aaudio: add simple flowgraph system
Implement a simple data flow model that can be used to
chain various processing modules including:
data format conversion
volume ramping
channel conversion
Bug: 65067568
Test: test_flowgraph.cpp
Change-Id: I81a5655406cfa8c1c7d7cef4d933879f823939a5
diff --git a/media/libaaudio/src/flowgraph/MonoToMultiConverter.cpp b/media/libaaudio/src/flowgraph/MonoToMultiConverter.cpp
new file mode 100644
index 0000000..78aad52
--- /dev/null
+++ b/media/libaaudio/src/flowgraph/MonoToMultiConverter.cpp
@@ -0,0 +1,47 @@
+/*
+ * Copyright 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+#include <unistd.h>
+#include "AudioProcessorBase.h"
+#include "MonoToMultiConverter.h"
+
+using namespace flowgraph;
+
+MonoToMultiConverter::MonoToMultiConverter(int32_t channelCount)
+ : input(*this, 1)
+ , output(*this, channelCount) {
+}
+
+MonoToMultiConverter::~MonoToMultiConverter() { }
+
+int32_t MonoToMultiConverter::onProcess(int64_t framePosition, int32_t numFrames) {
+ int32_t framesToProcess = input.pullData(framePosition, numFrames);
+
+ const float *inputBuffer = input.getBlock();
+ float *outputBuffer = output.getBlock();
+ int32_t channelCount = output.getSamplesPerFrame();
+ // TODO maybe move to audio_util as audio_mono_to_multi()
+ for (int i = 0; i < framesToProcess; i++) {
+ // read one, write many
+ float sample = *inputBuffer++;
+ for (int channel = 0; channel < channelCount; channel++) {
+ *outputBuffer++ = sample;
+ }
+ }
+ return framesToProcess;
+}
+