3 * Copyright (c) 2002-2007 The Libav Project
5 * This file is part of Libav.
7 * Libav is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * Libav is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with Libav; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
30 /* XXX: use same run/length optimization as mpeg decoders */
31 //FIXME maybe split decode / encode or pass flag
32 static void init_coef_vlc(VLC *vlc, uint16_t **prun_table,
33 float **plevel_table, uint16_t **pint_table,
34 const CoefVLCTable *vlc_table)
37 const uint8_t *table_bits = vlc_table->huffbits;
38 const uint32_t *table_codes = vlc_table->huffcodes;
39 const uint16_t *levels_table = vlc_table->levels;
40 uint16_t *run_table, *level_table, *int_table;
42 int i, l, j, k, level;
44 init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0);
46 run_table = av_malloc(n * sizeof(uint16_t));
47 level_table = av_malloc(n * sizeof(uint16_t));
48 flevel_table= av_malloc(n * sizeof(*flevel_table));
49 int_table = av_malloc(n * sizeof(uint16_t));
55 l = levels_table[k++];
56 for (j = 0; j < l; j++) {
58 level_table[i] = level;
59 flevel_table[i]= level;
64 *prun_table = run_table;
65 *plevel_table = flevel_table;
66 *pint_table = int_table;
71 *@brief Get the samples per frame for this stream.
72 *@param sample_rate output sample_rate
73 *@param version wma version
74 *@param decode_flags codec compression features
75 *@return log2 of the number of output samples per frame
77 int av_cold ff_wma_get_frame_len_bits(int sample_rate, int version,
78 unsigned int decode_flags)
83 if (sample_rate <= 16000) {
85 } else if (sample_rate <= 22050 ||
86 (sample_rate <= 32000 && version == 1)) {
88 } else if (sample_rate <= 48000) {
90 } else if (sample_rate <= 96000) {
97 int tmp = decode_flags & 0x6;
100 } else if (tmp == 0x4) {
102 } else if (tmp == 0x6) {
107 return frame_len_bits;
110 int ff_wma_init(AVCodecContext *avctx, int flags2)
112 WMACodecContext *s = avctx->priv_data;
114 float bps1, high_freq;
119 if ( avctx->sample_rate <= 0 || avctx->sample_rate > 50000
120 || avctx->channels <= 0 || avctx->channels > 8
121 || avctx->bit_rate <= 0)
124 s->sample_rate = avctx->sample_rate;
125 s->nb_channels = avctx->channels;
126 s->bit_rate = avctx->bit_rate;
127 s->block_align = avctx->block_align;
129 dsputil_init(&s->dsp, avctx);
130 ff_fmt_convert_init(&s->fmt_conv, avctx);
132 if (avctx->codec->id == CODEC_ID_WMAV1) {
138 /* compute MDCT block size */
139 s->frame_len_bits = ff_wma_get_frame_len_bits(s->sample_rate, s->version, 0);
141 s->frame_len = 1 << s->frame_len_bits;
142 if (s->use_variable_block_len) {
144 nb = ((flags2 >> 3) & 3) + 1;
145 if ((s->bit_rate / s->nb_channels) >= 32000)
147 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
150 s->nb_block_sizes = nb + 1;
152 s->nb_block_sizes = 1;
155 /* init rate dependent parameters */
156 s->use_noise_coding = 1;
157 high_freq = s->sample_rate * 0.5;
159 /* if version 2, then the rates are normalized */
160 sample_rate1 = s->sample_rate;
161 if (s->version == 2) {
162 if (sample_rate1 >= 44100) {
163 sample_rate1 = 44100;
164 } else if (sample_rate1 >= 22050) {
165 sample_rate1 = 22050;
166 } else if (sample_rate1 >= 16000) {
167 sample_rate1 = 16000;
168 } else if (sample_rate1 >= 11025) {
169 sample_rate1 = 11025;
170 } else if (sample_rate1 >= 8000) {
175 bps = (float)s->bit_rate / (float)(s->nb_channels * s->sample_rate);
176 s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0 + 0.5)) + 2;
178 /* compute high frequency value and choose if noise coding should
181 if (s->nb_channels == 2)
183 if (sample_rate1 == 44100) {
185 s->use_noise_coding = 0;
187 high_freq = high_freq * 0.4;
189 } else if (sample_rate1 == 22050) {
191 s->use_noise_coding = 0;
192 } else if (bps1 >= 0.72) {
193 high_freq = high_freq * 0.7;
195 high_freq = high_freq * 0.6;
197 } else if (sample_rate1 == 16000) {
199 high_freq = high_freq * 0.5;
201 high_freq = high_freq * 0.3;
203 } else if (sample_rate1 == 11025) {
204 high_freq = high_freq * 0.7;
205 } else if (sample_rate1 == 8000) {
207 high_freq = high_freq * 0.5;
208 } else if (bps > 0.75) {
209 s->use_noise_coding = 0;
211 high_freq = high_freq * 0.65;
215 high_freq = high_freq * 0.75;
216 } else if (bps >= 0.6) {
217 high_freq = high_freq * 0.6;
219 high_freq = high_freq * 0.5;
222 av_dlog(s->avctx, "flags2=0x%x\n", flags2);
223 av_dlog(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
224 s->version, s->nb_channels, s->sample_rate, s->bit_rate,
226 av_dlog(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
227 bps, bps1, high_freq, s->byte_offset_bits);
228 av_dlog(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
229 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
231 /* compute the scale factor band sizes for each MDCT block size */
233 int a, b, pos, lpos, k, block_len, i, j, n;
234 const uint8_t *table;
236 if (s->version == 1) {
241 for (k = 0; k < s->nb_block_sizes; k++) {
242 block_len = s->frame_len >> k;
244 if (s->version == 1) {
246 for (i = 0; i < 25; i++) {
247 a = ff_wma_critical_freqs[i];
249 pos = ((block_len * 2 * a) + (b >> 1)) / b;
252 s->exponent_bands[0][i] = pos - lpos;
253 if (pos >= block_len) {
259 s->exponent_sizes[0] = i;
261 /* hardcoded tables */
263 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
265 if (s->sample_rate >= 44100) {
266 table = exponent_band_44100[a];
267 } else if (s->sample_rate >= 32000) {
268 table = exponent_band_32000[a];
269 } else if (s->sample_rate >= 22050) {
270 table = exponent_band_22050[a];
275 for (i = 0; i < n; i++)
276 s->exponent_bands[k][i] = table[i];
277 s->exponent_sizes[k] = n;
281 for (i = 0; i < 25; i++) {
282 a = ff_wma_critical_freqs[i];
284 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
289 s->exponent_bands[k][j++] = pos - lpos;
290 if (pos >= block_len)
294 s->exponent_sizes[k] = j;
298 /* max number of coefs */
299 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
300 /* high freq computation */
301 s->high_band_start[k] = (int)((block_len * 2 * high_freq) /
302 s->sample_rate + 0.5);
303 n = s->exponent_sizes[k];
306 for (i = 0; i < n; i++) {
309 pos += s->exponent_bands[k][i];
311 if (start < s->high_band_start[k])
312 start = s->high_band_start[k];
313 if (end > s->coefs_end[k])
314 end = s->coefs_end[k];
316 s->exponent_high_bands[k][j++] = end - start;
318 s->exponent_high_sizes[k] = j;
320 tprintf(s->avctx, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
323 s->high_band_start[k],
324 s->exponent_high_sizes[k]);
325 for (j = 0; j < s->exponent_high_sizes[k]; j++)
326 tprintf(s->avctx, " %d", s->exponent_high_bands[k][j]);
327 tprintf(s->avctx, "\n");
335 for (i = 0; i < s->nb_block_sizes; i++) {
336 tprintf(s->avctx, "%5d: n=%2d:",
338 s->exponent_sizes[i]);
339 for (j = 0; j < s->exponent_sizes[i]; j++)
340 tprintf(s->avctx, " %d", s->exponent_bands[i][j]);
341 tprintf(s->avctx, "\n");
346 /* init MDCT windows : simple sinus window */
347 for (i = 0; i < s->nb_block_sizes; i++) {
348 ff_init_ff_sine_windows(s->frame_len_bits - i);
349 s->windows[i] = ff_sine_windows[s->frame_len_bits - i];
352 s->reset_block_lengths = 1;
354 if (s->use_noise_coding) {
356 /* init the noise generator */
357 if (s->use_exp_vlc) {
358 s->noise_mult = 0.02;
360 s->noise_mult = 0.04;
364 for (i = 0; i < NOISE_TAB_SIZE; i++)
365 s->noise_table[i] = 1.0 * s->noise_mult;
371 norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult;
372 for (i = 0; i < NOISE_TAB_SIZE; i++) {
373 seed = seed * 314159 + 1;
374 s->noise_table[i] = (float)((int)seed) * norm;
380 /* choose the VLC tables for the coefficients */
382 if (s->sample_rate >= 32000) {
385 } else if (bps1 < 1.16) {
389 s->coef_vlcs[0]= &coef_vlcs[coef_vlc_table * 2 ];
390 s->coef_vlcs[1]= &coef_vlcs[coef_vlc_table * 2 + 1];
391 init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0], &s->int_table[0],
393 init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1], &s->int_table[1],
399 int ff_wma_total_gain_to_bits(int total_gain)
401 if (total_gain < 15) return 13;
402 else if (total_gain < 32) return 12;
403 else if (total_gain < 40) return 11;
404 else if (total_gain < 45) return 10;
408 int ff_wma_end(AVCodecContext *avctx)
410 WMACodecContext *s = avctx->priv_data;
413 for (i = 0; i < s->nb_block_sizes; i++)
414 ff_mdct_end(&s->mdct_ctx[i]);
416 if (s->use_exp_vlc) {
417 free_vlc(&s->exp_vlc);
419 if (s->use_noise_coding) {
420 free_vlc(&s->hgain_vlc);
422 for (i = 0; i < 2; i++) {
423 free_vlc(&s->coef_vlc[i]);
424 av_free(s->run_table[i]);
425 av_free(s->level_table[i]);
426 av_free(s->int_table[i]);
433 * Decode an uncompressed coefficient.
434 * @param gb GetBitContext
435 * @return the decoded coefficient
437 unsigned int ff_wma_get_large_val(GetBitContext* gb)
439 /** consumes up to 34 bits */
451 return get_bits_long(gb, n_bits);
455 * Decode run level compressed coefficients.
456 * @param avctx codec context
457 * @param gb bitstream reader context
458 * @param vlc vlc table for get_vlc2
459 * @param level_table level codes
460 * @param run_table run codes
461 * @param version 0 for wma1,2 1 for wmapro
462 * @param ptr output buffer
463 * @param offset offset in the output buffer
464 * @param num_coefs number of input coefficents
465 * @param block_len input buffer length (2^n)
466 * @param frame_len_bits number of bits for escaped run codes
467 * @param coef_nb_bits number of bits for escaped level codes
468 * @return 0 on success, -1 otherwise
470 int ff_wma_run_level_decode(AVCodecContext* avctx, GetBitContext* gb,
472 const float *level_table, const uint16_t *run_table,
473 int version, WMACoef *ptr, int offset,
474 int num_coefs, int block_len, int frame_len_bits,
477 int code, level, sign;
478 const uint32_t *ilvl = (const uint32_t*)level_table;
479 uint32_t *iptr = (uint32_t*)ptr;
480 const unsigned int coef_mask = block_len - 1;
481 for (; offset < num_coefs; offset++) {
482 code = get_vlc2(gb, vlc->table, VLCBITS, VLCMAX);
485 offset += run_table[code];
486 sign = get_bits1(gb) - 1;
487 iptr[offset & coef_mask] = ilvl[code] ^ sign<<31;
488 } else if (code == 1) {
494 level = get_bits(gb, coef_nb_bits);
495 /** NOTE: this is rather suboptimal. reading
496 block_len_bits would be better */
497 offset += get_bits(gb, frame_len_bits);
499 level = ff_wma_get_large_val(gb);
504 av_log(avctx,AV_LOG_ERROR,
505 "broken escape sequence\n");
508 offset += get_bits(gb, frame_len_bits) + 4;
510 offset += get_bits(gb, 2) + 1;
513 sign = get_bits1(gb) - 1;
514 ptr[offset & coef_mask] = (level^sign) - sign;
517 /** NOTE: EOB can be omitted */
518 if (offset > num_coefs) {
519 av_log(avctx, AV_LOG_ERROR, "overflow in spectral RLE, ignoring\n");