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libavcodec/vorbis_enc.c

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00001 /*
00002  * copyright (c) 2006 Oded Shimon <ods15@ods15.dyndns.org>
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * FFmpeg is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with FFmpeg; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 
00027 #include <float.h>
00028 #include "avcodec.h"
00029 #include "dsputil.h"
00030 #include "vorbis.h"
00031 #include "vorbis_enc_data.h"
00032 
00033 #define BITSTREAM_WRITER_LE
00034 #include "bitstream.h"
00035 
00036 #undef NDEBUG
00037 #include <assert.h>
00038 
00039 typedef struct {
00040     int nentries;
00041     uint8_t * lens;
00042     uint32_t * codewords;
00043     int ndimentions;
00044     float min;
00045     float delta;
00046     int seq_p;
00047     int lookup;
00048     int * quantlist;
00049     float * dimentions;
00050     float * pow2;
00051 } vorbis_enc_codebook;
00052 
00053 typedef struct {
00054     int dim;
00055     int subclass;
00056     int masterbook;
00057     int * books;
00058 } vorbis_enc_floor_class;
00059 
00060 typedef struct {
00061     int partitions;
00062     int * partition_to_class;
00063     int nclasses;
00064     vorbis_enc_floor_class * classes;
00065     int multiplier;
00066     int rangebits;
00067     int values;
00068     vorbis_floor1_entry * list;
00069 } vorbis_enc_floor;
00070 
00071 typedef struct {
00072     int type;
00073     int begin;
00074     int end;
00075     int partition_size;
00076     int classifications;
00077     int classbook;
00078     int8_t (*books)[8];
00079     float (*maxes)[2];
00080 } vorbis_enc_residue;
00081 
00082 typedef struct {
00083     int submaps;
00084     int * mux;
00085     int * floor;
00086     int * residue;
00087     int coupling_steps;
00088     int * magnitude;
00089     int * angle;
00090 } vorbis_enc_mapping;
00091 
00092 typedef struct {
00093     int blockflag;
00094     int mapping;
00095 } vorbis_enc_mode;
00096 
00097 typedef struct {
00098     int channels;
00099     int sample_rate;
00100     int log2_blocksize[2];
00101     MDCTContext mdct[2];
00102     const float * win[2];
00103     int have_saved;
00104     float * saved;
00105     float * samples;
00106     float * floor; // also used for tmp values for mdct
00107     float * coeffs; // also used for residue after floor
00108     float quality;
00109 
00110     int ncodebooks;
00111     vorbis_enc_codebook * codebooks;
00112 
00113     int nfloors;
00114     vorbis_enc_floor * floors;
00115 
00116     int nresidues;
00117     vorbis_enc_residue * residues;
00118 
00119     int nmappings;
00120     vorbis_enc_mapping * mappings;
00121 
00122     int nmodes;
00123     vorbis_enc_mode * modes;
00124 
00125     int64_t sample_count;
00126 } vorbis_enc_context;
00127 
00128 static inline void put_codeword(PutBitContext * pb, vorbis_enc_codebook * cb, int entry) {
00129     assert(entry >= 0);
00130     assert(entry < cb->nentries);
00131     assert(cb->lens[entry]);
00132     put_bits(pb, cb->lens[entry], cb->codewords[entry]);
00133 }
00134 
00135 static int cb_lookup_vals(int lookup, int dimentions, int entries) {
00136     if      (lookup == 1) return ff_vorbis_nth_root(entries, dimentions);
00137     else if (lookup == 2) return dimentions * entries;
00138     return 0;
00139 }
00140 
00141 static void ready_codebook(vorbis_enc_codebook * cb) {
00142     int i;
00143 
00144     ff_vorbis_len2vlc(cb->lens, cb->codewords, cb->nentries);
00145 
00146     if (!cb->lookup)
00147         cb->pow2 = cb->dimentions = NULL;
00148     else {
00149         int vals = cb_lookup_vals(cb->lookup, cb->ndimentions, cb->nentries);
00150         cb->dimentions = av_malloc(sizeof(float) * cb->nentries * cb->ndimentions);
00151         cb->pow2 = av_mallocz(sizeof(float) * cb->nentries);
00152         for (i = 0; i < cb->nentries; i++) {
00153             float last = 0;
00154             int j;
00155             int div = 1;
00156             for (j = 0; j < cb->ndimentions; j++) {
00157                 int off;
00158                 if (cb->lookup == 1)
00159                     off = (i / div) % vals; // lookup type 1
00160                 else
00161                     off = i * cb->ndimentions + j; // lookup type 2
00162 
00163                 cb->dimentions[i * cb->ndimentions + j] = last + cb->min + cb->quantlist[off] * cb->delta;
00164                 if (cb->seq_p)
00165                     last = cb->dimentions[i * cb->ndimentions + j];
00166                 cb->pow2[i] += cb->dimentions[i * cb->ndimentions + j]*cb->dimentions[i * cb->ndimentions + j];
00167                 div *= vals;
00168             }
00169             cb->pow2[i] /= 2.;
00170         }
00171     }
00172 }
00173 
00174 static void ready_residue(vorbis_enc_residue * rc, vorbis_enc_context * venc) {
00175     int i;
00176     assert(rc->type == 2);
00177     rc->maxes = av_mallocz(sizeof(float[2]) * rc->classifications);
00178     for (i = 0; i < rc->classifications; i++) {
00179         int j;
00180         vorbis_enc_codebook * cb;
00181         for (j = 0; j < 8; j++)
00182             if (rc->books[i][j] != -1) break;
00183         if (j == 8) continue; // zero
00184         cb = &venc->codebooks[rc->books[i][j]];
00185         assert(cb->ndimentions >= 2);
00186         assert(cb->lookup);
00187 
00188         for (j = 0; j < cb->nentries; j++) {
00189             float a;
00190             if (!cb->lens[j]) continue;
00191             a = fabs(cb->dimentions[j * cb->ndimentions]);
00192             if (a > rc->maxes[i][0])
00193                 rc->maxes[i][0] = a;
00194             a = fabs(cb->dimentions[j * cb->ndimentions + 1]);
00195             if (a > rc->maxes[i][1])
00196                 rc->maxes[i][1] = a;
00197         }
00198     }
00199     // small bias
00200     for (i = 0; i < rc->classifications; i++) {
00201         rc->maxes[i][0] += 0.8;
00202         rc->maxes[i][1] += 0.8;
00203     }
00204 }
00205 
00206 static void create_vorbis_context(vorbis_enc_context * venc, AVCodecContext * avccontext) {
00207     vorbis_enc_floor * fc;
00208     vorbis_enc_residue * rc;
00209     vorbis_enc_mapping * mc;
00210     int i, book;
00211 
00212     venc->channels = avccontext->channels;
00213     venc->sample_rate = avccontext->sample_rate;
00214     venc->log2_blocksize[0] = venc->log2_blocksize[1] = 11;
00215 
00216     venc->ncodebooks = FF_ARRAY_ELEMS(cvectors);
00217     venc->codebooks = av_malloc(sizeof(vorbis_enc_codebook) * venc->ncodebooks);
00218 
00219     // codebook 0..14 - floor1 book, values 0..255
00220     // codebook 15 residue masterbook
00221     // codebook 16..29 residue
00222     for (book = 0; book < venc->ncodebooks; book++) {
00223         vorbis_enc_codebook * cb = &venc->codebooks[book];
00224         int vals;
00225         cb->ndimentions = cvectors[book].dim;
00226         cb->nentries = cvectors[book].real_len;
00227         cb->min = cvectors[book].min;
00228         cb->delta = cvectors[book].delta;
00229         cb->lookup = cvectors[book].lookup;
00230         cb->seq_p = 0;
00231 
00232         cb->lens = av_malloc(sizeof(uint8_t) * cb->nentries);
00233         cb->codewords = av_malloc(sizeof(uint32_t) * cb->nentries);
00234         memcpy(cb->lens, cvectors[book].clens, cvectors[book].len);
00235         memset(cb->lens + cvectors[book].len, 0, cb->nentries - cvectors[book].len);
00236 
00237         if (cb->lookup) {
00238             vals = cb_lookup_vals(cb->lookup, cb->ndimentions, cb->nentries);
00239             cb->quantlist = av_malloc(sizeof(int) * vals);
00240             for (i = 0; i < vals; i++)
00241                 cb->quantlist[i] = cvectors[book].quant[i];
00242         } else {
00243             cb->quantlist = NULL;
00244         }
00245         ready_codebook(cb);
00246     }
00247 
00248     venc->nfloors = 1;
00249     venc->floors = av_malloc(sizeof(vorbis_enc_floor) * venc->nfloors);
00250 
00251     // just 1 floor
00252     fc = &venc->floors[0];
00253     fc->partitions = 8;
00254     fc->partition_to_class = av_malloc(sizeof(int) * fc->partitions);
00255     fc->nclasses = 0;
00256     for (i = 0; i < fc->partitions; i++) {
00257         static const int a[] = {0,1,2,2,3,3,4,4};
00258         fc->partition_to_class[i] = a[i];
00259         fc->nclasses = FFMAX(fc->nclasses, fc->partition_to_class[i]);
00260     }
00261     fc->nclasses++;
00262     fc->classes = av_malloc(sizeof(vorbis_enc_floor_class) * fc->nclasses);
00263     for (i = 0; i < fc->nclasses; i++) {
00264         vorbis_enc_floor_class * c = &fc->classes[i];
00265         int j, books;
00266         c->dim = floor_classes[i].dim;
00267         c->subclass = floor_classes[i].subclass;
00268         c->masterbook = floor_classes[i].masterbook;
00269         books = (1 << c->subclass);
00270         c->books = av_malloc(sizeof(int) * books);
00271         for (j = 0; j < books; j++)
00272             c->books[j] = floor_classes[i].nbooks[j];
00273     }
00274     fc->multiplier = 2;
00275     fc->rangebits = venc->log2_blocksize[0] - 1;
00276 
00277     fc->values = 2;
00278     for (i = 0; i < fc->partitions; i++)
00279         fc->values += fc->classes[fc->partition_to_class[i]].dim;
00280 
00281     fc->list = av_malloc(sizeof(vorbis_floor1_entry) * fc->values);
00282     fc->list[0].x = 0;
00283     fc->list[1].x = 1 << fc->rangebits;
00284     for (i = 2; i < fc->values; i++) {
00285         static const int a[] = {
00286              93, 23,372,  6, 46,186,750, 14, 33, 65,
00287             130,260,556,  3, 10, 18, 28, 39, 55, 79,
00288             111,158,220,312,464,650,850
00289         };
00290         fc->list[i].x = a[i - 2];
00291     }
00292     ff_vorbis_ready_floor1_list(fc->list, fc->values);
00293 
00294     venc->nresidues = 1;
00295     venc->residues = av_malloc(sizeof(vorbis_enc_residue) * venc->nresidues);
00296 
00297     // single residue
00298     rc = &venc->residues[0];
00299     rc->type = 2;
00300     rc->begin = 0;
00301     rc->end = 1600;
00302     rc->partition_size = 32;
00303     rc->classifications = 10;
00304     rc->classbook = 15;
00305     rc->books = av_malloc(sizeof(*rc->books) * rc->classifications);
00306     {
00307         static const int8_t a[10][8] = {
00308             { -1, -1, -1, -1, -1, -1, -1, -1, },
00309             { -1, -1, 16, -1, -1, -1, -1, -1, },
00310             { -1, -1, 17, -1, -1, -1, -1, -1, },
00311             { -1, -1, 18, -1, -1, -1, -1, -1, },
00312             { -1, -1, 19, -1, -1, -1, -1, -1, },
00313             { -1, -1, 20, -1, -1, -1, -1, -1, },
00314             { -1, -1, 21, -1, -1, -1, -1, -1, },
00315             { 22, 23, -1, -1, -1, -1, -1, -1, },
00316             { 24, 25, -1, -1, -1, -1, -1, -1, },
00317             { 26, 27, 28, -1, -1, -1, -1, -1, },
00318         };
00319         memcpy(rc->books, a, sizeof a);
00320     }
00321     ready_residue(rc, venc);
00322 
00323     venc->nmappings = 1;
00324     venc->mappings = av_malloc(sizeof(vorbis_enc_mapping) * venc->nmappings);
00325 
00326     // single mapping
00327     mc = &venc->mappings[0];
00328     mc->submaps = 1;
00329     mc->mux = av_malloc(sizeof(int) * venc->channels);
00330     for (i = 0; i < venc->channels; i++)
00331         mc->mux[i] = 0;
00332     mc->floor = av_malloc(sizeof(int) * mc->submaps);
00333     mc->residue = av_malloc(sizeof(int) * mc->submaps);
00334     for (i = 0; i < mc->submaps; i++) {
00335         mc->floor[i] = 0;
00336         mc->residue[i] = 0;
00337     }
00338     mc->coupling_steps = venc->channels == 2 ? 1 : 0;
00339     mc->magnitude = av_malloc(sizeof(int) * mc->coupling_steps);
00340     mc->angle = av_malloc(sizeof(int) * mc->coupling_steps);
00341     if (mc->coupling_steps) {
00342         mc->magnitude[0] = 0;
00343         mc->angle[0] = 1;
00344     }
00345 
00346     venc->nmodes = 1;
00347     venc->modes = av_malloc(sizeof(vorbis_enc_mode) * venc->nmodes);
00348 
00349     // single mode
00350     venc->modes[0].blockflag = 0;
00351     venc->modes[0].mapping = 0;
00352 
00353     venc->have_saved = 0;
00354     venc->saved = av_malloc(sizeof(float) * venc->channels * (1 << venc->log2_blocksize[1]) / 2);
00355     venc->samples = av_malloc(sizeof(float) * venc->channels * (1 << venc->log2_blocksize[1]));
00356     venc->floor = av_malloc(sizeof(float) * venc->channels * (1 << venc->log2_blocksize[1]) / 2);
00357     venc->coeffs = av_malloc(sizeof(float) * venc->channels * (1 << venc->log2_blocksize[1]) / 2);
00358 
00359     venc->win[0] = ff_vorbis_vwin[venc->log2_blocksize[0] - 6];
00360     venc->win[1] = ff_vorbis_vwin[venc->log2_blocksize[1] - 6];
00361 
00362     ff_mdct_init(&venc->mdct[0], venc->log2_blocksize[0], 0);
00363     ff_mdct_init(&venc->mdct[1], venc->log2_blocksize[1], 0);
00364 }
00365 
00366 static void put_float(PutBitContext * pb, float f) {
00367     int exp, mant;
00368     uint32_t res = 0;
00369     mant = (int)ldexp(frexp(f, &exp), 20);
00370     exp += 788 - 20;
00371     if (mant < 0) { res |= (1 << 31); mant = -mant; }
00372     res |= mant | (exp << 21);
00373     put_bits(pb, 32, res);
00374 }
00375 
00376 static void put_codebook_header(PutBitContext * pb, vorbis_enc_codebook * cb) {
00377     int i;
00378     int ordered = 0;
00379 
00380     put_bits(pb, 24, 0x564342); //magic
00381     put_bits(pb, 16, cb->ndimentions);
00382     put_bits(pb, 24, cb->nentries);
00383 
00384     for (i = 1; i < cb->nentries; i++)
00385         if (cb->lens[i] < cb->lens[i-1]) break;
00386     if (i == cb->nentries)
00387         ordered = 1;
00388 
00389     put_bits(pb, 1, ordered);
00390     if (ordered) {
00391         int len = cb->lens[0];
00392         put_bits(pb, 5, len - 1);
00393         i = 0;
00394         while (i < cb->nentries) {
00395             int j;
00396             for (j = 0; j+i < cb->nentries; j++)
00397                 if (cb->lens[j+i] != len) break;
00398             put_bits(pb, ilog(cb->nentries - i), j);
00399             i += j;
00400             len++;
00401         }
00402     } else {
00403         int sparse = 0;
00404         for (i = 0; i < cb->nentries; i++)
00405             if (!cb->lens[i]) break;
00406         if (i != cb->nentries)
00407             sparse = 1;
00408         put_bits(pb, 1, sparse);
00409 
00410         for (i = 0; i < cb->nentries; i++) {
00411             if (sparse) put_bits(pb, 1, !!cb->lens[i]);
00412             if (cb->lens[i]) put_bits(pb, 5, cb->lens[i] - 1);
00413         }
00414     }
00415 
00416     put_bits(pb, 4, cb->lookup);
00417     if (cb->lookup) {
00418         int tmp = cb_lookup_vals(cb->lookup, cb->ndimentions, cb->nentries);
00419         int bits = ilog(cb->quantlist[0]);
00420 
00421         for (i = 1; i < tmp; i++)
00422             bits = FFMAX(bits, ilog(cb->quantlist[i]));
00423 
00424         put_float(pb, cb->min);
00425         put_float(pb, cb->delta);
00426 
00427         put_bits(pb, 4, bits - 1);
00428         put_bits(pb, 1, cb->seq_p);
00429 
00430         for (i = 0; i < tmp; i++)
00431             put_bits(pb, bits, cb->quantlist[i]);
00432     }
00433 }
00434 
00435 static void put_floor_header(PutBitContext * pb, vorbis_enc_floor * fc) {
00436     int i;
00437 
00438     put_bits(pb, 16, 1); // type, only floor1 is supported
00439 
00440     put_bits(pb, 5, fc->partitions);
00441 
00442     for (i = 0; i < fc->partitions; i++)
00443         put_bits(pb, 4, fc->partition_to_class[i]);
00444 
00445     for (i = 0; i < fc->nclasses; i++) {
00446         int j, books;
00447 
00448         put_bits(pb, 3, fc->classes[i].dim - 1);
00449         put_bits(pb, 2, fc->classes[i].subclass);
00450 
00451         if (fc->classes[i].subclass)
00452             put_bits(pb, 8, fc->classes[i].masterbook);
00453 
00454         books = (1 << fc->classes[i].subclass);
00455 
00456         for (j = 0; j < books; j++)
00457             put_bits(pb, 8, fc->classes[i].books[j] + 1);
00458     }
00459 
00460     put_bits(pb, 2, fc->multiplier - 1);
00461     put_bits(pb, 4, fc->rangebits);
00462 
00463     for (i = 2; i < fc->values; i++)
00464         put_bits(pb, fc->rangebits, fc->list[i].x);
00465 }
00466 
00467 static void put_residue_header(PutBitContext * pb, vorbis_enc_residue * rc) {
00468     int i;
00469 
00470     put_bits(pb, 16, rc->type);
00471 
00472     put_bits(pb, 24, rc->begin);
00473     put_bits(pb, 24, rc->end);
00474     put_bits(pb, 24, rc->partition_size - 1);
00475     put_bits(pb, 6, rc->classifications - 1);
00476     put_bits(pb, 8, rc->classbook);
00477 
00478     for (i = 0; i < rc->classifications; i++) {
00479         int j, tmp = 0;
00480         for (j = 0; j < 8; j++)
00481             tmp |= (rc->books[i][j] != -1) << j;
00482 
00483         put_bits(pb, 3, tmp & 7);
00484         put_bits(pb, 1, tmp > 7);
00485 
00486         if (tmp > 7)
00487             put_bits(pb, 5, tmp >> 3);
00488     }
00489 
00490     for (i = 0; i < rc->classifications; i++) {
00491         int j;
00492         for (j = 0; j < 8; j++)
00493             if (rc->books[i][j] != -1)
00494                 put_bits(pb, 8, rc->books[i][j]);
00495     }
00496 }
00497 
00498 static int put_main_header(vorbis_enc_context * venc, uint8_t ** out) {
00499     int i;
00500     PutBitContext pb;
00501     uint8_t buffer[50000] = {0}, * p = buffer;
00502     int buffer_len = sizeof buffer;
00503     int len, hlens[3];
00504 
00505     // identification header
00506     init_put_bits(&pb, p, buffer_len);
00507     put_bits(&pb, 8, 1); //magic
00508     for (i = 0; "vorbis"[i]; i++)
00509         put_bits(&pb, 8, "vorbis"[i]);
00510     put_bits(&pb, 32, 0); // version
00511     put_bits(&pb, 8, venc->channels);
00512     put_bits(&pb, 32, venc->sample_rate);
00513     put_bits(&pb, 32, 0); // bitrate
00514     put_bits(&pb, 32, 0); // bitrate
00515     put_bits(&pb, 32, 0); // bitrate
00516     put_bits(&pb, 4, venc->log2_blocksize[0]);
00517     put_bits(&pb, 4, venc->log2_blocksize[1]);
00518     put_bits(&pb, 1, 1); // framing
00519 
00520     flush_put_bits(&pb);
00521     hlens[0] = (put_bits_count(&pb) + 7) / 8;
00522     buffer_len -= hlens[0];
00523     p += hlens[0];
00524 
00525     // comment header
00526     init_put_bits(&pb, p, buffer_len);
00527     put_bits(&pb, 8, 3); //magic
00528     for (i = 0; "vorbis"[i]; i++)
00529         put_bits(&pb, 8, "vorbis"[i]);
00530     put_bits(&pb, 32, 0); // vendor length TODO
00531     put_bits(&pb, 32, 0); // amount of comments
00532     put_bits(&pb, 1, 1); // framing
00533 
00534     flush_put_bits(&pb);
00535     hlens[1] = (put_bits_count(&pb) + 7) / 8;
00536     buffer_len -= hlens[1];
00537     p += hlens[1];
00538 
00539     // setup header
00540     init_put_bits(&pb, p, buffer_len);
00541     put_bits(&pb, 8, 5); //magic
00542     for (i = 0; "vorbis"[i]; i++)
00543         put_bits(&pb, 8, "vorbis"[i]);
00544 
00545     // codebooks
00546     put_bits(&pb, 8, venc->ncodebooks - 1);
00547     for (i = 0; i < venc->ncodebooks; i++)
00548         put_codebook_header(&pb, &venc->codebooks[i]);
00549 
00550     // time domain, reserved, zero
00551     put_bits(&pb, 6, 0);
00552     put_bits(&pb, 16, 0);
00553 
00554     // floors
00555     put_bits(&pb, 6, venc->nfloors - 1);
00556     for (i = 0; i < venc->nfloors; i++)
00557         put_floor_header(&pb, &venc->floors[i]);
00558 
00559     // residues
00560     put_bits(&pb, 6, venc->nresidues - 1);
00561     for (i = 0; i < venc->nresidues; i++)
00562         put_residue_header(&pb, &venc->residues[i]);
00563 
00564     // mappings
00565     put_bits(&pb, 6, venc->nmappings - 1);
00566     for (i = 0; i < venc->nmappings; i++) {
00567         vorbis_enc_mapping * mc = &venc->mappings[i];
00568         int j;
00569         put_bits(&pb, 16, 0); // mapping type
00570 
00571         put_bits(&pb, 1, mc->submaps > 1);
00572         if (mc->submaps > 1)
00573             put_bits(&pb, 4, mc->submaps - 1);
00574 
00575         put_bits(&pb, 1, !!mc->coupling_steps);
00576         if (mc->coupling_steps) {
00577             put_bits(&pb, 8, mc->coupling_steps - 1);
00578             for (j = 0; j < mc->coupling_steps; j++) {
00579                 put_bits(&pb, ilog(venc->channels - 1), mc->magnitude[j]);
00580                 put_bits(&pb, ilog(venc->channels - 1), mc->angle[j]);
00581             }
00582         }
00583 
00584         put_bits(&pb, 2, 0); // reserved
00585 
00586         if (mc->submaps > 1)
00587             for (j = 0; j < venc->channels; j++)
00588                 put_bits(&pb, 4, mc->mux[j]);
00589 
00590         for (j = 0; j < mc->submaps; j++) {
00591             put_bits(&pb, 8, 0); // reserved time configuration
00592             put_bits(&pb, 8, mc->floor[j]);
00593             put_bits(&pb, 8, mc->residue[j]);
00594         }
00595     }
00596 
00597     // modes
00598     put_bits(&pb, 6, venc->nmodes - 1);
00599     for (i = 0; i < venc->nmodes; i++) {
00600         put_bits(&pb, 1, venc->modes[i].blockflag);
00601         put_bits(&pb, 16, 0); // reserved window type
00602         put_bits(&pb, 16, 0); // reserved transform type
00603         put_bits(&pb, 8, venc->modes[i].mapping);
00604     }
00605 
00606     put_bits(&pb, 1, 1); // framing
00607 
00608     flush_put_bits(&pb);
00609     hlens[2] = (put_bits_count(&pb) + 7) / 8;
00610 
00611     len = hlens[0] + hlens[1] + hlens[2];
00612     p = *out = av_mallocz(64 + len + len/255);
00613 
00614     *p++ = 2;
00615     p += av_xiphlacing(p, hlens[0]);
00616     p += av_xiphlacing(p, hlens[1]);
00617     buffer_len = 0;
00618     for (i = 0; i < 3; i++) {
00619         memcpy(p, buffer + buffer_len, hlens[i]);
00620         p += hlens[i];
00621         buffer_len += hlens[i];
00622     }
00623 
00624     return p - *out;
00625 }
00626 
00627 static float get_floor_average(vorbis_enc_floor * fc, float * coeffs, int i) {
00628     int begin = fc->list[fc->list[FFMAX(i-1, 0)].sort].x;
00629     int end   = fc->list[fc->list[FFMIN(i+1, fc->values - 1)].sort].x;
00630     int j;
00631     float average = 0;
00632 
00633     for (j = begin; j < end; j++)
00634         average += fabs(coeffs[j]);
00635     return average / (end - begin);
00636 }
00637 
00638 static void floor_fit(vorbis_enc_context * venc, vorbis_enc_floor * fc, float * coeffs, uint_fast16_t * posts, int samples) {
00639     int range = 255 / fc->multiplier + 1;
00640     int i;
00641     float tot_average = 0.;
00642     float averages[fc->values];
00643     for (i = 0; i < fc->values; i++){
00644         averages[i] = get_floor_average(fc, coeffs, i);
00645         tot_average += averages[i];
00646     }
00647     tot_average /= fc->values;
00648     tot_average /= venc->quality;
00649 
00650     for (i = 0; i < fc->values; i++) {
00651         int position = fc->list[fc->list[i].sort].x;
00652         float average = averages[i];
00653         int j;
00654 
00655         average *= pow(tot_average / average, 0.5) * pow(1.25, position/200.); // MAGIC!
00656         for (j = 0; j < range - 1; j++)
00657             if (ff_vorbis_floor1_inverse_db_table[j * fc->multiplier] > average) break;
00658         posts[fc->list[i].sort] = j;
00659     }
00660 }
00661 
00662 static int render_point(int x0, int y0, int x1, int y1, int x) {
00663     return y0 +  (x - x0) * (y1 - y0) / (x1 - x0);
00664 }
00665 
00666 static void floor_encode(vorbis_enc_context * venc, vorbis_enc_floor * fc, PutBitContext * pb, uint_fast16_t * posts, float * floor, int samples) {
00667     int range = 255 / fc->multiplier + 1;
00668     int coded[fc->values]; // first 2 values are unused
00669     int i, counter;
00670 
00671     put_bits(pb, 1, 1); // non zero
00672     put_bits(pb, ilog(range - 1), posts[0]);
00673     put_bits(pb, ilog(range - 1), posts[1]);
00674     coded[0] = coded[1] = 1;
00675 
00676     for (i = 2; i < fc->values; i++) {
00677         int predicted = render_point(fc->list[fc->list[i].low].x,
00678                                      posts[fc->list[i].low],
00679                                      fc->list[fc->list[i].high].x,
00680                                      posts[fc->list[i].high],
00681                                      fc->list[i].x);
00682         int highroom = range - predicted;
00683         int lowroom = predicted;
00684         int room = FFMIN(highroom, lowroom);
00685         if (predicted == posts[i]) {
00686             coded[i] = 0; // must be used later as flag!
00687             continue;
00688         } else {
00689             if (!coded[fc->list[i].low ]) coded[fc->list[i].low ] = -1;
00690             if (!coded[fc->list[i].high]) coded[fc->list[i].high] = -1;
00691         }
00692         if (posts[i] > predicted) {
00693             if (posts[i] - predicted > room)
00694                 coded[i] = posts[i] - predicted + lowroom;
00695             else
00696                 coded[i] = (posts[i] - predicted) << 1;
00697         } else {
00698             if (predicted - posts[i] > room)
00699                 coded[i] = predicted - posts[i] + highroom - 1;
00700             else
00701                 coded[i] = ((predicted - posts[i]) << 1) - 1;
00702         }
00703     }
00704 
00705     counter = 2;
00706     for (i = 0; i < fc->partitions; i++) {
00707         vorbis_enc_floor_class * c = &fc->classes[fc->partition_to_class[i]];
00708         int k, cval = 0, csub = 1<<c->subclass;
00709         if (c->subclass) {
00710             vorbis_enc_codebook * book = &venc->codebooks[c->masterbook];
00711             int cshift = 0;
00712             for (k = 0; k < c->dim; k++) {
00713                 int l;
00714                 for (l = 0; l < csub; l++) {
00715                     int maxval = 1;
00716                     if (c->books[l] != -1)
00717                         maxval = venc->codebooks[c->books[l]].nentries;
00718                     // coded could be -1, but this still works, cause that is 0
00719                     if (coded[counter + k] < maxval) break;
00720                 }
00721                 assert(l != csub);
00722                 cval |= l << cshift;
00723                 cshift += c->subclass;
00724             }
00725             put_codeword(pb, book, cval);
00726         }
00727         for (k = 0; k < c->dim; k++) {
00728             int book = c->books[cval & (csub-1)];
00729             int entry = coded[counter++];
00730             cval >>= c->subclass;
00731             if (book == -1) continue;
00732             if (entry == -1) entry = 0;
00733             put_codeword(pb, &venc->codebooks[book], entry);
00734         }
00735     }
00736 
00737     ff_vorbis_floor1_render_list(fc->list, fc->values, posts, coded, fc->multiplier, floor, samples);
00738 }
00739 
00740 static float * put_vector(vorbis_enc_codebook * book, PutBitContext * pb, float * num) {
00741     int i, entry = -1;
00742     float distance = FLT_MAX;
00743     assert(book->dimentions);
00744     for (i = 0; i < book->nentries; i++) {
00745         float * vec = book->dimentions + i * book->ndimentions, d = book->pow2[i];
00746         int j;
00747         if (!book->lens[i]) continue;
00748         for (j = 0; j < book->ndimentions; j++)
00749             d -= vec[j] * num[j];
00750         if (distance > d) {
00751             entry = i;
00752             distance = d;
00753         }
00754     }
00755     put_codeword(pb, book, entry);
00756     return &book->dimentions[entry * book->ndimentions];
00757 }
00758 
00759 static void residue_encode(vorbis_enc_context * venc, vorbis_enc_residue * rc, PutBitContext * pb, float * coeffs, int samples, int real_ch) {
00760     int pass, i, j, p, k;
00761     int psize = rc->partition_size;
00762     int partitions = (rc->end - rc->begin) / psize;
00763     int channels = (rc->type == 2) ? 1 : real_ch;
00764     int classes[channels][partitions];
00765     int classwords = venc->codebooks[rc->classbook].ndimentions;
00766 
00767     assert(rc->type == 2);
00768     assert(real_ch == 2);
00769     for (p = 0; p < partitions; p++) {
00770         float max1 = 0., max2 = 0.;
00771         int s = rc->begin + p * psize;
00772         for (k = s; k < s + psize; k += 2) {
00773             max1 = FFMAX(max1, fabs(coeffs[          k / real_ch]));
00774             max2 = FFMAX(max2, fabs(coeffs[samples + k / real_ch]));
00775         }
00776 
00777         for (i = 0; i < rc->classifications - 1; i++) {
00778             if (max1 < rc->maxes[i][0] && max2 < rc->maxes[i][1]) break;
00779         }
00780         classes[0][p] = i;
00781     }
00782 
00783     for (pass = 0; pass < 8; pass++) {
00784         p = 0;
00785         while (p < partitions) {
00786             if (pass == 0)
00787                 for (j = 0; j < channels; j++) {
00788                     vorbis_enc_codebook * book = &venc->codebooks[rc->classbook];
00789                     int entry = 0;
00790                     for (i = 0; i < classwords; i++) {
00791                         entry *= rc->classifications;
00792                         entry += classes[j][p + i];
00793                     }
00794                     put_codeword(pb, book, entry);
00795                 }
00796             for (i = 0; i < classwords && p < partitions; i++, p++) {
00797                 for (j = 0; j < channels; j++) {
00798                     int nbook = rc->books[classes[j][p]][pass];
00799                     vorbis_enc_codebook * book = &venc->codebooks[nbook];
00800                     float * buf = coeffs + samples*j + rc->begin + p*psize;
00801                     if (nbook == -1) continue;
00802 
00803                     assert(rc->type == 0 || rc->type == 2);
00804                     assert(!(psize % book->ndimentions));
00805 
00806                     if (rc->type == 0) {
00807                         for (k = 0; k < psize; k += book->ndimentions) {
00808                             float * a = put_vector(book, pb, &buf[k]);
00809                             int l;
00810                             for (l = 0; l < book->ndimentions; l++)
00811                                 buf[k + l] -= a[l];
00812                         }
00813                     } else {
00814                         int s = rc->begin + p * psize, a1, b1;
00815                         a1 = (s % real_ch) * samples;
00816                         b1 =  s / real_ch;
00817                         s = real_ch * samples;
00818                         for (k = 0; k < psize; k += book->ndimentions) {
00819                             int dim, a2 = a1, b2 = b1;
00820                             float vec[book->ndimentions], * pv = vec;
00821                             for (dim = book->ndimentions; dim--; ) {
00822                                 *pv++ = coeffs[a2 + b2];
00823                                 if ((a2 += samples) == s) {
00824                                     a2=0;
00825                                     b2++;
00826                                 }
00827                             }
00828                             pv = put_vector(book, pb, vec);
00829                             for (dim = book->ndimentions; dim--; ) {
00830                                 coeffs[a1 + b1] -= *pv++;
00831                                 if ((a1 += samples) == s) {
00832                                     a1=0;
00833                                     b1++;
00834                                 }
00835                             }
00836                         }
00837                     }
00838                 }
00839             }
00840         }
00841     }
00842 }
00843 
00844 static int apply_window_and_mdct(vorbis_enc_context * venc, signed short * audio, int samples) {
00845     int i, j, channel;
00846     const float * win = venc->win[0];
00847     int window_len = 1 << (venc->log2_blocksize[0] - 1);
00848     float n = (float)(1 << venc->log2_blocksize[0]) / 4.;
00849     // FIXME use dsp
00850 
00851     if (!venc->have_saved && !samples) return 0;
00852 
00853     if (venc->have_saved) {
00854         for (channel = 0; channel < venc->channels; channel++) {
00855             memcpy(venc->samples + channel*window_len*2, venc->saved + channel*window_len, sizeof(float)*window_len);
00856         }
00857     } else {
00858         for (channel = 0; channel < venc->channels; channel++) {
00859             memset(venc->samples + channel*window_len*2, 0, sizeof(float)*window_len);
00860         }
00861     }
00862 
00863     if (samples) {
00864         for (channel = 0; channel < venc->channels; channel++) {
00865             float * offset = venc->samples + channel*window_len*2 + window_len;
00866             j = channel;
00867             for (i = 0; i < samples; i++, j += venc->channels)
00868                 offset[i] = -audio[j] / 32768. / n * win[window_len - i - 1]; //FIXME find out why the sign has to be fliped
00869         }
00870     } else {
00871         for (channel = 0; channel < venc->channels; channel++) {
00872             memset(venc->samples + channel*window_len*2 + window_len, 0, sizeof(float)*window_len);
00873         }
00874     }
00875 
00876     for (channel = 0; channel < venc->channels; channel++) {
00877         ff_mdct_calc(&venc->mdct[0], venc->coeffs + channel*window_len, venc->samples + channel*window_len*2);
00878     }
00879 
00880     if (samples) {
00881         for (channel = 0; channel < venc->channels; channel++) {
00882             float * offset = venc->saved + channel*window_len;
00883             j = channel;
00884             for (i = 0; i < samples; i++, j += venc->channels)
00885                 offset[i] = -audio[j] / 32768. / n * win[i]; //FIXME find out why the sign has to be fliped
00886         }
00887         venc->have_saved = 1;
00888     } else {
00889         venc->have_saved = 0;
00890     }
00891     return 1;
00892 }
00893 
00894 static av_cold int vorbis_encode_init(AVCodecContext * avccontext)
00895 {
00896     vorbis_enc_context * venc = avccontext->priv_data;
00897 
00898     if (avccontext->channels != 2) {
00899         av_log(avccontext, AV_LOG_ERROR, "Current FFmpeg Vorbis encoder only supports 2 channels.\n");
00900         return -1;
00901     }
00902 
00903     create_vorbis_context(venc, avccontext);
00904 
00905     if (avccontext->flags & CODEC_FLAG_QSCALE)
00906         venc->quality = avccontext->global_quality / (float)FF_QP2LAMBDA / 10.;
00907     else
00908         venc->quality = 1.;
00909     venc->quality *= venc->quality;
00910 
00911     avccontext->extradata_size = put_main_header(venc, (uint8_t**)&avccontext->extradata);
00912 
00913     avccontext->frame_size = 1 << (venc->log2_blocksize[0] - 1);
00914 
00915     avccontext->coded_frame = avcodec_alloc_frame();
00916     avccontext->coded_frame->key_frame = 1;
00917 
00918     return 0;
00919 }
00920 
00921 static int vorbis_encode_frame(AVCodecContext * avccontext, unsigned char * packets, int buf_size, void *data)
00922 {
00923     vorbis_enc_context * venc = avccontext->priv_data;
00924     signed short * audio = data;
00925     int samples = data ? avccontext->frame_size : 0;
00926     vorbis_enc_mode * mode;
00927     vorbis_enc_mapping * mapping;
00928     PutBitContext pb;
00929     int i;
00930 
00931     if (!apply_window_and_mdct(venc, audio, samples)) return 0;
00932     samples = 1 << (venc->log2_blocksize[0] - 1);
00933 
00934     init_put_bits(&pb, packets, buf_size);
00935 
00936     put_bits(&pb, 1, 0); // magic bit
00937 
00938     put_bits(&pb, ilog(venc->nmodes - 1), 0); // 0 bits, the mode
00939 
00940     mode = &venc->modes[0];
00941     mapping = &venc->mappings[mode->mapping];
00942     if (mode->blockflag) {
00943         put_bits(&pb, 1, 0);
00944         put_bits(&pb, 1, 0);
00945     }
00946 
00947     for (i = 0; i < venc->channels; i++) {
00948         vorbis_enc_floor * fc = &venc->floors[mapping->floor[mapping->mux[i]]];
00949         uint_fast16_t posts[fc->values];
00950         floor_fit(venc, fc, &venc->coeffs[i * samples], posts, samples);
00951         floor_encode(venc, fc, &pb, posts, &venc->floor[i * samples], samples);
00952     }
00953 
00954     for (i = 0; i < venc->channels * samples; i++) {
00955         venc->coeffs[i] /= venc->floor[i];
00956     }
00957 
00958     for (i = 0; i < mapping->coupling_steps; i++) {
00959         float * mag = venc->coeffs + mapping->magnitude[i] * samples;
00960         float * ang = venc->coeffs + mapping->angle[i] * samples;
00961         int j;
00962         for (j = 0; j < samples; j++) {
00963             float a = ang[j];
00964             ang[j] -= mag[j];
00965             if (mag[j] > 0) ang[j] = -ang[j];
00966             if (ang[j] < 0) mag[j] = a;
00967         }
00968     }
00969 
00970     residue_encode(venc, &venc->residues[mapping->residue[mapping->mux[0]]], &pb, venc->coeffs, samples, venc->channels);
00971 
00972     avccontext->coded_frame->pts = venc->sample_count;
00973     venc->sample_count += avccontext->frame_size;
00974     flush_put_bits(&pb);
00975     return (put_bits_count(&pb) + 7) / 8;
00976 }
00977 
00978 
00979 static av_cold int vorbis_encode_close(AVCodecContext * avccontext)
00980 {
00981     vorbis_enc_context * venc = avccontext->priv_data;
00982     int i;
00983 
00984     if (venc->codebooks)
00985         for (i = 0; i < venc->ncodebooks; i++) {
00986             av_freep(&venc->codebooks[i].lens);
00987             av_freep(&venc->codebooks[i].codewords);
00988             av_freep(&venc->codebooks[i].quantlist);
00989             av_freep(&venc->codebooks[i].dimentions);
00990             av_freep(&venc->codebooks[i].pow2);
00991         }
00992     av_freep(&venc->codebooks);
00993 
00994     if (venc->floors)
00995         for (i = 0; i < venc->nfloors; i++) {
00996             int j;
00997             if (venc->floors[i].classes)
00998                 for (j = 0; j < venc->floors[i].nclasses; j++)
00999                     av_freep(&venc->floors[i].classes[j].books);
01000             av_freep(&venc->floors[i].classes);
01001             av_freep(&venc->floors[i].partition_to_class);
01002             av_freep(&venc->floors[i].list);
01003         }
01004     av_freep(&venc->floors);
01005 
01006     if (venc->residues)
01007         for (i = 0; i < venc->nresidues; i++) {
01008             av_freep(&venc->residues[i].books);
01009             av_freep(&venc->residues[i].maxes);
01010         }
01011     av_freep(&venc->residues);
01012 
01013     if (venc->mappings)
01014         for (i = 0; i < venc->nmappings; i++) {
01015             av_freep(&venc->mappings[i].mux);
01016             av_freep(&venc->mappings[i].floor);
01017             av_freep(&venc->mappings[i].residue);
01018             av_freep(&venc->mappings[i].magnitude);
01019             av_freep(&venc->mappings[i].angle);
01020         }
01021     av_freep(&venc->mappings);
01022 
01023     av_freep(&venc->modes);
01024 
01025     av_freep(&venc->saved);
01026     av_freep(&venc->samples);
01027     av_freep(&venc->floor);
01028     av_freep(&venc->coeffs);
01029 
01030     ff_mdct_end(&venc->mdct[0]);
01031     ff_mdct_end(&venc->mdct[1]);
01032 
01033     av_freep(&avccontext->coded_frame);
01034     av_freep(&avccontext->extradata);
01035 
01036     return 0 ;
01037 }
01038 
01039 AVCodec vorbis_encoder = {
01040     "vorbis",
01041     CODEC_TYPE_AUDIO,
01042     CODEC_ID_VORBIS,
01043     sizeof(vorbis_enc_context),
01044     vorbis_encode_init,
01045     vorbis_encode_frame,
01046     vorbis_encode_close,
01047     .capabilities= CODEC_CAP_DELAY,
01048     .sample_fmts = (enum SampleFormat[]){SAMPLE_FMT_S16,SAMPLE_FMT_NONE},
01049     .long_name = NULL_IF_CONFIG_SMALL("Vorbis"),
01050 };

Generated on Sat Feb 16 2013 09:23:14 for ffmpeg by  doxygen 1.7.1