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/SourceFloat.cpp b/media/libaaudio/src/flowgraph/SourceFloat.cpp
new file mode 100644
index 0000000..4bb674f
--- /dev/null
+++ b/media/libaaudio/src/flowgraph/SourceFloat.cpp
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2018 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 <algorithm>
+#include <unistd.h>
+#include "AudioProcessorBase.h"
+#include "SourceFloat.h"
+
+using namespace flowgraph;
+
+SourceFloat::SourceFloat(int32_t channelCount)
+ : AudioSource(channelCount) {
+}
+
+int32_t SourceFloat::onProcess(int64_t framePosition, int32_t numFrames) {
+
+ float *outputBuffer = output.getBlock();
+ int32_t channelCount = output.getSamplesPerFrame();
+
+ int32_t framesLeft = mSizeInFrames - mFrameIndex;
+ int32_t framesToProcess = std::min(numFrames, framesLeft);
+ int32_t numSamples = framesToProcess * channelCount;
+
+ const float *floatBase = (float *) mData;
+ const float *floatData = &floatBase[mFrameIndex * channelCount];
+ memcpy(outputBuffer, floatData, numSamples * sizeof(float));
+ mFrameIndex += framesToProcess;
+ return framesToProcess;
+}
+