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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 "fft.h"
00031 #include "vorbis.h"
00032 #include "vorbis_enc_data.h"
00033 
00034 #define BITSTREAM_WRITER_LE
00035 #include "put_bits.h"
00036 
00037 #undef NDEBUG
00038 #include <assert.h>
00039 
00040 typedef struct {
00041     int nentries;
00042     uint8_t *lens;
00043     uint32_t *codewords;
00044     int ndimentions;
00045     float min;
00046     float delta;
00047     int seq_p;
00048     int lookup;
00049     int *quantlist;
00050     float *dimentions;
00051     float *pow2;
00052 } vorbis_enc_codebook;
00053 
00054 typedef struct {
00055     int dim;
00056     int subclass;
00057     int masterbook;
00058     int *books;
00059 } vorbis_enc_floor_class;
00060 
00061 typedef struct {
00062     int partitions;
00063     int *partition_to_class;
00064     int nclasses;
00065     vorbis_enc_floor_class *classes;
00066     int multiplier;
00067     int rangebits;
00068     int values;
00069     vorbis_floor1_entry *list;
00070 } vorbis_enc_floor;
00071 
00072 typedef struct {
00073     int type;
00074     int begin;
00075     int end;
00076     int partition_size;
00077     int classifications;
00078     int classbook;
00079     int8_t (*books)[8];
00080     float (*maxes)[2];
00081 } vorbis_enc_residue;
00082 
00083 typedef struct {
00084     int submaps;
00085     int *mux;
00086     int *floor;
00087     int *residue;
00088     int coupling_steps;
00089     int *magnitude;
00090     int *angle;
00091 } vorbis_enc_mapping;
00092 
00093 typedef struct {
00094     int blockflag;
00095     int mapping;
00096 } vorbis_enc_mode;
00097 
00098 typedef struct {
00099     int channels;
00100     int sample_rate;
00101     int log2_blocksize[2];
00102     FFTContext mdct[2];
00103     const float *win[2];
00104     int have_saved;
00105     float *saved;
00106     float *samples;
00107     float *floor;  // also used for tmp values for mdct
00108     float *coeffs; // also used for residue after floor
00109     float quality;
00110 
00111     int ncodebooks;
00112     vorbis_enc_codebook *codebooks;
00113 
00114     int nfloors;
00115     vorbis_enc_floor *floors;
00116 
00117     int nresidues;
00118     vorbis_enc_residue *residues;
00119 
00120     int nmappings;
00121     vorbis_enc_mapping *mappings;
00122 
00123     int nmodes;
00124     vorbis_enc_mode *modes;
00125 
00126     int64_t sample_count;
00127 } vorbis_enc_context;
00128 
00129 static inline void put_codeword(PutBitContext *pb, vorbis_enc_codebook *cb,
00130                                 int entry)
00131 {
00132     assert(entry >= 0);
00133     assert(entry < cb->nentries);
00134     assert(cb->lens[entry]);
00135     put_bits(pb, cb->lens[entry], cb->codewords[entry]);
00136 }
00137 
00138 static int cb_lookup_vals(int lookup, int dimentions, int entries)
00139 {
00140     if (lookup == 1)
00141         return ff_vorbis_nth_root(entries, dimentions);
00142     else if (lookup == 2)
00143         return dimentions *entries;
00144     return 0;
00145 }
00146 
00147 static void ready_codebook(vorbis_enc_codebook *cb)
00148 {
00149     int i;
00150 
00151     ff_vorbis_len2vlc(cb->lens, cb->codewords, cb->nentries);
00152 
00153     if (!cb->lookup) {
00154         cb->pow2 = cb->dimentions = NULL;
00155     } else {
00156         int vals = cb_lookup_vals(cb->lookup, cb->ndimentions, cb->nentries);
00157         cb->dimentions = av_malloc(sizeof(float) * cb->nentries * cb->ndimentions);
00158         cb->pow2 = av_mallocz(sizeof(float) * cb->nentries);
00159         for (i = 0; i < cb->nentries; i++) {
00160             float last = 0;
00161             int j;
00162             int div = 1;
00163             for (j = 0; j < cb->ndimentions; j++) {
00164                 int off;
00165                 if (cb->lookup == 1)
00166                     off = (i / div) % vals; // lookup type 1
00167                 else
00168                     off = i * cb->ndimentions + j; // lookup type 2
00169 
00170                 cb->dimentions[i * cb->ndimentions + j] = last + cb->min + cb->quantlist[off] * cb->delta;
00171                 if (cb->seq_p)
00172                     last = cb->dimentions[i * cb->ndimentions + j];
00173                 cb->pow2[i] += cb->dimentions[i * cb->ndimentions + j] * cb->dimentions[i * cb->ndimentions + j];
00174                 div *= vals;
00175             }
00176             cb->pow2[i] /= 2.;
00177         }
00178     }
00179 }
00180 
00181 static void ready_residue(vorbis_enc_residue *rc, vorbis_enc_context *venc)
00182 {
00183     int i;
00184     assert(rc->type == 2);
00185     rc->maxes = av_mallocz(sizeof(float[2]) * rc->classifications);
00186     for (i = 0; i < rc->classifications; i++) {
00187         int j;
00188         vorbis_enc_codebook * cb;
00189         for (j = 0; j < 8; j++)
00190             if (rc->books[i][j] != -1)
00191                 break;
00192         if (j == 8) // zero
00193             continue;
00194         cb = &venc->codebooks[rc->books[i][j]];
00195         assert(cb->ndimentions >= 2);
00196         assert(cb->lookup);
00197 
00198         for (j = 0; j < cb->nentries; j++) {
00199             float a;
00200             if (!cb->lens[j])
00201                 continue;
00202             a = fabs(cb->dimentions[j * cb->ndimentions]);
00203             if (a > rc->maxes[i][0])
00204                 rc->maxes[i][0] = a;
00205             a = fabs(cb->dimentions[j * cb->ndimentions + 1]);
00206             if (a > rc->maxes[i][1])
00207                 rc->maxes[i][1] = a;
00208         }
00209     }
00210     // small bias
00211     for (i = 0; i < rc->classifications; i++) {
00212         rc->maxes[i][0] += 0.8;
00213         rc->maxes[i][1] += 0.8;
00214     }
00215 }
00216 
00217 static void create_vorbis_context(vorbis_enc_context *venc,
00218                                   AVCodecContext *avccontext)
00219 {
00220     vorbis_enc_floor   *fc;
00221     vorbis_enc_residue *rc;
00222     vorbis_enc_mapping *mc;
00223     int i, book;
00224 
00225     venc->channels    = avccontext->channels;
00226     venc->sample_rate = avccontext->sample_rate;
00227     venc->log2_blocksize[0] = venc->log2_blocksize[1] = 11;
00228 
00229     venc->ncodebooks = FF_ARRAY_ELEMS(cvectors);
00230     venc->codebooks  = av_malloc(sizeof(vorbis_enc_codebook) * venc->ncodebooks);
00231 
00232     // codebook 0..14 - floor1 book, values 0..255
00233     // codebook 15 residue masterbook
00234     // codebook 16..29 residue
00235     for (book = 0; book < venc->ncodebooks; book++) {
00236         vorbis_enc_codebook *cb = &venc->codebooks[book];
00237         int vals;
00238         cb->ndimentions = cvectors[book].dim;
00239         cb->nentries    = cvectors[book].real_len;
00240         cb->min         = cvectors[book].min;
00241         cb->delta       = cvectors[book].delta;
00242         cb->lookup      = cvectors[book].lookup;
00243         cb->seq_p       = 0;
00244 
00245         cb->lens      = av_malloc(sizeof(uint8_t)  * cb->nentries);
00246         cb->codewords = av_malloc(sizeof(uint32_t) * cb->nentries);
00247         memcpy(cb->lens, cvectors[book].clens, cvectors[book].len);
00248         memset(cb->lens + cvectors[book].len, 0, cb->nentries - cvectors[book].len);
00249 
00250         if (cb->lookup) {
00251             vals = cb_lookup_vals(cb->lookup, cb->ndimentions, cb->nentries);
00252             cb->quantlist = av_malloc(sizeof(int) * vals);
00253             for (i = 0; i < vals; i++)
00254                 cb->quantlist[i] = cvectors[book].quant[i];
00255         } else {
00256             cb->quantlist = NULL;
00257         }
00258         ready_codebook(cb);
00259     }
00260 
00261     venc->nfloors = 1;
00262     venc->floors  = av_malloc(sizeof(vorbis_enc_floor) * venc->nfloors);
00263 
00264     // just 1 floor
00265     fc = &venc->floors[0];
00266     fc->partitions         = 8;
00267     fc->partition_to_class = av_malloc(sizeof(int) * fc->partitions);
00268     fc->nclasses           = 0;
00269     for (i = 0; i < fc->partitions; i++) {
00270         static const int a[] = {0, 1, 2, 2, 3, 3, 4, 4};
00271         fc->partition_to_class[i] = a[i];
00272         fc->nclasses = FFMAX(fc->nclasses, fc->partition_to_class[i]);
00273     }
00274     fc->nclasses++;
00275     fc->classes = av_malloc(sizeof(vorbis_enc_floor_class) * fc->nclasses);
00276     for (i = 0; i < fc->nclasses; i++) {
00277         vorbis_enc_floor_class * c = &fc->classes[i];
00278         int j, books;
00279         c->dim        = floor_classes[i].dim;
00280         c->subclass   = floor_classes[i].subclass;
00281         c->masterbook = floor_classes[i].masterbook;
00282         books         = (1 << c->subclass);
00283         c->books      = av_malloc(sizeof(int) * books);
00284         for (j = 0; j < books; j++)
00285             c->books[j] = floor_classes[i].nbooks[j];
00286     }
00287     fc->multiplier = 2;
00288     fc->rangebits  = venc->log2_blocksize[0] - 1;
00289 
00290     fc->values = 2;
00291     for (i = 0; i < fc->partitions; i++)
00292         fc->values += fc->classes[fc->partition_to_class[i]].dim;
00293 
00294     fc->list = av_malloc(sizeof(vorbis_floor1_entry) * fc->values);
00295     fc->list[0].x = 0;
00296     fc->list[1].x = 1 << fc->rangebits;
00297     for (i = 2; i < fc->values; i++) {
00298         static const int a[] = {
00299              93, 23,372,  6, 46,186,750, 14, 33, 65,
00300             130,260,556,  3, 10, 18, 28, 39, 55, 79,
00301             111,158,220,312,464,650,850
00302         };
00303         fc->list[i].x = a[i - 2];
00304     }
00305     ff_vorbis_ready_floor1_list(fc->list, fc->values);
00306 
00307     venc->nresidues = 1;
00308     venc->residues  = av_malloc(sizeof(vorbis_enc_residue) * venc->nresidues);
00309 
00310     // single residue
00311     rc = &venc->residues[0];
00312     rc->type            = 2;
00313     rc->begin           = 0;
00314     rc->end             = 1600;
00315     rc->partition_size  = 32;
00316     rc->classifications = 10;
00317     rc->classbook       = 15;
00318     rc->books           = av_malloc(sizeof(*rc->books) * rc->classifications);
00319     {
00320         static const int8_t a[10][8] = {
00321             { -1, -1, -1, -1, -1, -1, -1, -1, },
00322             { -1, -1, 16, -1, -1, -1, -1, -1, },
00323             { -1, -1, 17, -1, -1, -1, -1, -1, },
00324             { -1, -1, 18, -1, -1, -1, -1, -1, },
00325             { -1, -1, 19, -1, -1, -1, -1, -1, },
00326             { -1, -1, 20, -1, -1, -1, -1, -1, },
00327             { -1, -1, 21, -1, -1, -1, -1, -1, },
00328             { 22, 23, -1, -1, -1, -1, -1, -1, },
00329             { 24, 25, -1, -1, -1, -1, -1, -1, },
00330             { 26, 27, 28, -1, -1, -1, -1, -1, },
00331         };
00332         memcpy(rc->books, a, sizeof a);
00333     }
00334     ready_residue(rc, venc);
00335 
00336     venc->nmappings = 1;
00337     venc->mappings  = av_malloc(sizeof(vorbis_enc_mapping) * venc->nmappings);
00338 
00339     // single mapping
00340     mc = &venc->mappings[0];
00341     mc->submaps = 1;
00342     mc->mux     = av_malloc(sizeof(int) * venc->channels);
00343     for (i = 0; i < venc->channels; i++)
00344         mc->mux[i] = 0;
00345     mc->floor   = av_malloc(sizeof(int) * mc->submaps);
00346     mc->residue = av_malloc(sizeof(int) * mc->submaps);
00347     for (i = 0; i < mc->submaps; i++) {
00348         mc->floor[i]   = 0;
00349         mc->residue[i] = 0;
00350     }
00351     mc->coupling_steps = venc->channels == 2 ? 1 : 0;
00352     mc->magnitude      = av_malloc(sizeof(int) * mc->coupling_steps);
00353     mc->angle          = av_malloc(sizeof(int) * mc->coupling_steps);
00354     if (mc->coupling_steps) {
00355         mc->magnitude[0] = 0;
00356         mc->angle[0]     = 1;
00357     }
00358 
00359     venc->nmodes = 1;
00360     venc->modes  = av_malloc(sizeof(vorbis_enc_mode) * venc->nmodes);
00361 
00362     // single mode
00363     venc->modes[0].blockflag = 0;
00364     venc->modes[0].mapping   = 0;
00365 
00366     venc->have_saved = 0;
00367     venc->saved      = av_malloc(sizeof(float) * venc->channels * (1 << venc->log2_blocksize[1]) / 2);
00368     venc->samples    = av_malloc(sizeof(float) * venc->channels * (1 << venc->log2_blocksize[1]));
00369     venc->floor      = av_malloc(sizeof(float) * venc->channels * (1 << venc->log2_blocksize[1]) / 2);
00370     venc->coeffs     = av_malloc(sizeof(float) * venc->channels * (1 << venc->log2_blocksize[1]) / 2);
00371 
00372     venc->win[0] = ff_vorbis_vwin[venc->log2_blocksize[0] - 6];
00373     venc->win[1] = ff_vorbis_vwin[venc->log2_blocksize[1] - 6];
00374 
00375     ff_mdct_init(&venc->mdct[0], venc->log2_blocksize[0], 0, 1.0);
00376     ff_mdct_init(&venc->mdct[1], venc->log2_blocksize[1], 0, 1.0);
00377 }
00378 
00379 static void put_float(PutBitContext *pb, float f)
00380 {
00381     int exp, mant;
00382     uint32_t res = 0;
00383     mant = (int)ldexp(frexp(f, &exp), 20);
00384     exp += 788 - 20;
00385     if (mant < 0) {
00386         res |= (1 << 31);
00387         mant = -mant;
00388     }
00389     res |= mant | (exp << 21);
00390     put_bits32(pb, res);
00391 }
00392 
00393 static void put_codebook_header(PutBitContext *pb, vorbis_enc_codebook *cb)
00394 {
00395     int i;
00396     int ordered = 0;
00397 
00398     put_bits(pb, 24, 0x564342); //magic
00399     put_bits(pb, 16, cb->ndimentions);
00400     put_bits(pb, 24, cb->nentries);
00401 
00402     for (i = 1; i < cb->nentries; i++)
00403         if (cb->lens[i] < cb->lens[i-1])
00404             break;
00405     if (i == cb->nentries)
00406         ordered = 1;
00407 
00408     put_bits(pb, 1, ordered);
00409     if (ordered) {
00410         int len = cb->lens[0];
00411         put_bits(pb, 5, len - 1);
00412         i = 0;
00413         while (i < cb->nentries) {
00414             int j;
00415             for (j = 0; j+i < cb->nentries; j++)
00416                 if (cb->lens[j+i] != len)
00417                     break;
00418             put_bits(pb, ilog(cb->nentries - i), j);
00419             i += j;
00420             len++;
00421         }
00422     } else {
00423         int sparse = 0;
00424         for (i = 0; i < cb->nentries; i++)
00425             if (!cb->lens[i])
00426                 break;
00427         if (i != cb->nentries)
00428             sparse = 1;
00429         put_bits(pb, 1, sparse);
00430 
00431         for (i = 0; i < cb->nentries; i++) {
00432             if (sparse)
00433                 put_bits(pb, 1, !!cb->lens[i]);
00434             if (cb->lens[i])
00435                 put_bits(pb, 5, cb->lens[i] - 1);
00436         }
00437     }
00438 
00439     put_bits(pb, 4, cb->lookup);
00440     if (cb->lookup) {
00441         int tmp  = cb_lookup_vals(cb->lookup, cb->ndimentions, cb->nentries);
00442         int bits = ilog(cb->quantlist[0]);
00443 
00444         for (i = 1; i < tmp; i++)
00445             bits = FFMAX(bits, ilog(cb->quantlist[i]));
00446 
00447         put_float(pb, cb->min);
00448         put_float(pb, cb->delta);
00449 
00450         put_bits(pb, 4, bits - 1);
00451         put_bits(pb, 1, cb->seq_p);
00452 
00453         for (i = 0; i < tmp; i++)
00454             put_bits(pb, bits, cb->quantlist[i]);
00455     }
00456 }
00457 
00458 static void put_floor_header(PutBitContext *pb, vorbis_enc_floor *fc)
00459 {
00460     int i;
00461 
00462     put_bits(pb, 16, 1); // type, only floor1 is supported
00463 
00464     put_bits(pb, 5, fc->partitions);
00465 
00466     for (i = 0; i < fc->partitions; i++)
00467         put_bits(pb, 4, fc->partition_to_class[i]);
00468 
00469     for (i = 0; i < fc->nclasses; i++) {
00470         int j, books;
00471 
00472         put_bits(pb, 3, fc->classes[i].dim - 1);
00473         put_bits(pb, 2, fc->classes[i].subclass);
00474 
00475         if (fc->classes[i].subclass)
00476             put_bits(pb, 8, fc->classes[i].masterbook);
00477 
00478         books = (1 << fc->classes[i].subclass);
00479 
00480         for (j = 0; j < books; j++)
00481             put_bits(pb, 8, fc->classes[i].books[j] + 1);
00482     }
00483 
00484     put_bits(pb, 2, fc->multiplier - 1);
00485     put_bits(pb, 4, fc->rangebits);
00486 
00487     for (i = 2; i < fc->values; i++)
00488         put_bits(pb, fc->rangebits, fc->list[i].x);
00489 }
00490 
00491 static void put_residue_header(PutBitContext *pb, vorbis_enc_residue *rc)
00492 {
00493     int i;
00494 
00495     put_bits(pb, 16, rc->type);
00496 
00497     put_bits(pb, 24, rc->begin);
00498     put_bits(pb, 24, rc->end);
00499     put_bits(pb, 24, rc->partition_size - 1);
00500     put_bits(pb, 6, rc->classifications - 1);
00501     put_bits(pb, 8, rc->classbook);
00502 
00503     for (i = 0; i < rc->classifications; i++) {
00504         int j, tmp = 0;
00505         for (j = 0; j < 8; j++)
00506             tmp |= (rc->books[i][j] != -1) << j;
00507 
00508         put_bits(pb, 3, tmp & 7);
00509         put_bits(pb, 1, tmp > 7);
00510 
00511         if (tmp > 7)
00512             put_bits(pb, 5, tmp >> 3);
00513     }
00514 
00515     for (i = 0; i < rc->classifications; i++) {
00516         int j;
00517         for (j = 0; j < 8; j++)
00518             if (rc->books[i][j] != -1)
00519                 put_bits(pb, 8, rc->books[i][j]);
00520     }
00521 }
00522 
00523 static int put_main_header(vorbis_enc_context *venc, uint8_t **out)
00524 {
00525     int i;
00526     PutBitContext pb;
00527     uint8_t buffer[50000] = {0}, *p = buffer;
00528     int buffer_len = sizeof buffer;
00529     int len, hlens[3];
00530 
00531     // identification header
00532     init_put_bits(&pb, p, buffer_len);
00533     put_bits(&pb, 8, 1); //magic
00534     for (i = 0; "vorbis"[i]; i++)
00535         put_bits(&pb, 8, "vorbis"[i]);
00536     put_bits32(&pb, 0); // version
00537     put_bits(&pb,  8, venc->channels);
00538     put_bits32(&pb, venc->sample_rate);
00539     put_bits32(&pb, 0); // bitrate
00540     put_bits32(&pb, 0); // bitrate
00541     put_bits32(&pb, 0); // bitrate
00542     put_bits(&pb,  4, venc->log2_blocksize[0]);
00543     put_bits(&pb,  4, venc->log2_blocksize[1]);
00544     put_bits(&pb,  1, 1); // framing
00545 
00546     flush_put_bits(&pb);
00547     hlens[0] = put_bits_count(&pb) >> 3;
00548     buffer_len -= hlens[0];
00549     p += hlens[0];
00550 
00551     // comment header
00552     init_put_bits(&pb, p, buffer_len);
00553     put_bits(&pb, 8, 3); //magic
00554     for (i = 0; "vorbis"[i]; i++)
00555         put_bits(&pb, 8, "vorbis"[i]);
00556     put_bits32(&pb, 0); // vendor length TODO
00557     put_bits32(&pb, 0); // amount of comments
00558     put_bits(&pb,  1, 1); // framing
00559 
00560     flush_put_bits(&pb);
00561     hlens[1] = put_bits_count(&pb) >> 3;
00562     buffer_len -= hlens[1];
00563     p += hlens[1];
00564 
00565     // setup header
00566     init_put_bits(&pb, p, buffer_len);
00567     put_bits(&pb, 8, 5); //magic
00568     for (i = 0; "vorbis"[i]; i++)
00569         put_bits(&pb, 8, "vorbis"[i]);
00570 
00571     // codebooks
00572     put_bits(&pb, 8, venc->ncodebooks - 1);
00573     for (i = 0; i < venc->ncodebooks; i++)
00574         put_codebook_header(&pb, &venc->codebooks[i]);
00575 
00576     // time domain, reserved, zero
00577     put_bits(&pb,  6, 0);
00578     put_bits(&pb, 16, 0);
00579 
00580     // floors
00581     put_bits(&pb, 6, venc->nfloors - 1);
00582     for (i = 0; i < venc->nfloors; i++)
00583         put_floor_header(&pb, &venc->floors[i]);
00584 
00585     // residues
00586     put_bits(&pb, 6, venc->nresidues - 1);
00587     for (i = 0; i < venc->nresidues; i++)
00588         put_residue_header(&pb, &venc->residues[i]);
00589 
00590     // mappings
00591     put_bits(&pb, 6, venc->nmappings - 1);
00592     for (i = 0; i < venc->nmappings; i++) {
00593         vorbis_enc_mapping *mc = &venc->mappings[i];
00594         int j;
00595         put_bits(&pb, 16, 0); // mapping type
00596 
00597         put_bits(&pb, 1, mc->submaps > 1);
00598         if (mc->submaps > 1)
00599             put_bits(&pb, 4, mc->submaps - 1);
00600 
00601         put_bits(&pb, 1, !!mc->coupling_steps);
00602         if (mc->coupling_steps) {
00603             put_bits(&pb, 8, mc->coupling_steps - 1);
00604             for (j = 0; j < mc->coupling_steps; j++) {
00605                 put_bits(&pb, ilog(venc->channels - 1), mc->magnitude[j]);
00606                 put_bits(&pb, ilog(venc->channels - 1), mc->angle[j]);
00607             }
00608         }
00609 
00610         put_bits(&pb, 2, 0); // reserved
00611 
00612         if (mc->submaps > 1)
00613             for (j = 0; j < venc->channels; j++)
00614                 put_bits(&pb, 4, mc->mux[j]);
00615 
00616         for (j = 0; j < mc->submaps; j++) {
00617             put_bits(&pb, 8, 0); // reserved time configuration
00618             put_bits(&pb, 8, mc->floor[j]);
00619             put_bits(&pb, 8, mc->residue[j]);
00620         }
00621     }
00622 
00623     // modes
00624     put_bits(&pb, 6, venc->nmodes - 1);
00625     for (i = 0; i < venc->nmodes; i++) {
00626         put_bits(&pb, 1, venc->modes[i].blockflag);
00627         put_bits(&pb, 16, 0); // reserved window type
00628         put_bits(&pb, 16, 0); // reserved transform type
00629         put_bits(&pb, 8, venc->modes[i].mapping);
00630     }
00631 
00632     put_bits(&pb, 1, 1); // framing
00633 
00634     flush_put_bits(&pb);
00635     hlens[2] = put_bits_count(&pb) >> 3;
00636 
00637     len = hlens[0] + hlens[1] + hlens[2];
00638     p = *out = av_mallocz(64 + len + len/255);
00639 
00640     *p++ = 2;
00641     p += av_xiphlacing(p, hlens[0]);
00642     p += av_xiphlacing(p, hlens[1]);
00643     buffer_len = 0;
00644     for (i = 0; i < 3; i++) {
00645         memcpy(p, buffer + buffer_len, hlens[i]);
00646         p += hlens[i];
00647         buffer_len += hlens[i];
00648     }
00649 
00650     return p - *out;
00651 }
00652 
00653 static float get_floor_average(vorbis_enc_floor * fc, float *coeffs, int i)
00654 {
00655     int begin = fc->list[fc->list[FFMAX(i-1, 0)].sort].x;
00656     int end   = fc->list[fc->list[FFMIN(i+1, fc->values - 1)].sort].x;
00657     int j;
00658     float average = 0;
00659 
00660     for (j = begin; j < end; j++)
00661         average += fabs(coeffs[j]);
00662     return average / (end - begin);
00663 }
00664 
00665 static void floor_fit(vorbis_enc_context *venc, vorbis_enc_floor *fc,
00666                       float *coeffs, uint_fast16_t *posts, int samples)
00667 {
00668     int range = 255 / fc->multiplier + 1;
00669     int i;
00670     float tot_average = 0.;
00671     float averages[fc->values];
00672     for (i = 0; i < fc->values; i++) {
00673         averages[i] = get_floor_average(fc, coeffs, i);
00674         tot_average += averages[i];
00675     }
00676     tot_average /= fc->values;
00677     tot_average /= venc->quality;
00678 
00679     for (i = 0; i < fc->values; i++) {
00680         int position  = fc->list[fc->list[i].sort].x;
00681         float average = averages[i];
00682         int j;
00683 
00684         average *= pow(tot_average / average, 0.5) * pow(1.25, position/200.); // MAGIC!
00685         for (j = 0; j < range - 1; j++)
00686             if (ff_vorbis_floor1_inverse_db_table[j * fc->multiplier] > average)
00687                 break;
00688         posts[fc->list[i].sort] = j;
00689     }
00690 }
00691 
00692 static int render_point(int x0, int y0, int x1, int y1, int x)
00693 {
00694     return y0 +  (x - x0) * (y1 - y0) / (x1 - x0);
00695 }
00696 
00697 static void floor_encode(vorbis_enc_context *venc, vorbis_enc_floor *fc,
00698                          PutBitContext *pb, uint_fast16_t *posts,
00699                          float *floor, int samples)
00700 {
00701     int range = 255 / fc->multiplier + 1;
00702     int coded[fc->values]; // first 2 values are unused
00703     int i, counter;
00704 
00705     put_bits(pb, 1, 1); // non zero
00706     put_bits(pb, ilog(range - 1), posts[0]);
00707     put_bits(pb, ilog(range - 1), posts[1]);
00708     coded[0] = coded[1] = 1;
00709 
00710     for (i = 2; i < fc->values; i++) {
00711         int predicted = render_point(fc->list[fc->list[i].low].x,
00712                                      posts[fc->list[i].low],
00713                                      fc->list[fc->list[i].high].x,
00714                                      posts[fc->list[i].high],
00715                                      fc->list[i].x);
00716         int highroom = range - predicted;
00717         int lowroom = predicted;
00718         int room = FFMIN(highroom, lowroom);
00719         if (predicted == posts[i]) {
00720             coded[i] = 0; // must be used later as flag!
00721             continue;
00722         } else {
00723             if (!coded[fc->list[i].low ])
00724                 coded[fc->list[i].low ] = -1;
00725             if (!coded[fc->list[i].high])
00726                 coded[fc->list[i].high] = -1;
00727         }
00728         if (posts[i] > predicted) {
00729             if (posts[i] - predicted > room)
00730                 coded[i] = posts[i] - predicted + lowroom;
00731             else
00732                 coded[i] = (posts[i] - predicted) << 1;
00733         } else {
00734             if (predicted - posts[i] > room)
00735                 coded[i] = predicted - posts[i] + highroom - 1;
00736             else
00737                 coded[i] = ((predicted - posts[i]) << 1) - 1;
00738         }
00739     }
00740 
00741     counter = 2;
00742     for (i = 0; i < fc->partitions; i++) {
00743         vorbis_enc_floor_class * c = &fc->classes[fc->partition_to_class[i]];
00744         int k, cval = 0, csub = 1<<c->subclass;
00745         if (c->subclass) {
00746             vorbis_enc_codebook * book = &venc->codebooks[c->masterbook];
00747             int cshift = 0;
00748             for (k = 0; k < c->dim; k++) {
00749                 int l;
00750                 for (l = 0; l < csub; l++) {
00751                     int maxval = 1;
00752                     if (c->books[l] != -1)
00753                         maxval = venc->codebooks[c->books[l]].nentries;
00754                     // coded could be -1, but this still works, cause that is 0
00755                     if (coded[counter + k] < maxval)
00756                         break;
00757                 }
00758                 assert(l != csub);
00759                 cval   |= l << cshift;
00760                 cshift += c->subclass;
00761             }
00762             put_codeword(pb, book, cval);
00763         }
00764         for (k = 0; k < c->dim; k++) {
00765             int book  = c->books[cval & (csub-1)];
00766             int entry = coded[counter++];
00767             cval >>= c->subclass;
00768             if (book == -1)
00769                 continue;
00770             if (entry == -1)
00771                 entry = 0;
00772             put_codeword(pb, &venc->codebooks[book], entry);
00773         }
00774     }
00775 
00776     ff_vorbis_floor1_render_list(fc->list, fc->values, posts, coded,
00777                                  fc->multiplier, floor, samples);
00778 }
00779 
00780 static float *put_vector(vorbis_enc_codebook *book, PutBitContext *pb,
00781                          float *num)
00782 {
00783     int i, entry = -1;
00784     float distance = FLT_MAX;
00785     assert(book->dimentions);
00786     for (i = 0; i < book->nentries; i++) {
00787         float * vec = book->dimentions + i * book->ndimentions, d = book->pow2[i];
00788         int j;
00789         if (!book->lens[i])
00790             continue;
00791         for (j = 0; j < book->ndimentions; j++)
00792             d -= vec[j] * num[j];
00793         if (distance > d) {
00794             entry    = i;
00795             distance = d;
00796         }
00797     }
00798     put_codeword(pb, book, entry);
00799     return &book->dimentions[entry * book->ndimentions];
00800 }
00801 
00802 static void residue_encode(vorbis_enc_context *venc, vorbis_enc_residue *rc,
00803                            PutBitContext *pb, float *coeffs, int samples,
00804                            int real_ch)
00805 {
00806     int pass, i, j, p, k;
00807     int psize      = rc->partition_size;
00808     int partitions = (rc->end - rc->begin) / psize;
00809     int channels   = (rc->type == 2) ? 1 : real_ch;
00810     int classes[channels][partitions];
00811     int classwords = venc->codebooks[rc->classbook].ndimentions;
00812 
00813     assert(rc->type == 2);
00814     assert(real_ch == 2);
00815     for (p = 0; p < partitions; p++) {
00816         float max1 = 0., max2 = 0.;
00817         int s = rc->begin + p * psize;
00818         for (k = s; k < s + psize; k += 2) {
00819             max1 = FFMAX(max1, fabs(coeffs[          k / real_ch]));
00820             max2 = FFMAX(max2, fabs(coeffs[samples + k / real_ch]));
00821         }
00822 
00823         for (i = 0; i < rc->classifications - 1; i++)
00824             if (max1 < rc->maxes[i][0] && max2 < rc->maxes[i][1])
00825                 break;
00826         classes[0][p] = i;
00827     }
00828 
00829     for (pass = 0; pass < 8; pass++) {
00830         p = 0;
00831         while (p < partitions) {
00832             if (pass == 0)
00833                 for (j = 0; j < channels; j++) {
00834                     vorbis_enc_codebook * book = &venc->codebooks[rc->classbook];
00835                     int entry = 0;
00836                     for (i = 0; i < classwords; i++) {
00837                         entry *= rc->classifications;
00838                         entry += classes[j][p + i];
00839                     }
00840                     put_codeword(pb, book, entry);
00841                 }
00842             for (i = 0; i < classwords && p < partitions; i++, p++) {
00843                 for (j = 0; j < channels; j++) {
00844                     int nbook = rc->books[classes[j][p]][pass];
00845                     vorbis_enc_codebook * book = &venc->codebooks[nbook];
00846                     float *buf = coeffs + samples*j + rc->begin + p*psize;
00847                     if (nbook == -1)
00848                         continue;
00849 
00850                     assert(rc->type == 0 || rc->type == 2);
00851                     assert(!(psize % book->ndimentions));
00852 
00853                     if (rc->type == 0) {
00854                         for (k = 0; k < psize; k += book->ndimentions) {
00855                             float *a = put_vector(book, pb, &buf[k]);
00856                             int l;
00857                             for (l = 0; l < book->ndimentions; l++)
00858                                 buf[k + l] -= a[l];
00859                         }
00860                     } else {
00861                         int s = rc->begin + p * psize, a1, b1;
00862                         a1 = (s % real_ch) * samples;
00863                         b1 =  s / real_ch;
00864                         s  = real_ch * samples;
00865                         for (k = 0; k < psize; k += book->ndimentions) {
00866                             int dim, a2 = a1, b2 = b1;
00867                             float vec[book->ndimentions], *pv = vec;
00868                             for (dim = book->ndimentions; dim--; ) {
00869                                 *pv++ = coeffs[a2 + b2];
00870                                 if ((a2 += samples) == s) {
00871                                     a2 = 0;
00872                                     b2++;
00873                                 }
00874                             }
00875                             pv = put_vector(book, pb, vec);
00876                             for (dim = book->ndimentions; dim--; ) {
00877                                 coeffs[a1 + b1] -= *pv++;
00878                                 if ((a1 += samples) == s) {
00879                                     a1 = 0;
00880                                     b1++;
00881                                 }
00882                             }
00883                         }
00884                     }
00885                 }
00886             }
00887         }
00888     }
00889 }
00890 
00891 static int apply_window_and_mdct(vorbis_enc_context *venc, signed short *audio,
00892                                  int samples)
00893 {
00894     int i, j, channel;
00895     const float * win = venc->win[0];
00896     int window_len = 1 << (venc->log2_blocksize[0] - 1);
00897     float n = (float)(1 << venc->log2_blocksize[0]) / 4.;
00898     // FIXME use dsp
00899 
00900     if (!venc->have_saved && !samples)
00901         return 0;
00902 
00903     if (venc->have_saved) {
00904         for (channel = 0; channel < venc->channels; channel++)
00905             memcpy(venc->samples + channel * window_len * 2,
00906                    venc->saved + channel * window_len, sizeof(float) * window_len);
00907     } else {
00908         for (channel = 0; channel < venc->channels; channel++)
00909             memset(venc->samples + channel * window_len * 2, 0,
00910                    sizeof(float) * window_len);
00911     }
00912 
00913     if (samples) {
00914         for (channel = 0; channel < venc->channels; channel++) {
00915             float * offset = venc->samples + channel*window_len*2 + window_len;
00916             j = channel;
00917             for (i = 0; i < samples; i++, j += venc->channels)
00918                 offset[i] = -audio[j] / 32768. / n * win[window_len - i - 1]; //FIXME find out why the sign has to be fliped
00919         }
00920     } else {
00921         for (channel = 0; channel < venc->channels; channel++)
00922             memset(venc->samples + channel * window_len * 2 + window_len,
00923                    0, sizeof(float) * window_len);
00924     }
00925 
00926     for (channel = 0; channel < venc->channels; channel++)
00927         ff_mdct_calc(&venc->mdct[0], venc->coeffs + channel * window_len,
00928                      venc->samples + channel * window_len * 2);
00929 
00930     if (samples) {
00931         for (channel = 0; channel < venc->channels; channel++) {
00932             float *offset = venc->saved + channel * window_len;
00933             j = channel;
00934             for (i = 0; i < samples; i++, j += venc->channels)
00935                 offset[i] = -audio[j] / 32768. / n * win[i]; //FIXME find out why the sign has to be fliped
00936         }
00937         venc->have_saved = 1;
00938     } else {
00939         venc->have_saved = 0;
00940     }
00941     return 1;
00942 }
00943 
00944 static av_cold int vorbis_encode_init(AVCodecContext *avccontext)
00945 {
00946     vorbis_enc_context *venc = avccontext->priv_data;
00947 
00948     if (avccontext->channels != 2) {
00949         av_log(avccontext, AV_LOG_ERROR, "Current FFmpeg Vorbis encoder only supports 2 channels.\n");
00950         return -1;
00951     }
00952 
00953     create_vorbis_context(venc, avccontext);
00954 
00955     if (avccontext->flags & CODEC_FLAG_QSCALE)
00956         venc->quality = avccontext->global_quality / (float)FF_QP2LAMBDA / 10.;
00957     else
00958         venc->quality = 1.;
00959     venc->quality *= venc->quality;
00960 
00961     avccontext->extradata_size = put_main_header(venc, (uint8_t**)&avccontext->extradata);
00962 
00963     avccontext->frame_size     = 1 << (venc->log2_blocksize[0] - 1);
00964 
00965     avccontext->coded_frame            = avcodec_alloc_frame();
00966     avccontext->coded_frame->key_frame = 1;
00967 
00968     return 0;
00969 }
00970 
00971 static int vorbis_encode_frame(AVCodecContext *avccontext,
00972                                unsigned char *packets,
00973                                int buf_size, void *data)
00974 {
00975     vorbis_enc_context *venc = avccontext->priv_data;
00976     signed short *audio = data;
00977     int samples = data ? avccontext->frame_size : 0;
00978     vorbis_enc_mode *mode;
00979     vorbis_enc_mapping *mapping;
00980     PutBitContext pb;
00981     int i;
00982 
00983     if (!apply_window_and_mdct(venc, audio, samples))
00984         return 0;
00985     samples = 1 << (venc->log2_blocksize[0] - 1);
00986 
00987     init_put_bits(&pb, packets, buf_size);
00988 
00989     put_bits(&pb, 1, 0); // magic bit
00990 
00991     put_bits(&pb, ilog(venc->nmodes - 1), 0); // 0 bits, the mode
00992 
00993     mode    = &venc->modes[0];
00994     mapping = &venc->mappings[mode->mapping];
00995     if (mode->blockflag) {
00996         put_bits(&pb, 1, 0);
00997         put_bits(&pb, 1, 0);
00998     }
00999 
01000     for (i = 0; i < venc->channels; i++) {
01001         vorbis_enc_floor *fc = &venc->floors[mapping->floor[mapping->mux[i]]];
01002         uint_fast16_t posts[fc->values];
01003         floor_fit(venc, fc, &venc->coeffs[i * samples], posts, samples);
01004         floor_encode(venc, fc, &pb, posts, &venc->floor[i * samples], samples);
01005     }
01006 
01007     for (i = 0; i < venc->channels * samples; i++)
01008         venc->coeffs[i] /= venc->floor[i];
01009 
01010     for (i = 0; i < mapping->coupling_steps; i++) {
01011         float *mag = venc->coeffs + mapping->magnitude[i] * samples;
01012         float *ang = venc->coeffs + mapping->angle[i]     * samples;
01013         int j;
01014         for (j = 0; j < samples; j++) {
01015             float a = ang[j];
01016             ang[j] -= mag[j];
01017             if (mag[j] > 0)
01018                 ang[j] = -ang[j];
01019             if (ang[j] < 0)
01020                 mag[j] = a;
01021         }
01022     }
01023 
01024     residue_encode(venc, &venc->residues[mapping->residue[mapping->mux[0]]],
01025                    &pb, venc->coeffs, samples, venc->channels);
01026 
01027     avccontext->coded_frame->pts = venc->sample_count;
01028     venc->sample_count += avccontext->frame_size;
01029     flush_put_bits(&pb);
01030     return put_bits_count(&pb) >> 3;
01031 }
01032 
01033 
01034 static av_cold int vorbis_encode_close(AVCodecContext *avccontext)
01035 {
01036     vorbis_enc_context *venc = avccontext->priv_data;
01037     int i;
01038 
01039     if (venc->codebooks)
01040         for (i = 0; i < venc->ncodebooks; i++) {
01041             av_freep(&venc->codebooks[i].lens);
01042             av_freep(&venc->codebooks[i].codewords);
01043             av_freep(&venc->codebooks[i].quantlist);
01044             av_freep(&venc->codebooks[i].dimentions);
01045             av_freep(&venc->codebooks[i].pow2);
01046         }
01047     av_freep(&venc->codebooks);
01048 
01049     if (venc->floors)
01050         for (i = 0; i < venc->nfloors; i++) {
01051             int j;
01052             if (venc->floors[i].classes)
01053                 for (j = 0; j < venc->floors[i].nclasses; j++)
01054                     av_freep(&venc->floors[i].classes[j].books);
01055             av_freep(&venc->floors[i].classes);
01056             av_freep(&venc->floors[i].partition_to_class);
01057             av_freep(&venc->floors[i].list);
01058         }
01059     av_freep(&venc->floors);
01060 
01061     if (venc->residues)
01062         for (i = 0; i < venc->nresidues; i++) {
01063             av_freep(&venc->residues[i].books);
01064             av_freep(&venc->residues[i].maxes);
01065         }
01066     av_freep(&venc->residues);
01067 
01068     if (venc->mappings)
01069         for (i = 0; i < venc->nmappings; i++) {
01070             av_freep(&venc->mappings[i].mux);
01071             av_freep(&venc->mappings[i].floor);
01072             av_freep(&venc->mappings[i].residue);
01073             av_freep(&venc->mappings[i].magnitude);
01074             av_freep(&venc->mappings[i].angle);
01075         }
01076     av_freep(&venc->mappings);
01077 
01078     av_freep(&venc->modes);
01079 
01080     av_freep(&venc->saved);
01081     av_freep(&venc->samples);
01082     av_freep(&venc->floor);
01083     av_freep(&venc->coeffs);
01084 
01085     ff_mdct_end(&venc->mdct[0]);
01086     ff_mdct_end(&venc->mdct[1]);
01087 
01088     av_freep(&avccontext->coded_frame);
01089     av_freep(&avccontext->extradata);
01090 
01091     return 0 ;
01092 }
01093 
01094 AVCodec vorbis_encoder = {
01095     "vorbis",
01096     AVMEDIA_TYPE_AUDIO,
01097     CODEC_ID_VORBIS,
01098     sizeof(vorbis_enc_context),
01099     vorbis_encode_init,
01100     vorbis_encode_frame,
01101     vorbis_encode_close,
01102     .capabilities= CODEC_CAP_DELAY | CODEC_CAP_EXPERIMENTAL,
01103     .sample_fmts = (const enum SampleFormat[]){SAMPLE_FMT_S16,SAMPLE_FMT_NONE},
01104     .long_name = NULL_IF_CONFIG_SMALL("Vorbis"),
01105 };

Generated on Fri Sep 16 2011 17:17:45 for FFmpeg by  doxygen 1.7.1