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00029 #include <stdint.h>
00030
00031
00032
00033
00034 static void scale_coefficients(AC3EncodeContext *s);
00035
00036 static void apply_window(DSPContext *dsp, SampleType *output,
00037 const SampleType *input, const SampleType *window,
00038 unsigned int len);
00039
00040 static int normalize_samples(AC3EncodeContext *s);
00041
00042 static void clip_coefficients(DSPContext *dsp, CoefType *coef, unsigned int len);
00043
00044 static CoefType calc_cpl_coord(CoefSumType energy_ch, CoefSumType energy_cpl);
00045
00046
00047 int AC3_NAME(allocate_sample_buffers)(AC3EncodeContext *s)
00048 {
00049 int ch;
00050
00051 FF_ALLOC_OR_GOTO(s->avctx, s->windowed_samples, AC3_WINDOW_SIZE *
00052 sizeof(*s->windowed_samples), alloc_fail);
00053 FF_ALLOC_OR_GOTO(s->avctx, s->planar_samples, s->channels * sizeof(*s->planar_samples),
00054 alloc_fail);
00055 for (ch = 0; ch < s->channels; ch++) {
00056 FF_ALLOCZ_OR_GOTO(s->avctx, s->planar_samples[ch],
00057 (AC3_FRAME_SIZE+AC3_BLOCK_SIZE) * sizeof(**s->planar_samples),
00058 alloc_fail);
00059 }
00060
00061 return 0;
00062 alloc_fail:
00063 return AVERROR(ENOMEM);
00064 }
00065
00066
00067
00068
00069
00070
00071 static void deinterleave_input_samples(AC3EncodeContext *s,
00072 const SampleType *samples)
00073 {
00074 int ch, i;
00075
00076
00077 for (ch = 0; ch < s->channels; ch++) {
00078 const SampleType *sptr;
00079 int sinc;
00080
00081
00082 memcpy(&s->planar_samples[ch][0], &s->planar_samples[ch][AC3_BLOCK_SIZE * s->num_blocks],
00083 AC3_BLOCK_SIZE * sizeof(s->planar_samples[0][0]));
00084
00085
00086 sinc = s->channels;
00087 sptr = samples + s->channel_map[ch];
00088 for (i = AC3_BLOCK_SIZE; i < AC3_BLOCK_SIZE * (s->num_blocks + 1); i++) {
00089 s->planar_samples[ch][i] = *sptr;
00090 sptr += sinc;
00091 }
00092 }
00093 }
00094
00095
00096
00097
00098
00099
00100
00101 static void apply_mdct(AC3EncodeContext *s)
00102 {
00103 int blk, ch;
00104
00105 for (ch = 0; ch < s->channels; ch++) {
00106 for (blk = 0; blk < s->num_blocks; blk++) {
00107 AC3Block *block = &s->blocks[blk];
00108 const SampleType *input_samples = &s->planar_samples[ch][blk * AC3_BLOCK_SIZE];
00109
00110 apply_window(&s->dsp, s->windowed_samples, input_samples,
00111 s->mdct_window, AC3_WINDOW_SIZE);
00112
00113 if (s->fixed_point)
00114 block->coeff_shift[ch+1] = normalize_samples(s);
00115
00116 s->mdct.mdct_calcw(&s->mdct, block->mdct_coef[ch+1],
00117 s->windowed_samples);
00118 }
00119 }
00120 }
00121
00122
00123
00124
00125
00126 static void apply_channel_coupling(AC3EncodeContext *s)
00127 {
00128 LOCAL_ALIGNED_16(CoefType, cpl_coords, [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
00129 #if CONFIG_AC3ENC_FLOAT
00130 LOCAL_ALIGNED_16(int32_t, fixed_cpl_coords, [AC3_MAX_BLOCKS], [AC3_MAX_CHANNELS][16]);
00131 #else
00132 int32_t (*fixed_cpl_coords)[AC3_MAX_CHANNELS][16] = cpl_coords;
00133 #endif
00134 int blk, ch, bnd, i, j;
00135 CoefSumType energy[AC3_MAX_BLOCKS][AC3_MAX_CHANNELS][16] = {{{0}}};
00136 int cpl_start, num_cpl_coefs;
00137
00138 memset(cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
00139 #if CONFIG_AC3ENC_FLOAT
00140 memset(fixed_cpl_coords, 0, AC3_MAX_BLOCKS * sizeof(*cpl_coords));
00141 #endif
00142
00143
00144
00145 cpl_start = s->start_freq[CPL_CH] - 1;
00146 num_cpl_coefs = FFALIGN(s->num_cpl_subbands * 12 + 1, 32);
00147 cpl_start = FFMIN(256, cpl_start + num_cpl_coefs) - num_cpl_coefs;
00148
00149
00150 for (blk = 0; blk < s->num_blocks; blk++) {
00151 AC3Block *block = &s->blocks[blk];
00152 CoefType *cpl_coef = &block->mdct_coef[CPL_CH][cpl_start];
00153 if (!block->cpl_in_use)
00154 continue;
00155 memset(cpl_coef, 0, num_cpl_coefs * sizeof(*cpl_coef));
00156 for (ch = 1; ch <= s->fbw_channels; ch++) {
00157 CoefType *ch_coef = &block->mdct_coef[ch][cpl_start];
00158 if (!block->channel_in_cpl[ch])
00159 continue;
00160 for (i = 0; i < num_cpl_coefs; i++)
00161 cpl_coef[i] += ch_coef[i];
00162 }
00163
00164
00165 clip_coefficients(&s->dsp, cpl_coef, num_cpl_coefs);
00166 }
00167
00168
00169
00170 bnd = 0;
00171 i = s->start_freq[CPL_CH];
00172 while (i < s->cpl_end_freq) {
00173 int band_size = s->cpl_band_sizes[bnd];
00174 for (ch = CPL_CH; ch <= s->fbw_channels; ch++) {
00175 for (blk = 0; blk < s->num_blocks; blk++) {
00176 AC3Block *block = &s->blocks[blk];
00177 if (!block->cpl_in_use || (ch > CPL_CH && !block->channel_in_cpl[ch]))
00178 continue;
00179 for (j = 0; j < band_size; j++) {
00180 CoefType v = block->mdct_coef[ch][i+j];
00181 MAC_COEF(energy[blk][ch][bnd], v, v);
00182 }
00183 }
00184 }
00185 i += band_size;
00186 bnd++;
00187 }
00188
00189
00190 for (blk = 0; blk < s->num_blocks; blk++) {
00191 AC3Block *block = &s->blocks[blk];
00192 if (!block->cpl_in_use)
00193 continue;
00194 for (ch = 1; ch <= s->fbw_channels; ch++) {
00195 if (!block->channel_in_cpl[ch])
00196 continue;
00197 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
00198 cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy[blk][ch][bnd],
00199 energy[blk][CPL_CH][bnd]);
00200 }
00201 }
00202 }
00203
00204
00205 for (blk = 0; blk < s->num_blocks; blk++) {
00206 AC3Block *block = &s->blocks[blk];
00207 AC3Block *block0 = blk ? &s->blocks[blk-1] : NULL;
00208
00209 memset(block->new_cpl_coords, 0, sizeof(block->new_cpl_coords));
00210
00211 if (block->cpl_in_use) {
00212
00213
00214
00215
00216
00217 if (blk == 0 || !block0->cpl_in_use) {
00218 for (ch = 1; ch <= s->fbw_channels; ch++)
00219 block->new_cpl_coords[ch] = 1;
00220 } else {
00221 for (ch = 1; ch <= s->fbw_channels; ch++) {
00222 if (!block->channel_in_cpl[ch])
00223 continue;
00224 if (!block0->channel_in_cpl[ch]) {
00225 block->new_cpl_coords[ch] = 1;
00226 } else {
00227 CoefSumType coord_diff = 0;
00228 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
00229 coord_diff += FFABS(cpl_coords[blk-1][ch][bnd] -
00230 cpl_coords[blk ][ch][bnd]);
00231 }
00232 coord_diff /= s->num_cpl_bands;
00233 if (coord_diff > NEW_CPL_COORD_THRESHOLD)
00234 block->new_cpl_coords[ch] = 1;
00235 }
00236 }
00237 }
00238 }
00239 }
00240
00241
00242
00243 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
00244 blk = 0;
00245 while (blk < s->num_blocks) {
00246 int av_uninit(blk1);
00247 AC3Block *block = &s->blocks[blk];
00248
00249 if (!block->cpl_in_use) {
00250 blk++;
00251 continue;
00252 }
00253
00254 for (ch = 1; ch <= s->fbw_channels; ch++) {
00255 CoefSumType energy_ch, energy_cpl;
00256 if (!block->channel_in_cpl[ch])
00257 continue;
00258 energy_cpl = energy[blk][CPL_CH][bnd];
00259 energy_ch = energy[blk][ch][bnd];
00260 blk1 = blk+1;
00261 while (!s->blocks[blk1].new_cpl_coords[ch] && blk1 < s->num_blocks) {
00262 if (s->blocks[blk1].cpl_in_use) {
00263 energy_cpl += energy[blk1][CPL_CH][bnd];
00264 energy_ch += energy[blk1][ch][bnd];
00265 }
00266 blk1++;
00267 }
00268 cpl_coords[blk][ch][bnd] = calc_cpl_coord(energy_ch, energy_cpl);
00269 }
00270 blk = blk1;
00271 }
00272 }
00273
00274
00275 for (blk = 0; blk < s->num_blocks; blk++) {
00276 AC3Block *block = &s->blocks[blk];
00277 if (!block->cpl_in_use)
00278 continue;
00279
00280 #if CONFIG_AC3ENC_FLOAT
00281 s->ac3dsp.float_to_fixed24(fixed_cpl_coords[blk][1],
00282 cpl_coords[blk][1],
00283 s->fbw_channels * 16);
00284 #endif
00285 s->ac3dsp.extract_exponents(block->cpl_coord_exp[1],
00286 fixed_cpl_coords[blk][1],
00287 s->fbw_channels * 16);
00288
00289 for (ch = 1; ch <= s->fbw_channels; ch++) {
00290 int bnd, min_exp, max_exp, master_exp;
00291
00292 if (!block->new_cpl_coords[ch])
00293 continue;
00294
00295
00296 min_exp = max_exp = block->cpl_coord_exp[ch][0];
00297 for (bnd = 1; bnd < s->num_cpl_bands; bnd++) {
00298 int exp = block->cpl_coord_exp[ch][bnd];
00299 min_exp = FFMIN(exp, min_exp);
00300 max_exp = FFMAX(exp, max_exp);
00301 }
00302 master_exp = ((max_exp - 15) + 2) / 3;
00303 master_exp = FFMAX(master_exp, 0);
00304 while (min_exp < master_exp * 3)
00305 master_exp--;
00306 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
00307 block->cpl_coord_exp[ch][bnd] = av_clip(block->cpl_coord_exp[ch][bnd] -
00308 master_exp * 3, 0, 15);
00309 }
00310 block->cpl_master_exp[ch] = master_exp;
00311
00312
00313 for (bnd = 0; bnd < s->num_cpl_bands; bnd++) {
00314 int cpl_exp = block->cpl_coord_exp[ch][bnd];
00315 int cpl_mant = (fixed_cpl_coords[blk][ch][bnd] << (5 + cpl_exp + master_exp * 3)) >> 24;
00316 if (cpl_exp == 15)
00317 cpl_mant >>= 1;
00318 else
00319 cpl_mant -= 16;
00320
00321 block->cpl_coord_mant[ch][bnd] = cpl_mant;
00322 }
00323 }
00324 }
00325
00326 if (CONFIG_EAC3_ENCODER && s->eac3)
00327 ff_eac3_set_cpl_states(s);
00328 }
00329
00330
00331
00332
00333
00334 static void compute_rematrixing_strategy(AC3EncodeContext *s)
00335 {
00336 int nb_coefs;
00337 int blk, bnd, i;
00338 AC3Block *block, *av_uninit(block0);
00339
00340 if (s->channel_mode != AC3_CHMODE_STEREO)
00341 return;
00342
00343 for (blk = 0; blk < s->num_blocks; blk++) {
00344 block = &s->blocks[blk];
00345 block->new_rematrixing_strategy = !blk;
00346
00347 block->num_rematrixing_bands = 4;
00348 if (block->cpl_in_use) {
00349 block->num_rematrixing_bands -= (s->start_freq[CPL_CH] <= 61);
00350 block->num_rematrixing_bands -= (s->start_freq[CPL_CH] == 37);
00351 if (blk && block->num_rematrixing_bands != block0->num_rematrixing_bands)
00352 block->new_rematrixing_strategy = 1;
00353 }
00354 nb_coefs = FFMIN(block->end_freq[1], block->end_freq[2]);
00355
00356 if (!s->rematrixing_enabled) {
00357 block0 = block;
00358 continue;
00359 }
00360
00361 for (bnd = 0; bnd < block->num_rematrixing_bands; bnd++) {
00362
00363 int start = ff_ac3_rematrix_band_tab[bnd];
00364 int end = FFMIN(nb_coefs, ff_ac3_rematrix_band_tab[bnd+1]);
00365 CoefSumType sum[4] = {0,};
00366 for (i = start; i < end; i++) {
00367 CoefType lt = block->mdct_coef[1][i];
00368 CoefType rt = block->mdct_coef[2][i];
00369 CoefType md = lt + rt;
00370 CoefType sd = lt - rt;
00371 MAC_COEF(sum[0], lt, lt);
00372 MAC_COEF(sum[1], rt, rt);
00373 MAC_COEF(sum[2], md, md);
00374 MAC_COEF(sum[3], sd, sd);
00375 }
00376
00377
00378 if (FFMIN(sum[2], sum[3]) < FFMIN(sum[0], sum[1]))
00379 block->rematrixing_flags[bnd] = 1;
00380 else
00381 block->rematrixing_flags[bnd] = 0;
00382
00383
00384 if (blk &&
00385 block->rematrixing_flags[bnd] != block0->rematrixing_flags[bnd]) {
00386 block->new_rematrixing_strategy = 1;
00387 }
00388 }
00389 block0 = block;
00390 }
00391 }
00392
00393
00394 int AC3_NAME(encode_frame)(AVCodecContext *avctx, unsigned char *frame,
00395 int buf_size, void *data)
00396 {
00397 AC3EncodeContext *s = avctx->priv_data;
00398 const SampleType *samples = data;
00399 int ret;
00400
00401 if (s->options.allow_per_frame_metadata) {
00402 ret = ff_ac3_validate_metadata(s);
00403 if (ret)
00404 return ret;
00405 }
00406
00407 if (s->bit_alloc.sr_code == 1 || s->eac3)
00408 ff_ac3_adjust_frame_size(s);
00409
00410 deinterleave_input_samples(s, samples);
00411
00412 apply_mdct(s);
00413
00414 if (s->fixed_point)
00415 scale_coefficients(s);
00416
00417 clip_coefficients(&s->dsp, s->blocks[0].mdct_coef[1],
00418 AC3_MAX_COEFS * s->num_blocks * s->channels);
00419
00420 s->cpl_on = s->cpl_enabled;
00421 ff_ac3_compute_coupling_strategy(s);
00422
00423 if (s->cpl_on)
00424 apply_channel_coupling(s);
00425
00426 compute_rematrixing_strategy(s);
00427
00428 if (!s->fixed_point)
00429 scale_coefficients(s);
00430
00431 ff_ac3_apply_rematrixing(s);
00432
00433 ff_ac3_process_exponents(s);
00434
00435 ret = ff_ac3_compute_bit_allocation(s);
00436 if (ret) {
00437 av_log(avctx, AV_LOG_ERROR, "Bit allocation failed. Try increasing the bitrate.\n");
00438 return ret;
00439 }
00440
00441 ff_ac3_group_exponents(s);
00442
00443 ff_ac3_quantize_mantissas(s);
00444
00445 ff_ac3_output_frame(s, frame);
00446
00447 return s->frame_size;
00448 }