/*
  * copyright (c) 2006 Oded Shimon <ods15@ods15.dyndns.org>
  *

  * 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

  * Native Vorbis encoder.
  * @author Oded Shimon <ods15@ods15.dyndns.org>
  */
 

 #include <float.h>

 #include "avcodec.h"

 #include "internal.h"

 #include "fft.h"

 #include "mathops.h"

 #include "vorbis.h"

 #include "vorbis_enc_data.h"

 #define BITSTREAM_WRITER_LE

 #include "put_bits.h"

 #undef NDEBUG
 #include <assert.h>
 

 typedef struct vorbis_enc_codebook {

     int nentries;

     uint8_t *lens;
     uint32_t *codewords;

     int ndimensions;

     float min;
     float delta;
     int seq_p;
     int lookup;

     int *quantlist;

     float *dimensions;

     float *pow2;

 } vorbis_enc_codebook;

 typedef struct vorbis_enc_floor_class {

     int dim;
     int subclass;
     int masterbook;

     int *books;

 } vorbis_enc_floor_class;

 typedef struct vorbis_enc_floor {

     int partitions;

     int *partition_to_class;

     int nclasses;

     vorbis_enc_floor_class *classes;

     int multiplier;
     int rangebits;
     int values;

     vorbis_floor1_entry *list;

 } vorbis_enc_floor;

 typedef struct vorbis_enc_residue {

     int type;
     int begin;
     int end;
     int partition_size;
     int classifications;
     int classbook;

     int8_t (*books)[8];

     float (*maxes)[2];

 } vorbis_enc_residue;

 typedef struct vorbis_enc_mapping {

     int submaps;

     int *mux;
     int *floor;
     int *residue;

     int coupling_steps;

     int *magnitude;
     int *angle;

 } vorbis_enc_mapping;

 typedef struct vorbis_enc_mode {

     int blockflag;
     int mapping;

 } vorbis_enc_mode;

 typedef struct vorbis_enc_context {

     int channels;
     int sample_rate;

     int log2_blocksize[2];

     FFTContext mdct[2];

     const float *win[2];

     int have_saved;

     float *saved;
     float *samples;
     float *floor;  // also used for tmp values for mdct
     float *coeffs; // also used for residue after floor

     float quality;

     int ncodebooks;

     vorbis_enc_codebook *codebooks;

 
     int nfloors;

     vorbis_enc_floor *floors;

 
     int nresidues;

     vorbis_enc_residue *residues;

 
     int nmappings;

     vorbis_enc_mapping *mappings;

 
     int nmodes;

     vorbis_enc_mode *modes;

     int64_t next_pts;

 } vorbis_enc_context;

 #define MAX_CHANNELS     2
 #define MAX_CODEBOOK_DIM 8
 
 #define MAX_FLOOR_CLASS_DIM  4
 #define NUM_FLOOR_PARTITIONS 8
 #define MAX_FLOOR_VALUES     (MAX_FLOOR_CLASS_DIM*NUM_FLOOR_PARTITIONS+2)
 
 #define RESIDUE_SIZE           1600
 #define RESIDUE_PART_SIZE      32
 #define NUM_RESIDUE_PARTITIONS (RESIDUE_SIZE/RESIDUE_PART_SIZE)
 

 static inline int put_codeword(PutBitContext *pb, vorbis_enc_codebook *cb,
                                int entry)

 {

     av_assert2(entry >= 0);
     av_assert2(entry < cb->nentries);
     av_assert2(cb->lens[entry]);

     if (pb->size_in_bits - put_bits_count(pb) < cb->lens[entry])
         return AVERROR(EINVAL);

     put_bits(pb, cb->lens[entry], cb->codewords[entry]);

     return 0;

 }
 

 static int cb_lookup_vals(int lookup, int dimensions, int entries)

 {
     if (lookup == 1)

         return ff_vorbis_nth_root(entries, dimensions);

     else if (lookup == 2)

         return dimensions *entries;

     return 0;
 }
 

 static int ready_codebook(vorbis_enc_codebook *cb)

 {

     int i;
 

     ff_vorbis_len2vlc(cb->lens, cb->codewords, cb->nentries);

     if (!cb->lookup) {

         cb->pow2 = cb->dimensions = NULL;

     } else {

         int vals = cb_lookup_vals(cb->lookup, cb->ndimensions, cb->nentries);

         cb->dimensions = av_malloc_array(cb->nentries, sizeof(float) * cb->ndimensions);
         cb->pow2 = av_mallocz_array(cb->nentries, sizeof(float));

         if (!cb->dimensions || !cb->pow2)

             return AVERROR(ENOMEM);

         for (i = 0; i < cb->nentries; i++) {
             float last = 0;
             int j;
             int div = 1;

             for (j = 0; j < cb->ndimensions; j++) {

                 int off;

                 if (cb->lookup == 1)
                     off = (i / div) % vals; // lookup type 1
                 else

                     off = i * cb->ndimensions + j; // lookup type 2

                 cb->dimensions[i * cb->ndimensions + j] = last + cb->min + cb->quantlist[off] * cb->delta;

                 if (cb->seq_p)

                     last = cb->dimensions[i * cb->ndimensions + j];
                 cb->pow2[i] += cb->dimensions[i * cb->ndimensions + j] * cb->dimensions[i * cb->ndimensions + j];

                 div *= vals;
             }

             cb->pow2[i] /= 2.0;

         }
     }

     return 0;

 }
 

 static int ready_residue(vorbis_enc_residue *rc, vorbis_enc_context *venc)

 {

     int i;

     av_assert0(rc->type == 2);

     rc->maxes = av_mallocz_array(rc->classifications, sizeof(float[2]));

     if (!rc->maxes)
         return AVERROR(ENOMEM);

     for (i = 0; i < rc->classifications; i++) {
         int j;

         vorbis_enc_codebook * cb;

         for (j = 0; j < 8; j++)

             if (rc->books[i][j] != -1)
                 break;

         if (j == 8) // zero
             continue;

         cb = &venc->codebooks[rc->books[i][j]];

         assert(cb->ndimensions >= 2);

         assert(cb->lookup);
 
         for (j = 0; j < cb->nentries; j++) {
             float a;

             if (!cb->lens[j])
                 continue;

             a = fabs(cb->dimensions[j * cb->ndimensions]);

             if (a > rc->maxes[i][0])
                 rc->maxes[i][0] = a;

             a = fabs(cb->dimensions[j * cb->ndimensions + 1]);

             if (a > rc->maxes[i][1])
                 rc->maxes[i][1] = a;

         }
     }
     // small bias
     for (i = 0; i < rc->classifications; i++) {
         rc->maxes[i][0] += 0.8;
         rc->maxes[i][1] += 0.8;
     }

     return 0;

 }
 

 static int create_vorbis_context(vorbis_enc_context *venc,

                                  AVCodecContext *avctx)

 {

     vorbis_enc_floor   *fc;
     vorbis_enc_residue *rc;
     vorbis_enc_mapping *mc;

     int i, book, ret;

     venc->channels    = avctx->channels;
     venc->sample_rate = avctx->sample_rate;

     venc->log2_blocksize[0] = venc->log2_blocksize[1] = 11;

     venc->ncodebooks = FF_ARRAY_ELEMS(cvectors);

     venc->codebooks  = av_malloc(sizeof(vorbis_enc_codebook) * venc->ncodebooks);

     if (!venc->codebooks)
         return AVERROR(ENOMEM);

     // codebook 0..14 - floor1 book, values 0..255

     // codebook 15 residue masterbook
     // codebook 16..29 residue
     for (book = 0; book < venc->ncodebooks; book++) {

         vorbis_enc_codebook *cb = &venc->codebooks[book];

         int vals;

         cb->ndimensions = cvectors[book].dim;

         cb->nentries    = cvectors[book].real_len;
         cb->min         = cvectors[book].min;
         cb->delta       = cvectors[book].delta;
         cb->lookup      = cvectors[book].lookup;
         cb->seq_p       = 0;

         cb->lens      = av_malloc_array(cb->nentries, sizeof(uint8_t));
         cb->codewords = av_malloc_array(cb->nentries, sizeof(uint32_t));

         if (!cb->lens || !cb->codewords)
             return AVERROR(ENOMEM);

         memcpy(cb->lens, cvectors[book].clens, cvectors[book].len);
         memset(cb->lens + cvectors[book].len, 0, cb->nentries - cvectors[book].len);
 

         if (cb->lookup) {

             vals = cb_lookup_vals(cb->lookup, cb->ndimensions, cb->nentries);

             cb->quantlist = av_malloc_array(vals, sizeof(int));

             if (!cb->quantlist)
                 return AVERROR(ENOMEM);

             for (i = 0; i < vals; i++)
                 cb->quantlist[i] = cvectors[book].quant[i];

         } else {
             cb->quantlist = NULL;
         }

         if ((ret = ready_codebook(cb)) < 0)
             return ret;

     }

     venc->nfloors = 1;

     venc->floors  = av_malloc(sizeof(vorbis_enc_floor) * venc->nfloors);

     if (!venc->floors)
         return AVERROR(ENOMEM);

     // just 1 floor
     fc = &venc->floors[0];

     fc->partitions         = NUM_FLOOR_PARTITIONS;

     fc->partition_to_class = av_malloc(sizeof(int) * fc->partitions);

     if (!fc->partition_to_class)
         return AVERROR(ENOMEM);

     fc->nclasses           = 0;

     for (i = 0; i < fc->partitions; i++) {

         static const int a[] = {0, 1, 2, 2, 3, 3, 4, 4};

         fc->partition_to_class[i] = a[i];
         fc->nclasses = FFMAX(fc->nclasses, fc->partition_to_class[i]);
     }
     fc->nclasses++;

     fc->classes = av_malloc_array(fc->nclasses, sizeof(vorbis_enc_floor_class));

     if (!fc->classes)
         return AVERROR(ENOMEM);

     for (i = 0; i < fc->nclasses; i++) {

         vorbis_enc_floor_class * c = &fc->classes[i];

         int j, books;

         c->dim        = floor_classes[i].dim;
         c->subclass   = floor_classes[i].subclass;

         c->masterbook = floor_classes[i].masterbook;

         books         = (1 << c->subclass);

         c->books      = av_malloc_array(books, sizeof(int));

         if (!c->books)
             return AVERROR(ENOMEM);

         for (j = 0; j < books; j++)
             c->books[j] = floor_classes[i].nbooks[j];

     }

     fc->multiplier = 2;

     fc->rangebits  = venc->log2_blocksize[0] - 1;

 
     fc->values = 2;
     for (i = 0; i < fc->partitions; i++)
         fc->values += fc->classes[fc->partition_to_class[i]].dim;
 

     fc->list = av_malloc_array(fc->values, sizeof(vorbis_floor1_entry));

     if (!fc->list)
         return AVERROR(ENOMEM);

     fc->list[0].x = 0;
     fc->list[1].x = 1 << fc->rangebits;

     for (i = 2; i < fc->values; i++) {

         static const int a[] = {
              93, 23,372,  6, 46,186,750, 14, 33, 65,
             130,260,556,  3, 10, 18, 28, 39, 55, 79,
             111,158,220,312,464,650,850
         };

         fc->list[i].x = a[i - 2];

     }

     if (ff_vorbis_ready_floor1_list(avctx, fc->list, fc->values))

         return AVERROR_BUG;

 
     venc->nresidues = 1;

     venc->residues  = av_malloc(sizeof(vorbis_enc_residue) * venc->nresidues);

     if (!venc->residues)
         return AVERROR(ENOMEM);

     // single residue
     rc = &venc->residues[0];

     rc->type            = 2;
     rc->begin           = 0;
     rc->end             = 1600;
     rc->partition_size  = 32;

     rc->classifications = 10;

     rc->classbook       = 15;
     rc->books           = av_malloc(sizeof(*rc->books) * rc->classifications);

     if (!rc->books)
         return AVERROR(ENOMEM);

     {
         static const int8_t a[10][8] = {

             { -1, -1, -1, -1, -1, -1, -1, -1, },
             { -1, -1, 16, -1, -1, -1, -1, -1, },
             { -1, -1, 17, -1, -1, -1, -1, -1, },
             { -1, -1, 18, -1, -1, -1, -1, -1, },
             { -1, -1, 19, -1, -1, -1, -1, -1, },
             { -1, -1, 20, -1, -1, -1, -1, -1, },
             { -1, -1, 21, -1, -1, -1, -1, -1, },
             { 22, 23, -1, -1, -1, -1, -1, -1, },
             { 24, 25, -1, -1, -1, -1, -1, -1, },
             { 26, 27, 28, -1, -1, -1, -1, -1, },
         };

         memcpy(rc->books, a, sizeof a);

     }

     if ((ret = ready_residue(rc, venc)) < 0)
         return ret;

     venc->nmappings = 1;

     venc->mappings  = av_malloc(sizeof(vorbis_enc_mapping) * venc->nmappings);

     if (!venc->mappings)
         return AVERROR(ENOMEM);

     // single mapping
     mc = &venc->mappings[0];
     mc->submaps = 1;

     mc->mux     = av_malloc(sizeof(int) * venc->channels);

     if (!mc->mux)
         return AVERROR(ENOMEM);

     for (i = 0; i < venc->channels; i++)
         mc->mux[i] = 0;

     mc->floor   = av_malloc(sizeof(int) * mc->submaps);

     mc->residue = av_malloc(sizeof(int) * mc->submaps);

     if (!mc->floor || !mc->residue)
         return AVERROR(ENOMEM);

     for (i = 0; i < mc->submaps; i++) {

         mc->floor[i]   = 0;

         mc->residue[i] = 0;
     }

     mc->coupling_steps = venc->channels == 2 ? 1 : 0;

     mc->magnitude      = av_malloc(sizeof(int) * mc->coupling_steps);
     mc->angle          = av_malloc(sizeof(int) * mc->coupling_steps);

     if (!mc->magnitude || !mc->angle)
         return AVERROR(ENOMEM);

     if (mc->coupling_steps) {
         mc->magnitude[0] = 0;

         mc->angle[0]     = 1;

     }

     venc->nmodes = 1;

     venc->modes  = av_malloc(sizeof(vorbis_enc_mode) * venc->nmodes);

     if (!venc->modes)
         return AVERROR(ENOMEM);

 
     // single mode
     venc->modes[0].blockflag = 0;

     venc->modes[0].mapping   = 0;

     venc->have_saved = 0;

     venc->saved      = av_malloc_array(sizeof(float) * venc->channels, (1 << venc->log2_blocksize[1]) / 2);
     venc->samples    = av_malloc_array(sizeof(float) * venc->channels, (1 << venc->log2_blocksize[1]));
     venc->floor      = av_malloc_array(sizeof(float) * venc->channels, (1 << venc->log2_blocksize[1]) / 2);
     venc->coeffs     = av_malloc_array(sizeof(float) * venc->channels, (1 << venc->log2_blocksize[1]) / 2);

     if (!venc->saved || !venc->samples || !venc->floor || !venc->coeffs)
         return AVERROR(ENOMEM);

     venc->win[0] = ff_vorbis_vwin[venc->log2_blocksize[0] - 6];
     venc->win[1] = ff_vorbis_vwin[venc->log2_blocksize[1] - 6];

     if ((ret = ff_mdct_init(&venc->mdct[0], venc->log2_blocksize[0], 0, 1.0)) < 0)
         return ret;
     if ((ret = ff_mdct_init(&venc->mdct[1], venc->log2_blocksize[1], 0, 1.0)) < 0)
         return ret;
 
     return 0;

 }
 

 static void put_float(PutBitContext *pb, float f)

 {

     int exp, mant;
     uint32_t res = 0;
     mant = (int)ldexp(frexp(f, &exp), 20);
     exp += 788 - 20;

     if (mant < 0) {

         res |= (1U << 31);

         mant = -mant;
     }

     res |= mant | (exp << 21);

     put_bits32(pb, res);

 }
 

 static void put_codebook_header(PutBitContext *pb, vorbis_enc_codebook *cb)

 {

     int i;
     int ordered = 0;
 
     put_bits(pb, 24, 0x564342); //magic

     put_bits(pb, 16, cb->ndimensions);

     put_bits(pb, 24, cb->nentries);
 

     for (i = 1; i < cb->nentries; i++)

         if (cb->lens[i] < cb->lens[i-1])
             break;

     if (i == cb->nentries)
         ordered = 1;

 
     put_bits(pb, 1, ordered);
     if (ordered) {

         int len = cb->lens[0];

         put_bits(pb, 5, len - 1);

         i = 0;
         while (i < cb->nentries) {

             int j;

             for (j = 0; j+i < cb->nentries; j++)

                 if (cb->lens[j+i] != len)
                     break;

             put_bits(pb, ilog(cb->nentries - i), j);

             i += j;
             len++;
         }
     } else {
         int sparse = 0;

         for (i = 0; i < cb->nentries; i++)

             if (!cb->lens[i])
                 break;

         if (i != cb->nentries)
             sparse = 1;

         put_bits(pb, 1, sparse);
 
         for (i = 0; i < cb->nentries; i++) {

             if (sparse)
                 put_bits(pb, 1, !!cb->lens[i]);
             if (cb->lens[i])
                 put_bits(pb, 5, cb->lens[i] - 1);

         }
     }
 
     put_bits(pb, 4, cb->lookup);
     if (cb->lookup) {

         int tmp  = cb_lookup_vals(cb->lookup, cb->ndimensions, cb->nentries);

         int bits = ilog(cb->quantlist[0]);

         for (i = 1; i < tmp; i++)
             bits = FFMAX(bits, ilog(cb->quantlist[i]));

         put_float(pb, cb->min);
         put_float(pb, cb->delta);

         put_bits(pb, 4, bits - 1);
         put_bits(pb, 1, cb->seq_p);

         for (i = 0; i < tmp; i++)
             put_bits(pb, bits, cb->quantlist[i]);

     }
 }
 

 static void put_floor_header(PutBitContext *pb, vorbis_enc_floor *fc)

 {

     int i;
 
     put_bits(pb, 16, 1); // type, only floor1 is supported
 
     put_bits(pb, 5, fc->partitions);
 

     for (i = 0; i < fc->partitions; i++)
         put_bits(pb, 4, fc->partition_to_class[i]);

 
     for (i = 0; i < fc->nclasses; i++) {
         int j, books;
 
         put_bits(pb, 3, fc->classes[i].dim - 1);
         put_bits(pb, 2, fc->classes[i].subclass);
 

         if (fc->classes[i].subclass)
             put_bits(pb, 8, fc->classes[i].masterbook);

 
         books = (1 << fc->classes[i].subclass);
 

         for (j = 0; j < books; j++)
             put_bits(pb, 8, fc->classes[i].books[j] + 1);

     }
 
     put_bits(pb, 2, fc->multiplier - 1);
     put_bits(pb, 4, fc->rangebits);
 

     for (i = 2; i < fc->values; i++)
         put_bits(pb, fc->rangebits, fc->list[i].x);

 }
 

 static void put_residue_header(PutBitContext *pb, vorbis_enc_residue *rc)

 {

     int i;
 
     put_bits(pb, 16, rc->type);
 
     put_bits(pb, 24, rc->begin);
     put_bits(pb, 24, rc->end);
     put_bits(pb, 24, rc->partition_size - 1);

     put_bits(pb, 6, rc->classifications - 1);

     put_bits(pb, 8, rc->classbook);
 
     for (i = 0; i < rc->classifications; i++) {
         int j, tmp = 0;

         for (j = 0; j < 8; j++)
             tmp |= (rc->books[i][j] != -1) << j;

 
         put_bits(pb, 3, tmp & 7);
         put_bits(pb, 1, tmp > 7);
 

         if (tmp > 7)
             put_bits(pb, 5, tmp >> 3);

     }
 
     for (i = 0; i < rc->classifications; i++) {
         int j;
         for (j = 0; j < 8; j++)

             if (rc->books[i][j] != -1)

                 put_bits(pb, 8, rc->books[i][j]);
     }

 }
 

 static int put_main_header(vorbis_enc_context *venc, uint8_t **out)

 {

     int i;

     PutBitContext pb;
     int len, hlens[3];

     int buffer_len = 50000;
     uint8_t *buffer = av_mallocz(buffer_len), *p = buffer;
     if (!buffer)
         return AVERROR(ENOMEM);

 
     // identification header
     init_put_bits(&pb, p, buffer_len);
     put_bits(&pb, 8, 1); //magic

     for (i = 0; "vorbis"[i]; i++)
         put_bits(&pb, 8, "vorbis"[i]);

     put_bits32(&pb, 0); // version

     put_bits(&pb,  8, venc->channels);

     put_bits32(&pb, venc->sample_rate);
     put_bits32(&pb, 0); // bitrate
     put_bits32(&pb, 0); // bitrate
     put_bits32(&pb, 0); // bitrate

     put_bits(&pb,  4, venc->log2_blocksize[0]);
     put_bits(&pb,  4, venc->log2_blocksize[1]);
     put_bits(&pb,  1, 1); // framing

 
     flush_put_bits(&pb);

     hlens[0] = put_bits_count(&pb) >> 3;

     buffer_len -= hlens[0];
     p += hlens[0];
 
     // comment header
     init_put_bits(&pb, p, buffer_len);
     put_bits(&pb, 8, 3); //magic

     for (i = 0; "vorbis"[i]; i++)
         put_bits(&pb, 8, "vorbis"[i]);

     put_bits32(&pb, 0); // vendor length TODO
     put_bits32(&pb, 0); // amount of comments

     put_bits(&pb,  1, 1); // framing

 
     flush_put_bits(&pb);

     hlens[1] = put_bits_count(&pb) >> 3;

     buffer_len -= hlens[1];
     p += hlens[1];
 
     // setup header
     init_put_bits(&pb, p, buffer_len);
     put_bits(&pb, 8, 5); //magic

     for (i = 0; "vorbis"[i]; i++)
         put_bits(&pb, 8, "vorbis"[i]);

 
     // codebooks
     put_bits(&pb, 8, venc->ncodebooks - 1);

     for (i = 0; i < venc->ncodebooks; i++)
         put_codebook_header(&pb, &venc->codebooks[i]);

     // time domain, reserved, zero

     put_bits(&pb,  6, 0);

     put_bits(&pb, 16, 0);
 
     // floors
     put_bits(&pb, 6, venc->nfloors - 1);

     for (i = 0; i < venc->nfloors; i++)
         put_floor_header(&pb, &venc->floors[i]);

 
     // residues
     put_bits(&pb, 6, venc->nresidues - 1);

     for (i = 0; i < venc->nresidues; i++)
         put_residue_header(&pb, &venc->residues[i]);

 
     // mappings
     put_bits(&pb, 6, venc->nmappings - 1);
     for (i = 0; i < venc->nmappings; i++) {

         vorbis_enc_mapping *mc = &venc->mappings[i];

         int j;
         put_bits(&pb, 16, 0); // mapping type
 
         put_bits(&pb, 1, mc->submaps > 1);

         if (mc->submaps > 1)
             put_bits(&pb, 4, mc->submaps - 1);

         put_bits(&pb, 1, !!mc->coupling_steps);
         if (mc->coupling_steps) {
             put_bits(&pb, 8, mc->coupling_steps - 1);
             for (j = 0; j < mc->coupling_steps; j++) {
                 put_bits(&pb, ilog(venc->channels - 1), mc->magnitude[j]);
                 put_bits(&pb, ilog(venc->channels - 1), mc->angle[j]);
             }
         }

 
         put_bits(&pb, 2, 0); // reserved
 

         if (mc->submaps > 1)
             for (j = 0; j < venc->channels; j++)
                 put_bits(&pb, 4, mc->mux[j]);

 
         for (j = 0; j < mc->submaps; j++) {
             put_bits(&pb, 8, 0); // reserved time configuration
             put_bits(&pb, 8, mc->floor[j]);
             put_bits(&pb, 8, mc->residue[j]);
         }

     }

     // modes
     put_bits(&pb, 6, venc->nmodes - 1);
     for (i = 0; i < venc->nmodes; i++) {
         put_bits(&pb, 1, venc->modes[i].blockflag);
         put_bits(&pb, 16, 0); // reserved window type
         put_bits(&pb, 16, 0); // reserved transform type
         put_bits(&pb, 8, venc->modes[i].mapping);
     }
 

     put_bits(&pb, 1, 1); // framing
 

     flush_put_bits(&pb);

     hlens[2] = put_bits_count(&pb) >> 3;

 
     len = hlens[0] + hlens[1] + hlens[2];
     p = *out = av_mallocz(64 + len + len/255);

     if (!p)
         return AVERROR(ENOMEM);

 
     *p++ = 2;
     p += av_xiphlacing(p, hlens[0]);
     p += av_xiphlacing(p, hlens[1]);
     buffer_len = 0;
     for (i = 0; i < 3; i++) {
         memcpy(p, buffer + buffer_len, hlens[i]);
         p += hlens[i];
         buffer_len += hlens[i];
     }

     av_freep(&buffer);

     return p - *out;

 }
 

 static float get_floor_average(vorbis_enc_floor * fc, float *coeffs, int i)

 {

     int begin = fc->list[fc->list[FFMAX(i-1, 0)].sort].x;
     int end   = fc->list[fc->list[FFMIN(i+1, fc->values - 1)].sort].x;
     int j;
     float average = 0;
 

     for (j = begin; j < end; j++)
         average += fabs(coeffs[j]);

     return average / (end - begin);
 }
 

 static void floor_fit(vorbis_enc_context *venc, vorbis_enc_floor *fc,

                       float *coeffs, uint16_t *posts, int samples)

 {

     int range = 255 / fc->multiplier + 1;
     int i;

     float tot_average = 0.0;

     float averages[MAX_FLOOR_VALUES];

     for (i = 0; i < fc->values; i++) {

         averages[i] = get_floor_average(fc, coeffs, i);
         tot_average += averages[i];
     }

     tot_average /= fc->values;

     tot_average /= venc->quality;

     for (i = 0; i < fc->values; i++) {

         int position  = fc->list[fc->list[i].sort].x;

         float average = averages[i];

         int j;
 

         average = sqrt(tot_average * average) * pow(1.25f, position*0.005f); // MAGIC!

         for (j = 0; j < range - 1; j++)

             if (ff_vorbis_floor1_inverse_db_table[j * fc->multiplier] > average)
                 break;

         posts[fc->list[i].sort] = j;
     }
 }
 

 static int render_point(int x0, int y0, int x1, int y1, int x)
 {

     return y0 +  (x - x0) * (y1 - y0) / (x1 - x0);
 }
 

 static int floor_encode(vorbis_enc_context *venc, vorbis_enc_floor *fc,
                         PutBitContext *pb, uint16_t *posts,
                         float *floor, int samples)

 {

     int range = 255 / fc->multiplier + 1;

     int coded[MAX_FLOOR_VALUES]; // first 2 values are unused

     int i, counter;
 

     if (pb->size_in_bits - put_bits_count(pb) < 1 + 2 * ilog(range - 1))
         return AVERROR(EINVAL);

     put_bits(pb, 1, 1); // non zero

     put_bits(pb, ilog(range - 1), posts[0]);
     put_bits(pb, ilog(range - 1), posts[1]);

     coded[0] = coded[1] = 1;

 
     for (i = 2; i < fc->values; i++) {
         int predicted = render_point(fc->list[fc->list[i].low].x,
                                      posts[fc->list[i].low],
                                      fc->list[fc->list[i].high].x,
                                      posts[fc->list[i].high],
                                      fc->list[i].x);

         int highroom = range - predicted;

         int lowroom = predicted;
         int room = FFMIN(highroom, lowroom);
         if (predicted == posts[i]) {
             coded[i] = 0; // must be used later as flag!
             continue;

         } else {

             if (!coded[fc->list[i].low ])
                 coded[fc->list[i].low ] = -1;
             if (!coded[fc->list[i].high])
                 coded[fc->list[i].high] = -1;

         }
         if (posts[i] > predicted) {

             if (posts[i] - predicted > room)
                 coded[i] = posts[i] - predicted + lowroom;
             else
                 coded[i] = (posts[i] - predicted) << 1;

         } else {

             if (predicted - posts[i] > room)
                 coded[i] = predicted - posts[i] + highroom - 1;
             else
                 coded[i] = ((predicted - posts[i]) << 1) - 1;

         }
     }
 
     counter = 2;
     for (i = 0; i < fc->partitions; i++) {

         vorbis_enc_floor_class * c = &fc->classes[fc->partition_to_class[i]];

         int k, cval = 0, csub = 1<<c->subclass;
         if (c->subclass) {

             vorbis_enc_codebook * book = &venc->codebooks[c->masterbook];

             int cshift = 0;
             for (k = 0; k < c->dim; k++) {
                 int l;
                 for (l = 0; l < csub; l++) {
                     int maxval = 1;

                     if (c->books[l] != -1)
                         maxval = venc->codebooks[c->books[l]].nentries;

                     // coded could be -1, but this still works, cause that is 0

                     if (coded[counter + k] < maxval)
                         break;

                 }
                 assert(l != csub);

                 cval   |= l << cshift;

                 cshift += c->subclass;
             }

             if (put_codeword(pb, book, cval))
                 return AVERROR(EINVAL);

         }

         for (k = 0; k < c->dim; k++) {

             int book  = c->books[cval & (csub-1)];

             int entry = coded[counter++];

             cval >>= c->subclass;

             if (book == -1)
                 continue;
             if (entry == -1)
                 entry = 0;

             if (put_codeword(pb, &venc->codebooks[book], entry))
                 return AVERROR(EINVAL);

         }
     }
 

     ff_vorbis_floor1_render_list(fc->list, fc->values, posts, coded,
                                  fc->multiplier, floor, samples);

 
     return 0;

 }
 

 static float *put_vector(vorbis_enc_codebook *book, PutBitContext *pb,
                          float *num)

 {

     int i, entry = -1;
     float distance = FLT_MAX;

     assert(book->dimensions);

     for (i = 0; i < book->nentries; i++) {

         float * vec = book->dimensions + i * book->ndimensions, d = book->pow2[i];

         int j;

         if (!book->lens[i])
             continue;

         for (j = 0; j < book->ndimensions; j++)

             d -= vec[j] * num[j];

         if (distance > d) {

             entry    = i;

             distance = d;
         }
     }

     if (put_codeword(pb, book, entry))
         return NULL;

     return &book->dimensions[entry * book->ndimensions];

 }

 static int residue_encode(vorbis_enc_context *venc, vorbis_enc_residue *rc,
                           PutBitContext *pb, float *coeffs, int samples,
                           int real_ch)

 {

     int pass, i, j, p, k;

     int psize      = rc->partition_size;

     int partitions = (rc->end - rc->begin) / psize;

     int channels   = (rc->type == 2) ? 1 : real_ch;

     int classes[MAX_CHANNELS][NUM_RESIDUE_PARTITIONS];

     int classwords = venc->codebooks[rc->classbook].ndimensions;

     av_assert0(rc->type == 2);
     av_assert0(real_ch == 2);

     for (p = 0; p < partitions; p++) {

         float max1 = 0.0, max2 = 0.0;

         int s = rc->begin + p * psize;
         for (k = s; k < s + psize; k += 2) {

             max1 = FFMAX(max1, fabs(coeffs[          k / real_ch]));
             max2 = FFMAX(max2, fabs(coeffs[samples + k / real_ch]));

         }
 

         for (i = 0; i < rc->classifications - 1; i++)
             if (max1 < rc->maxes[i][0] && max2 < rc->maxes[i][1])
                 break;

         classes[0][p] = i;
     }
 

     for (pass = 0; pass < 8; pass++) {
         p = 0;
         while (p < partitions) {

             if (pass == 0)
                 for (j = 0; j < channels; j++) {

                     vorbis_enc_codebook * book = &venc->codebooks[rc->classbook];

                     int entry = 0;
                     for (i = 0; i < classwords; i++) {
                         entry *= rc->classifications;
                         entry += classes[j][p + i];
                     }

                     if (put_codeword(pb, book, entry))
                         return AVERROR(EINVAL);

                 }
             for (i = 0; i < classwords && p < partitions; i++, p++) {
                 for (j = 0; j < channels; j++) {
                     int nbook = rc->books[classes[j][p]][pass];

                     vorbis_enc_codebook * book = &venc->codebooks[nbook];

                     float *buf = coeffs + samples*j + rc->begin + p*psize;

                     if (nbook == -1)
                         continue;

                     assert(rc->type == 0 || rc->type == 2);

                     assert(!(psize % book->ndimensions));

                     if (rc->type == 0) {

                         for (k = 0; k < psize; k += book->ndimensions) {

                             int l;

                             float *a = put_vector(book, pb, &buf[k]);
                             if (!a)
                                 return AVERROR(EINVAL);

                             for (l = 0; l < book->ndimensions; l++)

                                 buf[k + l] -= a[l];

                         }

                     } else {

                         int s = rc->begin + p * psize, a1, b1;
                         a1 = (s % real_ch) * samples;
                         b1 =  s / real_ch;

                         s  = real_ch * samples;

                         for (k = 0; k < psize; k += book->ndimensions) {

                             int dim, a2 = a1, b2 = b1;

                             float vec[MAX_CODEBOOK_DIM], *pv = vec;

                             for (dim = book->ndimensions; dim--; ) {

                                 *pv++ = coeffs[a2 + b2];

                                 if ((a2 += samples) == s) {

                                     a2 = 0;

                                     b2++;
                                 }

                             }
                             pv = put_vector(book, pb, vec);

                             if (!pv)
                                 return AVERROR(EINVAL);

                             for (dim = book->ndimensions; dim--; ) {

                                 coeffs[a1 + b1] -= *pv++;

                                 if ((a1 += samples) == s) {

                                     a1 = 0;

                                     b1++;
                                 }

                             }

                         }
                     }

                 }
             }
         }
     }

     return 0;

 }
 

 static int apply_window_and_mdct(vorbis_enc_context *venc,
                                  float **audio, int samples)

 {

     int i, channel;

     const float * win = venc->win[0];

     int window_len = 1 << (venc->log2_blocksize[0] - 1);

     float n = (float)(1 << venc->log2_blocksize[0]) / 4.0;

     // FIXME use dsp
 

     if (!venc->have_saved && !samples)
         return 0;

     if (venc->have_saved) {

         for (channel = 0; channel < venc->channels; channel++)

             memcpy(venc->samples + channel * window_len * 2,
                    venc->saved + channel * window_len, sizeof(float) * window_len);
     } else {

         for (channel = 0; channel < venc->channels; channel++)

             memset(venc->samples + channel * window_len * 2, 0,
                    sizeof(float) * window_len);
     }

 
     if (samples) {
         for (channel = 0; channel < venc->channels; channel++) {

             float * offset = venc->samples + channel*window_len*2 + window_len;

             for (i = 0; i < samples; i++)
                 offset[i] = audio[channel][i] / n * win[window_len - i - 1];

         }
     } else {

         for (channel = 0; channel < venc->channels; channel++)

             memset(venc->samples + channel * window_len * 2 + window_len,
                    0, sizeof(float) * window_len);

     }
 

     for (channel = 0; channel < venc->channels; channel++)

         venc->mdct[0].mdct_calc(&venc->mdct[0], venc->coeffs + channel * window_len,

                      venc->samples + channel * window_len * 2);

 
     if (samples) {
         for (channel = 0; channel < venc->channels; channel++) {

             float *offset = venc->saved + channel * window_len;

             for (i = 0; i < samples; i++)
                 offset[i] = audio[channel][i] / n * win[i];

         }
         venc->have_saved = 1;
     } else {
         venc->have_saved = 0;
     }
     return 1;
 }

 static int vorbis_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,

                                const AVFrame *frame, int *got_packet_ptr)

 {

     vorbis_enc_context *venc = avctx->priv_data;

     float **audio = frame ? (float **)frame->extended_data : NULL;

     int samples = frame ? frame->nb_samples : 0;

     vorbis_enc_mode *mode;
     vorbis_enc_mapping *mapping;

     PutBitContext pb;

     int i, ret;

     if (!apply_window_and_mdct(venc, audio, samples))
         return 0;

     samples = 1 << (venc->log2_blocksize[0] - 1);

     if ((ret = ff_alloc_packet2(avctx, avpkt, 8192, 0)) < 0)

         return ret;
 
     init_put_bits(&pb, avpkt->data, avpkt->size);

     if (pb.size_in_bits - put_bits_count(&pb) < 1 + ilog(venc->nmodes - 1)) {

         av_log(avctx, AV_LOG_ERROR, "output buffer is too small\n");

         return AVERROR(EINVAL);
     }
 

     put_bits(&pb, 1, 0); // magic bit
 
     put_bits(&pb, ilog(venc->nmodes - 1), 0); // 0 bits, the mode
 

     mode    = &venc->modes[0];

     mapping = &venc->mappings[mode->mapping];
     if (mode->blockflag) {
         put_bits(&pb, 1, 0);
         put_bits(&pb, 1, 0);
     }
 
     for (i = 0; i < venc->channels; i++) {

         vorbis_enc_floor *fc = &venc->floors[mapping->floor[mapping->mux[i]]];

         uint16_t posts[MAX_FLOOR_VALUES];

         floor_fit(venc, fc, &venc->coeffs[i * samples], posts, samples);

         if (floor_encode(venc, fc, &pb, posts, &venc->floor[i * samples], samples)) {

             av_log(avctx, AV_LOG_ERROR, "output buffer is too small\n");

             return AVERROR(EINVAL);
         }

     }

     for (i = 0; i < venc->channels * samples; i++)

         venc->coeffs[i] /= venc->floor[i];

     for (i = 0; i < mapping->coupling_steps; i++) {

         float *mag = venc->coeffs + mapping->magnitude[i] * samples;
         float *ang = venc->coeffs + mapping->angle[i]     * samples;

         int j;
         for (j = 0; j < samples; j++) {
             float a = ang[j];

             ang[j] -= mag[j];

             if (mag[j] > 0)
                 ang[j] = -ang[j];
             if (ang[j] < 0)
                 mag[j] = a;

         }
     }
 

     if (residue_encode(venc, &venc->residues[mapping->residue[mapping->mux[0]]],
                        &pb, venc->coeffs, samples, venc->channels)) {

         av_log(avctx, AV_LOG_ERROR, "output buffer is too small\n");

         return AVERROR(EINVAL);
     }

     flush_put_bits(&pb);

     avpkt->size = put_bits_count(&pb) >> 3;
 

     avpkt->duration = ff_samples_to_time_base(avctx, avctx->frame_size);

     if (frame) {

         if (frame->pts != AV_NOPTS_VALUE)

             avpkt->pts = ff_samples_to_time_base(avctx, frame->pts);

     } else {

         avpkt->pts = venc->next_pts;

     }

     if (avpkt->pts != AV_NOPTS_VALUE)
         venc->next_pts = avpkt->pts + avpkt->duration;
 
     *got_packet_ptr = 1;
     return 0;

 }
 
 

 static av_cold int vorbis_encode_close(AVCodecContext *avctx)

 {

     vorbis_enc_context *venc = avctx->priv_data;

     int i;
 

     if (venc->codebooks)
         for (i = 0; i < venc->ncodebooks; i++) {
             av_freep(&venc->codebooks[i].lens);
             av_freep(&venc->codebooks[i].codewords);
             av_freep(&venc->codebooks[i].quantlist);

             av_freep(&venc->codebooks[i].dimensions);

             av_freep(&venc->codebooks[i].pow2);
         }

     av_freep(&venc->codebooks);
 

     if (venc->floors)
         for (i = 0; i < venc->nfloors; i++) {
             int j;
             if (venc->floors[i].classes)
                 for (j = 0; j < venc->floors[i].nclasses; j++)
                     av_freep(&venc->floors[i].classes[j].books);

             av_freep(&venc->floors[i].classes);

             av_freep(&venc->floors[i].partition_to_class);
             av_freep(&venc->floors[i].list);
         }

     av_freep(&venc->floors);
 

     if (venc->residues)
         for (i = 0; i < venc->nresidues; i++) {
             av_freep(&venc->residues[i].books);
             av_freep(&venc->residues[i].maxes);
         }

     av_freep(&venc->residues);
 

     if (venc->mappings)
         for (i = 0; i < venc->nmappings; i++) {
             av_freep(&venc->mappings[i].mux);
             av_freep(&venc->mappings[i].floor);
             av_freep(&venc->mappings[i].residue);

             av_freep(&venc->mappings[i].magnitude);
             av_freep(&venc->mappings[i].angle);

         }

     av_freep(&venc->mappings);
 
     av_freep(&venc->modes);

     av_freep(&venc->saved);
     av_freep(&venc->samples);
     av_freep(&venc->floor);
     av_freep(&venc->coeffs);
 
     ff_mdct_end(&venc->mdct[0]);
     ff_mdct_end(&venc->mdct[1]);
 

     av_freep(&avctx->extradata);

 
     return 0 ;
 }
 

 static av_cold int vorbis_encode_init(AVCodecContext *avctx)

 {

     vorbis_enc_context *venc = avctx->priv_data;

     int ret;
 

     if (avctx->channels != 2) {

         av_log(avctx, AV_LOG_ERROR, "Current FFmpeg Vorbis encoder only supports 2 channels.\n");

         return -1;
     }
 

     if ((ret = create_vorbis_context(venc, avctx)) < 0)

         goto error;
 

     avctx->bit_rate = 0;

     if (avctx->flags & AV_CODEC_FLAG_QSCALE)

         venc->quality = avctx->global_quality / (float)FF_QP2LAMBDA;

     else

         venc->quality = 8;

     venc->quality *= venc->quality;
 

     if ((ret = put_main_header(venc, (uint8_t**)&avctx->extradata)) < 0)

         goto error;

     avctx->extradata_size = ret;

     avctx->frame_size = 1 << (venc->log2_blocksize[0] - 1);

 
     return 0;
 error:

     vorbis_encode_close(avctx);

     return ret;
 }
 

 AVCodec ff_vorbis_encoder = {

     .name           = "vorbis",

     .long_name      = NULL_IF_CONFIG_SMALL("Vorbis"),

     .type           = AVMEDIA_TYPE_AUDIO,

     .id             = AV_CODEC_ID_VORBIS,

     .priv_data_size = sizeof(vorbis_enc_context),
     .init           = vorbis_encode_init,

     .encode2        = vorbis_encode_frame,

     .close          = vorbis_encode_close,

     .capabilities   = AV_CODEC_CAP_DELAY | AV_CODEC_CAP_EXPERIMENTAL,

     .sample_fmts    = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_FLTP,

                                                      AV_SAMPLE_FMT_NONE },

 };