/* * dtsdec.c : free DTS Coherent Acoustics stream decoder. * Copyright (C) 2004 Benjamin Zores <ben@geexbox.org> * * This file is part of libavcodec. * * This library 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 library 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., 675 Mass Ave, Cambridge, MA 02139, USA. */#ifdef HAVE_AV_CONFIG_H#undef HAVE_AV_CONFIG_H#endif#include "avcodec.h"#include <dts.h>#include <stdlib.h>#include <string.h>#ifdef HAVE_MALLOC_H#include <malloc.h>#endif#define INBUF_SIZE 4096#define BUFFER_SIZE 4096#define HEADER_SIZE 14#ifdef LIBDTS_FIXED#define CONVERT_LEVEL (1 << 26)#define CONVERT_BIAS 0#else#define CONVERT_LEVEL 1#define CONVERT_BIAS 384#endifstatic inlineint16_t convert (int32_t i){#ifdef LIBDTS_FIXED    i >>= 15;#else    i -= 0x43c00000;#endif    return (i > 32767) ? 32767 : ((i < -32768) ? -32768 : i);}voidconvert2s16_2 (sample_t * _f, int16_t * s16){  int i;  int32_t * f = (int32_t *) _f;  for (i = 0; i < 256; i++)    {      s16[2*i] = convert (f[i]);      s16[2*i+1] = convert (f[i+256]);    }}voidconvert2s16_4 (sample_t * _f, int16_t * s16){  int i;  int32_t * f = (int32_t *) _f;  for (i = 0; i < 256; i++)    {      s16[4*i] = convert (f[i]);      s16[4*i+1] = convert (f[i+256]);      s16[4*i+2] = convert (f[i+512]);      s16[4*i+3] = convert (f[i+768]);    }}voidconvert2s16_5 (sample_t * _f, int16_t * s16){  int i;  int32_t * f = (int32_t *) _f;  for (i = 0; i < 256; i++)    {      s16[5*i] = convert (f[i]);      s16[5*i+1] = convert (f[i+256]);      s16[5*i+2] = convert (f[i+512]);      s16[5*i+3] = convert (f[i+768]);      s16[5*i+4] = convert (f[i+1024]);    }}static voidconvert2s16_multi (sample_t * _f, int16_t * s16, int flags){  int i;  int32_t * f = (int32_t *) _f;  switch (flags)    {    case DTS_MONO:      for (i = 0; i < 256; i++)        {          s16[5*i] = s16[5*i+1] = s16[5*i+2] = s16[5*i+3] = 0;          s16[5*i+4] = convert (f[i]);        }      break;    case DTS_CHANNEL:    case DTS_STEREO:    case DTS_DOLBY:      convert2s16_2 (_f, s16);      break;    case DTS_3F:      for (i = 0; i < 256; i++)        {          s16[5*i] = convert (f[i]);          s16[5*i+1] = convert (f[i+512]);          s16[5*i+2] = s16[5*i+3] = 0;          s16[5*i+4] = convert (f[i+256]);        }      break;    case DTS_2F2R:      convert2s16_4 (_f, s16);      break;    case DTS_3F2R:      convert2s16_5 (_f, s16);      break;    case DTS_MONO | DTS_LFE:      for (i = 0; i < 256; i++)        {          s16[6*i] = s16[6*i+1] = s16[6*i+2] = s16[6*i+3] = 0;          s16[6*i+4] = convert (f[i+256]);          s16[6*i+5] = convert (f[i]);        }      break;    case DTS_CHANNEL | DTS_LFE:    case DTS_STEREO | DTS_LFE:    case DTS_DOLBY | DTS_LFE:      for (i = 0; i < 256; i++)        {          s16[6*i] = convert (f[i+256]);          s16[6*i+1] = convert (f[i+512]);          s16[6*i+2] = s16[6*i+3] = s16[6*i+4] = 0;          s16[6*i+5] = convert (f[i]);        }      break;    case DTS_3F | DTS_LFE:      for (i = 0; i < 256; i++)        {          s16[6*i] = convert (f[i+256]);          s16[6*i+1] = convert (f[i+768]);          s16[6*i+2] = s16[6*i+3] = 0;          s16[6*i+4] = convert (f[i+512]);          s16[6*i+5] = convert (f[i]);        }      break;    case DTS_2F2R | DTS_LFE:      for (i = 0; i < 256; i++)        {          s16[6*i] = convert (f[i+256]);          s16[6*i+1] = convert (f[i+512]);          s16[6*i+2] = convert (f[i+768]);          s16[6*i+3] = convert (f[i+1024]);          s16[6*i+4] = 0;          s16[6*i+5] = convert (f[i]);        }      break;    case DTS_3F2R | DTS_LFE:      for (i = 0; i < 256; i++)        {          s16[6*i] = convert (f[i+256]);          s16[6*i+1] = convert (f[i+768]);          s16[6*i+2] = convert (f[i+1024]);          s16[6*i+3] = convert (f[i+1280]);          s16[6*i+4] = convert (f[i+512]);          s16[6*i+5] = convert (f[i]);        }      break;    }}static intchannels_multi (int flags){  if (flags & DTS_LFE)    return 6;  else if (flags & 1)   /* center channel */    return 5;  else if ((flags & DTS_CHANNEL_MASK) == DTS_2F2R)    return 4;  else    return 2;}static intdts_decode_frame (AVCodecContext *avctx, void *data, int *data_size,                  uint8_t *buff, int buff_size){  uint8_t * start = buff;  uint8_t * end = buff + buff_size;  static uint8_t buf[BUFFER_SIZE];  static uint8_t * bufptr = buf;  static uint8_t * bufpos = buf + HEADER_SIZE;  static int sample_rate;  static int frame_length;  static int flags;  int bit_rate;  int len;  dts_state_t *state = avctx->priv_data;  *data_size = 0;  while (1)    {      len = end - start;      if (!len)        break;      if (len > bufpos - bufptr)        len = bufpos - bufptr;      memcpy (bufptr, start, len);      bufptr += len;      start += len;      if (bufptr == bufpos)        {          if (bufpos == buf + HEADER_SIZE)            {              int length;              length = dts_syncinfo (state, buf, &flags, &sample_rate,                                     &bit_rate, &frame_length);              if (!length)                {                  av_log (NULL, AV_LOG_INFO, "skip\n");                  for (bufptr = buf; bufptr < buf + HEADER_SIZE-1; bufptr++)                    bufptr[0] = bufptr[1];                  continue;                }              bufpos = buf + length;            }          else            {              level_t level;              sample_t bias;              int i;              flags = 2; /* ???????????? */              level = CONVERT_LEVEL;              bias = CONVERT_BIAS;              flags |= DTS_ADJUST_LEVEL;              if (dts_frame (state, buf, &flags, &level, bias))                goto error;              avctx->sample_rate = sample_rate;              avctx->channels = channels_multi (flags);              avctx->bit_rate = bit_rate;              for (i = 0; i < dts_blocks_num (state); i++)                {                  if (dts_block (state))                    goto error;                  {                    int chans;                    chans = channels_multi (flags);                    convert2s16_multi (dts_samples (state), data,                                       flags & (DTS_CHANNEL_MASK | DTS_LFE));                    data += 256 * sizeof (int16_t) * chans;                    *data_size += 256 * sizeof (int16_t) * chans;                  }                }              bufptr = buf;              bufpos = buf + HEADER_SIZE;              continue;            error:              av_log (NULL, AV_LOG_ERROR, "error\n");              bufptr = buf;              bufpos = buf + HEADER_SIZE;            }        }    }  return buff_size;}static intdts_decode_init (AVCodecContext *avctx){  avctx->priv_data = dts_init (0);  if (avctx->priv_data == NULL)    return 1;  return 0;}static intdts_decode_end (AVCodecContext *s){  return 0;}AVCodec dts_decoder = {  "dts",  CODEC_TYPE_AUDIO,  CODEC_ID_DTS,  sizeof (dts_state_t *),  dts_decode_init,  NULL,  dts_decode_end,  dts_decode_frame,};