/**

  * @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
  */
 

 #include <inttypes.h>

 #include <math.h>
 
 #define ALT_BITSTREAM_READER_LE
 #include "avcodec.h"

 #include "get_bits.h"

 #include "dsputil.h"

 #include "fft.h"

 #include "fmtconvert.h"

 
 #include "vorbis.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)

 
 #undef NDEBUG
 #include <assert.h>
 
 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 *avccontext;
     GetBitContext gb;
     DSPContext dsp;

     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
     uint8_t       previous_window;

     float        *channel_residues;
     float        *channel_floors;
     float        *saved;

     float         scale_bias; // for float->int conversion

 } 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->avccontext, AV_LOG_ERROR,\
                idx_err_str,\
                (int)(idx), (int)(limit - 1), #idx, __FILE__, __LINE__);\
         return -1;\
     }
 #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->channel_floors);
     av_freep(&vc->saved);
 

     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]);
 

     for (i = 0; i < vc->codebook_count; ++i) {

         av_free(vc->codebooks[i].codevectors);
         free_vlc(&vc->codebooks[i].vlc);
     }
     av_freep(&vc->codebooks);
 

     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);
 

     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;

     uint32_t *tmp_vlc_codes;

     GetBitContext *gb = &vc->gb;

     uint16_t *codebook_multiplicands;

     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));

     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->avccontext, AV_LOG_ERROR,
                    " %u. Codebook setup data corrupt.\n", cb);

             goto error;
         }
 
         codebook_setup->dimensions=get_bits(gb, 16);

         if (codebook_setup->dimensions > 16 || codebook_setup->dimensions == 0) {

             av_log(vc->avccontext, AV_LOG_ERROR,
                    " %u. Codebook's dimension is invalid (%d).\n",
                    cb, codebook_setup->dimensions);

             goto error;
         }

         entries = get_bits(gb, 24);
         if (entries > V_MAX_VLCS) {

             av_log(vc->avccontext, AV_LOG_ERROR,
                    " %u. Codebook has too many entries (%u).\n",
                    cb, entries);

             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->avccontext, AV_LOG_ERROR, " More codelengths than codes in codebook. \n");
                 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(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->avccontext, "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->avccontext, "real lookup offset %u, vector: ", j);

                     for (k = 0; k < dim; ++k)

                         av_dlog(vc->avccontext, " %f ",
                                 codebook_setup->codevectors[j * dim + k]);
                     av_dlog(vc->avccontext, "\n");

 
                     ++j;
                 }
             }

             if (j != used_entries) {

                 av_log(vc->avccontext, AV_LOG_ERROR, "Bug in codevector vector building code. \n");
                 goto error;
             }

             entries = used_entries;
         } else if (codebook_setup->lookup_type >= 2) {

             av_log(vc->avccontext, AV_LOG_ERROR, "Codebook lookup type not supported. \n");
             goto error;
         }
 
 // Initialize VLC table
         if (ff_vorbis_len2vlc(tmp_vlc_bits, tmp_vlc_codes, entries)) {
             av_log(vc->avccontext, AV_LOG_ERROR, " Invalid code lengths while generating vlcs. \n");
             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 (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->avccontext, 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 -1;

 }
 
 // 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->avccontext, AV_LOG_ERROR, "Vorbis time domain transform data nonzero. \n");

             return -1;

         }
     }
     return 0;
 }
 
 // Process floors part
 

 static int vorbis_floor0_decode(vorbis_context *vc,
                                 vorbis_floor_data *vfu, float *vec);

 static void 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;

     vc->floor_count = get_bits(gb, 6) + 1;

     vc->floors = av_mallocz(vc->floor_count * sizeof(*vc->floors));

     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(floor_setup->data.t1.x_list_dim *
                                                    sizeof(*floor_setup->data.t1.list));

             rangebits = get_bits(gb, 4);

             rangemax = (1 << rangebits);
             if (rangemax > vc->blocksize[1] / 2) {
                 av_log(vc->avccontext, AV_LOG_ERROR,

                        "Floor value is too large for blocksize: %u (%"PRIu32")\n",

                        rangemax, vc->blocksize[1] / 2);
                 return -1;
             }

             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
             ff_vorbis_ready_floor1_list(floor_setup->data.t1.list, floor_setup->data.t1.x_list_dim);

         } 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);
             floor_setup->data.t0.rate           = get_bits(gb, 16);
             floor_setup->data.t0.bark_map_size  = get_bits(gb, 16);
             floor_setup->data.t0.amplitude_bits = get_bits(gb,  6);

             /* zero would result in a div by zero later *
              * 2^0 - 1 == 0                             */
             if (floor_setup->data.t0.amplitude_bits == 0) {

                 av_log(vc->avccontext, AV_LOG_ERROR,
                        "Floor 0 amplitude bits is 0.\n");
                 return -1;

             }

             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 -1;

             /* 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;

                 }
             }
 

             create_map(vc, i);

             /* 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((floor_setup->data.t0.order + 1 + max_codebook_dim)
                           * sizeof(*floor_setup->data.t0.lsp));

             if (!floor_setup->data.t0.lsp)
                 return -1;

             /* 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->avccontext, AV_LOG_ERROR, "Invalid floor type!\n");

             return -1;

         }
     }
     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));

     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 > vc->avccontext->channels * vc->blocksize[1] / 2 ||

             (res_setup->end-res_setup->begin) / res_setup->partition_size > V_MAX_PARTITIONS) {

             av_log(vc->avccontext, 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 -1;

         }
 

         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(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));

     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->avccontext, AV_LOG_ERROR, "Other mappings than type 0 are not compliant with the Vorbis I specification. \n");

             return -1;

         }
         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));

             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->avccontext, AV_LOG_ERROR, "%u. mapping setup data invalid.\n", i);

             return -1; // following spec.

         }
 
         if (mapping_setup->submaps>1) {

             mapping_setup->mux = av_mallocz(vc->audio_channels *
                                             sizeof(*mapping_setup->mux));

             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 void 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((n + 1) * sizeof(int32_t)); // n + sentinel

         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]);

     }
 }
 

 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));

     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;

     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->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (no vorbis signature). \n");

         return -1;

     }
 
     if (vorbis_parse_setup_hdr_codebooks(vc)) {
         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (codebooks). \n");

         return -2;

     }
     if (vorbis_parse_setup_hdr_tdtransforms(vc)) {
         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (time domain transforms). \n");

         return -3;

     }
     if (vorbis_parse_setup_hdr_floors(vc)) {
         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (floors). \n");

         return -4;

     }
     if (vorbis_parse_setup_hdr_residues(vc)) {
         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (residues). \n");

         return -5;

     }
     if (vorbis_parse_setup_hdr_mappings(vc)) {
         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (mappings). \n");

         return -6;

     }
     if (vorbis_parse_setup_hdr_modes(vc)) {
         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (modes). \n");

         return -7;

     }
     if (!get_bits1(gb)) {
         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis setup header packet corrupt (framing flag). \n");

         return -8; // 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->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (no vorbis signature). \n");

         return -1;

     }
 

     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->avccontext, AV_LOG_ERROR, "Invalid number of channels\n");
         return -1;
     }

     vc->audio_samplerate = get_bits_long(gb, 32);
     if (vc->audio_samplerate <= 0) {

         av_log(vc->avccontext, AV_LOG_ERROR, "Invalid samplerate\n");
         return -1;
     }

     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);
     vc->blocksize[0] = (1 << bl0);
     vc->blocksize[1] = (1 << bl1);
     if (bl0 > 13 || bl0 < 6 || bl1 > 13 || bl1 < 6 || bl1 < bl0) {

         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (illegal blocksize). \n");

         return -3;

     }
     // output format int16

     if (vc->blocksize[1] / 2 * vc->audio_channels * 2 > AVCODEC_MAX_AUDIO_FRAME_SIZE) {

         av_log(vc->avccontext, AV_LOG_ERROR, "Vorbis channel count makes "
                "output packets too large.\n");

         return -4;

     }

     vc->win[0] = ff_vorbis_vwin[bl0 - 6];
     vc->win[1] = ff_vorbis_vwin[bl1 - 6];

 
     if ((get_bits1(gb)) == 0) {
         av_log(vc->avccontext, AV_LOG_ERROR, " Vorbis id header packet corrupt (framing flag not set). \n");

         return -2;

     }
 

     vc->channel_residues =  av_malloc((vc->blocksize[1]  / 2) * vc->audio_channels * sizeof(*vc->channel_residues));
     vc->channel_floors   =  av_malloc((vc->blocksize[1]  / 2) * vc->audio_channels * sizeof(*vc->channel_floors));
     vc->saved            =  av_mallocz((vc->blocksize[1] / 4) * vc->audio_channels * sizeof(*vc->saved));

     vc->previous_window  = 0;

     ff_mdct_init(&vc->mdct[0], bl0, 1, -vc->scale_bias);
     ff_mdct_init(&vc->mdct[1], bl1, 1, -vc->scale_bias);

     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 *avccontext)
 {

     vorbis_context *vc = avccontext->priv_data ;

     uint8_t *headers   = avccontext->extradata;
     int headers_len    = avccontext->extradata_size;

     uint8_t *header_start[3];
     int header_len[3];
     GetBitContext *gb = &(vc->gb);
     int hdr_type;
 
     vc->avccontext = avccontext;
     dsputil_init(&vc->dsp, avccontext);

     ff_fmt_convert_init(&vc->fmt_conv, avccontext);

     if (avccontext->request_sample_fmt == AV_SAMPLE_FMT_FLT) {
         avccontext->sample_fmt = AV_SAMPLE_FMT_FLT;
         vc->scale_bias = 1.0f;
     } else {
         avccontext->sample_fmt = AV_SAMPLE_FMT_S16;
         vc->scale_bias = 32768.0f;
     }

 
     if (!headers_len) {

         av_log(avccontext, AV_LOG_ERROR, "Extradata missing.\n");

         return -1;
     }
 
     if (ff_split_xiph_headers(headers, headers_len, 30, header_start, header_len) < 0) {
         av_log(avccontext, AV_LOG_ERROR, "Extradata corrupt.\n");
         return -1;
     }
 
     init_get_bits(gb, header_start[0], header_len[0]*8);

     hdr_type = get_bits(gb, 8);
     if (hdr_type != 1) {

         av_log(avccontext, AV_LOG_ERROR, "First header is not the id header.\n");
         return -1;
     }
     if (vorbis_parse_id_hdr(vc)) {
         av_log(avccontext, AV_LOG_ERROR, "Id header corrupt.\n");
         vorbis_free(vc);
         return -1;
     }
 
     init_get_bits(gb, header_start[2], header_len[2]*8);

     hdr_type = get_bits(gb, 8);
     if (hdr_type != 5) {

         av_log(avccontext, AV_LOG_ERROR, "Third header is not the setup header.\n");

         vorbis_free(vc);

         return -1;
     }
     if (vorbis_parse_setup_hdr(vc)) {
         av_log(avccontext, AV_LOG_ERROR, "Setup header corrupt.\n");
         vorbis_free(vc);
         return -1;
     }
 

     if (vc->audio_channels > 8)

         avccontext->channel_layout = 0;
     else
         avccontext->channel_layout = ff_vorbis_channel_layouts[vc->audio_channels - 1];
 

     avccontext->channels    = vc->audio_channels;

     avccontext->sample_rate = vc->audio_samplerate;

     avccontext->frame_size  = FFMIN(vc->blocksize[0], vc->blocksize[1]) >> 2;

 
     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;

     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->avccontext, 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 -1;

 
         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) {
                 floor1_Y[offset+j] = get_vlc2(gb, vc->codebooks[book].vlc.table,

                 vc->codebooks[book].nb_bits, 3);
             } 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 mispelling

         }
         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] = val - lowroom + predicted;

                 } else {

                     floor1_Y_final[i] = predicted - val + highroom - 1;

                 }
             } else {
                 if (val & 1) {

                     floor1_Y_final[i] = predicted - (val + 1) / 2;

                 } else {

                     floor1_Y_final[i] = predicted + val / 2;

                 }
             }
         } else {

             floor1_flag[i]    = 0;
             floor1_Y_final[i] = 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;
 }
 
 // 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,

                                                            int vr_type)

 {

     GetBitContext *gb = &vc->gb;

     unsigned c_p_c        = vc->codebooks[vr->classbook].dimensions;
     unsigned ptns_to_read = vr->ptns_to_read;

     uint8_t *classifs = vr->classifs;

     unsigned pass, ch_used, i, j, k, l;

     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;

     } else {

         ch_used = ch;

     }
 

     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?

         uint16_t voffset, partition_count, j_times_ptns_to_read;

         voffset = vr->begin;
         for (partition_count = 0; partition_count < ptns_to_read;) {  // SPEC        error

             if (!pass) {

                 unsigned inverse_class = ff_inverse[vr->classifications];

                 for (j_times_ptns_to_read = 0, j = 0; j < ch_used; ++j) {

                     if (!do_not_decode[j]) {

                         unsigned temp = get_vlc2(gb, vc->codebooks[vr->classbook].vlc.table,
                                                  vc->codebooks[vr->classbook].nb_bits, 3);

                         av_dlog(NULL, "Classword: %u\n", temp);

                         assert(vr->classifications > 1 && temp <= 65536); //needed for inverse[]
                         for (i = 0; i < c_p_c; ++i) {

                             unsigned temp2;

                             temp2 = (((uint64_t)temp) * inverse_class) >> 32;

                             if (partition_count + c_p_c - 1 - i < ptns_to_read)
                                 classifs[j_times_ptns_to_read + partition_count + c_p_c - 1 - i] = temp - temp2 * vr->classifications;
                             temp = temp2;

                         }
                     }

                     j_times_ptns_to_read += ptns_to_read;

                 }
             }

             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 = dim == 1 ? vr->partition_size
                                                      : FASTDIV(vr->partition_size, dim);

                             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];  // FPMATH

                                 }

                             } 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];  // FPMATH
 

                                         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    ];  // FPMATH
                                         vec[voffs + k + vlen] += codebook.codevectors[coffs + 1];  // FPMATH

                                     }

                                 } 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    ];  // FPMATH
                                         vec[voffs + 1       ] += codebook.codevectors[coffs + 2];  // FPMATH
                                         vec[voffs + vlen    ] += codebook.codevectors[coffs + 1];  // FPMATH
                                         vec[voffs + vlen + 1] += codebook.codevectors[coffs + 3];  // FPMATH

                                     }

                                 } 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    ];  // FPMATH
                                         vec[voffs + vlen] += codebook.codevectors[coffs + l + 1];  // FPMATH

                                         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) {
                                 voffs = voffset;

                                 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 / ch + (voffs % ch) * vlen] += codebook.codevectors[coffs + l];  // FPMATH FIXME use if and counter instead of / and %

                                         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);

                                     }
                                 }
                             }
                         }
                     }

                     j_times_ptns_to_read += ptns_to_read;

                 }
                 ++partition_count;

                 voffset += vr->partition_size;

             }
         }
     }
     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)

 {

     if (vr->type == 2)

         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 2);

     else if (vr->type == 1)

         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 1);

     else if (vr->type == 0)

         return vorbis_residue_decode_internal(vc, vr, ch, do_not_decode, vec, vlen, 0);
     else {
         av_log(vc->avccontext, AV_LOG_ERROR, " Invalid residue type while residue decode?! \n");

         return -1;

     }
 }
 

 void vorbis_inverse_coupling(float *mag, float *ang, int 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)
 {

     GetBitContext *gb = &vc->gb;

     FFTContext *mdct;

     unsigned 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;
     float *ch_floor_ptr = vc->channel_floors;

     uint8_t res_chan[255];

     unsigned res_num = 0;
     int retlen  = 0;

 
     if (get_bits1(gb)) {
         av_log(vc->avccontext, AV_LOG_ERROR, "Not a Vorbis I audio packet.\n");
         return -1; // 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];

     if (blockflag)

         skip_bits(gb, 2); // previous_window, next_window

     memset(ch_res_ptr,   0, sizeof(float) * vc->audio_channels * blocksize / 2); //FIXME can this be removed ?
     memset(ch_floor_ptr, 0, sizeof(float) * vc->audio_channels * blocksize / 2); //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, ch_floor_ptr);
 
         if (ret < 0) {
             av_log(vc->avccontext, AV_LOG_ERROR, "Invalid codebook in vorbis_floor_decode.\n");
             return -1;
         }
         no_residue[i] = ret;

         ch_floor_ptr += blocksize / 2;

     }
 
 // 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;

         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]];

         vorbis_residue_decode(vc, residue, ch, do_not_decode, ch_res_ptr, blocksize/2);
 

         ch_res_ptr += ch * blocksize / 2;

     }
 
 // 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_floor_ptr = vc->channel_floors   + j           * blocksize / 2;
         ch_res_ptr   = vc->channel_residues + res_chan[j] * blocksize / 2;

         vc->dsp.vector_fmul(ch_floor_ptr, ch_floor_ptr, ch_res_ptr, blocksize / 2);

         mdct->imdct_half(mdct, ch_res_ptr, ch_floor_ptr);

     }
 

 // Overlap/add, save data for next overlapping  FPMATH

     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        = vc->channel_floors + j * retlen;
         float *buf        = residue;
         const float *win  = vc->win[blockflag & previous_window];
 
         if (blockflag == previous_window) {

             vc->dsp.vector_fmul_window(ret, saved, buf, win, blocksize / 4);

         } else if (blockflag > previous_window) {

             vc->dsp.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->dsp.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 *avccontext,

                                void *data, int *data_size,
                                AVPacket *avpkt)

 {

     const uint8_t *buf = avpkt->data;

     int buf_size       = avpkt->size;

     vorbis_context *vc = avccontext->priv_data ;
     GetBitContext *gb = &(vc->gb);

     const float *channel_ptrs[255];

     int i, len, out_size;

     if (!buf_size)

         return 0;
 

     av_dlog(NULL, "packet length %d \n", buf_size);

 
     init_get_bits(gb, buf, buf_size*8);
 

     len = vorbis_parse_audio_packet(vc);

     if (len <= 0) {
         *data_size = 0;

         return buf_size;
     }
 
     if (!vc->first_frame) {

         vc->first_frame = 1;
         *data_size = 0;

         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);

     out_size = len * vc->audio_channels *
                av_get_bytes_per_sample(avccontext->sample_fmt);
     if (*data_size < out_size) {
         av_log(avccontext, AV_LOG_ERROR, "output buffer is too small\n");
         return AVERROR(EINVAL);
     }
 

     if (vc->audio_channels > 8) {

         for (i = 0; i < vc->audio_channels; i++)
             channel_ptrs[i] = vc->channel_floors + i * len;

     } else {
         for (i = 0; i < vc->audio_channels; i++)
             channel_ptrs[i] = vc->channel_floors +
                               len * ff_vorbis_channel_layout_offsets[vc->audio_channels - 1][i];
     }
 

     if (avccontext->sample_fmt == AV_SAMPLE_FMT_FLT)
         vc->fmt_conv.float_interleave(data, channel_ptrs, len, vc->audio_channels);
     else

         vc->fmt_conv.float_to_int16_interleave(data, channel_ptrs, len,
                                                vc->audio_channels);

     *data_size = out_size;

 
     return buf_size ;
 }
 
 // Close decoder
 

 static av_cold int vorbis_decode_close(AVCodecContext *avccontext)
 {

     vorbis_context *vc = avccontext->priv_data;
 
     vorbis_free(vc);
 
     return 0 ;
 }
 

 AVCodec ff_vorbis_decoder = {

     "vorbis",

     AVMEDIA_TYPE_AUDIO,

     CODEC_ID_VORBIS,
     sizeof(vorbis_context),
     vorbis_decode_init,
     NULL,
     vorbis_decode_close,
     vorbis_decode_frame,

     .long_name = NULL_IF_CONFIG_SMALL("Vorbis"),

     .channel_layouts = ff_vorbis_channel_layouts,

     .sample_fmts = (const enum AVSampleFormat[]) {
         AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_NONE
     },

 };