3 * Copyright (c) 2002-2007 The FFmpeg Project
5 * This file is part of FFmpeg.
7 * FFmpeg 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 * FFmpeg 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 FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
29 /* XXX: use same run/length optimization as mpeg decoders */
30 //FIXME maybe split decode / encode or pass flag
31 static void init_coef_vlc(VLC *vlc, uint16_t **prun_table,
32 float **plevel_table, uint16_t **pint_table,
33 const CoefVLCTable *vlc_table)
36 const uint8_t *table_bits = vlc_table->huffbits;
37 const uint32_t *table_codes = vlc_table->huffcodes;
38 const uint16_t *levels_table = vlc_table->levels;
39 uint16_t *run_table, *level_table, *int_table;
41 int i, l, j, k, level;
43 init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0);
45 run_table = av_malloc(n * sizeof(uint16_t));
46 level_table = av_malloc(n * sizeof(uint16_t));
47 flevel_table= av_malloc(n * sizeof(*flevel_table));
48 int_table = av_malloc(n * sizeof(uint16_t));
54 l = levels_table[k++];
55 for (j = 0; j < l; j++) {
57 level_table[i] = level;
58 flevel_table[i]= level;
63 *prun_table = run_table;
64 *plevel_table = flevel_table;
65 *pint_table = int_table;
70 *@brief Get the samples per frame for this stream.
71 *@param sample_rate output sample_rate
72 *@param version wma version
73 *@param decode_flags codec compression features
74 *@return log2 of the number of output samples per frame
76 int av_cold ff_wma_get_frame_len_bits(int sample_rate, int version,
77 unsigned int decode_flags)
82 if (sample_rate <= 16000) {
84 } else if (sample_rate <= 22050 ||
85 (sample_rate <= 32000 && version == 1)) {
87 } else if (sample_rate <= 48000) {
89 } else if (sample_rate <= 96000) {
96 int tmp = decode_flags & 0x6;
99 } else if (tmp == 0x4) {
101 } else if (tmp == 0x6) {
106 return frame_len_bits;
109 int ff_wma_init(AVCodecContext *avctx, int flags2)
111 WMACodecContext *s = avctx->priv_data;
113 float bps1, high_freq;
118 if ( avctx->sample_rate <= 0 || avctx->sample_rate > 50000
119 || avctx->channels <= 0 || avctx->channels > 8
120 || avctx->bit_rate <= 0)
123 s->sample_rate = avctx->sample_rate;
124 s->nb_channels = avctx->channels;
125 s->bit_rate = avctx->bit_rate;
126 s->block_align = avctx->block_align;
128 dsputil_init(&s->dsp, avctx);
130 if (avctx->codec->id == CODEC_ID_WMAV1) {
136 /* compute MDCT block size */
137 s->frame_len_bits = ff_wma_get_frame_len_bits(s->sample_rate, s->version, 0);
139 s->frame_len = 1 << s->frame_len_bits;
140 if (s->use_variable_block_len) {
142 nb = ((flags2 >> 3) & 3) + 1;
143 if ((s->bit_rate / s->nb_channels) >= 32000)
145 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
148 s->nb_block_sizes = nb + 1;
150 s->nb_block_sizes = 1;
153 /* init rate dependent parameters */
154 s->use_noise_coding = 1;
155 high_freq = s->sample_rate * 0.5;
157 /* if version 2, then the rates are normalized */
158 sample_rate1 = s->sample_rate;
159 if (s->version == 2) {
160 if (sample_rate1 >= 44100) {
161 sample_rate1 = 44100;
162 } else if (sample_rate1 >= 22050) {
163 sample_rate1 = 22050;
164 } else if (sample_rate1 >= 16000) {
165 sample_rate1 = 16000;
166 } else if (sample_rate1 >= 11025) {
167 sample_rate1 = 11025;
168 } else if (sample_rate1 >= 8000) {
173 bps = (float)s->bit_rate / (float)(s->nb_channels * s->sample_rate);
174 s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0 + 0.5)) + 2;
176 /* compute high frequency value and choose if noise coding should
179 if (s->nb_channels == 2)
181 if (sample_rate1 == 44100) {
183 s->use_noise_coding = 0;
185 high_freq = high_freq * 0.4;
187 } else if (sample_rate1 == 22050) {
189 s->use_noise_coding = 0;
190 } else if (bps1 >= 0.72) {
191 high_freq = high_freq * 0.7;
193 high_freq = high_freq * 0.6;
195 } else if (sample_rate1 == 16000) {
197 high_freq = high_freq * 0.5;
199 high_freq = high_freq * 0.3;
201 } else if (sample_rate1 == 11025) {
202 high_freq = high_freq * 0.7;
203 } else if (sample_rate1 == 8000) {
205 high_freq = high_freq * 0.5;
206 } else if (bps > 0.75) {
207 s->use_noise_coding = 0;
209 high_freq = high_freq * 0.65;
213 high_freq = high_freq * 0.75;
214 } else if (bps >= 0.6) {
215 high_freq = high_freq * 0.6;
217 high_freq = high_freq * 0.5;
220 dprintf(s->avctx, "flags2=0x%x\n", flags2);
221 dprintf(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
222 s->version, s->nb_channels, s->sample_rate, s->bit_rate,
224 dprintf(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
225 bps, bps1, high_freq, s->byte_offset_bits);
226 dprintf(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
227 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
229 /* compute the scale factor band sizes for each MDCT block size */
231 int a, b, pos, lpos, k, block_len, i, j, n;
232 const uint8_t *table;
234 if (s->version == 1) {
239 for (k = 0; k < s->nb_block_sizes; k++) {
240 block_len = s->frame_len >> k;
242 if (s->version == 1) {
244 for (i = 0; i < 25; i++) {
245 a = ff_wma_critical_freqs[i];
247 pos = ((block_len * 2 * a) + (b >> 1)) / b;
250 s->exponent_bands[0][i] = pos - lpos;
251 if (pos >= block_len) {
257 s->exponent_sizes[0] = i;
259 /* hardcoded tables */
261 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
263 if (s->sample_rate >= 44100) {
264 table = exponent_band_44100[a];
265 } else if (s->sample_rate >= 32000) {
266 table = exponent_band_32000[a];
267 } else if (s->sample_rate >= 22050) {
268 table = exponent_band_22050[a];
273 for (i = 0; i < n; i++)
274 s->exponent_bands[k][i] = table[i];
275 s->exponent_sizes[k] = n;
279 for (i = 0; i < 25; i++) {
280 a = ff_wma_critical_freqs[i];
282 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
287 s->exponent_bands[k][j++] = pos - lpos;
288 if (pos >= block_len)
292 s->exponent_sizes[k] = j;
296 /* max number of coefs */
297 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
298 /* high freq computation */
299 s->high_band_start[k] = (int)((block_len * 2 * high_freq) /
300 s->sample_rate + 0.5);
301 n = s->exponent_sizes[k];
304 for (i = 0; i < n; i++) {
307 pos += s->exponent_bands[k][i];
309 if (start < s->high_band_start[k])
310 start = s->high_band_start[k];
311 if (end > s->coefs_end[k])
312 end = s->coefs_end[k];
314 s->exponent_high_bands[k][j++] = end - start;
316 s->exponent_high_sizes[k] = j;
318 tprintf(s->avctx, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
321 s->high_band_start[k],
322 s->exponent_high_sizes[k]);
323 for (j = 0; j < s->exponent_high_sizes[k]; j++)
324 tprintf(s->avctx, " %d", s->exponent_high_bands[k][j]);
325 tprintf(s->avctx, "\n");
333 for (i = 0; i < s->nb_block_sizes; i++) {
334 tprintf(s->avctx, "%5d: n=%2d:",
336 s->exponent_sizes[i]);
337 for (j = 0; j < s->exponent_sizes[i]; j++)
338 tprintf(s->avctx, " %d", s->exponent_bands[i][j]);
339 tprintf(s->avctx, "\n");
344 /* init MDCT windows : simple sinus window */
345 for (i = 0; i < s->nb_block_sizes; i++) {
346 ff_init_ff_sine_windows(s->frame_len_bits - i);
347 s->windows[i] = ff_sine_windows[s->frame_len_bits - i];
350 s->reset_block_lengths = 1;
352 if (s->use_noise_coding) {
354 /* init the noise generator */
355 if (s->use_exp_vlc) {
356 s->noise_mult = 0.02;
358 s->noise_mult = 0.04;
362 for (i = 0; i < NOISE_TAB_SIZE; i++)
363 s->noise_table[i] = 1.0 * s->noise_mult;
369 norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult;
370 for (i = 0; i < NOISE_TAB_SIZE; i++) {
371 seed = seed * 314159 + 1;
372 s->noise_table[i] = (float)((int)seed) * norm;
378 /* choose the VLC tables for the coefficients */
380 if (s->sample_rate >= 32000) {
383 } else if (bps1 < 1.16) {
387 s->coef_vlcs[0]= &coef_vlcs[coef_vlc_table * 2 ];
388 s->coef_vlcs[1]= &coef_vlcs[coef_vlc_table * 2 + 1];
389 init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0], &s->int_table[0],
391 init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1], &s->int_table[1],
397 int ff_wma_total_gain_to_bits(int total_gain)
399 if (total_gain < 15) return 13;
400 else if (total_gain < 32) return 12;
401 else if (total_gain < 40) return 11;
402 else if (total_gain < 45) return 10;
406 int ff_wma_end(AVCodecContext *avctx)
408 WMACodecContext *s = avctx->priv_data;
411 for (i = 0; i < s->nb_block_sizes; i++)
412 ff_mdct_end(&s->mdct_ctx[i]);
414 if (s->use_exp_vlc) {
415 free_vlc(&s->exp_vlc);
417 if (s->use_noise_coding) {
418 free_vlc(&s->hgain_vlc);
420 for (i = 0; i < 2; i++) {
421 free_vlc(&s->coef_vlc[i]);
422 av_free(s->run_table[i]);
423 av_free(s->level_table[i]);
424 av_free(s->int_table[i]);
431 * Decode an uncompressed coefficient.
432 * @param gb GetBitContext
433 * @return the decoded coefficient
435 unsigned int ff_wma_get_large_val(GetBitContext* gb)
437 /** consumes up to 34 bits */
449 return get_bits_long(gb, n_bits);
453 * Decode run level compressed coefficients.
454 * @param avctx codec context
455 * @param gb bitstream reader context
456 * @param vlc vlc table for get_vlc2
457 * @param level_table level codes
458 * @param run_table run codes
459 * @param version 0 for wma1,2 1 for wmapro
460 * @param ptr output buffer
461 * @param offset offset in the output buffer
462 * @param num_coefs number of input coefficents
463 * @param block_len input buffer length (2^n)
464 * @param frame_len_bits number of bits for escaped run codes
465 * @param coef_nb_bits number of bits for escaped level codes
466 * @return 0 on success, -1 otherwise
468 int ff_wma_run_level_decode(AVCodecContext* avctx, GetBitContext* gb,
470 const float *level_table, const uint16_t *run_table,
471 int version, WMACoef *ptr, int offset,
472 int num_coefs, int block_len, int frame_len_bits,
475 int code, level, sign;
476 const uint32_t *ilvl = (const uint32_t*)level_table;
477 uint32_t *iptr = (uint32_t*)ptr;
478 const unsigned int coef_mask = block_len - 1;
479 for (; offset < num_coefs; offset++) {
480 code = get_vlc2(gb, vlc->table, VLCBITS, VLCMAX);
483 offset += run_table[code];
484 sign = get_bits1(gb) - 1;
485 iptr[offset & coef_mask] = ilvl[code] ^ sign<<31;
486 } else if (code == 1) {
492 level = get_bits(gb, coef_nb_bits);
493 /** NOTE: this is rather suboptimal. reading
494 block_len_bits would be better */
495 offset += get_bits(gb, frame_len_bits);
497 level = ff_wma_get_large_val(gb);
502 av_log(avctx,AV_LOG_ERROR,
503 "broken escape sequence\n");
506 offset += get_bits(gb, frame_len_bits) + 4;
508 offset += get_bits(gb, 2) + 1;
511 sign = get_bits1(gb) - 1;
512 ptr[offset & coef_mask] = (level^sign) - sign;
515 /** NOTE: EOB can be omitted */
516 if (offset > num_coefs) {
517 av_log(avctx, AV_LOG_ERROR, "overflow in spectral RLE, ignoring\n");