C++ Filter::clear方法代码示例

  PosibErr<void> setup_filter(Filter & filter, 
			      Config * config, 
			      bool use_decoder, bool use_filter, bool use_encoder)
  {
    StringList sl;
    config->retrieve_list("filter", &sl);
    StringListEnumeration els = sl.elements_obj();
    const char * filter_name;
    String fun;

    StackPtr<IndividualFilter> ifilter;

    filter.clear();

    while ((filter_name = els.next()) != 0) {
      //fprintf(stderr, "Loading %s ... \n", filter_name);
      FilterEntry * f = get_standard_filter(filter_name);
      // In case libdl is not available a filter is only available if made
      // one of the standard filters. This is done by statically linking
      // the filter sources.
      // On systems providing libdl or in case libtool mimics libdl 
      // The following code parts assure that all filters needed and requested
      // by user are loaded properly or be reported to be missing.
      // 
      FilterHandle decoder_handle, filter_handle, encoder_handle;
#ifdef HAVE_LIBDL
      FilterEntry dynamic_filter;
      if (!f) {

        RET_ON_ERR_SET(get_dynamic_filter(config, filter_name),
                       const ConfigModule *, module);

        if (!(decoder_handle = dlopen(module->file,RTLD_NOW)) ||
            !(encoder_handle = dlopen(module->file,RTLD_NOW)) ||
            !(filter_handle  = dlopen(module->file,RTLD_NOW)))
          return make_err(cant_dlopen_file,dlerror()).with_file(filter_name);

        fun = "new_aspell_";
        fun += filter_name;
        fun += "_decoder";
        dynamic_filter.decoder = (FilterFun *)dlsym(decoder_handle.get(), fun.str());

        fun = "new_aspell_";
        fun += filter_name;
        fun += "_encoder";
        dynamic_filter.encoder = (FilterFun *)dlsym(encoder_handle.get(), fun.str());

        fun = "new_aspell_";
        fun += filter_name;
        fun += "_filter";
        dynamic_filter.filter = (FilterFun *)dlsym(filter_handle.get(), fun.str());

        if (!dynamic_filter.decoder && 
	    !dynamic_filter.encoder &&
	    !dynamic_filter.filter)
          return make_err(empty_filter,filter_name);
        dynamic_filter.name = filter_name;
        f = &dynamic_filter;
      } 
#else
      if (!f)
        return make_err(no_such_filter, filter_name);
#endif
      if (use_decoder && f->decoder && (ifilter = f->decoder())) {
        RET_ON_ERR_SET(ifilter->setup(config), bool, keep);
        ifilter->handle = decoder_handle.release();
	if (!keep) {
	  ifilter.del();
	} else {
          filter.add_filter(ifilter.release());
        }
      } 
      if (use_filter && f->filter && (ifilter = f->filter())) {
        RET_ON_ERR_SET(ifilter->setup(config), bool, keep);
        ifilter->handle = filter_handle.release();
        if (!keep) {
          ifilter.del();
        } else {
          filter.add_filter(ifilter.release());
        }
      }

//.........这里部分代码省略.........
                vector <MessageAudio>::iterator audio;
                audio = vAudioQueue.begin();
                do {
                    LOG4CXX_INFO(narratorLog, "Saying: " << audio->getText());

                    AudioStream *audioStream;

                    std::string encoding = ((MessageAudio&)*audio).getEncoding();
                    if (encoding == "ogg")
                    {
                        audioStream = new OggStream;
                    }
                    else if (encoding == "mp3")
                    {
                        audioStream = new Mp3Stream;
                    }
                    else
                    {
                        LOG4CXX_ERROR(narratorLog, "encoding '" << encoding << "' not supported");
                        audio++;
                        continue;
                    }

                    if(!audioStream->open(*audio)) {
                        LOG4CXX_ERROR(narratorLog, "error opening audio stream");
                        audioStream->close();
                        break;
                    }

                    if (portaudio.getRate() != audioStream->getRate())
                    {
                        long waitms = portaudio.getRemainingms();
                        if (waitms != 0)
                        {
                            LOG4CXX_DEBUG(narratorLog, "Waiting for current playback to finish");
                            while (waitms > 0)
                            {
                                usleep(100000);
                                waitms -= 100;
                            }
                        }
                    }

                    if(!portaudio.open(audioStream->getRate(), audioStream->getChannels())) {
                        LOG4CXX_ERROR(narratorLog, "error initializing portaudio");
                        break;
                    }

                    if(!filter.open(audioStream->getRate(), audioStream->getChannels())) {
                        LOG4CXX_ERROR(narratorLog, "error initializing filter");
                        break;
                    }


                    int inSamples = 0;
                    soundtouch::SAMPLETYPE* buffer = new soundtouch::SAMPLETYPE[audioStream->getChannels()*BUFFERSIZE];

                    do {
                        // change gain, tempo and pitch
                        adjustGainTempoPitch(n, filter, gain, tempo, pitch);

                        // read some stuff from the audio stream
                        inSamples = audioStream->read(buffer, BUFFERSIZE*audioStream->getChannels());

                        if(inSamples != 0) {
                            filter.write(buffer, inSamples);
                            writeSamplesToPortaudio( n, portaudio, filter, buffer );
                        } else {
                            LOG4CXX_INFO(narratorLog, "Flushing soundtouch buffer");
                            filter.flush();
                        }

                        state = n->getState();

                    } while (inSamples != 0 && state == Narrator::PLAY && !n->bResetFlag);

                    if(buffer != NULL) delete [] (buffer);
                    audioStream->close();
                    audio++;

                } while(audio != vAudioQueue.end() && state == Narrator::PLAY && !n->bResetFlag);
            }
            //Cleanup message object
            delete(pi.mMessage);
        }

        // Abort stream?
        if(n->bResetFlag) {
            n->bResetFlag = false;
            portaudio.stop();
            filter.clear();
        }

    } while(state != Narrator::EXIT);

    LOG4CXX_INFO(narratorLog, "Shutting down playbackthread");

    pthread_exit(NULL);
    return NULL;
}