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/SinkI24.cpp b/media/libaaudio/src/flowgraph/SinkI24.cpp
new file mode 100644
index 0000000..6592828
--- /dev/null
+++ b/media/libaaudio/src/flowgraph/SinkI24.cpp
@@ -0,0 +1,66 @@
+/*
+ * 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>
+
+#ifdef __ANDROID__
+#include <audio_utils/primitives.h>
+#endif
+
+#include "AudioProcessorBase.h"
+#include "SinkI24.h"
+
+using namespace flowgraph;
+
+
+SinkI24::SinkI24(int32_t channelCount)
+ : AudioSink(channelCount) {}
+
+int32_t SinkI24::read(void *data, int32_t numFrames) {
+ uint8_t *byteData = (uint8_t *) data;
+ const int32_t channelCount = input.getSamplesPerFrame();
+
+ int32_t framesLeft = numFrames;
+ while (framesLeft > 0) {
+ // Run the graph and pull data through the input port.
+ int32_t framesRead = pull(framesLeft);
+ if (framesRead <= 0) {
+ break;
+ }
+ const float *floatData = input.getBlock();
+ int32_t numSamples = framesRead * channelCount;
+#ifdef __ANDROID__
+ memcpy_to_p24_from_float(byteData, floatData, numSamples);
+ static const int kBytesPerI24Packed = 3;
+ byteData += numSamples * kBytesPerI24Packed;
+ floatData += numSamples;
+#else
+ const int32_t kI24PackedMax = 0x007FFFFF;
+ const int32_t kI24PackedMin = 0xFF800000;
+ for (int i = 0; i < numSamples; i++) {
+ int32_t n = (int32_t) (*floatData++ * 0x00800000);
+ n = std::min(kI24PackedMax, std::max(kI24PackedMin, n)); // clip
+ // Write as a packed 24-bit integer in Little Endian format.
+ *byteData++ = (uint8_t) n;
+ *byteData++ = (uint8_t) (n >> 8);
+ *byteData++ = (uint8_t) (n >> 16);
+ }
+#endif
+ framesLeft -= framesRead;
+ }
+ return numFrames - framesLeft;
+}