你好，我一直在寻找一种方法play and recordLinux（最好是 Ubuntu）系统上的音频。我目前正在开发一个前端语音识别工具包 https://www.launchpad.net/cmusphinx-train这将自动执行调整语音模型所需的几个步骤PocketSphinx and Julius.
音频输入/输出替代方式的建议是welcome，以及修复错误如下所示.
这是我迄今为止用来播放的当前代码.WAV file:
void Engine::sayText ( const string OutputText ) {
string audioUri = "temp.wav";
string requestUri = this->getRequestUri( OPENMARY_PROCESS , OutputText.c_str( ) );
int error , audioStream;
pa_simple *pulseConnection;
pa_sample_spec simpleSpecs;
simpleSpecs.format = PA_SAMPLE_S16LE;
simpleSpecs.rate = 44100;
simpleSpecs.channels = 2;
eprintf( E_MESSAGE , "Generating audio for '%s' from '%s'..." , OutputText.c_str( ) , requestUri.c_str( ) );
FILE* audio = this->getHttpFile( requestUri , audioUri );
fclose(audio);
eprintf( E_MESSAGE , "Generated audio.");
if ( ( audioStream = open( audioUri.c_str( ) , O_RDONLY ) ) < 0 ) {
fprintf( stderr , __FILE__": open() failed: %s\n" , strerror( errno ) );
goto finish;
}
if ( dup2( audioStream , STDIN_FILENO ) < 0 ) {
fprintf( stderr , __FILE__": dup2() failed: %s\n" , strerror( errno ) );
goto finish;
}
close( audioStream );
pulseConnection = pa_simple_new( NULL , "AudioPush" , PA_STREAM_PLAYBACK , NULL , "openMary C++" , &simpleSpecs , NULL , NULL , &error );
for (int i = 0;;i++ ) {
const int bufferSize = 1024;
uint8_t audioBuffer[bufferSize];
ssize_t r;
eprintf( E_MESSAGE , "Buffering %d..",i);
/* Read some data ... */
if ( ( r = read( STDIN_FILENO , audioBuffer , sizeof (audioBuffer ) ) ) <= 0 ) {
if ( r == 0 ) /* EOF */
break;
eprintf( E_ERROR , __FILE__": read() failed: %s\n" , strerror( errno ) );
if ( pulseConnection )
pa_simple_free( pulseConnection );
}
/* ... and play it */
if ( pa_simple_write( pulseConnection , audioBuffer , ( size_t ) r , &error ) < 0 ) {
fprintf( stderr , __FILE__": pa_simple_write() failed: %s\n" , pa_strerror( error ) );
if ( pulseConnection )
pa_simple_free( pulseConnection );
}
usleep(2);
}
/* Make sure that every single sample was played */
if ( pa_simple_drain( pulseConnection , &error ) < 0 ) {
fprintf( stderr , __FILE__": pa_simple_drain() failed: %s\n" , pa_strerror( error ) );
if ( pulseConnection )
pa_simple_free( pulseConnection );
}
}
注意：如果您想要此文件的其余代码，您可以下载它here http://launchpad.net/libopenmary-c++/trunk/0.3a/+download/libopenmary_0%2Bbzr20110123%2B4.tar.gz直接从启动板。
更新：我尝试使用GStreamermm，这行不通：
Glib::RefPtr<Pipeline> pipeline;
Glib::RefPtr<Element> sink, filter, source;
Glib::RefPtr<Gio::File> audioSrc = Gio::File::create_for_path(uri);
pipeline = Pipeline::create("audio-playback");
source = ElementFactory::create_element("alsasrc","source");
filter = ElementFactory::create_element("identity","filter");
sink = ElementFactory::create_element("alsasink","sink");
//sink->get_property("file",audioSrc);
if (!source || !filter || !sink){
showErrorDialog("Houston!","We got a problem.");
return;
}
pipeline->add(source)->add(filter)->add(sink);
source->link(sink);
pipeline->set_state(Gst::STATE_PLAYING);
showInformation("Close this to stop recording");
pipeline->set_state(Gst::STATE_PAUSED);
