android_media_AmrInputStream.cpp revision 3ca47d101db63b619f15723d5131ff7bc8f3a5be 
1/*
2**
3** Copyright 2007, The Android Open Source Project
4**
5** Licensed under the Apache License, Version 2.0 (the "License");
6** you may not use this file except in compliance with the License.
7** You may obtain a copy of the License at
8**
9**     http://www.apache.org/licenses/LICENSE-2.0
10**
11** Unless required by applicable law or agreed to in writing, software
12** distributed under the License is distributed on an "AS IS" BASIS,
13** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14** See the License for the specific language governing permissions and
15** limitations under the License.
16*/
17
18#define LOG_TAG "AmrInputStream"
19#include "utils/Log.h"
20
21#include <media/mediarecorder.h>
22#include <stdio.h>
23#include <assert.h>
24#include <limits.h>
25#include <unistd.h>
26#include <fcntl.h>
27#include <utils/threads.h>
28
29#include "jni.h"
30#include "JNIHelp.h"
31#include "android_runtime/AndroidRuntime.h"
32#include "gsmamr_encoder_wrapper.h"
33
34
35// ----------------------------------------------------------------------------
36
37using namespace android;
38
39// Corresponds to max bit rate of 12.2 kbps.
40static const int aMaxOutputBufferSize = 32;
41
42static const int SAMPLES_PER_FRAME = 8000 * 20 / 1000;
43
44
45//
46// helper function to throw an exception
47//
48static void throwException(JNIEnv *env, const char* ex, const char* fmt, int data) {
49    if (jclass cls = env->FindClass(ex)) {
50        char msg[1000];
51        sprintf(msg, fmt, data);
52        env->ThrowNew(cls, msg);
53        env->DeleteLocalRef(cls);
54    }
55}
56
57static jint android_media_AmrInputStream_GsmAmrEncoderNew
58        (JNIEnv *env, jclass clazz) {
59    CPvGsmAmrEncoder* gae = new CPvGsmAmrEncoder();
60    if (gae == NULL) {
61        throwException(env, "java/lang/IllegalStateException",
62                "new CPvGsmAmrEncoder() failed", 0);
63    }
64    return (jint)gae;
65}
66
67static void android_media_AmrInputStream_GsmAmrEncoderInitialize
68        (JNIEnv *env, jclass clazz, jint gae) {
69    // set input parameters
70    TEncodeProperties encodeProps;
71    encodeProps.iInBitsPerSample = 16;
72    encodeProps.iInSamplingRate = 8000;
73    encodeProps.iInClockRate = 1000;
74    encodeProps.iInNumChannels = 1;
75    encodeProps.iInInterleaveMode = TEncodeProperties::EINTERLEAVE_LR;
76    encodeProps.iMode = CPvGsmAmrEncoder::GSM_AMR_12_2;
77    encodeProps.iBitStreamFormat = false;
78    encodeProps.iAudioObjectType = 0;
79    encodeProps.iOutSamplingRate = encodeProps.iInSamplingRate;
80    encodeProps.iOutNumChannels = encodeProps.iInNumChannels;
81    encodeProps.iOutClockRate = encodeProps.iInClockRate;
82
83    if (int rtn = ((CPvGsmAmrEncoder*)gae)->
84            InitializeEncoder(aMaxOutputBufferSize, &encodeProps)) {
85        throwException(env, "java/lang/IllegalArgumentException",
86                "CPvGsmAmrEncoder::InitializeEncoder failed %d", rtn);
87    }
88}
89
90static jint android_media_AmrInputStream_GsmAmrEncoderEncode
91        (JNIEnv *env, jclass clazz,
92         jint gae, jbyteArray pcm, jint pcmOffset, jbyteArray amr, jint amrOffset) {
93
94    // set up input stream
95    jbyte inBuf[SAMPLES_PER_FRAME*2];
96    TInputAudioStream in;
97    in.iSampleBuffer = (uint8*)inBuf;
98    env->GetByteArrayRegion(pcm, pcmOffset, sizeof(inBuf), inBuf);
99    in.iSampleLength = sizeof(inBuf);
100    in.iMode = CPvGsmAmrEncoder::GSM_AMR_12_2;
101    in.iStartTime = 0;
102    in.iStopTime = 0;
103
104    // set up output stream
105    jbyte outBuf[aMaxOutputBufferSize];
106    int32 sampleFrameSize[1] = { 0 };
107    TOutputAudioStream out;
108    out.iBitStreamBuffer = (uint8*)outBuf;
109    out.iNumSampleFrames = 0;
110    out.iSampleFrameSize = sampleFrameSize;
111    out.iStartTime = 0;
112    out.iStopTime = 0;
113
114    // encode
115    if (int rtn = ((CPvGsmAmrEncoder*)gae)->Encode(in, out)) {
116        throwException(env, "java/io/IOException", "CPvGsmAmrEncoder::Encode failed %d", rtn);
117        return -1;
118    }
119
120    // validate one-frame assumption
121    if (out.iNumSampleFrames != 1) {
122        throwException(env, "java/io/IOException",
123                "CPvGsmAmrEncoder::Encode more than one frame returned %d", out.iNumSampleFrames);
124        return 0;
125    }
126
127    // copy result
128    int length = out.iSampleFrameSize[0];
129
130    // The 1st byte of PV AMR frames are WMF (Wireless Multimedia Forum)
131    // bitpacked, i.e.;
132    //    [P(4) + FT(4)]. Q=1 for good frame, P=padding bit, 0
133    // Here we are converting the header to be as specified in Section 5.3 of
134    // RFC 3267 (AMR storage format) i.e.
135    //    [P(1) + FT(4) + Q(1) + P(2)].
136    if (length > 0) {
137      outBuf[0] = (outBuf[0] << 3) | 0x4;
138    }
139
140    env->SetByteArrayRegion(amr, amrOffset, length, outBuf);
141
142    return length;
143}
144
145static void android_media_AmrInputStream_GsmAmrEncoderCleanup
146        (JNIEnv *env, jclass clazz, jint gae) {
147    if (int rtn = ((CPvGsmAmrEncoder*)gae)->CleanupEncoder()) {
148        throwException(env, "java/lang/IllegalStateException",
149                "CPvGsmAmrEncoder::CleanupEncoder failed %d", rtn);
150    }
151}
152
153static void android_media_AmrInputStream_GsmAmrEncoderDelete
154        (JNIEnv *env, jclass clazz, jint gae) {
155    delete (CPvGsmAmrEncoder*)gae;
156}
157
158// ----------------------------------------------------------------------------
159
160static JNINativeMethod gMethods[] = {
161    {"GsmAmrEncoderNew",        "()I",        (void*)android_media_AmrInputStream_GsmAmrEncoderNew},
162    {"GsmAmrEncoderInitialize", "(I)V",       (void*)android_media_AmrInputStream_GsmAmrEncoderInitialize},
163    {"GsmAmrEncoderEncode",     "(I[BI[BI)I", (void*)android_media_AmrInputStream_GsmAmrEncoderEncode},
164    {"GsmAmrEncoderCleanup",    "(I)V",       (void*)android_media_AmrInputStream_GsmAmrEncoderCleanup},
165    {"GsmAmrEncoderDelete",     "(I)V",       (void*)android_media_AmrInputStream_GsmAmrEncoderDelete},
166};
167
168
169int register_android_media_AmrInputStream(JNIEnv *env)
170{
171    const char* const kClassPathName = "android/media/AmrInputStream";
172    jclass clazz;
173
174    clazz = env->FindClass(kClassPathName);
175    if (clazz == NULL) {
176        LOGE("Can't find %s", kClassPathName);
177        return -1;
178    }
179
180    return AndroidRuntime::registerNativeMethods(env,
181            kClassPathName, gMethods, NELEM(gMethods));
182}
183
184
185