技术标签: opensl ndk android audio ffmpeg 音频
类似文章太多,但是大多代码都有内存溢出的问题,而且都缺少c层调用java层的例子,实际上有了参考博文后,还是有很多坑需要自己填。不过,看了很多博主和帖子后还是能够解决一些问题,但是有些问题,根本找不到,所以我把音频解码播放还有控制部分做了比较详细的例子。
ffmpeg的编译请参考我之前的文章,有编好的库文件在我的下载资源里,github的demo里也有。
opensl库的引用也很简单,cmak里加入opensl就可以了,像这样
target_link_libraries( native-lib
android
ffmpeg
OpenSLES
${
log-lib} )
opensl使用步骤大概分三步
//创建OpenSLES引擎
extern "C"
void createEngine() {
SLresult result;
//创建引擎
result = slCreateEngine(&engineObject, 0, NULL, 0, NULL, NULL);
assert(SL_RESULT_SUCCESS == result);
(void) result;
//关联引擎
result = (*engineObject)->Realize(engineObject, SL_BOOLEAN_FALSE);
assert(SL_RESULT_SUCCESS == result);
(void) result;
//获取引擎接口, which is needed in order to create other objects
result = (*engineObject)->GetInterface(engineObject, SL_IID_ENGINE, &engineEngine);
assert(SL_RESULT_SUCCESS == result);
(void) result;
//创建输出混音器, with environmental reverb specified as a non-required interface
const SLInterfaceID ids[1] = {SL_IID_ENVIRONMENTALREVERB};
const SLboolean req[1] = {SL_BOOLEAN_FALSE};
result = (*engineEngine)->CreateOutputMix(engineEngine, &outputMixObject, 1, ids, req);
assert(SL_RESULT_SUCCESS == result);
(void) result;
//关联输出混音器
result = (*outputMixObject)->Realize(outputMixObject, SL_BOOLEAN_FALSE);
assert(SL_RESULT_SUCCESS == result);
(void) result;
// get the environmental reverb interface
// this could fail if the environmental reverb effect is not available,
// either because the feature is not present, excessive CPU load, or
// the required MODIFY_AUDIO_SETTINGS permission was not requested and granted
//获取reverb接口
result = (*outputMixObject)->GetInterface(outputMixObject, SL_IID_ENVIRONMENTALREVERB,
&outputMixEnvironmentalReverb);
if (SL_RESULT_SUCCESS == result) {
result = (*outputMixEnvironmentalReverb)->SetEnvironmentalReverbProperties(
outputMixEnvironmentalReverb, &reverbSettings);
(void) result;
}
// ignore unsuccessful result codes for environmental reverb, as it is optional for this example
}
// create buffer queue audio player
extern "C"
void createBufferQueueAudioPlayer(int sampleRate, int channel) {
SLresult result;
if (sampleRate >= 0) {
bqPlayerSampleRate = sampleRate * 1000;
}
//配置音频源
SLDataLocator_AndroidSimpleBufferQueue loc_bufq = {SL_DATALOCATOR_ANDROIDSIMPLEBUFFERQUEUE, 2};
SLDataFormat_PCM format_pcm = {SL_DATAFORMAT_PCM, 1, SL_SAMPLINGRATE_8,
SL_PCMSAMPLEFORMAT_FIXED_16, SL_PCMSAMPLEFORMAT_FIXED_16,
SL_SPEAKER_FRONT_CENTER, SL_BYTEORDER_LITTLEENDIAN};
if (bqPlayerSampleRate) {
format_pcm.samplesPerSec = bqPlayerSampleRate; //sample rate in mili second
}
format_pcm.numChannels = (SLuint32) channel;
if (channel == 2) {
format_pcm.channelMask = SL_SPEAKER_FRONT_LEFT | SL_SPEAKER_FRONT_RIGHT;
} else {
format_pcm.channelMask = SL_SPEAKER_FRONT_CENTER;
}
SLDataSource audioSrc = {&loc_bufq, &format_pcm};
//配置音频池
SLDataLocator_OutputMix loc_outmix = {SL_DATALOCATOR_OUTPUTMIX, outputMixObject};
SLDataSink audioSnk = {&loc_outmix, NULL};
/*
* create audio player:
* fast audio does not support when SL_IID_EFFECTSEND is required, skip it
* for fast audio case
*/
const SLInterfaceID ids[3] = {SL_IID_BUFFERQUEUE, SL_IID_VOLUME, SL_IID_EFFECTSEND,
/*SL_IID_MUTESOLO,*/};
const SLboolean req[3] = {SL_BOOLEAN_TRUE, SL_BOOLEAN_TRUE, SL_BOOLEAN_TRUE,
/*SL_BOOLEAN_TRUE,*/ };
//创建音频播放器
result = (*engineEngine)->CreateAudioPlayer(engineEngine, &bqPlayerObject, &audioSrc, &audioSnk,
bqPlayerSampleRate ? 2 : 3, ids, req);
assert(SL_RESULT_SUCCESS == result);
(void) result;
// 关联播放器
result = (*bqPlayerObject)->Realize(bqPlayerObject, SL_BOOLEAN_FALSE);
assert(SL_RESULT_SUCCESS == result);
(void) result;
// 获取播放接口
result = (*bqPlayerObject)->GetInterface(bqPlayerObject, SL_IID_PLAY, &bqPlayerPlay);
assert(SL_RESULT_SUCCESS == result);
(void) result;
// 获取缓冲队列接口
result = (*bqPlayerObject)->GetInterface(bqPlayerObject, SL_IID_BUFFERQUEUE,
&bqPlayerBufferQueue);
assert(SL_RESULT_SUCCESS == result);
(void) result;
// 注册缓冲队列回调
result = (*bqPlayerBufferQueue)->RegisterCallback(bqPlayerBufferQueue, bqPlayerCallback, NULL);
assert(SL_RESULT_SUCCESS == result);
(void) result;
// 获取音效接口
bqPlayerEffectSend = NULL;
if (0 == bqPlayerSampleRate) {
result = (*bqPlayerObject)->GetInterface(bqPlayerObject, SL_IID_EFFECTSEND,
&bqPlayerEffectSend);
assert(SL_RESULT_SUCCESS == result);
(void) result;
}
#if 0 // mute/solo is not supported for sources that are known to be mono, as this is
// get the mute/solo interface
result = (*bqPlayerObject)->GetInterface(bqPlayerObject, SL_IID_MUTESOLO, &bqPlayerMuteSolo);
assert(SL_RESULT_SUCCESS == result);
(void)result;
#endif
// 获取音量接口
result = (*bqPlayerObject)->GetInterface(bqPlayerObject, SL_IID_VOLUME, &bqPlayerVolume);
assert(SL_RESULT_SUCCESS == result);
(void) result;
//注册事件回调
result = (*bqPlayerPlay)->RegisterCallback(bqPlayerPlay, playOverEvent, NULL);
assert(SL_RESULT_SUCCESS == result);
(void) result;
//设置播放结束回调
result = (*bqPlayerPlay)->SetCallbackEventsMask(bqPlayerPlay, SL_PLAYEVENT_HEADATEND);
assert(SL_RESULT_SUCCESS == result);
(void) result;
// 开始播放音乐
result = (*bqPlayerPlay)->SetPlayState(bqPlayerPlay, SL_PLAYSTATE_PAUSED);
assert(SL_RESULT_SUCCESS == result);
(void) result;
}
void releaseResampleBuf(void) {
if (0 == bqPlayerSampleRate) {
/*
* we are not using fast path, so we were not creating buffers, nothing to do
*/
return;
}
free(resampleBuf);
resampleBuf = NULL;
}
// this callback handler is called every time a buffer finishes playing
extern "C"
void bqPlayerCallback(SLAndroidSimpleBufferQueueItf bq, void *context) {
assert(bq == bqPlayerBufferQueue);
assert(NULL == context);
// for streaming playback, replace this test by logic to find and fill the next buffer
if (getPCM() < 0) {
//解码音频文件
pthread_mutex_unlock(&audioEngineLock);
return;
}
if (NULL != nextBuffer && 0 != nextSize) {
SLresult result;
// enqueue another buffer
result = (*bqPlayerBufferQueue)->Enqueue(bqPlayerBufferQueue, nextBuffer, nextSize);
// the most likely other result is SL_RESULT_BUFFER_INSUFFICIENT,
// which for this code example would indicate a programming error
if (SL_RESULT_SUCCESS != result) {
pthread_mutex_unlock(&audioEngineLock);
}
(void) result;
} else {
releaseResampleBuf();
pthread_mutex_unlock(&audioEngineLock);
}
}
基本就这三步,在我理解里,其实opensl就是一个播放器的api,我们这里也就是简单调用封装好的方法而已。
播放音频当然还需要数据,opensl本身可以读assert、uri的音频数据、pcm数据,我这里因为是为了后面音视频做铺垫,所以加入了ffmpeg来解码音频数据得到pcm数据后,扔到opensl缓存队列就可以了。
具体的解码过程如下:
extern "C"
//int createFFmpegAudioPlay(const char *file_name) {
int Java_com_lake_ndkaudiotest_MainActivity_play(JNIEnv *env, jobject thiz, jstring url) {
isEnd = false;
int i;
AVCodec *pCodec;
//读取输入的音频文件地址
const char *file_name = env->GetStringUTFChars(url, NULL);
LOGI("file_name:%s\n", file_name);
//初始化
av_register_all();
//分配一个AVFormatContext结构
pFormatCtx = avformat_alloc_context();
//打开文件
if (avformat_open_input(&pFormatCtx, file_name, NULL, NULL) != 0) {
LOGE("Couldn't open input stream.\n");
return -1;
}
//查找文件的流信息
if (avformat_find_stream_info(pFormatCtx, NULL) < 0) {
LOGE("Couldn't find stream information.\n");
return -1;
}
//在流信息中找到音频流
audioindex = -1;
for (i = 0; i < pFormatCtx->nb_streams; i++) {
if (pFormatCtx->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
audioindex = i;
break;
}
}
if (audioindex == -1) {
LOGE("Couldn't find a video stream.\n");
return -1;
}
iTotalSeconds = (int) pFormatCtx->duration / 1000000;
//获取相应音频流的解码器
AVCodecParameters *pCodecPar = pFormatCtx->streams[audioindex]->codecpar;
pCodec = avcodec_find_decoder(pCodecPar->codec_id);
assert(pCodec != NULL);
pCodecCtx = avcodec_alloc_context3(pCodec);
// Copy context
if (avcodec_parameters_to_context(pCodecCtx, pCodecPar) != 0) {
fprintf(stderr, "Couldn't copy codec context");
return -1; // Error copying codec context
}
//打开解码器
if (avcodec_open2(pCodecCtx, pCodec, NULL) < 0) {
LOGE("Couldn't open codec.\n");
return -1;
}
//分配一个帧指针,指向解码后的原始帧
pFrame = av_frame_alloc();
//设置格式转换
swr = swr_alloc();
swr = swr_alloc_set_opts(NULL,
pCodecCtx->channel_layout,
AV_SAMPLE_FMT_S16,
pCodecCtx->sample_rate,
pCodecCtx->channel_layout,
pCodecCtx->sample_fmt,
pCodecCtx->sample_rate,
0, NULL);
if (!swr || swr_init(swr) < 0) {
swr_free(&swr);
return -1;
}
swr_init(swr);
//分配输入缓存
int outputBufferSize = 8192;
outputBuffer = (uint8_t *) malloc(sizeof(uint8_t) * outputBufferSize);
// 创建播放引擎
createEngine();
// 创建缓冲队列音频播放器
createBufferQueueAudioPlayer(pCodecCtx->sample_rate, pCodecCtx->channels);
// 启动音频播放
bqPlayerCallback(bqPlayerBufferQueue, NULL);
return 0;
}
opensl获取pcm数据方法
/**
* 读取pcm数据
* @return
*/
int getPCM() {
while (av_read_frame(pFormatCtx, &packet) >= 0) {
if (packet.stream_index == audioindex) {
int ret = avcodec_send_packet(pCodecCtx, &packet);
timestamp = packet.pts * av_q2d(pFormatCtx->streams[audioindex]->time_base);
if (ret < 0 && ret != AVERROR(EAGAIN) && ret != AVERROR_EOF)
break;
ret = avcodec_receive_frame(pCodecCtx, pFrame);
if (ret < 0 && ret != AVERROR_EOF)
break;
//处理不同的格式
if (pCodecCtx->sample_fmt == AV_SAMPLE_FMT_S16P) {
nextSize = av_samples_get_buffer_size(pFrame->linesize, pCodecCtx->channels,
pCodecCtx->frame_size, pCodecCtx->sample_fmt,
1);
} else {
av_samples_get_buffer_size(&nextSize, pCodecCtx->channels, pCodecCtx->frame_size,
pCodecCtx->sample_fmt, 1);
}
// 音频格式转换
swr_convert(swr, &outputBuffer, pFrame->nb_samples,
(uint8_t const **) (pFrame->extended_data),
pFrame->nb_samples);
nextBuffer = outputBuffer;
av_packet_unref(&packet);
return 0;
}
av_packet_unref(&packet);//packet不用了一定要释放掉内存,网上很多例子的内存溢出就是因为没有释放packet的内存。
}
LOGI("getPCM_shutdown");
return -1;
}
有了以上方法,例子参考,基本播放音频是没有问题了。其余的问题都是看个人需求了,我这里就把我的做法分享一下,由于本人c不是太好,虽然实现了,但是从架构上不清楚是不是这样做合不合理,仅供大家参考。
我先说一下我的需求,c层音频播放出来了,但是在java层,我想显示时间,还有控制音频的播放/暂停,以及seek拖动控制,播放完成自动跳下一首。
一开始,我试了一下opensl本身seek功能,结果获取seek接口就失败了,不得不从ffmpeg解码层考虑seek功能,还好,找到了ffmpeg的seek功能,实现起来完全没有问题,后面的视频seek可以参考一下。
其实就是调用以下方法
//跳转的位置(秒为单位)
int64_t seek_pos = (int64_t) (seekTime /av_q2d(pFormatCtx->streams[audioindex]->time_base));
//跳转方法 音频跳转非常快,没有延迟感
if (av_seek_frame(pFormatCtx, audioindex, seek_pos, AVSEEK_FLAG_BACKWARD) < 0) {
LOGE("%s, av_seek_frame() seek to %.3f failed!", __FUNCTION__,(double) seek_pos / AV_TIME_BASE);
return -2;
}
//清空buffer
avcodec_flush_buffers(pCodecCtx);
时间位置获取也非常简单,根据packet获取就可以了
timestamp = packet.pts * av_q2d(pFormatCtx->streams[audioindex]->time_base);
然后java层来调用以下c层实现的seek方法就可以了
然后下来就时间的回调,之前想直接在回调函数里去调java层的方法,但是回调触发到第二遍的时候,就报错了,不知道是不是JNIEnv使用的关系,但是搞了半天就是不可以,没办法,只能自己起一个方法,用一个while循环去监听我所需要回调的数据,然后在这个while里去调java的方法就不会崩溃,所以想直接在opensl的回调方法去调用java层方法感觉有点不科学,不知道能不能实现。
extern "C"
void Java_com_lake_ndkaudiotest_MainActivity_showtime(JNIEnv *env, jobject thiz) {
int seconds = -1;
int totalSeconds = -1;
bool end = false;
jclass jclazz = env->GetObjectClass(thiz);
jmethodID jmethodIDS = env->GetMethodID(jclazz, "showTime", "(I)V");
jmethodID jmethodIDT = env->GetMethodID(jclazz, "setToatalTime", "(I)V");
jmethodID jmethodIDE = env->GetMethodID(jclazz, "isPlayEnd", "(Z)V");
// make sure the asset audio player was created
// seek
while (true) {
if (timestamp != -1) {
//告诉java 音频播放当前时间
if (seconds != timestamp) {
seconds = timestamp;
env->CallVoidMethod(thiz, jmethodIDS, (jint) timestamp);
}
}
if (iTotalSeconds != -1) {
//告诉java 音频总时间
if (totalSeconds != iTotalSeconds) {
totalSeconds = iTotalSeconds;
env->CallVoidMethod(thiz, jmethodIDT, (jint) iTotalSeconds);
}
}
if (isEnd != end) {
//告诉java层 音频播放完成
end = isEnd;
env->CallVoidMethod(thiz, jmethodIDE, (jboolean) isEnd);
}
usleep(100000);//睡0.1秒 不然一直死循环非常占用cpu资源
}
}
这里利用了监听全局变量,只要一变化就调用java层方法。
java层根据传过来的参数再进行其他处理。
java层代码:
package com.lake.ndkaudiotest;
import android.content.Context;
import android.graphics.Color;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.SeekBar;
import android.widget.TextView;
import java.io.File;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private SeekBar mSeekBar;
private Thread timeThread;
private int mProgress;//播放进度
private ListView listview;
private TextView tVTime;//当前时间
private TextView tVName;//名称
private TextView tTTime;//总时间
private int toTalTime;//总时间
private Button mBtnPlayOrPause;
private Button mBtnLast;
private Button mBtnNext;
private String inputurl;//文件路径
boolean isFirst = true;
private int curItem = 0;//当前序号
boolean playing = false;//播放状态
private int length = 0;//列表长度
// Used to load the 'native-lib' library on application startup.
static {
System.loadLibrary("native-lib");
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
mSeekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
@Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
Log.e("lake", "onProgressChanged: " + progress);
mProgress = progress;
}
@Override
public void onStartTrackingTouch(SeekBar seekBar) {
pause(true);
}
@Override
public void onStopTrackingTouch(SeekBar seekBar) {
seek(mProgress);
}
});
}
/**
* 界面初始化
*/
private void initView() {
listview = findViewById(R.id.listview);
tVName = findViewById(R.id.filename);
tVTime = findViewById(R.id.showtime);
tTTime = findViewById(R.id.totaltime);
mSeekBar = findViewById(R.id.seekbar);
mBtnPlayOrPause = findViewById(R.id.playorpause);
mBtnLast = findViewById(R.id.last);
mBtnNext = findViewById(R.id.next);
mBtnPlayOrPause.setOnClickListener(this);
mBtnLast.setOnClickListener(this);
mBtnNext.setOnClickListener(this);
final String folderurl = Environment.getExternalStorageDirectory().getPath();
final File[] files = new File(folderurl + "/MyLocalPlayer").listFiles();
length = files.length;
final ListFileAdapter myListAdapter = new ListFileAdapter(this, files);
listview.setAdapter(myListAdapter);
listview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
curItem = position;
myListAdapter.setSelectItem(position);
myListAdapter.notifyDataSetInvalidated();
inputurl = folderurl + "/MyLocalPlayer/" + files[position].getName();
tVName.setText(files[position].getName().substring(0,files[position].getName().length()-4));
if (!isFirst) {
stop();
mSeekBar.setProgress(0);
}
play(inputurl);
if (isFirst) {
isFirst = false;
timeThread = new Thread(new Runnable() {
@Override
public void run() {
showtime();
}
});
timeThread.start();
}
pause(!playing);
}
});
clickListItem(curItem);
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.playorpause://播放或者暂停
pause(playing);
mBtnPlayOrPause.setText(playing ? "Play" : "Pause");
playing = !playing;
break;
case R.id.last: {
//上一首
int item = (curItem - 1) < 0 ? length-1 : curItem - 1;
clickListItem(item);
break;
}
case R.id.next: {
//下一首
int item = (curItem + 1) >= length ? 0 : curItem + 1;
clickListItem(item);
break;
}
default:
break;
}
}
/**
* 点击列表
* @param position 第几项
*/
public void clickListItem(int position){
AdapterView.OnItemClickListener onItemClickListener = listview.getOnItemClickListener();
if (onItemClickListener != null) {
onItemClickListener.onItemClick(listview, null, position, position);
listview.setSelection(position);
}
}
/**
* 关闭播放器
*/
public void shutdown() {
stop();
mSeekBar.setProgress(0);
play(inputurl);
}
/**
* 显示实时进度时间
*
* @param time
*/
public void showTime(final int time) {
final String n = resetTimeInt(time / 3600) + ":" + resetTimeInt(time % 3600 / 60) + ":" + resetTimeInt(time % 60);
runOnUiThread(new Runnable() {
@Override
public void run() {
tVTime.setText(n);
mSeekBar.setProgress(time);
}
});
Log.e("lake", "showTime: " + n);
}
/**
* 设置总时间
*
* @param total
*/
public void setToatalTime(int total) {
toTalTime = total;
mSeekBar.setMax(total);
Log.e("lake", "toTalTime: " + toTalTime);
final String t = resetTimeInt(total / 3600) + ":" + resetTimeInt(total % 3600 / 60) + ":" + resetTimeInt(total % 60);
runOnUiThread(new Runnable() {
@Override
public void run() {
tTTime.setText(t);
}
});
}
/**
* 播放结束
*
* @param isEnd
*/
public void isPlayEnd(boolean isEnd) {
Log.e("lake", "isPlayEnd: " + isEnd);
if (isEnd) {
runOnUiThread(new Runnable() {
@Override
public void run() {
int item = (curItem + 1) >= length ? 0 : curItem + 1;
clickListItem(item);
}
});
}
}
public native void play(String url);
public native void stop();
public native void pause(boolean play);
public native void seek(int seekTime);
public native void showtime();
public String resetTimeInt(int time) {
if (time < 10) {
return "0" + time;
} else {
return time + "";
}
}
class ListFileAdapter extends BaseAdapter {
private Context context;
private File[] files;
public ListFileAdapter(Context context, File[] files) {
this.context = context;
this.files = files;
}
@Override
public int getCount() {
return files.length;
}
@Override
public Object getItem(int position) {
return files[position];
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder viewHolder = null;
if (convertView == null) {
viewHolder = new ViewHolder();
convertView = LayoutInflater.from(context).inflate(R.layout.list_item, null);
viewHolder.mTextView = (TextView) convertView.findViewById(R.id.filename);
convertView.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) convertView.getTag();
}
viewHolder.mTextView.setText(files[position].getName());
if (position == selectItem) {
convertView.setBackgroundColor(Color.GRAY);
} else {
convertView.setBackgroundColor(Color.WHITE);
}
return convertView;
}
class ViewHolder {
TextView mTextView;
}
public void setSelectItem(int selectItem) {
this.selectItem = selectItem;
}
private int selectItem = -1;
}
}
大概就是这样。
实现的demo下载地址:https://github.com/lakehubo/NDKAudioTest
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文章浏览阅读8.3k次,点赞6次,收藏80次。Python科学计算基础库:Numpy,Pandas,Scipy,Matplotlib1.NumPy支持大量的维度数组与矩阵运算,此外也针对数组运算提供大量的数学函数库,线性代数,傅里叶变换和随机数功能底层使用C语言编写,内部解除了GIL(全局解释器锁),其对数组的操作速度不受Python解释器的限制,效率远高于纯Python代码。2.PandasPandas是一个强大的基于Numpy分析结构化数据的工具集;Pandas 可以从各种文件格式比如 CSV、JSON、SQL、Micros_python常用库介绍
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文章浏览阅读955次,点赞12次,收藏32次。有时我们在磁盘规划前会想要确定一下当前系统的文件系统或磁盘分区情况。这时,就有几个命令可以供选择,通过本文,可以学习这些命令的使用。_lsblk
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文章浏览阅读419次,点赞16次,收藏3次。此外,中科数安防泄密软件还具有智能加密功能,可以识别散落在企业不同位置的机密文件,并对其强制加密,非核心数据不被过分加密,防止敏感内容泄漏。同时,它还支持离网办公,针对出差人员或网络故障等原因引起的客户端离网,用户可以发起离网审批,确保终端密文在出差过程中保持可用状态,不影响正常办公。它采用了多种加密机制和技术手段,确保企业数据的安全性、完整性和机密性。总之,中科数安防泄密软件是一种功能强大、技术先进的企业数据保护软件,可以有效地防止敏感数据的泄露和非法访问,保障企业的信息安全和业务连续性。