fdk-aac/libAACenc/src/mps_main.cpp

/* -----------------------------------------------------------------------------
Software License for The Fraunhofer FDK AAC Codec Library for Android

© Copyright  1995 - 2018 Fraunhofer-Gesellschaft zur Förderung der angewandten
Forschung e.V. All rights reserved.

 1.    INTRODUCTION
The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software
that implements the MPEG Advanced Audio Coding ("AAC") encoding and decoding
scheme for digital audio. This FDK AAC Codec software is intended to be used on
a wide variety of Android devices.

AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient
general perceptual audio codecs. AAC-ELD is considered the best-performing
full-bandwidth communications codec by independent studies and is widely
deployed. AAC has been standardized by ISO and IEC as part of the MPEG
specifications.

Patent licenses for necessary patent claims for the FDK AAC Codec (including
those of Fraunhofer) may be obtained through Via Licensing
(www.vialicensing.com) or through the respective patent owners individually for
the purpose of encoding or decoding bit streams in products that are compliant
with the ISO/IEC MPEG audio standards. Please note that most manufacturers of
Android devices already license these patent claims through Via Licensing or
directly from the patent owners, and therefore FDK AAC Codec software may
already be covered under those patent licenses when it is used for those
licensed purposes only.

Commercially-licensed AAC software libraries, including floating-point versions
with enhanced sound quality, are also available from Fraunhofer. Users are
encouraged to check the Fraunhofer website for additional applications
information and documentation.

2.    COPYRIGHT LICENSE

Redistribution and use in source and binary forms, with or without modification,
are permitted without payment of copyright license fees provided that you
satisfy the following conditions:

You must retain the complete text of this software license in redistributions of
the FDK AAC Codec or your modifications thereto in source code form.

You must retain the complete text of this software license in the documentation
and/or other materials provided with redistributions of the FDK AAC Codec or
your modifications thereto in binary form. You must make available free of
charge copies of the complete source code of the FDK AAC Codec and your
modifications thereto to recipients of copies in binary form.

The name of Fraunhofer may not be used to endorse or promote products derived
from this library without prior written permission.

You may not charge copyright license fees for anyone to use, copy or distribute
the FDK AAC Codec software or your modifications thereto.

Your modified versions of the FDK AAC Codec must carry prominent notices stating
that you changed the software and the date of any change. For modified versions
of the FDK AAC Codec, the term "Fraunhofer FDK AAC Codec Library for Android"
must be replaced by the term "Third-Party Modified Version of the Fraunhofer FDK
AAC Codec Library for Android."

3.    NO PATENT LICENSE

NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without
limitation the patents of Fraunhofer, ARE GRANTED BY THIS SOFTWARE LICENSE.
Fraunhofer provides no warranty of patent non-infringement with respect to this
software.

You may use this FDK AAC Codec software or modifications thereto only for
purposes that are authorized by appropriate patent licenses.

4.    DISCLAIMER

This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright
holders and contributors "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,
including but not limited to the implied warranties of merchantability and
fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary,
or consequential damages, including but not limited to procurement of substitute
goods or services; loss of use, data, or profits, or business interruption,
however caused and on any theory of liability, whether in contract, strict
liability, or tort (including negligence), arising in any way out of the use of
this software, even if advised of the possibility of such damage.

5.    CONTACT INFORMATION

Fraunhofer Institute for Integrated Circuits IIS
Attention: Audio and Multimedia Departments - FDK AAC LL
Am Wolfsmantel 33
91058 Erlangen, Germany

www.iis.fraunhofer.de/amm
amm-info@iis.fraunhofer.de
----------------------------------------------------------------------------- */

/**************************** AAC encoder library ******************************

   Author(s):   Markus Lohwasser

   Description: Mpeg Surround library interface functions

*******************************************************************************/

/* Includes ******************************************************************/
#include "mps_main.h"
#include "sacenc_lib.h"

/* Data Types ****************************************************************/
struct MPS_ENCODER {
  HANDLE_MP4SPACE_ENCODER hSacEncoder;

  AUDIO_OBJECT_TYPE audioObjectType;

  FDK_bufDescr inBufDesc;
  FDK_bufDescr outBufDesc;
  SACENC_InArgs inargs;
  SACENC_OutArgs outargs;

  void *pInBuffer[1];
  UINT pInBufferSize[1];
  UINT pInBufferElSize[1];
  UINT pInBufferType[1];

  void *pOutBuffer[2];
  UINT pOutBufferSize[2];
  UINT pOutBufferElSize[2];
  UINT pOutBufferType[2];

  UCHAR sacOutBuffer[1024]; /* Worst case memory consumption for ELDv2: 768
                               bytes => 6144 bits (Core + SBR + MPS) */
};

struct MPS_CONFIG_TAB {
  AUDIO_OBJECT_TYPE audio_object_type;
  CHANNEL_MODE channel_mode;
  ULONG sbr_ratio;
  ULONG sampling_rate;
  ULONG bitrate_min;
  ULONG bitrate_max;
};

/* Constants *****************************************************************/
static const MPS_CONFIG_TAB mpsConfigTab[] = {
    {AOT_ER_AAC_ELD, MODE_212, 0, 16000, 16000, 39999},
    {AOT_ER_AAC_ELD, MODE_212, 0, 22050, 16000, 49999},
    {AOT_ER_AAC_ELD, MODE_212, 0, 24000, 16000, 61999},
    {AOT_ER_AAC_ELD, MODE_212, 0, 32000, 20000, 84999},
    {AOT_ER_AAC_ELD, MODE_212, 0, 44100, 50000, 192000},
    {AOT_ER_AAC_ELD, MODE_212, 0, 48000, 62000, 192000},

    {AOT_ER_AAC_ELD, MODE_212, 1, 16000, 18000, 31999},
    {AOT_ER_AAC_ELD, MODE_212, 1, 22050, 18000, 31999},
    {AOT_ER_AAC_ELD, MODE_212, 1, 24000, 20000, 64000},

    {AOT_ER_AAC_ELD, MODE_212, 2, 32000, 18000, 64000},
    {AOT_ER_AAC_ELD, MODE_212, 2, 44100, 21000, 64000},
    {AOT_ER_AAC_ELD, MODE_212, 2, 48000, 26000, 64000}

};

/* Function / Class Declarations *********************************************/

/* Function / Class Definition ***********************************************/
static INT FDK_MpegsEnc_WriteFrameHeader(HANDLE_MPS_ENCODER hMpsEnc,
                                         UCHAR *const pOutputBuffer,
                                         const int outputBufferSize);

MPS_ENCODER_ERROR FDK_MpegsEnc_Open(HANDLE_MPS_ENCODER *phMpsEnc) {
  MPS_ENCODER_ERROR error = MPS_ENCODER_OK;
  HANDLE_MPS_ENCODER hMpsEnc = NULL;

  if (phMpsEnc == NULL) {
    error = MPS_ENCODER_INVALID_HANDLE;
    goto bail;
  }

  if (NULL ==
      (hMpsEnc = (HANDLE_MPS_ENCODER)FDKcalloc(1, sizeof(MPS_ENCODER)))) {
    error = MPS_ENCODER_MEMORY_ERROR;
    goto bail;
  }
  FDKmemclear(hMpsEnc, sizeof(MPS_ENCODER));

  if (SACENC_OK != FDK_sacenc_open(&hMpsEnc->hSacEncoder)) {
    error = MPS_ENCODER_MEMORY_ERROR;
    goto bail;
  }

  /* Return mps encoder instance */
  *phMpsEnc = hMpsEnc;

bail:
  if (error != MPS_ENCODER_OK) {
    FDK_MpegsEnc_Close(&hMpsEnc);
  }
  return error;
}

MPS_ENCODER_ERROR FDK_MpegsEnc_Close(HANDLE_MPS_ENCODER *phMpsEnc) {
  MPS_ENCODER_ERROR error = MPS_ENCODER_OK;

  if (phMpsEnc == NULL) {
    error = MPS_ENCODER_INVALID_HANDLE;
    goto bail;
  }

  if (*phMpsEnc != NULL) {
    FDK_sacenc_close(&(*phMpsEnc)->hSacEncoder);
    FDKfree(*phMpsEnc);
    *phMpsEnc = NULL;
  }
bail:
  return error;
}

MPS_ENCODER_ERROR FDK_MpegsEnc_Init(HANDLE_MPS_ENCODER hMpsEnc,
                                    const AUDIO_OBJECT_TYPE audioObjectType,
                                    const UINT samplingrate, const UINT bitrate,
                                    const UINT sbrRatio, const UINT framelength,
                                    const UINT inputBufferSizePerChannel,
                                    const UINT coreCoderDelay) {
  MPS_ENCODER_ERROR error = MPS_ENCODER_OK;
  const UINT fs_low = 27713;  /* low MPS sampling frequencies */
  const UINT fs_high = 55426; /* high MPS sampling frequencies */
  UINT nTimeSlots = 0, nQmfBandsLd = 0;

  if (hMpsEnc == NULL) {
    error = MPS_ENCODER_INVALID_HANDLE;
    goto bail;
  }

  /* Combine MPS with SBR only if the number of QMF band fits together.*/
  switch (sbrRatio) {
    case 1: /* downsampled sbr - 32 QMF bands required */
      if (!(samplingrate < fs_low)) {
        error = MPS_ENCODER_INIT_ERROR;
        goto bail;
      }
      break;
    case 2: /* dualrate - 64 QMF bands required */
      if (!((samplingrate >= fs_low) && (samplingrate < fs_high))) {
        error = MPS_ENCODER_INIT_ERROR;
        goto bail;
      }
      break;
    case 0:
    default:; /* time interface - no samplingrate restriction */
  }

  /* 32  QMF-Bands  ( fs < 27713 )
   * 64  QMF-Bands  ( 27713 >= fs <= 55426 )
   * 128 QMF-Bands  ( fs > 55426 )
   */
  nQmfBandsLd =
      (samplingrate < fs_low) ? 5 : ((samplingrate > fs_high) ? 7 : 6);
  nTimeSlots = framelength >> nQmfBandsLd;

  /* check if number of qmf bands is usable for given framelength */
  if (framelength != (nTimeSlots << nQmfBandsLd)) {
    error = MPS_ENCODER_INIT_ERROR;
    goto bail;
  }

  /* is given bitrate intended to be supported */
  if ((INT)bitrate != FDK_MpegsEnc_GetClosestBitRate(audioObjectType, MODE_212,
                                                     samplingrate, sbrRatio,
                                                     bitrate)) {
    error = MPS_ENCODER_INIT_ERROR;
    goto bail;
  }

  /* init SAC library */
  switch (audioObjectType) {
    case AOT_ER_AAC_ELD: {
      const UINT noInterFrameCoding = 0;

      if ((SACENC_OK !=
           FDK_sacenc_setParam(hMpsEnc->hSacEncoder, SACENC_LOWDELAY,
                               (noInterFrameCoding == 1) ? 1 : 2)) ||
          (SACENC_OK != FDK_sacenc_setParam(hMpsEnc->hSacEncoder,
                                            SACENC_ENC_MODE, SACENC_212)) ||
          (SACENC_OK != FDK_sacenc_setParam(hMpsEnc->hSacEncoder,
                                            SACENC_SAMPLERATE, samplingrate)) ||
          (SACENC_OK != FDK_sacenc_setParam(hMpsEnc->hSacEncoder,
                                            SACENC_FRAME_TIME_SLOTS,
                                            nTimeSlots)) ||
          (SACENC_OK != FDK_sacenc_setParam(hMpsEnc->hSacEncoder,
                                            SACENC_PARAM_BANDS,
                                            SACENC_BANDS_15)) ||
          (SACENC_OK !=
           FDK_sacenc_setParam(hMpsEnc->hSacEncoder, SACENC_TIME_DOM_DMX, 2)) ||
          (SACENC_OK !=
           FDK_sacenc_setParam(hMpsEnc->hSacEncoder, SACENC_COARSE_QUANT, 0)) ||
          (SACENC_OK != FDK_sacenc_setParam(hMpsEnc->hSacEncoder,
                                            SACENC_QUANT_MODE,
                                            SACENC_QUANTMODE_FINE)) ||
          (SACENC_OK != FDK_sacenc_setParam(hMpsEnc->hSacEncoder,
                                            SACENC_TIME_ALIGNMENT, 0)) ||
          (SACENC_OK != FDK_sacenc_setParam(hMpsEnc->hSacEncoder,
                                            SACENC_INDEPENDENCY_FACTOR, 20))) {
        error = MPS_ENCODER_INIT_ERROR;
        goto bail;
      }
      break;
    }
    default:
      error = MPS_ENCODER_INIT_ERROR;
      goto bail;
  }

  if (SACENC_OK != FDK_sacenc_init(hMpsEnc->hSacEncoder, coreCoderDelay)) {
    error = MPS_ENCODER_INIT_ERROR;
  }

  hMpsEnc->audioObjectType = audioObjectType;

  hMpsEnc->inBufDesc.ppBase = (void **)&hMpsEnc->pInBuffer;
  hMpsEnc->inBufDesc.pBufSize = hMpsEnc->pInBufferSize;
  hMpsEnc->inBufDesc.pEleSize = hMpsEnc->pInBufferElSize;
  hMpsEnc->inBufDesc.pBufType = hMpsEnc->pInBufferType;
  hMpsEnc->inBufDesc.numBufs = 1;

  hMpsEnc->outBufDesc.ppBase = (void **)&hMpsEnc->pOutBuffer;
  hMpsEnc->outBufDesc.pBufSize = hMpsEnc->pOutBufferSize;
  hMpsEnc->outBufDesc.pEleSize = hMpsEnc->pOutBufferElSize;
  hMpsEnc->outBufDesc.pBufType = hMpsEnc->pOutBufferType;
  hMpsEnc->outBufDesc.numBufs = 2;

  hMpsEnc->pInBuffer[0] = NULL;
  hMpsEnc->pInBufferSize[0] = 0;
  hMpsEnc->pInBufferElSize[0] = sizeof(INT_PCM);
  hMpsEnc->pInBufferType[0] = (FDK_BUF_TYPE_INPUT | FDK_BUF_TYPE_PCM_DATA);

  hMpsEnc->pOutBuffer[0] = NULL;
  hMpsEnc->pOutBufferSize[0] = 0;
  hMpsEnc->pOutBufferElSize[0] = sizeof(INT_PCM);
  hMpsEnc->pOutBufferType[0] = (FDK_BUF_TYPE_OUTPUT | FDK_BUF_TYPE_PCM_DATA);

  hMpsEnc->pOutBuffer[1] = NULL;
  hMpsEnc->pOutBufferSize[1] = 0;
  hMpsEnc->pOutBufferElSize[1] = sizeof(UCHAR);
  hMpsEnc->pOutBufferType[1] = (FDK_BUF_TYPE_OUTPUT | FDK_BUF_TYPE_BS_DATA);

  hMpsEnc->inargs.isInputInterleaved = 0;
  hMpsEnc->inargs.inputBufferSizePerChannel = inputBufferSizePerChannel;

bail:
  return error;
}

MPS_ENCODER_ERROR FDK_MpegsEnc_Process(HANDLE_MPS_ENCODER hMpsEnc,
                                       INT_PCM *const pAudioSamples,
                                       const INT nAudioSamples,
                                       AACENC_EXT_PAYLOAD *pMpsExtPayload) {
  MPS_ENCODER_ERROR error = MPS_ENCODER_OK;

  if (hMpsEnc == NULL) {
    error = MPS_ENCODER_INVALID_HANDLE;
  } else {
    int sacHeaderFlag = 1;
    int sacOutBufferOffset = 0;

    /* In case of eld the ssc is explicit and doesn't need to be inband */
    if (hMpsEnc->audioObjectType == AOT_ER_AAC_ELD) {
      sacHeaderFlag = 0;
    }

    /* 4 bits nibble after extension type */
    hMpsEnc->sacOutBuffer[0] = (sacHeaderFlag == 0) ? 0x3 : 0x7;
    sacOutBufferOffset += 1;

    if (sacHeaderFlag) {
      sacOutBufferOffset += FDK_MpegsEnc_WriteFrameHeader(
          hMpsEnc, &hMpsEnc->sacOutBuffer[sacOutBufferOffset],
          sizeof(hMpsEnc->sacOutBuffer) - sacOutBufferOffset);
    }

    /* Register input and output buffer. */
    hMpsEnc->pInBuffer[0] = (void *)pAudioSamples;
    hMpsEnc->inargs.nInputSamples = nAudioSamples;

    hMpsEnc->pOutBuffer[0] = (void *)pAudioSamples;
    hMpsEnc->pOutBufferSize[0] = sizeof(INT_PCM) * nAudioSamples / 2;

    hMpsEnc->pOutBuffer[1] = (void *)&hMpsEnc->sacOutBuffer[sacOutBufferOffset];
    hMpsEnc->pOutBufferSize[1] =
        sizeof(hMpsEnc->sacOutBuffer) - sacOutBufferOffset;

    /* encode SAC frame */
    if (SACENC_OK != FDK_sacenc_encode(hMpsEnc->hSacEncoder,
                                       &hMpsEnc->inBufDesc,
                                       &hMpsEnc->outBufDesc, &hMpsEnc->inargs,
                                       &hMpsEnc->outargs)) {
      error = MPS_ENCODER_ENCODE_ERROR;
      goto bail;
    }

    /* export MPS payload */
    pMpsExtPayload->pData = (UCHAR *)hMpsEnc->sacOutBuffer;
    pMpsExtPayload->dataSize =
        hMpsEnc->outargs.nOutputBits + 8 * (sacOutBufferOffset - 1);
    pMpsExtPayload->dataType = EXT_LDSAC_DATA;
    pMpsExtPayload->associatedChElement = -1;
  }

bail:
  return error;
}

INT FDK_MpegsEnc_WriteSpatialSpecificConfig(HANDLE_MPS_ENCODER hMpsEnc,
                                            HANDLE_FDK_BITSTREAM hBs) {
  INT sscBits = 0;

  if (NULL != hMpsEnc) {
    MP4SPACEENC_INFO mp4SpaceEncoderInfo;
    FDK_sacenc_getInfo(hMpsEnc->hSacEncoder, &mp4SpaceEncoderInfo);

    if (hBs != NULL) {
      int i;
      int writtenBits = 0;
      for (i = 0; i<mp4SpaceEncoderInfo.pSscBuf->nSscSizeBits>> 3; i++) {
        FDKwriteBits(hBs, mp4SpaceEncoderInfo.pSscBuf->pSsc[i], 8);
        writtenBits += 8;
      }
      FDKwriteBits(hBs, mp4SpaceEncoderInfo.pSscBuf->pSsc[i],
                   mp4SpaceEncoderInfo.pSscBuf->nSscSizeBits - writtenBits);
    } /* hBS */

    sscBits = mp4SpaceEncoderInfo.pSscBuf->nSscSizeBits;

  } /* valid hMpsEnc */

  return sscBits;
}

static INT FDK_MpegsEnc_WriteFrameHeader(HANDLE_MPS_ENCODER hMpsEnc,
                                         UCHAR *const pOutputBuffer,
                                         const int outputBufferSize) {
  const int sacTimeAlignFlag = 0;

  /* Initialize variables */
  int numBits = 0;

  if ((NULL != hMpsEnc) && (NULL != pOutputBuffer)) {
    UINT alignAnchor, cnt;
    FDK_BITSTREAM Bs;
    FDKinitBitStream(&Bs, pOutputBuffer, outputBufferSize, 0, BS_WRITER);

    /* Calculate SSC length information */
    cnt = (FDK_MpegsEnc_WriteSpatialSpecificConfig(hMpsEnc, NULL) + 7) >> 3;

    /* Write SSC */
    FDKwriteBits(&Bs, sacTimeAlignFlag, 1);

    if (cnt < 127) {
      FDKwriteBits(&Bs, cnt, 7);
    } else {
      FDKwriteBits(&Bs, 127, 7);
      FDKwriteBits(&Bs, cnt - 127, 16);
    }

    alignAnchor = FDKgetValidBits(&Bs);
    FDK_MpegsEnc_WriteSpatialSpecificConfig(hMpsEnc, &Bs);
    FDKbyteAlign(&Bs, alignAnchor); /* bsFillBits */

    if (sacTimeAlignFlag) {
      FDK_ASSERT(1); /* time alignment not supported */
    }

    numBits = FDKgetValidBits(&Bs);
  } /* valid handle */

  return ((numBits + 7) >> 3);
}

INT FDK_MpegsEnc_GetClosestBitRate(const AUDIO_OBJECT_TYPE audioObjectType,
                                   const CHANNEL_MODE channelMode,
                                   const UINT samplingrate, const UINT sbrRatio,
                                   const UINT bitrate) {
  unsigned int i;
  int targetBitrate = -1;

  for (i = 0; i < sizeof(mpsConfigTab) / sizeof(MPS_CONFIG_TAB); i++) {
    if ((mpsConfigTab[i].audio_object_type == audioObjectType) &&
        (mpsConfigTab[i].channel_mode == channelMode) &&
        (mpsConfigTab[i].sbr_ratio == sbrRatio) &&
        (mpsConfigTab[i].sampling_rate == samplingrate)) {
      targetBitrate = fMin(fMax(bitrate, mpsConfigTab[i].bitrate_min),
                           mpsConfigTab[i].bitrate_max);
    }
  }

  return targetBitrate;
}

INT FDK_MpegsEnc_GetDelay(HANDLE_MPS_ENCODER hMpsEnc) {
  INT delay = 0;

  if (NULL != hMpsEnc) {
    MP4SPACEENC_INFO mp4SpaceEncoderInfo;
    FDK_sacenc_getInfo(hMpsEnc->hSacEncoder, &mp4SpaceEncoderInfo);
    delay = mp4SpaceEncoderInfo.nCodecDelay;
  }

  return delay;
}

INT FDK_MpegsEnc_GetDecDelay(HANDLE_MPS_ENCODER hMpsEnc) {
  INT delay = 0;

  if (NULL != hMpsEnc) {
    MP4SPACEENC_INFO mp4SpaceEncoderInfo;
    FDK_sacenc_getInfo(hMpsEnc->hSacEncoder, &mp4SpaceEncoderInfo);
    delay = mp4SpaceEncoderInfo.nDecoderDelay;
  }

  return delay;
}

MPS_ENCODER_ERROR FDK_MpegsEnc_GetLibInfo(LIB_INFO *info) {
  MPS_ENCODER_ERROR error = MPS_ENCODER_OK;

  if (NULL == info) {
    error = MPS_ENCODER_INVALID_HANDLE;
  } else if (SACENC_OK != FDK_sacenc_getLibInfo(info)) {
    error = MPS_ENCODER_INIT_ERROR;
  }

  return error;
}