Import Android SDK Platform PI [4335822]

/google/data/ro/projects/android/fetch_artifact \
    --bid 4335822 \
    --target sdk_phone_armv7-win_sdk \
    sdk-repo-linux-sources-4335822.zip

AndroidVersion.ApiLevel has been modified to appear as 28

Change-Id: Ic8f04be005a71c2b9abeaac754d8da8d6f9a2c32

1 files changed, 150 insertions, 0 deletions

diff --git a/android/media/ResampleInputStream.java b/android/media/ResampleInputStream.java
new file mode 100644
index 00000000..80919f7f
--- /dev/null
+++ b/android/media/ResampleInputStream.java
@@ -0,0 +1,150 @@
+/*
+ * Copyright (C) 2008 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.
+ */
+
+package android.media;
+
+import java.io.InputStream;
+import java.io.IOException;
+
+
+/**
+ * ResampleInputStream
+ * @hide
+ */
+public final class ResampleInputStream extends InputStream
+{    
+    static {
+        System.loadLibrary("media_jni");
+    }
+    
+    private final static String TAG = "ResampleInputStream";
+    
+    // pcm input stream
+    private InputStream mInputStream;
+
+    // sample rates, assumed to be normalized
+    private final int mRateIn;
+    private final int mRateOut;
+    
+    // input pcm data
+    private byte[] mBuf;
+    private int mBufCount;
+    
+    // length of 2:1 fir
+    private static final int mFirLength = 29;
+    
+    // helper for bytewise read()
+    private final byte[] mOneByte = new byte[1];
+    
+    /**
+     * Create a new ResampleInputStream, which converts the sample rate
+     * @param inputStream InputStream containing 16 bit PCM.
+     * @param rateIn the input sample rate.
+     * @param rateOut the output sample rate.
+     * This only handles rateIn == rateOut / 2 for the moment.
+     */
+    public ResampleInputStream(InputStream inputStream, int rateIn, int rateOut) {
+        // only support 2:1 at the moment
+        if (rateIn != 2 * rateOut) throw new IllegalArgumentException("only support 2:1 at the moment");
+        rateIn = 2;
+        rateOut = 1;
+
+        mInputStream = inputStream;
+        mRateIn = rateIn;
+        mRateOut = rateOut;
+    }
+
+    @Override
+    public int read() throws IOException {
+        int rtn = read(mOneByte, 0, 1);
+        return rtn == 1 ? (0xff & mOneByte[0]) : -1;
+    }
+    
+    @Override
+    public int read(byte[] b) throws IOException {
+        return read(b, 0, b.length);
+    }
+
+    @Override
+    public int read(byte[] b, int offset, int length) throws IOException {
+        if (mInputStream == null) throw new IllegalStateException("not open");
+
+        // ensure that mBuf is big enough to cover requested 'length'
+        int nIn = ((length / 2) * mRateIn / mRateOut + mFirLength) * 2;
+        if (mBuf == null) {
+            mBuf = new byte[nIn];
+        } else if (nIn > mBuf.length) {
+            byte[] bf = new byte[nIn];
+            System.arraycopy(mBuf, 0, bf, 0, mBufCount);
+            mBuf = bf;
+        }
+        
+        // read until we have enough data for at least one output sample
+        while (true) {
+            int len = ((mBufCount / 2 - mFirLength) * mRateOut / mRateIn) * 2;
+            if (len > 0) {
+                length = len < length ? len : (length / 2) * 2;
+                break;
+            }
+            // TODO: should mBuf.length below be nIn instead?
+            int n = mInputStream.read(mBuf, mBufCount, mBuf.length - mBufCount);
+            if (n == -1) return -1;
+            mBufCount += n;
+        }
+
+        // resample input data
+        fir21(mBuf, 0, b, offset, length / 2);
+        
+        // move any unused bytes to front of mBuf
+        int nFwd = length * mRateIn / mRateOut;
+        mBufCount -= nFwd;
+        if (mBufCount > 0) System.arraycopy(mBuf, nFwd, mBuf, 0, mBufCount);
+        
+        return length;
+    }
+
+/*
+    @Override
+    public int available() throws IOException {
+        int nsamples = (mIn - mOut + mInputStream.available()) / 2;
+        return ((nsamples - mFirLength) * mRateOut / mRateIn) * 2;
+    }
+*/
+
+    @Override
+    public void close() throws IOException {
+        try {
+            if (mInputStream != null) mInputStream.close();
+        } finally {
+            mInputStream = null;
+        }
+    }
+
+    @Override
+    protected void finalize() throws Throwable {
+        if (mInputStream != null) {
+            close();
+            throw new IllegalStateException("someone forgot to close ResampleInputStream");
+        }
+    }
+
+    //
+    // fir filter code JNI interface
+    //
+    private static native void fir21(byte[] in, int inOffset,
+            byte[] out, int outOffset, int npoints);
+
+}