/* * L3_compress: * ------------ */ void L3_compress(config_t *config) { int frames_processed; int channel; int i; int gr; double pe[2][2]; short *buffer_window[2]; double avg_slots_per_frame; double frac_slots_per_frame; long whole_slots_per_frame; double slot_lag; int mean_bits; int sideinfo_len; static short buffer[2][samp_per_frame]; static int l3_enc[2][2][samp_per_frame2]; static long l3_sb_sample[2][3][18][SBLIMIT]; static long mdct_freq[2][2][samp_per_frame2]; static L3_psy_ratio_t ratio; static L3_side_info_t side_info; static L3_scalefac_t scalefactor; static bitstream_t bs; open_bit_stream_w(&bs, config->outfile, BUFFER_SIZE); memset((char *)&side_info,0,sizeof(L3_side_info_t)); L3_subband_initialise(); L3_mdct_initialise(); L3_loop_initialise(); config->mpeg.samples_per_frame = samp_per_frame; config->mpeg.total_frames = config->wave.total_samples/config->mpeg.samples_per_frame; config->mpeg.bits_per_slot = 8; frames_processed = 0; sideinfo_len = (config->wave.channels==1) ? 168 : 288; /* Figure average number of 'slots' per frame. */ avg_slots_per_frame = ((double)config->mpeg.samples_per_frame / ((double)config->wave.samplerate/1000)) * ((double)config->mpeg.bitr / (double)config->mpeg.bits_per_slot); whole_slots_per_frame = (int)avg_slots_per_frame; frac_slots_per_frame = avg_slots_per_frame - (double)whole_slots_per_frame; slot_lag = -frac_slots_per_frame; if(frac_slots_per_frame==0) config->mpeg.padding = 0; while(config->get_pcm(buffer, config)) { update_status(++frames_processed, config); buffer_window[0] = buffer[0]; buffer_window[1] = buffer[1]; if(frac_slots_per_frame) { if(slot_lag>(frac_slots_per_frame-1.0)) { /* No padding for this frame */ slot_lag -= frac_slots_per_frame; config->mpeg.padding = 0; } else { /* Padding for this frame */ slot_lag += (1-frac_slots_per_frame); config->mpeg.padding = 1; } } config->mpeg.bits_per_frame = 8*(whole_slots_per_frame + config->mpeg.padding); mean_bits = (config->mpeg.bits_per_frame - sideinfo_len)>>1; /* polyphase filtering */ for(gr=0;gr<2;gr++) for(channel=config->wave.channels; channel--; ) for(i=0;i<18;i++) L3_window_filter_subband(&buffer_window[channel], &l3_sb_sample[channel][gr+1][i][0] ,channel); /* apply mdct to the polyphase output */ L3_mdct_sub(l3_sb_sample, mdct_freq, config); /* bit and noise allocation */ L3_iteration_loop(pe,mdct_freq,&ratio,&side_info, l3_enc, mean_bits,&scalefactor, config); /* write the frame to the bitstream */ L3_format_bitstream(l3_enc,&side_info,&scalefactor, &bs,mdct_freq,NULL,0, config); } close_bit_stream(&bs); }
/*! Compress a given smplFrame at a given bitRate * * \param smplFrame a buffer containing samples to be compressed to layer3 * \param cfg pointer to an initialized config_t structure * \param bitRate bitRate to encode sample at * \return status : * - 0 => Success * < 0 => any error code */ int kb_mp3_Compress( unsigned short *smplFrame, unsigned long smplNmbr, struct config_t *cfg, int bitRate, char *filePath ) { int frames_processed; int channel; int i; int gr; double pe[2][2]; short *buffer_window[2]; double avg_slots_per_frame; double frac_slots_per_frame; long whole_slots_per_frame; double slot_lag; int mean_bits; int sideinfo_len; static short buffer[2][samp_per_frame]; static int l3_enc[2][2][samp_per_frame2]; static long l3_sb_sample[2][3][18][SBLIMIT]; static long mdct_freq[2][2][samp_per_frame2]; static L3_psy_ratio_t ratio; static L3_side_info_t side_info; static L3_scalefac_t scalefactor; static bitstream_t bs; if(cfg) cfg->mpeg.bitr = bitRate; /* Override the default bitRate */ if(filePath && cfg) cfg->outfile = filePath; else return -1; /* outfile related error */ open_bit_stream_w(&bs, cfg->outfile, BUFFER_SIZE); memset((char *)&side_info,0,sizeof(L3_side_info_t)); /* some mpeg layer 3 initialisations */ L3_subband_initialise(); L3_mdct_initialise(); L3_loop_initialise(); cfg->mpeg.samples_per_frame = samp_per_frame; cfg->mpeg.total_frames = smplNmbr /cfg->mpeg.samples_per_frame; cfg->mpeg.bits_per_slot = 8; frames_processed = 0; sideinfo_len = 288; /* Stereo assumed */ /* (config.wave.channels==1) ? 168 : 288; */ /* Figure average number of 'slots' per frame. */ avg_slots_per_frame = ((double)cfg->mpeg.samples_per_frame / ((double)smplNmbr/1000)) * ((double)cfg->mpeg.bitr / (double)cfg->mpeg.bits_per_slot); whole_slots_per_frame = (int)avg_slots_per_frame; frac_slots_per_frame = avg_slots_per_frame - (double)whole_slots_per_frame; slot_lag = -frac_slots_per_frame; if(frac_slots_per_frame==0) cfg->mpeg.padding = 0; //while(wave_get(buffer)) for( i = 0; i < smplNmbr; i++) { kb_mp3_updStatus(cfg, ++frames_processed); buffer_window[0] = buffer[0]; buffer_window[1] = buffer[1]; if(frac_slots_per_frame) if(slot_lag>(frac_slots_per_frame-1.0)) { /* No padding for this frame */ slot_lag -= frac_slots_per_frame; cfg->mpeg.padding = 0; } else { /* Padding for this frame */ slot_lag += (1-frac_slots_per_frame); cfg->mpeg.padding = 1; } cfg->mpeg.bits_per_frame = 8*(whole_slots_per_frame + cfg->mpeg.padding); mean_bits = (cfg->mpeg.bits_per_frame - sideinfo_len)>>1; /* polyphase filtering */ for(gr=0;gr<2;gr++) for(channel=2; channel-- ; ) /* assumed stereo */ /* for(channel=cfg->wave.channels; channel--; ) */ for(i=0;i<18;i++) L3_window_filter_subband(&buffer_window[channel], &l3_sb_sample[channel][gr+1][i][0] ,channel); /* apply mdct to the polyphase output */ L3_mdct_sub(cfg, l3_sb_sample, mdct_freq); /* bit and noise allocation */ L3_iteration_loop(cfg, pe,mdct_freq,&ratio,&side_info, l3_enc, mean_bits,&scalefactor); /* write the frame to the bitstream */ L3_format_bitstream(cfg, l3_enc,&side_info,&scalefactor, &bs,mdct_freq,NULL,0); } close_bit_stream(&bs); }
MP3Stream::MP3Stream(StreamsManager *pStreamsManager, string name) : BaseAudioStream(pStreamsManager, ST_IN_AUDIO_MP3, name) { BaseAudioDevice *pAudioCapDevice= reinterpret_cast<BaseAudioDevice*> (HardwareManager::GetHardwareInstance(HT_MIC)); _pMP3streamCapabilities= new StreamCapabilities(); //pcmbuf = new uint8_t (PCM_PAGE_SIZE); //mp3 config L3_set_config_mpeg_defaults(&_mp3config.mpeg); //wave config _sampleRate = pAudioCapDevice->GetSampleRate(); _numOfChannel = pAudioCapDevice->GetNumberOfChannels(); _bitsPerSample = pAudioCapDevice->GetBitsPerSample(); _bitRate = _mp3config.mpeg.bitr;// //set wave type, TODO: removed _mp3config.wave.type = WAVE_RIFF_PCM; _mp3config.wave.channels = _numOfChannel; //mono _mp3config.wave.samplerate = _sampleRate; _mp3config.wave.bits = _bitsPerSample; //config sample rate index, and bit rate _mp3config.mpeg.samplerate_index = L3_find_samplerate_index(_sampleRate, _mp3config.mpeg.type); if ( _mp3config.mpeg.samplerate_index < 0) FATAL ("invalid sample rate in mp3stream ctor"); //TODO: should throw an execption _mp3config.mpeg.bitrate_index = L3_find_bitrate_index(_mp3config.mpeg.bitr, _mp3config.mpeg.type); if (_mp3config.mpeg.bitrate_index < 0) FATAL ("invliad bit rate in mpstream ctor"); open_bit_stream_w(&_bs, BITSSIZE); memset ((char*) &_side_info, 0, sizeof(L3_side_info_t)); L3_subband_initialise(); L3_mdct_initialise(); L3_loop_initialise(); _mp3config.mpeg.mode_gr = (_mp3config.mpeg.type==1)? 2: 1; _samplesInput = _mp3config.mpeg.samples_per_frame = (_mp3config.mpeg.type==1)? 1152:576; //config->mpeg.total_frames = (); _mp3config.mpeg.bits_per_slot = 8; _sideinfo_len = 32; if (_mp3config.mpeg.type==1) { if (_numOfChannel==1) _sideinfo_len += 136; else _sideinfo_len += 256; } else { //mpeg2 if (_numOfChannel==1) _sideinfo_len += 72; else _sideinfo_len += 136; } if (_mp3config.mpeg.crc) _sideinfo_len += 16; _avg_slots_per_frame = ((double)_samplesInput / ((double)_sampleRate/1000)) * ((double)_bitRate / (double)_mp3config.mpeg.bits_per_slot); _whole_slots_per_frame = (int)_avg_slots_per_frame; _frac_slots_per_frame = _avg_slots_per_frame - (double)_whole_slots_per_frame; _slot_lag = -_frac_slots_per_frame; if (_frac_slots_per_frame==0) _mp3config.mpeg.padding = 0; DEBUG ("mp3 stream info: _sideinfo_len:%d sampleInput:%d bitRate:%d sampleRate:%d avg slots per frame:%d", _sideinfo_len, _samplesInput, _bitRate, _sampleRate, _avg_slots_per_frame); GETTIMESTAMP(ats); mp3Duration=(1000.0/(double)_sampleRate)*(double)(_samplesInput/_numOfChannel); //m second _pMP3streamCapabilities->aac.InitAACCapability(_sampleRate, _numOfChannel, _bitsPerSample, (samplesInput/_numOfChannel), (_bitRate* 1000 *_numOfChannel), mp3Duration); //bitrate: 2 channel _pMP3streamCapabilities->audioCodecId = CODEC_AUDIO_MP3; #ifdef MP3STREAM_DEBUG if((pfOutputMP3=fopen("MICOut.mp3", "wb")) == NULL){ FATAL("Open output file 'MICOut.mp3' fail... !!\n"); exit(1); } if((pfPCM=fopen("MICOut.wav", "wb")) == NULL){ FATAL("Open output file 'MICOut.mp3' fail... !!\n"); exit(1); } DEBUG("Initial MP3Stream End..!!\n"); #endif }