text: /**
   * @file
   * Vorbis I decoder
   * @author Denes Balatoni  ( dbalatoni programozo hu )
   *
   * This file is part of FFmpeg.
   *
   * FFmpeg is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * FFmpeg 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
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with FFmpeg; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   */
  
  /**
   * @file
   * Vorbis I decoder
   * @author Denes Balatoni  ( dbalatoni programozo hu )
   */
  
  #include <inttypes.h>
  #include <math.h>
  
  #define BITSTREAM_READER_LE
  #include "libavutil/float_dsp.h"
  #include "libavutil/avassert.h"
  #include "avcodec.h"
  #include "get_bits.h"
  #include "fft.h"
  #include "fmtconvert.h"
  #include "internal.h"
  
  #include "vorbis.h"
  #include "vorbisdsp.h"
  #include "xiph.h"
  
  #define V_NB_BITS 8
  #define V_NB_BITS2 11
  #define V_MAX_VLCS (1 << 16)
  #define V_MAX_PARTITIONS (1 << 20)
  
  typedef struct {
      uint8_t      dimensions;
      uint8_t      lookup_type;
      uint8_t      maxdepth;
      VLC          vlc;
      float       *codevectors;
      unsigned int nb_bits;
  } vorbis_codebook;
  
  typedef union  vorbis_floor_u  vorbis_floor_data;
  typedef struct vorbis_floor0_s vorbis_floor0;
  typedef struct vorbis_floor1_s vorbis_floor1;
  struct vorbis_context_s;
  typedef
  int (* vorbis_floor_decode_func)
      (struct vorbis_context_s *, vorbis_floor_data *, float *);
  typedef struct {
      uint8_t floor_type;
      vorbis_floor_decode_func decode;
      union vorbis_floor_u {
          struct vorbis_floor0_s {
              uint8_t       order;
              uint16_t      rate;
              uint16_t      bark_map_size;
              int32_t      *map[2];
              uint32_t      map_size[2];
              uint8_t       amplitude_bits;
              uint8_t       amplitude_offset;
              uint8_t       num_books;
              uint8_t      *book_list;
              float        *lsp;
          } t0;
          struct vorbis_floor1_s {
              uint8_t       partitions;
              uint8_t       partition_class[32];
              uint8_t       class_dimensions[16];
              uint8_t       class_subclasses[16];
              uint8_t       class_masterbook[16];
              int16_t       subclass_books[16][8];
              uint8_t       multiplier;
              uint16_t      x_list_dim;
              vorbis_floor1_entry *list;
          } t1;
      } data;
  } vorbis_floor;
  
  typedef struct {
      uint16_t      type;
      uint32_t      begin;
      uint32_t      end;
      unsigned      partition_size;
      uint8_t       classifications;
      uint8_t       classbook;
      int16_t       books[64][8];
      uint8_t       maxpass;
      uint16_t      ptns_to_read;
      uint8_t      *classifs;
  } vorbis_residue;
  
  typedef struct {
      uint8_t       submaps;
      uint16_t      coupling_steps;
      uint8_t      *magnitude;
      uint8_t      *angle;
      uint8_t      *mux;
      uint8_t       submap_floor[16];
      uint8_t       submap_residue[16];
  } vorbis_mapping;
  
  typedef struct {
      uint8_t       blockflag;
      uint16_t      windowtype;
      uint16_t      transformtype;
      uint8_t       mapping;
  } vorbis_mode;
  
  typedef struct vorbis_context_s {
      AVCodecContext *avctx;
      GetBitContext gb;
      VorbisDSPContext dsp;
      AVFloatDSPContext fdsp;
      FmtConvertContext fmt_conv;
  
      FFTContext mdct[2];
      uint8_t       first_frame;
      uint32_t      version;
      uint8_t       audio_channels;
      uint32_t      audio_samplerate;
      uint32_t      bitrate_maximum;
      uint32_t      bitrate_nominal;
      uint32_t      bitrate_minimum;
      uint32_t      blocksize[2];
      const float  *win[2];
      uint16_t      codebook_count;
      vorbis_codebook *codebooks;
      uint8_t       floor_count;
      vorbis_floor *floors;
      uint8_t       residue_count;
      vorbis_residue *residues;
      uint8_t       mapping_count;
      vorbis_mapping *mappings;
      uint8_t       mode_count;
      vorbis_mode  *modes;
      uint8_t       mode_number; // mode number for the current packet
      int8_t       previous_window;
      float        *channel_residues;
      float        *saved;
  } vorbis_context;
  
  /* Helper functions */
  
  #define BARK(x) \
      (13.1f * atan(0.00074f * (x)) + 2.24f * atan(1.85e-8f * (x) * (x)) + 1e-4f * (x))
  
  static const char idx_err_str[] = "Index value %d out of range (0 - %d) for %s at %s:%i\n";
  #define VALIDATE_INDEX(idx, limit) \
      if (idx >= limit) {\
          av_log(vc->avctx, AV_LOG_ERROR,\
                 idx_err_str,\
                 (int)(idx), (int)(limit - 1), #idx, __FILE__, __LINE__);\
          return AVERROR_INVALIDDATA;\
      }
  #define GET_VALIDATED_INDEX(idx, bits, limit) \
      {\
          idx = get_bits(gb, bits);\
          VALIDATE_INDEX(idx, limit)\
      }
  
  static float vorbisfloat2float(unsigned val)
  {
      double mant = val & 0x1fffff;
      long exp    = (val & 0x7fe00000L) >> 21;
      if (val & 0x80000000)
          mant = -mant;
      return ldexp(mant, exp - 20 - 768);
  }
  
  
  // Free all allocated memory -----------------------------------------
  
  static void vorbis_free(vorbis_context *vc)
  {
      int i;
  
      av_freep(&vc->channel_residues);
      av_freep(&vc->saved);
  
      if (vc->residues)
          for (i = 0; i < vc->residue_count; i++)
              av_free(vc->residues[i].classifs);
      av_freep(&vc->residues);
      av_freep(&vc->modes);
  
      ff_mdct_end(&vc->mdct[0]);
      ff_mdct_end(&vc->mdct[1]);
  
      if (vc->codebooks)
          for (i = 0; i < vc->codebook_count; ++i) {
              av_free(vc->codebooks[i].codevectors);
              ff_free_vlc(&vc->codebooks[i].vlc);
          }
      av_freep(&vc->codebooks);
  
      if (vc->floors)
          for (i = 0; i < vc->floor_count; ++i) {
              if (vc->floors[i].floor_type == 0) {
                  av_free(vc->floors[i].data.t0.map[0]);
                  av_free(vc->floors[i].data.t0.map[1]);
                  av_free(vc->floors[i].data.t0.book_list);
                  av_free(vc->floors[i].data.t0.lsp);
              } else {
                  av_free(vc->floors[i].data.t1.list);
              }
          }
      av_freep(&vc->floors);
  
      if (vc->mappings)
          for (i = 0; i < vc->mapping_count; ++i) {
              av_free(vc->mappings[i].magnitude);
              av_free(vc->mappings[i].angle);
              av_free(vc->mappings[i].mux);
          }
      av_freep(&vc->mappings);
  }
  
  // Parse setup header -------------------------------------------------
  
  // Process codebooks part
  
  static int vorbis_parse_setup_hdr_codebooks(vorbis_context *vc)
  {
      unsigned cb;
      uint8_t  *tmp_vlc_bits  = NULL;
      uint32_t *tmp_vlc_codes = NULL;
      GetBitContext *gb = &vc->gb;
      uint16_t *codebook_multiplicands = NULL;
      int ret = 0;
  
      vc->codebook_count = get_bits(gb, 8) + 1;
  
      av_dlog(NULL, " Codebooks: %d \n", vc->codebook_count);
  
      vc->codebooks = av_mallocz(vc->codebook_count * sizeof(*vc->codebooks));
      tmp_vlc_bits  = av_mallocz(V_MAX_VLCS * sizeof(*tmp_vlc_bits));
      tmp_vlc_codes = av_mallocz(V_MAX_VLCS * sizeof(*tmp_vlc_codes));
      codebook_multiplicands = av_malloc(V_MAX_VLCS * sizeof(*codebook_multiplicands));
      if (!vc->codebooks ||
          !tmp_vlc_bits || !tmp_vlc_codes || !codebook_multiplicands) {
          ret = AVERROR(ENOMEM);
          goto error;
      }
  
      for (cb = 0; cb < vc->codebook_count; ++cb) {
          vorbis_codebook *codebook_setup = &vc->codebooks[cb];
          unsigned ordered, t, entries, used_entries = 0;
  
          av_dlog(NULL, " %u. Codebook\n", cb);
  
          if (get_bits(gb, 24) != 0x564342) {
              av_log(vc->avctx, AV_LOG_ERROR,
                     " %u. Codebook setup data corrupt.\n", cb);
              ret = AVERROR_INVALIDDATA;
              goto error;
          }
  
          codebook_setup->dimensions=get_bits(gb, 16);
          if (codebook_setup->dimensions > 16 || codebook_setup->dimensions == 0) {
              av_log(vc->avctx, AV_LOG_ERROR,
                     " %u. Codebook's dimension is invalid (%d).\n",
                     cb, codebook_setup->dimensions);
              ret = AVERROR_INVALIDDATA;
              goto error;
          }
          entries = get_bits(gb, 24);
          if (entries > V_MAX_VLCS) {
              av_log(vc->avctx, AV_LOG_ERROR,
                     " %u. Codebook has too many entries (%u).\n",
                     cb, entries);
              ret = AVERROR_INVALIDDATA;
              goto error;
          }
  
          ordered = get_bits1(gb);
  
          av_dlog(NULL, " codebook_dimensions %d, codebook_entries %u\n",
                  codebook_setup->dimensions, entries);
  
          if (!ordered) {
              unsigned ce, flag;
              unsigned sparse = get_bits1(gb);
  
              av_dlog(NULL, " not ordered \n");
  
              if (sparse) {
                  av_dlog(NULL, " sparse \n");
  
                  used_entries = 0;
                  for (ce = 0; ce < entries; ++ce) {
                      flag = get_bits1(gb);
                      if (flag) {
                          tmp_vlc_bits[ce] = get_bits(gb, 5) + 1;
                          ++used_entries;
                      } else
                          tmp_vlc_bits[ce] = 0;
                  }
              } else {
                  av_dlog(NULL, " not sparse \n");
  
                  used_entries = entries;
                  for (ce = 0; ce < entries; ++ce)
                      tmp_vlc_bits[ce] = get_bits(gb, 5) + 1;
              }
          } else {
              unsigned current_entry  = 0;
              unsigned current_length = get_bits(gb, 5) + 1;
  
              av_dlog(NULL, " ordered, current length: %u\n", current_length);  //FIXME
  
              used_entries = entries;
              for (; current_entry < used_entries && current_length <= 32; ++current_length) {
                  unsigned i, number;
  
                  av_dlog(NULL, " number bits: %u ", ilog(entries - current_entry));
  
                  number = get_bits(gb, ilog(entries - current_entry));
  
                  av_dlog(NULL, " number: %u\n", number);
  
                  for (i = current_entry; i < number+current_entry; ++i)
                      if (i < used_entries)
                          tmp_vlc_bits[i] = current_length;
  
                  current_entry+=number;
              }
              if (current_entry>used_entries) {
                  av_log(vc->avctx, AV_LOG_ERROR, " More codelengths than codes in codebook. \n");
                  ret = AVERROR_INVALIDDATA;
                  goto error;
              }
          }
  
          codebook_setup->lookup_type = get_bits(gb, 4);
  
          av_dlog(NULL, " lookup type: %d : %s \n", codebook_setup->lookup_type,
                  codebook_setup->lookup_type ? "vq" : "no lookup");
  
  // If the codebook is used for (inverse) VQ, calculate codevectors.
  
          if (codebook_setup->lookup_type == 1) {
              unsigned i, j, k;
              unsigned codebook_lookup_values = ff_vorbis_nth_root(entries, codebook_setup->dimensions);
  
              float codebook_minimum_value = vorbisfloat2float(get_bits_long(gb, 32));
              float codebook_delta_value   = vorbisfloat2float(get_bits_long(gb, 32));
              unsigned codebook_value_bits = get_bits(gb, 4) + 1;
              unsigned codebook_sequence_p = get_bits1(gb);
  
              av_dlog(NULL, " We expect %d numbers for building the codevectors. \n",
                      codebook_lookup_values);
              av_dlog(NULL, "  delta %f minmum %f \n",
                      codebook_delta_value, codebook_minimum_value);
  
              for (i = 0; i < codebook_lookup_values; ++i) {
                  codebook_multiplicands[i] = get_bits(gb, codebook_value_bits);
  
                  av_dlog(NULL, " multiplicands*delta+minmum : %e \n",
                          (float)codebook_multiplicands[i] * codebook_delta_value + codebook_minimum_value);
                  av_dlog(NULL, " multiplicand %u\n", codebook_multiplicands[i]);
              }
  
  // Weed out unused vlcs and build codevector vector
              codebook_setup->codevectors = used_entries ? av_mallocz_array(used_entries,
                                                                      codebook_setup->dimensions *
                                                                      sizeof(*codebook_setup->codevectors))
                                                         : NULL;
              for (j = 0, i = 0; i < entries; ++i) {
                  unsigned dim = codebook_setup->dimensions;
  
                  if (tmp_vlc_bits[i]) {
                      float last = 0.0;
                      unsigned lookup_offset = i;
  
                      av_dlog(vc->avctx, "Lookup offset %u ,", i);
  
                      for (k = 0; k < dim; ++k) {
                          unsigned multiplicand_offset = lookup_offset % codebook_lookup_values;
                          codebook_setup->codevectors[j * dim + k] = codebook_multiplicands[multiplicand_offset] * codebook_delta_value + codebook_minimum_value + last;
                          if (codebook_sequence_p)
                              last = codebook_setup->codevectors[j * dim + k];
                          lookup_offset/=codebook_lookup_values;
                      }
                      tmp_vlc_bits[j] = tmp_vlc_bits[i];
  
                      av_dlog(vc->avctx, "real lookup offset %u, vector: ", j);
                      for (k = 0; k < dim; ++k)
                          av_dlog(vc->avctx, " %f ",
                                  codebook_setup->codevectors[j * dim + k]);
                      av_dlog(vc->avctx, "\n");
  
                      ++j;
                  }
              }
              if (j != used_entries) {
                  av_log(vc->avctx, AV_LOG_ERROR, "Bug in codevector vector building code. \n");
                  ret = AVERROR_INVALIDDATA;
                  goto error;
              }
              entries = used_entries;
          } else if (codebook_setup->lookup_type >= 2) {
              av_log(vc->avctx, AV_LOG_ERROR, "Codebook lookup type not supported. \n");
              ret = AVERROR_INVALIDDATA;
              goto error;
          }
  
  // Initialize VLC table
          if (ff_vorbis_len2vlc(tmp_vlc_bits, tmp_vlc_codes, entries)) {
              av_log(vc->avctx, AV_LOG_ERROR, " Invalid code lengths while generating vlcs. \n");
              ret = AVERROR_INVALIDDATA;
              goto error;
          }
          codebook_setup->maxdepth = 0;
          for (t = 0; t < entries; ++t)
              if (tmp_vlc_bits[t] >= codebook_setup->maxdepth)
                  codebook_setup->maxdepth = tmp_vlc_bits[t];
  
          if (codebook_setup->maxdepth > 3 * V_NB_BITS)
              codebook_setup->nb_bits = V_NB_BITS2;
          else
              codebook_setup->nb_bits = V_NB_BITS;
  
          codebook_setup->maxdepth = (codebook_setup->maxdepth+codebook_setup->nb_bits - 1) / codebook_setup->nb_bits;
  
          if ((ret = init_vlc(&codebook_setup->vlc, codebook_setup->nb_bits,
                              entries, tmp_vlc_bits, sizeof(*tmp_vlc_bits),
                              sizeof(*tmp_vlc_bits), tmp_vlc_codes,
                              sizeof(*tmp_vlc_codes), sizeof(*tmp_vlc_codes),
                              INIT_VLC_LE))) {
              av_log(vc->avctx, AV_LOG_ERROR, " Error generating vlc tables. \n");
              goto error;
          }
      }
  
      av_free(tmp_vlc_bits);
      av_free(tmp_vlc_codes);
      av_free(codebook_multiplicands);
      return 0;
  
  // Error:
  error:
      av_free(tmp_vlc_bits);
      av_free(tmp_vlc_codes);
      av_free(codebook_multiplicands);
      return ret;
  }
  
  // Process time domain transforms part (unused in Vorbis I)
  
  static int vorbis_parse_setup_hdr_tdtransforms(vorbis_context *vc)
  {
      GetBitContext *gb = &vc->gb;
      unsigned i, vorbis_time_count = get_bits(gb, 6) + 1;
  
      for (i = 0; i < vorbis_time_count; ++i) {
          unsigned vorbis_tdtransform = get_bits(gb, 16);
  
          av_dlog(NULL, " Vorbis time domain transform %u: %u\n",
                  vorbis_time_count, vorbis_tdtransform);
  
          if (vorbis_tdtransform) {
              av_log(vc->avctx, AV_LOG_ERROR, "Vorbis time domain transform data nonzero. \n");
              return AVERROR_INVALIDDATA;
          }
      }
      return 0;
  }
  
  // Process floors part
  
  static int vorbis_floor0_decode(vorbis_context *vc,
                                  vorbis_floor_data *vfu, float *vec);
  static int create_map(vorbis_context *vc, unsigned floor_number);
  static int vorbis_floor1_decode(vorbis_context *vc,
                                  vorbis_floor_data *vfu, float *vec);
  static int vorbis_parse_setup_hdr_floors(vorbis_context *vc)
  {
      GetBitContext *gb = &vc->gb;
      int i, j, k, ret;
  
      vc->floor_count = get_bits(gb, 6) + 1;
  
      vc->floors = av_mallocz(vc->floor_count * sizeof(*vc->floors));
      if (!vc->floors)
          return AVERROR(ENOMEM);
  
      for (i = 0; i < vc->floor_count; ++i) {
          vorbis_floor *floor_setup = &vc->floors[i];
  
          floor_setup->floor_type = get_bits(gb, 16);
  
          av_dlog(NULL, " %d. floor type %d \n", i, floor_setup->floor_type);
  
          if (floor_setup->floor_type == 1) {
              int maximum_class = -1;
              unsigned rangebits, rangemax, floor1_values = 2;
  
              floor_setup->decode = vorbis_floor1_decode;
  
              floor_setup->data.t1.partitions = get_bits(gb, 5);
  
              av_dlog(NULL, " %d.floor: %d partitions \n",
                      i, floor_setup->data.t1.partitions);
  
              for (j = 0; j < floor_setup->data.t1.partitions; ++j) {
                  floor_setup->data.t1.partition_class[j] = get_bits(gb, 4);
                  if (floor_setup->data.t1.partition_class[j] > maximum_class)
                      maximum_class = floor_setup->data.t1.partition_class[j];
  
                  av_dlog(NULL, " %d. floor %d partition class %d \n",
                          i, j, floor_setup->data.t1.partition_class[j]);
  
              }
  
              av_dlog(NULL, " maximum class %d \n", maximum_class);
  
              for (j = 0; j <= maximum_class; ++j) {
                  floor_setup->data.t1.class_dimensions[j] = get_bits(gb, 3) + 1;
                  floor_setup->data.t1.class_subclasses[j] = get_bits(gb, 2);
  
                  av_dlog(NULL, " %d floor %d class dim: %d subclasses %d \n", i, j,
                          floor_setup->data.t1.class_dimensions[j],
                          floor_setup->data.t1.class_subclasses[j]);
  
                  if (floor_setup->data.t1.class_subclasses[j]) {
                      GET_VALIDATED_INDEX(floor_setup->data.t1.class_masterbook[j], 8, vc->codebook_count)
  
                      av_dlog(NULL, "   masterbook: %d \n", floor_setup->data.t1.class_masterbook[j]);
                  }
  
                  for (k = 0; k < (1 << floor_setup->data.t1.class_subclasses[j]); ++k) {
                      int16_t bits = get_bits(gb, 8) - 1;
                      if (bits != -1)
                          VALIDATE_INDEX(bits, vc->codebook_count)
                      floor_setup->data.t1.subclass_books[j][k] = bits;
  
                      av_dlog(NULL, "    book %d. : %d \n", k, floor_setup->data.t1.subclass_books[j][k]);
                  }
              }
  
              floor_setup->data.t1.multiplier = get_bits(gb, 2) + 1;
              floor_setup->data.t1.x_list_dim = 2;
  
              for (j = 0; j < floor_setup->data.t1.partitions; ++j)
                  floor_setup->data.t1.x_list_dim+=floor_setup->data.t1.class_dimensions[floor_setup->data.t1.partition_class[j]];
  
              floor_setup->data.t1.list = av_mallocz_array(floor_setup->data.t1.x_list_dim,
                                                     sizeof(*floor_setup->data.t1.list));
              if (!floor_setup->data.t1.list)
                  return AVERROR(ENOMEM);
  
              rangebits = get_bits(gb, 4);
              rangemax = (1 << rangebits);
              if (rangemax > vc->blocksize[1] / 2) {
                  av_log(vc->avctx, AV_LOG_ERROR,
                         "Floor value is too large for blocksize: %u (%"PRIu32")\n",
                         rangemax, vc->blocksize[1] / 2);
                  return AVERROR_INVALIDDATA;
              }
              floor_setup->data.t1.list[0].x = 0;
              floor_setup->data.t1.list[1].x = rangemax;
  
              for (j = 0; j < floor_setup->data.t1.partitions; ++j) {
                  for (k = 0; k < floor_setup->data.t1.class_dimensions[floor_setup->data.t1.partition_class[j]]; ++k, ++floor1_values) {
                      floor_setup->data.t1.list[floor1_values].x = get_bits(gb, rangebits);
  
                      av_dlog(NULL, " %u. floor1 Y coord. %d\n", floor1_values,
                              floor_setup->data.t1.list[floor1_values].x);
                  }
              }
  
  // Precalculate order of x coordinates - needed for decode
              if (ff_vorbis_ready_floor1_list(vc->avctx,
                                              floor_setup->data.t1.list,
                                              floor_setup->data.t1.x_list_dim)) {
                  return AVERROR_INVALIDDATA;
              }
          } else if (floor_setup->floor_type == 0) {
              unsigned max_codebook_dim = 0;
  
              floor_setup->decode = vorbis_floor0_decode;
  
              floor_setup->data.t0.order          = get_bits(gb,  8);
              if (!floor_setup->data.t0.order) {
                  av_log(vc->avctx, AV_LOG_ERROR, "Floor 0 order is 0.\n");
                  return AVERROR_INVALIDDATA;
              }
              floor_setup->data.t0.rate           = get_bits(gb, 16);
              if (!floor_setup->data.t0.rate) {
                  av_log(vc->avctx, AV_LOG_ERROR, "Floor 0 rate is 0.\n");
                  return AVERROR_INVALIDDATA;
              }
              floor_setup->data.t0.bark_map_size  = get_bits(gb, 16);
              if (!floor_setup->data.t0.bark_map_size) {
                  av_log(vc->avctx, AV_LOG_ERROR,
                         "Floor 0 bark map size is 0.\n");
                  return AVERROR_INVALIDDATA;
              }
              floor_setup->data.t0.amplitude_bits = get_bits(gb,  6);
              floor_setup->data.t0.amplitude_offset = get_bits(gb, 8);
              floor_setup->data.t0.num_books        = get_bits(gb, 4) + 1;
  
              /* allocate mem for booklist */
              floor_setup->data.t0.book_list =
                  av_malloc(floor_setup->data.t0.num_books);
              if (!floor_setup->data.t0.book_list)
                  return AVERROR(ENOMEM);
              /* read book indexes */
              {
                  int idx;
                  unsigned book_idx;
                  for (idx = 0; idx < floor_setup->data.t0.num_books; ++idx) {
                      GET_VALIDATED_INDEX(book_idx, 8, vc->codebook_count)
                      floor_setup->data.t0.book_list[idx] = book_idx;
                      if (vc->codebooks[book_idx].dimensions > max_codebook_dim)
                          max_codebook_dim = vc->codebooks[book_idx].dimensions;
                  }
              }
  
              if ((ret = create_map(vc, i)) < 0)
                  return ret;
  
              /* codebook dim is for padding if codebook dim doesn't *
               * divide order+1 then we need to read more data       */
              floor_setup->data.t0.lsp =
                  av_malloc_array((floor_setup->data.t0.order + 1 + max_codebook_dim),
                                  sizeof(*floor_setup->data.t0.lsp));
              if (!floor_setup->data.t0.lsp)
                  return AVERROR(ENOMEM);
  
              /* debug output parsed headers */
              av_dlog(NULL, "floor0 order: %u\n", floor_setup->data.t0.order);
              av_dlog(NULL, "floor0 rate: %u\n", floor_setup->data.t0.rate);
              av_dlog(NULL, "floor0 bark map size: %u\n",
                      floor_setup->data.t0.bark_map_size);
              av_dlog(NULL, "floor0 amplitude bits: %u\n",
                      floor_setup->data.t0.amplitude_bits);
              av_dlog(NULL, "floor0 amplitude offset: %u\n",
                      floor_setup->data.t0.amplitude_offset);
              av_dlog(NULL, "floor0 number of books: %u\n",
                      floor_setup->data.t0.num_books);
              av_dlog(NULL, "floor0 book list pointer: %p\n",
                      floor_setup->data.t0.book_list);
              {
                  int idx;
                  for (idx = 0; idx < floor_setup->data.t0.num_books; ++idx) {
                      av_dlog(NULL, "  Book %d: %u\n", idx + 1,
                              floor_setup->data.t0.book_list[idx]);
                  }
              }
          } else {
              av_log(vc->avctx, AV_LOG_ERROR, "Invalid floor type!\n");
              return AVERROR_INVALIDDATA;
          }
      }
      return 0;
  }
  
  // Process residues part
  
  static int vorbis_parse_setup_hdr_residues(vorbis_context *vc)
  {
      GetBitContext *gb = &vc->gb;
      unsigned i, j, k;
  
      vc->residue_count = get_bits(gb, 6)+1;
      vc->residues      = av_mallocz(vc->residue_count * sizeof(*vc->residues));
      if (!vc->residues)
          return AVERROR(ENOMEM);
  
      av_dlog(NULL, " There are %d residues. \n", vc->residue_count);
  
      for (i = 0; i < vc->residue_count; ++i) {
          vorbis_residue *res_setup = &vc->residues[i];
          uint8_t cascade[64];
          unsigned high_bits, low_bits;
  
          res_setup->type = get_bits(gb, 16);
  
          av_dlog(NULL, " %u. residue type %d\n", i, res_setup->type);
  
          res_setup->begin          = get_bits(gb, 24);
          res_setup->end            = get_bits(gb, 24);
          res_setup->partition_size = get_bits(gb, 24) + 1;
          /* Validations to prevent a buffer overflow later. */
          if (res_setup->begin>res_setup->end ||
              (res_setup->end-res_setup->begin) / res_setup->partition_size > FFMIN(V_MAX_PARTITIONS, 65535)) {
              av_log(vc->avctx, AV_LOG_ERROR,
                     "partition out of bounds: type, begin, end, size, blocksize: %"PRIu16", %"PRIu32", %"PRIu32", %u, %"PRIu32"\n",
                     res_setup->type, res_setup->begin, res_setup->end,
                     res_setup->partition_size, vc->blocksize[1] / 2);
              return AVERROR_INVALIDDATA;
          }
  
          res_setup->classifications = get_bits(gb, 6) + 1;
          GET_VALIDATED_INDEX(res_setup->classbook, 8, vc->codebook_count)
  
          res_setup->ptns_to_read =
              (res_setup->end - res_setup->begin) / res_setup->partition_size;
          res_setup->classifs = av_malloc_array(res_setup->ptns_to_read,
                                          vc->audio_channels *
                                          sizeof(*res_setup->classifs));
          if (!res_setup->classifs)
              return AVERROR(ENOMEM);
  
          av_dlog(NULL, "    begin %d end %d part.size %d classif.s %d classbook %d \n",
                  res_setup->begin, res_setup->end, res_setup->partition_size,
                  res_setup->classifications, res_setup->classbook);
  
          for (j = 0; j < res_setup->classifications; ++j) {
              high_bits = 0;
              low_bits  = get_bits(gb, 3);
              if (get_bits1(gb))
                  high_bits = get_bits(gb, 5);
              cascade[j] = (high_bits << 3) + low_bits;
  
              av_dlog(NULL, "     %u class cascade depth: %d\n", j, ilog(cascade[j]));
          }
  
          res_setup->maxpass = 0;
          for (j = 0; j < res_setup->classifications; ++j) {
              for (k = 0; k < 8; ++k) {
                  if (cascade[j]&(1 << k)) {
                      GET_VALIDATED_INDEX(res_setup->books[j][k], 8, vc->codebook_count)
  
                      av_dlog(NULL, "     %u class cascade depth %u book: %d\n",
                              j, k, res_setup->books[j][k]);
  
                      if (k>res_setup->maxpass)
                          res_setup->maxpass = k;
                  } else {
                      res_setup->books[j][k] = -1;
                  }
              }
          }
      }
      return 0;
  }
  
  // Process mappings part
  
  static int vorbis_parse_setup_hdr_mappings(vorbis_context *vc)
  {
      GetBitContext *gb = &vc->gb;
      unsigned i, j;
  
      vc->mapping_count = get_bits(gb, 6)+1;
      vc->mappings      = av_mallocz(vc->mapping_count * sizeof(*vc->mappings));
      if (!vc->mappings)
          return AVERROR(ENOMEM);
  
      av_dlog(NULL, " There are %d mappings. \n", vc->mapping_count);
  
      for (i = 0; i < vc->mapping_count; ++i) {
          vorbis_mapping *mapping_setup = &vc->mappings[i];
  
          if (get_bits(gb, 16)) {
              av_log(vc->avctx, AV_LOG_ERROR, "Other mappings than type 0 are not compliant with the Vorbis I specification. \n");
              return AVERROR_INVALIDDATA;
          }
          if (get_bits1(gb)) {
              mapping_setup->submaps = get_bits(gb, 4) + 1;
          } else {
              mapping_setup->submaps = 1;
          }
  
          if (get_bits1(gb)) {
              mapping_setup->coupling_steps = get_bits(gb, 8) + 1;
              mapping_setup->magnitude      = av_mallocz(mapping_setup->coupling_steps *
                                                         sizeof(*mapping_setup->magnitude));
              mapping_setup->angle          = av_mallocz(mapping_setup->coupling_steps *
                                                         sizeof(*mapping_setup->angle));
              if (!mapping_setup->angle || !mapping_setup->magnitude)
                  return AVERROR(ENOMEM);
  
              for (j = 0; j < mapping_setup->coupling_steps; ++j) {
                  GET_VALIDATED_INDEX(mapping_setup->magnitude[j], ilog(vc->audio_channels - 1), vc->audio_channels)
                  GET_VALIDATED_INDEX(mapping_setup->angle[j],     ilog(vc->audio_channels - 1), vc->audio_channels)
              }
          } else {
              mapping_setup->coupling_steps = 0;
          }
  
          av_dlog(NULL, "   %u mapping coupling steps: %d\n",
                  i, mapping_setup->coupling_steps);
  
          if (get_bits(gb, 2)) {
              av_log(vc->avctx, AV_LOG_ERROR, "%u. mapping setup data invalid.\n", i);
              return AVERROR_INVALIDDATA; // following spec.
          }
  
          if (mapping_setup->submaps>1) {
              mapping_setup->mux = av_mallocz_array(vc->audio_channels,
                                              sizeof(*mapping_setup->mux));
              if (!mapping_setup->mux)
                  return AVERROR(ENOMEM);
  
              for (j = 0; j < vc->audio_channels; ++j)
                  mapping_setup->mux[j] = get_bits(gb, 4);
          }
  
          for (j = 0; j < mapping_setup->submaps; ++j) {
              skip_bits(gb, 8); // FIXME check?
              GET_VALIDATED_INDEX(mapping_setup->submap_floor[j],   8, vc->floor_count)
              GET_VALIDATED_INDEX(mapping_setup->submap_residue[j], 8, vc->residue_count)
  
              av_dlog(NULL, "   %u mapping %u submap : floor %d, residue %d\n", i, j,
                      mapping_setup->submap_floor[j],
                      mapping_setup->submap_residue[j]);
          }
      }
      return 0;
  }
  
  // Process modes part
  
  static int create_map(vorbis_context *vc, unsigned floor_number)
  {
      vorbis_floor *floors = vc->floors;
      vorbis_floor0 *vf;
      int idx;
      int blockflag, n;
      int32_t *map;
  
      for (blockflag = 0; blockflag < 2; ++blockflag) {
          n = vc->blocksize[blockflag] / 2;
          floors[floor_number].data.t0.map[blockflag] =
              av_malloc_array(n + 1, sizeof(int32_t)); // n + sentinel
          if (!floors[floor_number].data.t0.map[blockflag])
              return AVERROR(ENOMEM);
  
          map =  floors[floor_number].data.t0.map[blockflag];
          vf  = &floors[floor_number].data.t0;
  
          for (idx = 0; idx < n; ++idx) {
              map[idx] = floor(BARK((vf->rate * idx) / (2.0f * n)) *
                               (vf->bark_map_size / BARK(vf->rate / 2.0f)));
              if (vf->bark_map_size-1 < map[idx])
                  map[idx] = vf->bark_map_size - 1;
          }
          map[n] = -1;
          vf->map_size[blockflag] = n;
      }
  
      for (idx = 0; idx <= n; ++idx) {
          av_dlog(NULL, "floor0 map: map at pos %d is %d\n", idx, map[idx]);
      }
  
      return 0;
  }
  
  static int vorbis_parse_setup_hdr_modes(vorbis_context *vc)
  {
      GetBitContext *gb = &vc->gb;
      unsigned i;
  
      vc->mode_count = get_bits(gb, 6) + 1;
      vc->modes      = av_mallocz(vc->mode_count * sizeof(*vc->modes));
      if (!vc->modes)
          return AVERROR(ENOMEM);
  
      av_dlog(NULL, " There are %d modes.\n", vc->mode_count);
  
      for (i = 0; i < vc->mode_count; ++i) {
          vorbis_mode *mode_setup = &vc->modes[i];
  
          mode_setup->blockflag     = get_bits1(gb);
          mode_setup->windowtype    = get_bits(gb, 16); //FIXME check
          mode_setup->transformtype = get_bits(gb, 16); //FIXME check
          GET_VALIDATED_INDEX(mode_setup->mapping, 8, vc->mapping_count);
  
          av_dlog(NULL, " %u mode: blockflag %d, windowtype %d, transformtype %d, mapping %d\n",
                  i, mode_setup->blockflag, mode_setup->windowtype,
                  mode_setup->transformtype, mode_setup->mapping);
      }
      return 0;
  }
  
  // Process the whole setup header using the functions above
  
  static int vorbis_parse_setup_hdr(vorbis_context *vc)
  {
      GetBitContext *gb = &vc->gb;
      int ret;
  
      if ((get_bits(gb, 8) != 'v') || (get_bits(gb, 8) != 'o') ||
          (get_bits(gb, 8) != 'r') || (get_bits(gb, 8) != 'b') ||
          (get_bits(gb, 8) != 'i') || (get_bits(gb, 8) != 's')) {
          av_log(vc->avctx, AV_LOG_ERROR, " Vorbis setup header packet corrupt (no vorbis signature). \n");
          return AVERROR_INVALIDDATA;
      }
  
      if ((ret = vorbis_parse_setup_hdr_codebooks(vc))) {
          av_log(vc->avctx, AV_LOG_ERROR, " Vorbis setup header packet corrupt (codebooks). \n");
          return ret;
      }
      if ((ret = vorbis_parse_setup_hdr_tdtransforms(vc))) {
          av_log(vc->avctx, AV_LOG_ERROR, " Vorbis setup header packet corrupt (time domain transforms). \n");
          return ret;
      }
      if ((ret = vorbis_parse_setup_hdr_floors(vc))) {
          av_log(vc->avctx, AV_LOG_ERROR, " Vorbis setup header packet corrupt (floors). \n");
          return ret;
      }
      if ((ret = vorbis_parse_setup_hdr_residues(vc))) {
          av_log(vc->avctx, AV_LOG_ERROR, " Vorbis setup header packet corrupt (residues). \n");
          return ret;
      }
      if ((ret = vorbis_parse_setup_hdr_mappings(vc))) {
          av_log(vc->avctx, AV_LOG_ERROR, " Vorbis setup header packet corrupt (mappings). \n");
          return ret;
      }
      if ((ret = vorbis_parse_setup_hdr_modes(vc))) {
          av_log(vc->avctx, AV_LOG_ERROR, " Vorbis setup header packet corrupt (modes). \n");
          return ret;
      }
      if (!get_bits1(gb)) {
          av_log(vc->avctx, AV_LOG_ERROR, " Vorbis setup header packet corrupt (framing flag). \n");
          return AVERROR_INVALIDDATA; // framing flag bit unset error
      }
  
      return 0;
  }
  
  // Process the identification header
  
  static int vorbis_parse_id_hdr(vorbis_context *vc)
  {
      GetBitContext *gb = &vc->gb;
      unsigned bl0, bl1;
  
      if ((get_bits(gb, 8) != 'v') || (get_bits(gb, 8) != 'o') ||
          (get_bits(gb, 8) != 'r') || (get_bits(gb, 8) != 'b') ||
          (get_bits(gb, 8) != 'i') || (get_bits(gb, 8) != 's')) {
          av_log(vc->avctx, AV_LOG_ERROR, " Vorbis id header packet corrupt (no vorbis signature). \n");
          return AVERROR_INVALIDDATA;
      }
  
      vc->version        = get_bits_long(gb, 32);    //FIXME check 0
      vc->audio_channels = get_bits(gb, 8);
      if (vc->audio_channels <= 0) {
          av_log(vc->avctx, AV_LOG_ERROR, "Invalid number of channels\n");
          return AVERROR_INVALIDDATA;
      }
      vc->audio_samplerate = get_bits_long(gb, 32);
      if (vc->audio_samplerate <= 0) {
          av_log(vc->avctx, AV_LOG_ERROR, "Invalid samplerate\n");
          return AVERROR_INVALIDDATA;
      }
      vc->bitrate_maximum = get_bits_long(gb, 32);
      vc->bitrate_nominal = get_bits_long(gb, 32);
      vc->bitrate_minimum = get_bits_long(gb, 32);
      bl0 = get_bits(gb, 4);
      bl1 = get_bits(gb, 4);
      if (bl0 > 13 || bl0 < 6 || bl1 > 13 || bl1 < 6 || bl1 < bl0) {
          av_log(vc->avctx, AV_LOG_ERROR, " Vorbis id header packet corrupt (illegal blocksize). \n");
          return AVERROR_INVALIDDATA;
      }
      vc->blocksize[0] = (1 << bl0);
      vc->blocksize[1] = (1 << bl1);
      vc->win[0] = ff_vorbis_vwin[bl0 - 6];
      vc->win[1] = ff_vorbis_vwin[bl1 - 6];
  
      if ((get_bits1(gb)) == 0) {
          av_log(vc->avctx, AV_LOG_ERROR, " Vorbis id header packet corrupt (framing flag not set). \n");
          return AVERROR_INVALIDDATA;
      }
  
      vc->channel_residues =  av_malloc_array(vc->blocksize[1]  / 2, vc->audio_channels * sizeof(*vc->channel_residues));
      vc->saved            =  av_mallocz_array(vc->blocksize[1] / 4, vc->audio_channels * sizeof(*vc->saved));
      if (!vc->channel_residues || !vc->saved)
          return AVERROR(ENOMEM);
  
      vc->previous_window  = -1;
  
      ff_mdct_init(&vc->mdct[0], bl0, 1, -1.0);
      ff_mdct_init(&vc->mdct[1], bl1, 1, -1.0);
  
      av_dlog(NULL, " vorbis version %d \n audio_channels %d \n audio_samplerate %d \n bitrate_max %d \n bitrate_nom %d \n bitrate_min %d \n blk_0 %d blk_1 %d \n ",
              vc->version, vc->audio_channels, vc->audio_samplerate, vc->bitrate_maximum, vc->bitrate_nominal, vc->bitrate_minimum, vc->blocksize[0], vc->blocksize[1]);
  
  /*
      BLK = vc->blocksize[0];
      for (i = 0; i < BLK / 2; ++i) {
          vc->win[0][i] = sin(0.5*3.14159265358*(sin(((float)i + 0.5) / (float)BLK*3.14159265358))*(sin(((float)i + 0.5) / (float)BLK*3.14159265358)));
      }
  */
  
      return 0;
  }
  
  // Process the extradata using the functions above (identification header, setup header)
  
  static av_cold int vorbis_decode_init(AVCodecContext *avctx)
  {
      vorbis_context *vc = avctx->priv_data;
      uint8_t *headers   = avctx->extradata;
      int headers_len    = avctx->extradata_size;
      uint8_t *header_start[3];
      int header_len[3];
      GetBitContext *gb = &vc->gb;
      int hdr_type, ret;
  
      vc->avctx = avctx;
      ff_vorbisdsp_init(&vc->dsp);
      avpriv_float_dsp_init(&vc->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
      ff_fmt_convert_init(&vc->fmt_conv, avctx);
  
      avctx->sample_fmt = AV_SAMPLE_FMT_FLTP;
  
      if (!headers_len) {
          av_log(avctx, AV_LOG_ERROR, "Extradata missing.\n");
          return AVERROR_INVALIDDATA;
      }
  
      if ((ret = avpriv_split_xiph_headers(headers, headers_len, 30, header_start, header_len)) < 0) {
          av_log(avctx, AV_LOG_ERROR, "Extradata corrupt.\n");
          return ret;
      }
  
      init_get_bits(gb, header_start[0], header_len[0]*8);
      hdr_type = get_bits(gb, 8);
      if (hdr_type != 1) {
          av_log(avctx, AV_LOG_ERROR, "First header is not the id header.\n");
          return AVERROR_INVALIDDATA;
      }
      if ((ret = vorbis_parse_id_hdr(vc))) {
          av_log(avctx, AV_LOG_ERROR, "Id header corrupt.\n");
          vorbis_free(vc);
          return ret;
      }
  
      init_get_bits(gb, header_start[2], header_len[2]*8);
      hdr_type = get_bits(gb, 8);
      if (hdr_type != 5) {
          av_log(avctx, AV_LOG_ERROR, "Third header is not the setup header.\n");
          vorbis_free(vc);
          return AVERROR_INVALIDDATA;
      }
      if ((ret = vorbis_parse_setup_hdr(vc))) {
          av_log(avctx, AV_LOG_ERROR, "Setup header corrupt.\n");
          vorbis_free(vc);
          return ret;
      }
  
      if (vc->audio_channels > 8)
          avctx->channel_layout = 0;
      else
          avctx->channel_layout = ff_vorbis_channel_layouts[vc->audio_channels - 1];
  
      avctx->channels    = vc->audio_channels;
      avctx->sample_rate = vc->audio_samplerate;
  
      return 0;
  }
  
  // Decode audiopackets -------------------------------------------------
  
  // Read and decode floor
  
  static int vorbis_floor0_decode(vorbis_context *vc,
                                  vorbis_floor_data *vfu, float *vec)
  {
      vorbis_floor0 *vf = &vfu->t0;
      float *lsp = vf->lsp;
      unsigned amplitude, book_idx;
      unsigned blockflag = vc->modes[vc->mode_number].blockflag;
  
      if (!vf->amplitude_bits)
          return 1;
  
      amplitude = get_bits(&vc->gb, vf->amplitude_bits);
      if (amplitude > 0) {
          float last = 0;
          unsigned idx, lsp_len = 0;
          vorbis_codebook codebook;
  
          book_idx = get_bits(&vc->gb, ilog(vf->num_books));
          if (book_idx >= vf->num_books) {
              av_log(vc->avctx, AV_LOG_ERROR, "floor0 dec: booknumber too high!\n");
              book_idx =  0;
          }
          av_dlog(NULL, "floor0 dec: booknumber: %u\n", book_idx);
          codebook = vc->codebooks[vf->book_list[book_idx]];
          /* Invalid codebook! */
          if (!codebook.codevectors)
              return AVERROR_INVALIDDATA;
  
          while (lsp_len<vf->order) {
              int vec_off;
  
              av_dlog(NULL, "floor0 dec: book dimension: %d\n", codebook.dimensions);
              av_dlog(NULL, "floor0 dec: maximum depth: %d\n", codebook.maxdepth);
              /* read temp vector */
              vec_off = get_vlc2(&vc->gb, codebook.vlc.table,
                                 codebook.nb_bits, codebook.maxdepth)
                        * codebook.dimensions;
              av_dlog(NULL, "floor0 dec: vector offset: %d\n", vec_off);
              /* copy each vector component and add last to it */
              for (idx = 0; idx < codebook.dimensions; ++idx)
                  lsp[lsp_len+idx] = codebook.codevectors[vec_off+idx] + last;
              last = lsp[lsp_len+idx-1]; /* set last to last vector component */
  
              lsp_len += codebook.dimensions;
          }
          /* DEBUG: output lsp coeffs */
          {
              int idx;
              for (idx = 0; idx < lsp_len; ++idx)
                  av_dlog(NULL, "floor0 dec: coeff at %d is %f\n", idx, lsp[idx]);
          }
  
          /* synthesize floor output vector */
          {
              int i;
              int order = vf->order;
              float wstep = M_PI / vf->bark_map_size;
  
              for (i = 0; i < order; i++)
                  lsp[i] = 2.0f * cos(lsp[i]);
  
              av_dlog(NULL, "floor0 synth: map_size = %"PRIu32"; m = %d; wstep = %f\n",
                      vf->map_size[blockflag], order, wstep);
  
              i = 0;
              while (i < vf->map_size[blockflag]) {
                  int j, iter_cond = vf->map[blockflag][i];
                  float p = 0.5f;
                  float q = 0.5f;
                  float two_cos_w = 2.0f * cos(wstep * iter_cond); // needed all times
  
                  /* similar part for the q and p products */
                  for (j = 0; j + 1 < order; j += 2) {
                      q *= lsp[j]     - two_cos_w;
                      p *= lsp[j + 1] - two_cos_w;
                  }
                  if (j == order) { // even order
                      p *= p * (2.0f - two_cos_w);
                      q *= q * (2.0f + two_cos_w);
                  } else { // odd order
                      q *= two_cos_w-lsp[j]; // one more time for q
  
                      /* final step and square */
                      p *= p * (4.f - two_cos_w * two_cos_w);
                      q *= q;
                  }
  
                  /* calculate linear floor value */
                  q = exp((((amplitude*vf->amplitude_offset) /
                            (((1 << vf->amplitude_bits) - 1) * sqrt(p + q)))
                           - vf->amplitude_offset) * .11512925f);
  
                  /* fill vector */
                  do {
                      vec[i] = q; ++i;
                  } while (vf->map[blockflag][i] == iter_cond);
              }
          }
      } else {
          /* this channel is unused */
          return 1;
      }
  
      av_dlog(NULL, " Floor0 decoded\n");
  
      return 0;
  }
  
  static int vorbis_floor1_decode(vorbis_context *vc,
                                  vorbis_floor_data *vfu, float *vec)
  {
      vorbis_floor1 *vf = &vfu->t1;
      GetBitContext *gb = &vc->gb;
      uint16_t range_v[4] = { 256, 128, 86, 64 };
      unsigned range = range_v[vf->multiplier - 1];
      uint16_t floor1_Y[258];
      uint16_t floor1_Y_final[258];
      int floor1_flag[258];
      unsigned partition_class, cdim, cbits, csub, cval, offset, i, j;
      int book, adx, ady, dy, off, predicted, err;
  
  
      if (!get_bits1(gb)) // silence
          return 1;
  
  // Read values (or differences) for the floor's points
  
      floor1_Y[0] = get_bits(gb, ilog(range - 1));
      floor1_Y[1] = get_bits(gb, ilog(range - 1));
  
      av_dlog(NULL, "floor 0 Y %d floor 1 Y %d \n", floor1_Y[0], floor1_Y[1]);
  
      offset = 2;
      for (i = 0; i < vf->partitions; ++i) {
          partition_class = vf->partition_class[i];
          cdim   = vf->class_dimensions[partition_class];
          cbits  = vf->class_subclasses[partition_class];
          csub = (1 << cbits) - 1;
          cval = 0;
  
          av_dlog(NULL, "Cbits %u\n", cbits);
  
          if (cbits) // this reads all subclasses for this partition's class
              cval = get_vlc2(gb, vc->codebooks[vf->class_masterbook[partition_class]].vlc.table,
                              vc->codebooks[vf->class_masterbook[partition_class]].nb_bits, 3);
  
          for (j = 0; j < cdim; ++j) {
              book = vf->subclass_books[partition_class][cval & csub];
  
              av_dlog(NULL, "book %d Cbits %u cval %u  bits:%d\n",
                      book, cbits, cval, get_bits_count(gb));
  
              cval = cval >> cbits;
              if (book > -1) {
                  int v = get_vlc2(gb, vc->codebooks[book].vlc.table,
                                   vc->codebooks[book].nb_bits, 3);
                  if (v < 0)
                      return AVERROR_INVALIDDATA;
                  floor1_Y[offset+j] = v;
              } else {
                  floor1_Y[offset+j] = 0;
              }
  
              av_dlog(NULL, " floor(%d) = %d \n",
                      vf->list[offset+j].x, floor1_Y[offset+j]);
          }
          offset+=cdim;
      }
  
  // Amplitude calculation from the differences
  
      floor1_flag[0] = 1;
      floor1_flag[1] = 1;
      floor1_Y_final[0] = floor1_Y[0];
      floor1_Y_final[1] = floor1_Y[1];
  
      for (i = 2; i < vf->x_list_dim; ++i) {
          unsigned val, highroom, lowroom, room, high_neigh_offs, low_neigh_offs;
  
          low_neigh_offs  = vf->list[i].low;
          high_neigh_offs = vf->list[i].high;
          dy  = floor1_Y_final[high_neigh_offs] - floor1_Y_final[low_neigh_offs];  // render_point begin
          adx = vf->list[high_neigh_offs].x - vf->list[low_neigh_offs].x;
          ady = FFABS(dy);
          err = ady * (vf->list[i].x - vf->list[low_neigh_offs].x);
          off = err / adx;
          if (dy < 0) {
              predicted = floor1_Y_final[low_neigh_offs] - off;
          } else {
              predicted = floor1_Y_final[low_neigh_offs] + off;
          } // render_point end
  
          val = floor1_Y[i];
          highroom = range-predicted;
          lowroom  = predicted;
          if (highroom < lowroom) {
              room = highroom * 2;
          } else {
              room = lowroom * 2;   // SPEC misspelling
          }
          if (val) {
              floor1_flag[low_neigh_offs]  = 1;
              floor1_flag[high_neigh_offs] = 1;
              floor1_flag[i]               = 1;
              if (val >= room) {
                  if (highroom > lowroom) {
                      floor1_Y_final[i] = av_clip_uint16(val - lowroom + predicted);
                  } else {
                      floor1_Y_final[i] = av_clip_uint16(predicted - val + highroom - 1);
                  }
              } else {
                  if (val & 1) {
                      floor1_Y_final[i] = av_clip_uint16(predicted - (val + 1) / 2);
                  } else {
                      floor1_Y_final[i] = av_clip_uint16(predicted + val / 2);
                  }
              }
          } else {
              floor1_flag[i]    = 0;
              floor1_Y_final[i] = av_clip_uint16(predicted);
          }
  
          av_dlog(NULL, " Decoded floor(%d) = %u / val %u\n",
                  vf->list[i].x, floor1_Y_final[i], val);
      }
  
  // Curve synth - connect the calculated dots and convert from dB scale FIXME optimize ?
  
      ff_vorbis_floor1_render_list(vf->list, vf->x_list_dim, floor1_Y_final, floor1_flag, vf->multiplier, vec, vf->list[1].x);
  
      av_dlog(NULL, " Floor decoded\n");
  
      return 0;
  }
  
  static av_always_inline int setup_classifs(vorbis_context *vc,
                                             vorbis_residue *vr,
                                             uint8_t *do_not_decode,
                                             unsigned ch_used,
                                             int partition_count,
                                             int ptns_to_read
                                            )
  {
      int p, j, i;
      unsigned c_p_c         = vc->codebooks[vr->classbook].dimensions;
      unsigned inverse_class = ff_inverse[vr->classifications];
      unsigned temp, temp2;
      for (p = 0, j = 0; j < ch_used; ++j) {
          if (!do_not_decode[j]) {
              temp = get_vlc2(&vc->gb, vc->codebooks[vr->classbook].vlc.table,
                                       vc->codebooks[vr->classbook].nb_bits, 3);
  
              av_dlog(NULL, "Classword: %u\n", temp);
  
              if ((int)temp < 0)
                  return temp;
  
              av_assert0(vr->classifications > 1); //needed for inverse[]
  
              if (temp <= 65536) {
                  for (i = partition_count + c_p_c - 1; i >= partition_count; i--) {
                      temp2 = (((uint64_t)temp) * inverse_class) >> 32;
  
                      if (i < ptns_to_read)
                          vr->classifs[p + i] = temp - temp2 * vr->classifications;
                      temp = temp2;
                  }
              } else {
                  for (i = partition_count + c_p_c - 1; i >= partition_count; i--) {
                      temp2 = temp / vr->classifications;
  
                      if (i < ptns_to_read)
                          vr->classifs[p + i] = temp - temp2 * vr->classifications;
                      temp = temp2;
                  }
              }
          }
          p += ptns_to_read;
      }
      return 0;
  }
  // Read and decode residue
  
  static av_always_inline int vorbis_residue_decode_internal(vorbis_context *vc,
                                                             vorbis_residue *vr,
                                                             unsigned ch,
                                                             uint8_t *do_not_decode,
                                                             float *vec,
                                                             unsigned vlen,
                                                             unsigned ch_left,
                                                             int vr_type)
  {
      GetBitContext *gb = &vc->gb;
      unsigned c_p_c        = vc->codebooks[vr->classbook].dimensions;
      uint8_t *classifs = vr->classifs;
      unsigned pass, ch_used, i, j, k, l;
      unsigned max_output = (ch - 1) * vlen;
      int ptns_to_read = vr->ptns_to_read;
      int libvorbis_bug = 0;
  
      if (vr_type == 2) {
          for (j = 1; j < ch; ++j)
              do_not_decode[0] &= do_not_decode[j];  // FIXME - clobbering input
          if (do_not_decode[0])
              return 0;
          ch_used = 1;
          max_output += vr->end / ch;
      } else {
          ch_used = ch;
          max_output += vr->end;
      }
  
      if (max_output > ch_left * vlen) {
          if (max_output <= ch_left * vlen + vr->partition_size*ch_used/ch) {
              ptns_to_read--;
              libvorbis_bug = 1;
          } else {
              av_log(vc->avctx, AV_LOG_ERROR, "Insufficient output buffer\n");
              return AVERROR_INVALIDDATA;
          }
      }
  
      av_dlog(NULL, " residue type 0/1/2 decode begin, ch: %d  cpc %d  \n", ch, c_p_c);
  
      for (pass = 0; pass <= vr->maxpass; ++pass) { // FIXME OPTIMIZE?
          int voffset, partition_count, j_times_ptns_to_read;
  
          voffset = vr->begin;
          for (partition_count = 0; partition_count < ptns_to_read;) {  // SPEC        error
              if (!pass) {
                  int ret;
                  if ((ret = setup_classifs(vc, vr, do_not_decode, ch_used, partition_count, ptns_to_read)) < 0)
                      return ret;
              }
              for (i = 0; (i < c_p_c) && (partition_count < ptns_to_read); ++i) {
                  for (j_times_ptns_to_read = 0, j = 0; j < ch_used; ++j) {
                      unsigned voffs;
  
                      if (!do_not_decode[j]) {
                          unsigned vqclass = classifs[j_times_ptns_to_read + partition_count];
                          int vqbook  = vr->books[vqclass][pass];
  
                          if (vqbook >= 0 && vc->codebooks[vqbook].codevectors) {
                              unsigned coffs;
                              unsigned dim  = vc->codebooks[vqbook].dimensions;
                              unsigned step = FASTDIV(vr->partition_size << 1, dim << 1);
                              vorbis_codebook codebook = vc->codebooks[vqbook];
  
                              if (vr_type == 0) {
  
                                  voffs = voffset+j*vlen;
                                  for (k = 0; k < step; ++k) {
                                      coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;
                                      for (l = 0; l < dim; ++l)
                                          vec[voffs + k + l * step] += codebook.codevectors[coffs + l];
                                  }
                              } else if (vr_type == 1) {
                                  voffs = voffset + j * vlen;
                                  for (k = 0; k < step; ++k) {
                                      coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;
                                      for (l = 0; l < dim; ++l, ++voffs) {
                                          vec[voffs]+=codebook.codevectors[coffs+l];
  
                                          av_dlog(NULL, " pass %d offs: %d curr: %f change: %f cv offs.: %d  \n",
                                                  pass, voffs, vec[voffs], codebook.codevectors[coffs+l], coffs);
                                      }
                                  }
                              } else if (vr_type == 2 && ch == 2 && (voffset & 1) == 0 && (dim & 1) == 0) { // most frequent case optimized
                                  voffs = voffset >> 1;
  
                                  if (dim == 2) {
                                      for (k = 0; k < step; ++k) {
                                          coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * 2;
                                          vec[voffs + k       ] += codebook.codevectors[coffs    ];
                                          vec[voffs + k + vlen] += codebook.codevectors[coffs + 1];
                                      }
                                  } else if (dim == 4) {
                                      for (k = 0; k < step; ++k, voffs += 2) {
                                          coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * 4;
                                          vec[voffs           ] += codebook.codevectors[coffs    ];
                                          vec[voffs + 1       ] += codebook.codevectors[coffs + 2];
                                          vec[voffs + vlen    ] += codebook.codevectors[coffs + 1];
                                          vec[voffs + vlen + 1] += codebook.codevectors[coffs + 3];
                                      }
                                  } else
                                  for (k = 0; k < step; ++k) {
                                      coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;
                                      for (l = 0; l < dim; l += 2, voffs++) {
                                          vec[voffs       ] += codebook.codevectors[coffs + l    ];
                                          vec[voffs + vlen] += codebook.codevectors[coffs + l + 1];
  
                                          av_dlog(NULL, " pass %d offs: %d curr: %f change: %f cv offs.: %d+%d  \n",
                                                  pass, voffset / ch + (voffs % ch) * vlen,
                                                  vec[voffset / ch + (voffs % ch) * vlen],
                                                  codebook.codevectors[coffs + l], coffs, l);
                                      }
                                  }
  
                              } else if (vr_type == 2) {
                                  unsigned voffs_div = FASTDIV(voffset << 1, ch <<1);
                                  unsigned voffs_mod = voffset - voffs_div * ch;
  
                                  for (k = 0; k < step; ++k) {
                                      coffs = get_vlc2(gb, codebook.vlc.table, codebook.nb_bits, 3) * dim;
                                      for (l = 0; l < dim; ++l) {
                                          vec[voffs_div + voffs_mod * vlen] +=
                                              codebook.codevectors[coffs + l];
  
                                          av_dlog(NULL, " pass %d offs: %d curr: %f change: %f cv offs.: %d+%d  \n",
                                                  pass, voffs_div + voffs_mod * vlen,
                                                  vec[voffs_div + voffs_mod * vlen],
                                                  codebook.codevectors[coffs + l], coffs, l);
  
                                          if (++voffs_mod == ch) {
                                              voffs_div++;
                                              voffs_mod = 0;
                                          }
                                      }
                                  }
                              }
                          }
                      }
                      j_times_ptns_to_read += ptns_to_read;
                  }
                  ++partition_count;
                  voffset += vr->partition_size;
              }
          }
          if (libvorbis_bug && !pass) {
              for (j = 0; j < ch_used; ++j) {
                  if (!do_not_decode[j]) {
                      get_vlc2(&vc->gb, vc->codebooks[vr->classbook].vlc.table,
                                  vc->codebooks[vr->classbook].nb_bits, 3);
                  }
              }
          }
      }
      return 0;
  }
  
  static inline int vorbis_residue_decode(vorbis_context *vc, vorbis_residue *vr,
                                          unsigned ch,
                                          uint8_t *do_not_decode,
                                          float *vec, unsigned vlen,
                                          unsigned ch_left)
  {
      if (vr->type == 2)
          return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, ch_left, 2);
      else if (vr->type == 1)
          return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, ch_left, 1);
      else if (vr->type == 0)
          return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, ch_left, 0);
      else {
          av_log(vc->avctx, AV_LOG_ERROR, " Invalid residue type while residue decode?! \n");
          return AVERROR_INVALIDDATA;
      }
  }
  
  void ff_vorbis_inverse_coupling(float *mag, float *ang, intptr_t blocksize)
  {
      int i;
      for (i = 0;  i < blocksize;  i++) {
          if (mag[i] > 0.0) {
              if (ang[i] > 0.0) {
                  ang[i] = mag[i] - ang[i];
              } else {
                  float temp = ang[i];
                  ang[i]     = mag[i];
                  mag[i]    += temp;
              }
          } else {
              if (ang[i] > 0.0) {
                  ang[i] += mag[i];
              } else {
                  float temp = ang[i];
                  ang[i]     = mag[i];
                  mag[i]    -= temp;
              }
          }
      }
  }
  
  // Decode the audio packet using the functions above
  
  static int vorbis_parse_audio_packet(vorbis_context *vc, float **floor_ptr)
  {
      GetBitContext *gb = &vc->gb;
      FFTContext *mdct;
      int previous_window = vc->previous_window;
      unsigned mode_number, blockflag, blocksize;
      int i, j;
      uint8_t no_residue[255];
      uint8_t do_not_decode[255];
      vorbis_mapping *mapping;
      float *ch_res_ptr   = vc->channel_residues;
      uint8_t res_chan[255];
      unsigned res_num = 0;
      int retlen  = 0;
      unsigned ch_left = vc->audio_channels;
      unsigned vlen;
  
      if (get_bits1(gb)) {
          av_log(vc->avctx, AV_LOG_ERROR, "Not a Vorbis I audio packet.\n");
          return AVERROR_INVALIDDATA; // packet type not audio
      }
  
      if (vc->mode_count == 1) {
          mode_number = 0;
      } else {
          GET_VALIDATED_INDEX(mode_number, ilog(vc->mode_count-1), vc->mode_count)
      }
      vc->mode_number = mode_number;
      mapping = &vc->mappings[vc->modes[mode_number].mapping];
  
      av_dlog(NULL, " Mode number: %u , mapping: %d , blocktype %d\n", mode_number,
              vc->modes[mode_number].mapping, vc->modes[mode_number].blockflag);
  
      blockflag = vc->modes[mode_number].blockflag;
      blocksize = vc->blocksize[blockflag];
      vlen = blocksize / 2;
      if (blockflag) {
          int code = get_bits(gb, 2);
          if (previous_window < 0)
              previous_window = code>>1;
      } else if (previous_window < 0)
          previous_window = 0;
  
      memset(ch_res_ptr,   0, sizeof(float) * vc->audio_channels * vlen); //FIXME can this be removed ?
      for (i = 0; i < vc->audio_channels; ++i)
          memset(floor_ptr[i], 0, vlen * sizeof(floor_ptr[0][0])); //FIXME can this be removed ?
  
  // Decode floor
  
      for (i = 0; i < vc->audio_channels; ++i) {
          vorbis_floor *floor;
          int ret;
          if (mapping->submaps > 1) {
              floor = &vc->floors[mapping->submap_floor[mapping->mux[i]]];
          } else {
              floor = &vc->floors[mapping->submap_floor[0]];
          }
  
          ret = floor->decode(vc, &floor->data, floor_ptr[i]);
  
          if (ret < 0) {
              av_log(vc->avctx, AV_LOG_ERROR, "Invalid codebook in vorbis_floor_decode.\n");
              return AVERROR_INVALIDDATA;
          }
          no_residue[i] = ret;
      }
  
  // Nonzero vector propagate
  
      for (i = mapping->coupling_steps - 1; i >= 0; --i) {
          if (!(no_residue[mapping->magnitude[i]] & no_residue[mapping->angle[i]])) {
              no_residue[mapping->magnitude[i]] = 0;
              no_residue[mapping->angle[i]]     = 0;
          }
      }
  
  // Decode residue
  
      for (i = 0; i < mapping->submaps; ++i) {
          vorbis_residue *residue;
          unsigned ch = 0;
          int ret;
  
          for (j = 0; j < vc->audio_channels; ++j) {
              if ((mapping->submaps == 1) || (i == mapping->mux[j])) {
                  res_chan[j] = res_num;
                  if (no_residue[j]) {
                      do_not_decode[ch] = 1;
                  } else {
                      do_not_decode[ch] = 0;
                  }
                  ++ch;
                  ++res_num;
              }
          }
          residue = &vc->residues[mapping->submap_residue[i]];
          if (ch_left < ch) {
              av_log(vc->avctx, AV_LOG_ERROR, "Too many channels in vorbis_floor_decode.\n");
              return AVERROR_INVALIDDATA;
          }
          if (ch) {
              ret = vorbis_residue_decode(vc, residue, ch, do_not_decode, ch_res_ptr, vlen, ch_left);
              if (ret < 0)
                  return ret;
          }
  
          ch_res_ptr += ch * vlen;
          ch_left -= ch;
      }
  
      if (ch_left > 0)
          return AVERROR_INVALIDDATA;
  
  // Inverse coupling
  
      for (i = mapping->coupling_steps - 1; i >= 0; --i) { //warning: i has to be signed
          float *mag, *ang;
  
          mag = vc->channel_residues+res_chan[mapping->magnitude[i]] * blocksize / 2;
          ang = vc->channel_residues+res_chan[mapping->angle[i]]     * blocksize / 2;
          vc->dsp.vorbis_inverse_coupling(mag, ang, blocksize / 2);
      }
  
  // Dotproduct, MDCT
  
      mdct = &vc->mdct[blockflag];
  
      for (j = vc->audio_channels-1;j >= 0; j--) {
          ch_res_ptr   = vc->channel_residues + res_chan[j] * blocksize / 2;
          vc->fdsp.vector_fmul(floor_ptr[j], floor_ptr[j], ch_res_ptr, blocksize / 2);
          mdct->imdct_half(mdct, ch_res_ptr, floor_ptr[j]);
      }
  
  // Overlap/add, save data for next overlapping
  
      retlen = (blocksize + vc->blocksize[previous_window]) / 4;
      for (j = 0; j < vc->audio_channels; j++) {
          unsigned bs0 = vc->blocksize[0];
          unsigned bs1 = vc->blocksize[1];
          float *residue    = vc->channel_residues + res_chan[j] * blocksize / 2;
          float *saved      = vc->saved + j * bs1 / 4;
          float *ret        = floor_ptr[j];
          float *buf        = residue;
          const float *win  = vc->win[blockflag & previous_window];
  
          if (blockflag == previous_window) {
              vc->fdsp.vector_fmul_window(ret, saved, buf, win, blocksize / 4);
          } else if (blockflag > previous_window) {
              vc->fdsp.vector_fmul_window(ret, saved, buf, win, bs0 / 4);
              memcpy(ret+bs0/2, buf+bs0/4, ((bs1-bs0)/4) * sizeof(float));
          } else {
              memcpy(ret, saved, ((bs1 - bs0) / 4) * sizeof(float));
              vc->fdsp.vector_fmul_window(ret + (bs1 - bs0) / 4, saved + (bs1 - bs0) / 4, buf, win, bs0 / 4);
          }
          memcpy(saved, buf + blocksize / 4, blocksize / 4 * sizeof(float));
      }
  
      vc->previous_window = blockflag;
      return retlen;
  }
  
  // Return the decoded audio packet through the standard api
  
  static int vorbis_decode_frame(AVCodecContext *avctx, void *data,
                                 int *got_frame_ptr, AVPacket *avpkt)
  {
      const uint8_t *buf = avpkt->data;
      int buf_size       = avpkt->size;
      vorbis_context *vc = avctx->priv_data;
      AVFrame *frame     = data;
      GetBitContext *gb = &vc->gb;
      float *channel_ptrs[255];
      int i, len, ret;
  
      av_dlog(NULL, "packet length %d \n", buf_size);
  
      if (*buf == 1 && buf_size > 7) {
          init_get_bits(gb, buf+1, buf_size*8 - 8);
          vorbis_free(vc);
          if ((ret = vorbis_parse_id_hdr(vc))) {
              av_log(avctx, AV_LOG_ERROR, "Id header corrupt.\n");
              vorbis_free(vc);
              return ret;
          }
  
          if (vc->audio_channels > 8)
              avctx->channel_layout = 0;
          else
              avctx->channel_layout = ff_vorbis_channel_layouts[vc->audio_channels - 1];
  
          avctx->channels    = vc->audio_channels;
          avctx->sample_rate = vc->audio_samplerate;
          return buf_size;
      }
  
      if (*buf == 3 && buf_size > 7) {
          av_log(avctx, AV_LOG_DEBUG, "Ignoring comment header\n");
          return buf_size;
      }
  
      if (*buf == 5 && buf_size > 7 && vc->channel_residues && !vc->modes) {
          init_get_bits(gb, buf+1, buf_size*8 - 8);
          if ((ret = vorbis_parse_setup_hdr(vc))) {
              av_log(avctx, AV_LOG_ERROR, "Setup header corrupt.\n");
              vorbis_free(vc);
              return ret;
          }
          return buf_size;
      }
  
      if (!vc->channel_residues || !vc->modes) {
          av_log(avctx, AV_LOG_ERROR, "Data packet before valid headers\n");
          return AVERROR_INVALIDDATA;
      }
  
      /* get output buffer */
      frame->nb_samples = vc->blocksize[1] / 2;
      if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
          return ret;
  
      if (vc->audio_channels > 8) {
          for (i = 0; i < vc->audio_channels; i++)
              channel_ptrs[i] = (float *)frame->extended_data[i];
      } else {
          for (i = 0; i < vc->audio_channels; i++) {
              int ch = ff_vorbis_channel_layout_offsets[vc->audio_channels - 1][i];
              channel_ptrs[ch] = (float *)frame->extended_data[i];
          }
      }
  
      init_get_bits(gb, buf, buf_size*8);
  
      if ((len = vorbis_parse_audio_packet(vc, channel_ptrs)) <= 0)
          return len;
  
      if (!vc->first_frame) {
          vc->first_frame = 1;
          *got_frame_ptr = 0;
          av_frame_unref(frame);
          return buf_size;
      }
  
      av_dlog(NULL, "parsed %d bytes %d bits, returned %d samples (*ch*bits) \n",
              get_bits_count(gb) / 8, get_bits_count(gb) % 8, len);
  
      frame->nb_samples = len;
      *got_frame_ptr    = 1;
  
      return buf_size;
  }
  
  // Close decoder
  
  static av_cold int vorbis_decode_close(AVCodecContext *avctx)
  {
      vorbis_context *vc = avctx->priv_data;
  
      vorbis_free(vc);
  
      return 0;
  }
  
  static av_cold void vorbis_decode_flush(AVCodecContext *avctx)
  {
      vorbis_context *vc = avctx->priv_data;
  
      if (vc->saved) {
          memset(vc->saved, 0, (vc->blocksize[1] / 4) * vc->audio_channels *
                               sizeof(*vc->saved));
      }
      vc->previous_window = -1;
      vc->first_frame = 0;
  }
  
  AVCodec ff_vorbis_decoder = {
      .name            = "vorbis",
      .long_name       = NULL_IF_CONFIG_SMALL("Vorbis"),
      .type            = AVMEDIA_TYPE_AUDIO,
      .id              = AV_CODEC_ID_VORBIS,
      .priv_data_size  = sizeof(vorbis_context),
      .init            = vorbis_decode_init,
      .close           = vorbis_decode_close,
      .decode          = vorbis_decode_frame,
      .flush           = vorbis_decode_flush,
      .capabilities    = CODEC_CAP_DR1,
      .channel_layouts = ff_vorbis_channel_layouts,
      .sample_fmts     = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
                                                         AV_SAMPLE_FMT_NONE },
  };
  