+                                FFmpegUtils::GetFFmpegSampleFormat(params.format(), false),
+                                params.sample_rate(),
+                                params.channel_layout(),
+                                FFmpegUtils::GetFFmpegSampleFormat(params.format(), true),
+                                params.sample_rate(),
+                                0,
+                                nullptr);
+
+  if (!swr_ctx_) {
+    qCritical() << "Failed to allocate resample context";
+    return false;
+  }
+
+  if (swr_init(swr_ctx_) < 0) {
+    qCritical() << "Failed to init resample context";
+    swr_free(&swr_ctx_);
+    return false;
+  }
+
+  return true;
+}
+
+QByteArray PackedProcessor::Convert(SampleBufferPtr planar)
+{
+  if (!IsOpen()) {
+    qCritical() << "Tried to convert while closed";
+    return QByteArray();
+  }
+
+  int nb_samples = planar->sample_count();
+  if (nb_samples == 0) {
+    return QByteArray();
+  }
+
+  int nb_channels = planar->audio_params().channel_count();
+
+  QByteArray output(planar->audio_params().samples_to_bytes(nb_samples), Qt::Uninitialized);
+  uint8_t *output_data = reinterpret_cast<uint8_t*>(output.data());
+
+  QVector<const uint8_t*> input_arrays(nb_channels);
+  for (int i=0; i<nb_channels; i++) {
+    input_arrays[i] = reinterpret_cast<const uint8_t*>(planar->data(i));
+  }
+
+  int ret = swr_convert(swr_ctx_, &output_data, nb_samples, input_arrays.data(), nb_samples);
+  if (ret < 0) {
+    char buf[200];
+    av_strerror(ret, buf, 200);
+    qDebug() << "Packed processor failed with error:" << buf << ret;
+  }
+
+  return output;
+}
+
+void PackedProcessor::Close()
+{
+  if (swr_ctx_) {
+    swr_free(&swr_ctx_);
+  }
+}
+
+}

app/audio/packedprocessor.h

@@ -0,0 +1,60 @@
+/***
+
+  Olive - Non-Linear Video Editor
+  Copyright (C) 2021 Olive Team
+
+  This program is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+***/
+
+#ifndef PACKEDPROCESSOR_H
+#define PACKEDPROCESSOR_H
+
+extern "C" {
+#include <libswresample/swresample.h>
+}
+
+#include "codec/samplebuffer.h"
+#include "render/audioparams.h"
+
+namespace olive {
+
+class PackedProcessor
+{
+public:
+  PackedProcessor();
+
+  ~PackedProcessor();
+
+  DISABLE_COPY_MOVE(PackedProcessor)
+
+  bool Open(const AudioParams &params);
+
+  QByteArray Convert(SampleBufferPtr planar);
+
+  void Close();
+
+  bool IsOpen() const
+  {
+    return swr_ctx_;
+  }
+
+private:
+  SwrContext *swr_ctx_;
+
+};
+
+}
+
+#endif // PACKEDPROCESSOR_H

app/audio/tempoprocessor.cpp

@@ -39,7 +39,11 @@ TempoProcessor::TempoProcessor() :
   processed_frame_(nullptr),
   open_(false)
 {
+}
 
+TempoProcessor::~TempoProcessor()
+{
+  Close();
 }
 
 bool TempoProcessor::IsOpen() const

app/audio/tempoprocessor.h

@@ -42,6 +42,10 @@ class TempoProcessor
 public:
   TempoProcessor();
 
+  ~TempoProcessor();
+
+  DISABLE_COPY_MOVE(TempoProcessor)
+
   bool IsOpen() const;
 
   const double& GetSpeed() const;