ref: f5010739d787dab0e31623439911ba35d977c23e
dir: /libfaac/frame.c/
/* * FAAC - Freeware Advanced Audio Coder * Copyright (C) 2001 Menno Bakker * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * * $Id: frame.c,v 1.15 2001/03/12 20:12:37 menno Exp $ */ /* * CHANGES: * 2001/01/17: menno: Added frequency cut off filter. * 2001/02/28: menno: Added Temporal Noise Shaping. * 2001/03/05: menno: Added Long Term Prediction. * */ #include <stdio.h> #include <stdlib.h> #include "frame.h" #include "coder.h" #include "joint.h" #include "channels.h" #include "bitstream.h" #include "filtbank.h" #include "aacquant.h" #include "util.h" #include "huffman.h" #include "psych.h" #include "tns.h" #include "ltp.h" faacEncConfigurationPtr FAACAPI faacEncGetCurrentConfiguration(faacEncHandle hEncoder) { faacEncConfigurationPtr config = &(hEncoder->config); return config; } int FAACAPI faacEncSetConfiguration(faacEncHandle hEncoder, faacEncConfigurationPtr config) { hEncoder->config.allowMidside = config->allowMidside; hEncoder->config.useLfe = config->useLfe; hEncoder->config.useTns = config->useTns; hEncoder->config.useLtp = config->useLtp; hEncoder->config.aacProfile = config->aacProfile; /* No SSR supported yet */ if ((hEncoder->config.aacProfile != MAIN)&&(hEncoder->config.aacProfile != LOW)) return 0; /* Re-init TNS for new profile */ TnsInit(hEncoder); /* Check for correct bitrate */ if (config->bitRate > MaxBitrate(hEncoder->sampleRate)) return 0; if (config->bitRate < MinBitrate()) return 0; /* Bitrate check passed */ hEncoder->config.bitRate = config->bitRate; /* OK */ return 1; } faacEncHandle FAACAPI faacEncOpen(unsigned long sampleRate, unsigned int numChannels, unsigned long *inputSamples, unsigned long *maxOutputBytes) { unsigned int channel; faacEncHandle hEncoder; *inputSamples = 1024*numChannels; *maxOutputBytes = (6144/8)*numChannels; hEncoder = (faacEncStruct*)AllocMemory(sizeof(faacEncStruct)); SetMemory(hEncoder, 0, sizeof(faacEncStruct)); hEncoder->numChannels = numChannels; hEncoder->sampleRate = sampleRate; hEncoder->sampleRateIdx = GetSRIndex(sampleRate); /* Initialize variables to default values */ hEncoder->frameNum = 0; hEncoder->flushFrame = 0; /* Default configuration */ hEncoder->config.aacProfile = MAIN; hEncoder->config.allowMidside = 1; hEncoder->config.useLfe = 0; hEncoder->config.useTns = 0; hEncoder->config.useLtp = 0; hEncoder->config.bitRate = 64000; /* default bitrate / channel */ hEncoder->config.bandWidth = 18000; /* default bandwidth */ /* find correct sampling rate depending parameters */ hEncoder->srInfo = &srInfo[hEncoder->sampleRateIdx]; for (channel = 0; channel < numChannels; channel++) { hEncoder->coderInfo[channel].prev_window_shape = SINE_WINDOW; hEncoder->coderInfo[channel].window_shape = SINE_WINDOW; hEncoder->coderInfo[channel].block_type = ONLY_LONG_WINDOW; hEncoder->coderInfo[channel].num_window_groups = 1; hEncoder->coderInfo[channel].window_group_length[0] = 1; hEncoder->sampleBuff[channel] = NULL; hEncoder->nextSampleBuff[channel] = NULL; hEncoder->next2SampleBuff[channel] = NULL; hEncoder->ltpTimeBuff[channel] = (double*)AllocMemory(2*BLOCK_LEN_LONG*sizeof(double)); SetMemory(hEncoder->ltpTimeBuff[channel], 0, 2*BLOCK_LEN_LONG*sizeof(double)); } /* Initialize coder functions */ PsyInit(&hEncoder->gpsyInfo, hEncoder->psyInfo, hEncoder->numChannels, hEncoder->sampleRate, hEncoder->sampleRateIdx); FilterBankInit(hEncoder); TnsInit(hEncoder); LtpInit(hEncoder); AACQuantizeInit(hEncoder->coderInfo, hEncoder->numChannels); HuffmanInit(hEncoder->coderInfo, hEncoder->numChannels); /* Return handle */ return hEncoder; } int FAACAPI faacEncClose(faacEncHandle hEncoder) { unsigned int channel; /* Deinitialize coder functions */ PsyEnd(&hEncoder->gpsyInfo, hEncoder->psyInfo, hEncoder->numChannels); FilterBankEnd(hEncoder); LtpEnd(hEncoder); AACQuantizeEnd(hEncoder->coderInfo, hEncoder->numChannels); HuffmanEnd(hEncoder->coderInfo, hEncoder->numChannels); /* Free remaining buffer memory */ for (channel = 0; channel < hEncoder->numChannels; channel++) { if (hEncoder->ltpTimeBuff[channel]) FreeMemory(hEncoder->ltpTimeBuff[channel]); if (hEncoder->sampleBuff[channel]) FreeMemory(hEncoder->sampleBuff[channel]); if (hEncoder->nextSampleBuff[channel]) FreeMemory(hEncoder->nextSampleBuff[channel]); } /* Free handle */ if (hEncoder) FreeMemory(hEncoder); return 0; } int FAACAPI faacEncEncode(faacEncHandle hEncoder, short *inputBuffer, unsigned int samplesInput, unsigned char *outputBuffer, unsigned int bufferSize ) { unsigned int channel, i; int sb, frameBytes; unsigned int bitsToUse, offset; BitStream *bitStream; /* bitstream used for writing the frame to */ TnsInfo *tnsInfo_for_LTP; TnsInfo *tnsDecInfo; /* local copy's of parameters */ ChannelInfo *channelInfo = hEncoder->channelInfo; CoderInfo *coderInfo = hEncoder->coderInfo; unsigned int numChannels = hEncoder->numChannels; unsigned int sampleRate = hEncoder->sampleRate; unsigned int aacProfile = hEncoder->config.aacProfile; unsigned int useLfe = hEncoder->config.useLfe; unsigned int useTns = hEncoder->config.useTns; unsigned int useLtp = hEncoder->config.useLtp; unsigned int allowMidside = hEncoder->config.allowMidside; unsigned int bitRate = hEncoder->config.bitRate; unsigned int bandWidth = hEncoder->config.bandWidth; /* Increase frame number */ hEncoder->frameNum++; if (samplesInput == 0) hEncoder->flushFrame++; /* After 2 flush frames all samples have been encoded, return 0 bytes written */ if (hEncoder->flushFrame == 2) return 0; /* Determine the channel configuration */ GetChannelInfo(channelInfo, numChannels, useLfe); /* Update current sample buffers */ for (channel = 0; channel < numChannels; channel++) { if (hEncoder->sampleBuff[channel]) { for(i = 0; i < FRAME_LEN; i++) { hEncoder->ltpTimeBuff[channel][i] = hEncoder->sampleBuff[channel][i]; } } if (hEncoder->nextSampleBuff[channel]) { for(i = 0; i < FRAME_LEN; i++) { hEncoder->ltpTimeBuff[channel][FRAME_LEN + i] = hEncoder->nextSampleBuff[channel][i]; } } if (hEncoder->sampleBuff[channel]) FreeMemory(hEncoder->sampleBuff[channel]); hEncoder->sampleBuff[channel] = hEncoder->nextSampleBuff[channel]; hEncoder->nextSampleBuff[channel] = (double*)AllocMemory(FRAME_LEN*sizeof(double)); if (samplesInput == 0) { /* start flushing*/ for (i = 0; i < FRAME_LEN; i++) hEncoder->nextSampleBuff[channel][i] = 0.0; } else { for (i = 0; i < (int)(samplesInput/numChannels); i++) hEncoder->nextSampleBuff[channel][i] = (double)inputBuffer[(i*numChannels)+channel]; for (i = (int)(samplesInput/numChannels); i < FRAME_LEN; i++) hEncoder->nextSampleBuff[channel][i] = 0.0; } /* Psychoacoustics */ /* Update buffers and run FFT on new samples */ PsyBufferUpdate(&hEncoder->gpsyInfo, &hEncoder->psyInfo[channel], hEncoder->nextSampleBuff[channel]); } if (hEncoder->frameNum <= 1) /* Still filling up the buffers */ return 0; /* Psychoacoustics */ PsyCalculate(channelInfo, &hEncoder->gpsyInfo, hEncoder->psyInfo, hEncoder->srInfo->cb_width_long, hEncoder->srInfo->num_cb_long, hEncoder->srInfo->cb_width_short, hEncoder->srInfo->num_cb_short, numChannels); BlockSwitch(coderInfo, hEncoder->psyInfo, numChannels); /* AAC Filterbank, MDCT with overlap and add */ for (channel = 0; channel < numChannels; channel++) { int k; FilterBank(hEncoder, &coderInfo[channel], hEncoder->sampleBuff[channel], hEncoder->freqBuff[channel], hEncoder->overlapBuff[channel], MOVERLAPPED); if (coderInfo[channel].block_type == ONLY_SHORT_WINDOW) { for (k = 0; k < 8; k++) { specFilter(hEncoder->freqBuff[channel]+k*BLOCK_LEN_SHORT, sampleRate, bandWidth, BLOCK_LEN_SHORT); } } else { specFilter(hEncoder->freqBuff[channel], sampleRate, bandWidth, BLOCK_LEN_LONG); } } /* TMP: Build sfb offset table and other stuff */ for (channel = 0; channel < numChannels; channel++) { channelInfo[channel].msInfo.is_present = 0; if (coderInfo[channel].block_type == ONLY_SHORT_WINDOW) { coderInfo[channel].max_sfb = hEncoder->srInfo->num_cb_short; coderInfo[channel].nr_of_sfb = hEncoder->srInfo->num_cb_short; coderInfo[channel].num_window_groups = 1; coderInfo[channel].window_group_length[0] = 8; coderInfo[channel].window_group_length[1] = 0; coderInfo[channel].window_group_length[2] = 0; coderInfo[channel].window_group_length[3] = 0; coderInfo[channel].window_group_length[4] = 0; coderInfo[channel].window_group_length[5] = 0; coderInfo[channel].window_group_length[6] = 0; coderInfo[channel].window_group_length[7] = 0; offset = 0; for (sb = 0; sb < coderInfo[channel].nr_of_sfb; sb++) { coderInfo[channel].sfb_offset[sb] = offset; offset += hEncoder->srInfo->cb_width_short[sb]; } coderInfo[channel].sfb_offset[coderInfo[channel].nr_of_sfb] = offset; } else { coderInfo[channel].max_sfb = hEncoder->srInfo->num_cb_long; coderInfo[channel].nr_of_sfb = hEncoder->srInfo->num_cb_long; coderInfo[channel].num_window_groups = 1; coderInfo[channel].window_group_length[0] = 1; offset = 0; for (sb = 0; sb < coderInfo[channel].nr_of_sfb; sb++) { coderInfo[channel].sfb_offset[sb] = offset; offset += hEncoder->srInfo->cb_width_long[sb]; } coderInfo[channel].sfb_offset[coderInfo[channel].nr_of_sfb] = offset; } } /* Perform TNS analysis and filtering */ for (channel = 0; channel < numChannels; channel++) { if ((!channelInfo[channel].lfe) && (useTns)) { TnsEncode(&(coderInfo[channel].tnsInfo), coderInfo[channel].max_sfb, coderInfo[channel].max_sfb, coderInfo[channel].block_type, coderInfo[channel].sfb_offset, hEncoder->freqBuff[channel]); } else { coderInfo[channel].tnsInfo.tnsDataPresent = 0; /* TNS not used for LFE */ } } for(channel = 0; channel < numChannels; channel++) { if((coderInfo[channel].tnsInfo.tnsDataPresent != 0) && (useTns)) tnsInfo_for_LTP = &(coderInfo[channel].tnsInfo); else tnsInfo_for_LTP = NULL; if(channelInfo[channel].present && (!channelInfo[channel].lfe) && (coderInfo[channel].block_type != ONLY_SHORT_WINDOW) && (useLtp)) { LtpEncode(hEncoder, &coderInfo[channel], &(coderInfo[channel].ltpInfo), tnsInfo_for_LTP, hEncoder->freqBuff[channel], hEncoder->ltpTimeBuff[channel]); } else { coderInfo[channel].ltpInfo.global_pred_flag = 0; } } MSEncode(coderInfo, channelInfo, hEncoder->freqBuff, numChannels, allowMidside); /* Quantize and code the signal */ bitsToUse = (int)(bitRate*FRAME_LEN/sampleRate+0.5); for (channel = 0; channel < numChannels; channel++) { if (coderInfo[channel].block_type == ONLY_SHORT_WINDOW) { AACQuantize(&coderInfo[channel], &hEncoder->psyInfo[channel], &channelInfo[channel], hEncoder->srInfo->cb_width_short, hEncoder->srInfo->num_cb_short, hEncoder->freqBuff[channel], bitsToUse); } else { AACQuantize(&coderInfo[channel], &hEncoder->psyInfo[channel], &channelInfo[channel], hEncoder->srInfo->cb_width_long, hEncoder->srInfo->num_cb_long, hEncoder->freqBuff[channel], bitsToUse); } } MSReconstruct(coderInfo, channelInfo, numChannels); for (channel = 0; channel < numChannels; channel++) { /* If short window, reconstruction not needed for prediction */ if ((coderInfo[channel].block_type == ONLY_SHORT_WINDOW)) { int sind; for (sind = 0; sind < 1024; sind++) { coderInfo[channel].requantFreq[sind] = 0.0; } } else { if((coderInfo[channel].tnsInfo.tnsDataPresent != 0) && (useTns)) tnsDecInfo = &(coderInfo[channel].tnsInfo); else tnsDecInfo = NULL; if ((!channelInfo[channel].lfe) && (useLtp)) { /* no reconstruction needed for LFE channel*/ LtpReconstruct(&coderInfo[channel], &(coderInfo[channel].ltpInfo), coderInfo[channel].requantFreq); if(tnsDecInfo != NULL) TnsDecodeFilterOnly(&(coderInfo[channel].tnsInfo), coderInfo[channel].nr_of_sfb, coderInfo[channel].max_sfb, coderInfo[channel].block_type, coderInfo[channel].sfb_offset, coderInfo[channel].requantFreq); IFilterBank(hEncoder, &coderInfo[channel], coderInfo[channel].requantFreq, coderInfo[channel].ltpInfo.time_buffer, coderInfo[channel].ltpInfo.ltp_overlap_buffer, MOVERLAPPED); LtpUpdate(&(coderInfo[channel].ltpInfo), coderInfo[channel].ltpInfo.time_buffer, coderInfo[channel].ltpInfo.ltp_overlap_buffer, BLOCK_LEN_LONG); } } } /* Write the AAC bitstream */ bitStream = OpenBitStream(bufferSize, outputBuffer); WriteBitstream(hEncoder, coderInfo, channelInfo, bitStream, numChannels); /* Close the bitstream and return the number of bytes written */ frameBytes = CloseBitStream(bitStream); #ifdef _DEBUG printf("%4d %4d\n", hEncoder->frameNum-1, frameBytes); #endif return frameBytes; } /* Scalefactorband data table */ static SR_INFO srInfo[12+1] = { { 96000, 41, 12, { 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 8, 8, 8, 8, 8, 12, 12, 12, 12, 12, 16, 16, 24, 28, 36, 44, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64 },{ 4, 4, 4, 4, 4, 4, 8, 8, 8, 16, 28, 36 } }, { 88200, 41, 12, { 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 8, 8, 8, 8, 8, 12, 12, 12, 12, 12, 16, 16, 24, 28, 36, 44, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64 },{ 4, 4, 4, 4, 4, 4, 8, 8, 8, 16, 28, 36 } }, { 64000, 47, 12, { 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 8, 8, 8, 8, 12, 12, 12, 16, 16, 16, 20, 24, 24, 28, 36, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40, 40 },{ 4, 4, 4, 4, 4, 4, 8, 8, 8, 16, 28, 32 } }, { 48000, 49, 14, { 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 8, 8, 8, 8, 8, 8, 8, 12, 12, 12, 12, 16, 16, 20, 20, 24, 24, 28, 28, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 96 }, { 4, 4, 4, 4, 4, 8, 8, 8, 12, 12, 12, 16, 16, 16 } }, { 44100, 49, 14, { 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 8, 8, 8, 8, 8, 8, 8, 12, 12, 12, 12, 16, 16, 20, 20, 24, 24, 28, 28, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 96 }, { 4, 4, 4, 4, 4, 8, 8, 8, 12, 12, 12, 16, 16, 16 } }, { 32000, 51, 14, { 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 8, 8, 8, 8, 8, 8, 8, 12, 12, 12, 12, 16, 16, 20, 20, 24, 24, 28, 28, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32 },{ 4, 4, 4, 4, 4, 8, 8, 8, 12, 12, 12, 16, 16, 16 } }, { 24000, 47, 15, { 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 12, 12, 12, 12, 16, 16, 16, 20, 20, 24, 24, 28, 28, 32, 36, 36, 40, 44, 48, 52, 52, 64, 64, 64, 64, 64 }, { 4, 4, 4, 4, 4, 4, 4, 8, 8, 8, 12, 12, 16, 16, 20 } }, { 22050, 47, 15, { 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 12, 12, 12, 12, 16, 16, 16, 20, 20, 24, 24, 28, 28, 32, 36, 36, 40, 44, 48, 52, 52, 64, 64, 64, 64, 64 }, { 4, 4, 4, 4, 4, 4, 4, 8, 8, 8, 12, 12, 16, 16, 20 } }, { 16000, 43, 15, { 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 12, 12, 12, 12, 12, 12, 12, 12, 12, 16, 16, 16, 16, 20, 20, 20, 24, 24, 28, 28, 32, 36, 40, 40, 44, 48, 52, 56, 60, 64, 64, 64 }, { 4, 4, 4, 4, 4, 4, 4, 4, 8, 8, 12, 12, 16, 20, 20 } }, { 12000, 43, 15, { 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 12, 12, 12, 12, 12, 12, 12, 12, 12, 16, 16, 16, 16, 20, 20, 20, 24, 24, 28, 28, 32, 36, 40, 40, 44, 48, 52, 56, 60, 64, 64, 64 }, { 4, 4, 4, 4, 4, 4, 4, 4, 8, 8, 12, 12, 16, 20, 20 } }, { 11025, 43, 15, { 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 12, 12, 12, 12, 12, 12, 12, 12, 12, 16, 16, 16, 16, 20, 20, 20, 24, 24, 28, 28, 32, 36, 40, 40, 44, 48, 52, 56, 60, 64, 64, 64 }, { 4, 4, 4, 4, 4, 4, 4, 4, 8, 8, 12, 12, 16, 20, 20 } }, { 8000, 40, 15, { 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 16, 16, 16, 16, 16, 16, 16, 20, 20, 20, 20, 24, 24, 24, 28, 28, 32, 32, 36, 40, 44, 48, 52, 56, 60, 64, 80 }, { 4, 4, 4, 4, 4, 4, 4, 8, 8, 8, 8, 12, 16, 20, 20 } }, { -1 } };