| /* |
| ** |
| ** Copyright 2007, 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. |
| */ |
| |
| #define LOG_TAG "ResampleInputStream" |
| #include "utils/Log.h" |
| |
| #include <media/mediarecorder.h> |
| #include <stdio.h> |
| #include <assert.h> |
| #include <limits.h> |
| #include <unistd.h> |
| #include <fcntl.h> |
| #include <utils/threads.h> |
| |
| #include "jni.h" |
| #include "JNIHelp.h" |
| #include "android_runtime/AndroidRuntime.h" |
| |
| |
| // ---------------------------------------------------------------------------- |
| |
| using namespace android; |
| |
| |
| #define FIR_COEF(coef) (short)(0x10000 * coef) |
| static const short fir21[] = { |
| FIR_COEF(-0.006965742326), |
| FIR_COEF(-0.008428945737), |
| FIR_COEF( 0.004241280174), |
| FIR_COEF( 0.022141096893), |
| FIR_COEF( 0.018765669437), |
| FIR_COEF(-0.009871891152), |
| FIR_COEF(-0.024842433247), |
| FIR_COEF( 0.006121772058), |
| FIR_COEF( 0.045890841611), |
| FIR_COEF( 0.021573503509), |
| FIR_COEF(-0.059681984668), |
| FIR_COEF(-0.076036275138), |
| FIR_COEF( 0.072405390275), |
| FIR_COEF( 0.308255674582), |
| FIR_COEF( 0.424321210495), |
| FIR_COEF( 0.308255674582), |
| FIR_COEF( 0.072405390275), |
| FIR_COEF(-0.076036275138), |
| FIR_COEF(-0.059681984668), |
| FIR_COEF( 0.021573503509), |
| FIR_COEF( 0.045890841611), |
| FIR_COEF( 0.006121772058), |
| FIR_COEF(-0.024842433247), |
| FIR_COEF(-0.009871891152), |
| FIR_COEF( 0.018765669437), |
| FIR_COEF( 0.022141096893), |
| FIR_COEF( 0.004241280174), |
| FIR_COEF(-0.008428945737), |
| FIR_COEF(-0.006965742326) |
| }; |
| static const int nFir21 = sizeof(fir21) / sizeof(fir21[0]); |
| |
| static const int BUF_SIZE = 2048; |
| |
| |
| static void android_media_ResampleInputStream_fir21(JNIEnv *env, jclass /* clazz */, |
| jbyteArray jIn, jint jInOffset, |
| jbyteArray jOut, jint jOutOffset, |
| jint jNpoints) { |
| |
| // safety first! |
| if (nFir21 + jNpoints * 2 > BUF_SIZE) { |
| jniThrowExceptionFmt(env, "java/lang/IllegalArgumentException", |
| "FIR+data too long %d", nFir21 + jNpoints); |
| return; |
| } |
| |
| // get input data |
| short in[BUF_SIZE]; |
| env->GetByteArrayRegion(jIn, jInOffset, (jNpoints * 2 + nFir21 - 1) * 2, (jbyte*)in); |
| |
| // compute filter |
| short out[BUF_SIZE]; |
| for (int i = 0; i < jNpoints; i++) { |
| long sum = 0; |
| const short* firp = &fir21[0]; |
| const short* inp = &in[i * 2]; |
| for (int n = nFir21; --n >= 0; ) { |
| sum += ((long)*firp++) * ((long)*inp++); |
| } |
| out[i] = (short)(sum >> 16); |
| } |
| |
| // save new values |
| env->SetByteArrayRegion(jOut, jOutOffset, jNpoints * 2, (jbyte*)out); |
| } |
| |
| // ---------------------------------------------------------------------------- |
| |
| static JNINativeMethod gMethods[] = { |
| {"fir21", "([BI[BII)V", (void*)android_media_ResampleInputStream_fir21}, |
| }; |
| |
| |
| int register_android_media_ResampleInputStream(JNIEnv *env) |
| { |
| const char* const kClassPathName = "android/media/ResampleInputStream"; |
| |
| return AndroidRuntime::registerNativeMethods(env, |
| kClassPathName, gMethods, NELEM(gMethods)); |
| } |