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
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 || version < 3) {
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);
140 s->next_block_len_bits = s->frame_len_bits;
141 s->prev_block_len_bits = s->frame_len_bits;
142 s->block_len_bits = s->frame_len_bits;
144 s->frame_len = 1 << s->frame_len_bits;
145 if (s->use_variable_block_len) {
147 nb = ((flags2 >> 3) & 3) + 1;
148 if ((s->bit_rate / s->nb_channels) >= 32000)
150 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
153 s->nb_block_sizes = nb + 1;
155 s->nb_block_sizes = 1;
158 /* init rate dependent parameters */
159 s->use_noise_coding = 1;
160 high_freq = s->sample_rate * 0.5;
162 /* if version 2, then the rates are normalized */
163 sample_rate1 = s->sample_rate;
164 if (s->version == 2) {
165 if (sample_rate1 >= 44100) {
166 sample_rate1 = 44100;
167 } else if (sample_rate1 >= 22050) {
168 sample_rate1 = 22050;
169 } else if (sample_rate1 >= 16000) {
170 sample_rate1 = 16000;
171 } else if (sample_rate1 >= 11025) {
172 sample_rate1 = 11025;
173 } else if (sample_rate1 >= 8000) {
178 bps = (float)s->bit_rate / (float)(s->nb_channels * s->sample_rate);
179 s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0 + 0.5)) + 2;
181 /* compute high frequency value and choose if noise coding should
184 if (s->nb_channels == 2)
186 if (sample_rate1 == 44100) {
188 s->use_noise_coding = 0;
190 high_freq = high_freq * 0.4;
192 } else if (sample_rate1 == 22050) {
194 s->use_noise_coding = 0;
195 } else if (bps1 >= 0.72) {
196 high_freq = high_freq * 0.7;
198 high_freq = high_freq * 0.6;
200 } else if (sample_rate1 == 16000) {
202 high_freq = high_freq * 0.5;
204 high_freq = high_freq * 0.3;
206 } else if (sample_rate1 == 11025) {
207 high_freq = high_freq * 0.7;
208 } else if (sample_rate1 == 8000) {
210 high_freq = high_freq * 0.5;
211 } else if (bps > 0.75) {
212 s->use_noise_coding = 0;
214 high_freq = high_freq * 0.65;
218 high_freq = high_freq * 0.75;
219 } else if (bps >= 0.6) {
220 high_freq = high_freq * 0.6;
222 high_freq = high_freq * 0.5;
225 av_dlog(s->avctx, "flags2=0x%x\n", flags2);
226 av_dlog(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
227 s->version, s->nb_channels, s->sample_rate, s->bit_rate,
229 av_dlog(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
230 bps, bps1, high_freq, s->byte_offset_bits);
231 av_dlog(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
232 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
234 /* compute the scale factor band sizes for each MDCT block size */
236 int a, b, pos, lpos, k, block_len, i, j, n;
237 const uint8_t *table;
239 if (s->version == 1) {
244 for (k = 0; k < s->nb_block_sizes; k++) {
245 block_len = s->frame_len >> k;
247 if (s->version == 1) {
249 for (i = 0; i < 25; i++) {
250 a = ff_wma_critical_freqs[i];
252 pos = ((block_len * 2 * a) + (b >> 1)) / b;
255 s->exponent_bands[0][i] = pos - lpos;
256 if (pos >= block_len) {
262 s->exponent_sizes[0] = i;
264 /* hardcoded tables */
266 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
268 if (s->sample_rate >= 44100) {
269 table = exponent_band_44100[a];
270 } else if (s->sample_rate >= 32000) {
271 table = exponent_band_32000[a];
272 } else if (s->sample_rate >= 22050) {
273 table = exponent_band_22050[a];
278 for (i = 0; i < n; i++)
279 s->exponent_bands[k][i] = table[i];
280 s->exponent_sizes[k] = n;
284 for (i = 0; i < 25; i++) {
285 a = ff_wma_critical_freqs[i];
287 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
292 s->exponent_bands[k][j++] = pos - lpos;
293 if (pos >= block_len)
297 s->exponent_sizes[k] = j;
301 /* max number of coefs */
302 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
303 /* high freq computation */
304 s->high_band_start[k] = (int)((block_len * 2 * high_freq) /
305 s->sample_rate + 0.5);
306 n = s->exponent_sizes[k];
309 for (i = 0; i < n; i++) {
312 pos += s->exponent_bands[k][i];
314 if (start < s->high_band_start[k])
315 start = s->high_band_start[k];
316 if (end > s->coefs_end[k])
317 end = s->coefs_end[k];
319 s->exponent_high_bands[k][j++] = end - start;
321 s->exponent_high_sizes[k] = j;
323 tprintf(s->avctx, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
326 s->high_band_start[k],
327 s->exponent_high_sizes[k]);
328 for (j = 0; j < s->exponent_high_sizes[k]; j++)
329 tprintf(s->avctx, " %d", s->exponent_high_bands[k][j]);
330 tprintf(s->avctx, "\n");
338 for (i = 0; i < s->nb_block_sizes; i++) {
339 tprintf(s->avctx, "%5d: n=%2d:",
341 s->exponent_sizes[i]);
342 for (j = 0; j < s->exponent_sizes[i]; j++)
343 tprintf(s->avctx, " %d", s->exponent_bands[i][j]);
344 tprintf(s->avctx, "\n");
349 /* init MDCT windows : simple sinus window */
350 for (i = 0; i < s->nb_block_sizes; i++) {
351 ff_init_ff_sine_windows(s->frame_len_bits - i);
352 s->windows[i] = ff_sine_windows[s->frame_len_bits - i];
355 s->reset_block_lengths = 1;
357 if (s->use_noise_coding) {
359 /* init the noise generator */
360 if (s->use_exp_vlc) {
361 s->noise_mult = 0.02;
363 s->noise_mult = 0.04;
367 for (i = 0; i < NOISE_TAB_SIZE; i++)
368 s->noise_table[i] = 1.0 * s->noise_mult;
374 norm = (1.0 / (float)(1LL << 31)) * sqrt(3) * s->noise_mult;
375 for (i = 0; i < NOISE_TAB_SIZE; i++) {
376 seed = seed * 314159 + 1;
377 s->noise_table[i] = (float)((int)seed) * norm;
383 /* choose the VLC tables for the coefficients */
385 if (s->sample_rate >= 32000) {
388 } else if (bps1 < 1.16) {
392 s->coef_vlcs[0]= &coef_vlcs[coef_vlc_table * 2 ];
393 s->coef_vlcs[1]= &coef_vlcs[coef_vlc_table * 2 + 1];
394 init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0], &s->int_table[0],
396 init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1], &s->int_table[1],
402 int ff_wma_total_gain_to_bits(int total_gain)
404 if (total_gain < 15) return 13;
405 else if (total_gain < 32) return 12;
406 else if (total_gain < 40) return 11;
407 else if (total_gain < 45) return 10;
411 int ff_wma_end(AVCodecContext *avctx)
413 WMACodecContext *s = avctx->priv_data;
416 for (i = 0; i < s->nb_block_sizes; i++)
417 ff_mdct_end(&s->mdct_ctx[i]);
419 if (s->use_exp_vlc) {
420 free_vlc(&s->exp_vlc);
422 if (s->use_noise_coding) {
423 free_vlc(&s->hgain_vlc);
425 for (i = 0; i < 2; i++) {
426 free_vlc(&s->coef_vlc[i]);
427 av_free(s->run_table[i]);
428 av_free(s->level_table[i]);
429 av_free(s->int_table[i]);
436 * Decode an uncompressed coefficient.
437 * @param gb GetBitContext
438 * @return the decoded coefficient
440 unsigned int ff_wma_get_large_val(GetBitContext* gb)
442 /** consumes up to 34 bits */
454 return get_bits_long(gb, n_bits);
458 * Decode run level compressed coefficients.
459 * @param avctx codec context
460 * @param gb bitstream reader context
461 * @param vlc vlc table for get_vlc2
462 * @param level_table level codes
463 * @param run_table run codes
464 * @param version 0 for wma1,2 1 for wmapro
465 * @param ptr output buffer
466 * @param offset offset in the output buffer
467 * @param num_coefs number of input coefficents
468 * @param block_len input buffer length (2^n)
469 * @param frame_len_bits number of bits for escaped run codes
470 * @param coef_nb_bits number of bits for escaped level codes
471 * @return 0 on success, -1 otherwise
473 int ff_wma_run_level_decode(AVCodecContext* avctx, GetBitContext* gb,
475 const float *level_table, const uint16_t *run_table,
476 int version, WMACoef *ptr, int offset,
477 int num_coefs, int block_len, int frame_len_bits,
480 int code, level, sign;
481 const uint32_t *ilvl = (const uint32_t*)level_table;
482 uint32_t *iptr = (uint32_t*)ptr;
483 const unsigned int coef_mask = block_len - 1;
484 for (; offset < num_coefs; offset++) {
485 code = get_vlc2(gb, vlc->table, VLCBITS, VLCMAX);
488 offset += run_table[code];
489 sign = get_bits1(gb) - 1;
490 iptr[offset & coef_mask] = ilvl[code] ^ sign<<31;
491 } else if (code == 1) {
497 level = get_bits(gb, coef_nb_bits);
498 /** NOTE: this is rather suboptimal. reading
499 block_len_bits would be better */
500 offset += get_bits(gb, frame_len_bits);
502 level = ff_wma_get_large_val(gb);
507 av_log(avctx,AV_LOG_ERROR,
508 "broken escape sequence\n");
511 offset += get_bits(gb, frame_len_bits) + 4;
513 offset += get_bits(gb, 2) + 1;
516 sign = get_bits1(gb) - 1;
517 ptr[offset & coef_mask] = (level^sign) - sign;
520 /** NOTE: EOB can be omitted */
521 if (offset > num_coefs) {
522 av_log(avctx, AV_LOG_ERROR, "overflow in spectral RLE, ignoring\n");