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
22 #include "libavutil/attributes.h"
28 #include "wma_common.h"
29 #include "wma_freqs.h"
35 /* XXX: use same run/length optimization as mpeg decoders */
36 // FIXME maybe split decode / encode or pass flag
37 static av_cold int init_coef_vlc(VLC *vlc, uint16_t **prun_table,
38 float **plevel_table, uint16_t **pint_table,
39 const CoefVLCTable *vlc_table)
42 const uint8_t *table_bits = vlc_table->huffbits;
43 const uint32_t *table_codes = vlc_table->huffcodes;
44 const uint16_t *levels_table = vlc_table->levels;
45 uint16_t *run_table, *level_table, *int_table;
47 int i, l, j, k, level;
49 init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0);
51 run_table = av_malloc(n * sizeof(uint16_t));
52 level_table = av_malloc(n * sizeof(uint16_t));
53 flevel_table = av_malloc(n * sizeof(*flevel_table));
54 int_table = av_malloc(n * sizeof(uint16_t));
55 if (!run_table || !level_table || !flevel_table || !int_table) {
57 av_freep(&level_table);
58 av_freep(&flevel_table);
60 return AVERROR(ENOMEM);
67 l = levels_table[k++];
68 for (j = 0; j < l; j++) {
70 level_table[i] = level;
71 flevel_table[i] = level;
76 *prun_table = run_table;
77 *plevel_table = flevel_table;
78 *pint_table = int_table;
84 av_cold int ff_wma_init(AVCodecContext *avctx, int flags2)
86 WMACodecContext *s = avctx->priv_data;
88 float bps1, high_freq;
93 if (avctx->sample_rate <= 0 || avctx->sample_rate > 50000 ||
94 avctx->channels <= 0 || avctx->channels > 2 ||
98 avpriv_float_dsp_init(&s->fdsp, avctx->flags & AV_CODEC_FLAG_BITEXACT);
100 if (avctx->codec->id == AV_CODEC_ID_WMAV1)
105 /* compute MDCT block size */
106 s->frame_len_bits = ff_wma_get_frame_len_bits(avctx->sample_rate,
108 s->next_block_len_bits = s->frame_len_bits;
109 s->prev_block_len_bits = s->frame_len_bits;
110 s->block_len_bits = s->frame_len_bits;
112 s->frame_len = 1 << s->frame_len_bits;
113 if (s->use_variable_block_len) {
115 nb = ((flags2 >> 3) & 3) + 1;
116 if ((avctx->bit_rate / avctx->channels) >= 32000)
118 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
121 s->nb_block_sizes = nb + 1;
123 s->nb_block_sizes = 1;
125 /* init rate dependent parameters */
126 s->use_noise_coding = 1;
127 high_freq = avctx->sample_rate * 0.5;
129 /* if version 2, then the rates are normalized */
130 sample_rate1 = avctx->sample_rate;
131 if (s->version == 2) {
132 if (sample_rate1 >= 44100)
133 sample_rate1 = 44100;
134 else if (sample_rate1 >= 22050)
135 sample_rate1 = 22050;
136 else if (sample_rate1 >= 16000)
137 sample_rate1 = 16000;
138 else if (sample_rate1 >= 11025)
139 sample_rate1 = 11025;
140 else if (sample_rate1 >= 8000)
144 bps = (float) avctx->bit_rate /
145 (float) (avctx->channels * avctx->sample_rate);
146 s->byte_offset_bits = av_log2((int) (bps * s->frame_len / 8.0 + 0.5)) + 2;
148 /* compute high frequency value and choose if noise coding should
151 if (avctx->channels == 2)
153 if (sample_rate1 == 44100) {
155 s->use_noise_coding = 0;
157 high_freq = high_freq * 0.4;
158 } else if (sample_rate1 == 22050) {
160 s->use_noise_coding = 0;
161 else if (bps1 >= 0.72)
162 high_freq = high_freq * 0.7;
164 high_freq = high_freq * 0.6;
165 } else if (sample_rate1 == 16000) {
167 high_freq = high_freq * 0.5;
169 high_freq = high_freq * 0.3;
170 } else if (sample_rate1 == 11025)
171 high_freq = high_freq * 0.7;
172 else if (sample_rate1 == 8000) {
174 high_freq = high_freq * 0.5;
176 s->use_noise_coding = 0;
178 high_freq = high_freq * 0.65;
181 high_freq = high_freq * 0.75;
183 high_freq = high_freq * 0.6;
185 high_freq = high_freq * 0.5;
187 ff_dlog(s->avctx, "flags2=0x%x\n", flags2);
188 ff_dlog(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
189 s->version, avctx->channels, avctx->sample_rate, avctx->bit_rate,
191 ff_dlog(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
192 bps, bps1, high_freq, s->byte_offset_bits);
193 ff_dlog(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
194 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
196 /* compute the scale factor band sizes for each MDCT block size */
198 int a, b, pos, lpos, k, block_len, i, j, n;
199 const uint8_t *table;
205 for (k = 0; k < s->nb_block_sizes; k++) {
206 block_len = s->frame_len >> k;
208 if (s->version == 1) {
210 for (i = 0; i < 25; i++) {
211 a = ff_wma_critical_freqs[i];
212 b = avctx->sample_rate;
213 pos = ((block_len * 2 * a) + (b >> 1)) / b;
216 s->exponent_bands[0][i] = pos - lpos;
217 if (pos >= block_len) {
223 s->exponent_sizes[0] = i;
225 /* hardcoded tables */
227 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
229 if (avctx->sample_rate >= 44100)
230 table = exponent_band_44100[a];
231 else if (avctx->sample_rate >= 32000)
232 table = exponent_band_32000[a];
233 else if (avctx->sample_rate >= 22050)
234 table = exponent_band_22050[a];
238 for (i = 0; i < n; i++)
239 s->exponent_bands[k][i] = table[i];
240 s->exponent_sizes[k] = n;
244 for (i = 0; i < 25; i++) {
245 a = ff_wma_critical_freqs[i];
246 b = avctx->sample_rate;
247 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
252 s->exponent_bands[k][j++] = pos - lpos;
253 if (pos >= block_len)
257 s->exponent_sizes[k] = j;
261 /* max number of coefs */
262 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
263 /* high freq computation */
264 s->high_band_start[k] = (int) ((block_len * 2 * high_freq) /
265 avctx->sample_rate + 0.5);
266 n = s->exponent_sizes[k];
269 for (i = 0; i < n; i++) {
272 pos += s->exponent_bands[k][i];
274 if (start < s->high_band_start[k])
275 start = s->high_band_start[k];
276 if (end > s->coefs_end[k])
277 end = s->coefs_end[k];
279 s->exponent_high_bands[k][j++] = end - start;
281 s->exponent_high_sizes[k] = j;
283 ff_tlog(s->avctx, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
286 s->high_band_start[k],
287 s->exponent_high_sizes[k]);
288 for (j = 0; j < s->exponent_high_sizes[k]; j++)
289 ff_tlog(s->avctx, " %d", s->exponent_high_bands[k][j]);
290 ff_tlog(s->avctx, "\n");
298 for (i = 0; i < s->nb_block_sizes; i++) {
299 ff_tlog(s->avctx, "%5d: n=%2d:",
301 s->exponent_sizes[i]);
302 for (j = 0; j < s->exponent_sizes[i]; j++)
303 ff_tlog(s->avctx, " %d", s->exponent_bands[i][j]);
304 ff_tlog(s->avctx, "\n");
309 /* init MDCT windows : simple sine window */
310 for (i = 0; i < s->nb_block_sizes; i++) {
311 ff_init_ff_sine_windows(s->frame_len_bits - i);
312 s->windows[i] = ff_sine_windows[s->frame_len_bits - i];
315 s->reset_block_lengths = 1;
317 if (s->use_noise_coding) {
318 /* init the noise generator */
320 s->noise_mult = 0.02;
322 s->noise_mult = 0.04;
325 for (i = 0; i < NOISE_TAB_SIZE; i++)
326 s->noise_table[i] = 1.0 * s->noise_mult;
332 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * s->noise_mult;
333 for (i = 0; i < NOISE_TAB_SIZE; i++) {
334 seed = seed * 314159 + 1;
335 s->noise_table[i] = (float) ((int) seed) * norm;
341 /* choose the VLC tables for the coefficients */
343 if (avctx->sample_rate >= 32000) {
346 else if (bps1 < 1.16)
349 s->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
350 s->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
351 ret = init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
352 &s->int_table[0], s->coef_vlcs[0]);
356 return init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
357 &s->int_table[1], s->coef_vlcs[1]);
360 int ff_wma_total_gain_to_bits(int total_gain)
364 else if (total_gain < 32)
366 else if (total_gain < 40)
368 else if (total_gain < 45)
374 int ff_wma_end(AVCodecContext *avctx)
376 WMACodecContext *s = avctx->priv_data;
379 for (i = 0; i < s->nb_block_sizes; i++)
380 ff_mdct_end(&s->mdct_ctx[i]);
383 ff_free_vlc(&s->exp_vlc);
384 if (s->use_noise_coding)
385 ff_free_vlc(&s->hgain_vlc);
386 for (i = 0; i < 2; i++) {
387 ff_free_vlc(&s->coef_vlc[i]);
388 av_free(s->run_table[i]);
389 av_free(s->level_table[i]);
390 av_free(s->int_table[i]);
397 * Decode an uncompressed coefficient.
398 * @param gb GetBitContext
399 * @return the decoded coefficient
401 unsigned int ff_wma_get_large_val(GetBitContext *gb)
403 /** consumes up to 34 bits */
414 return get_bits_long(gb, n_bits);
418 * Decode run level compressed coefficients.
419 * @param avctx codec context
420 * @param gb bitstream reader context
421 * @param vlc vlc table for get_vlc2
422 * @param level_table level codes
423 * @param run_table run codes
424 * @param version 0 for wma1,2 1 for wmapro
425 * @param ptr output buffer
426 * @param offset offset in the output buffer
427 * @param num_coefs number of input coefficents
428 * @param block_len input buffer length (2^n)
429 * @param frame_len_bits number of bits for escaped run codes
430 * @param coef_nb_bits number of bits for escaped level codes
431 * @return 0 on success, -1 otherwise
433 int ff_wma_run_level_decode(AVCodecContext *avctx, GetBitContext *gb,
434 VLC *vlc, const float *level_table,
435 const uint16_t *run_table, int version,
436 WMACoef *ptr, int offset, int num_coefs,
437 int block_len, int frame_len_bits,
440 int code, level, sign;
441 const uint32_t *ilvl = (const uint32_t *) level_table;
442 uint32_t *iptr = (uint32_t *) ptr;
443 const unsigned int coef_mask = block_len - 1;
444 for (; offset < num_coefs; offset++) {
445 code = get_vlc2(gb, vlc->table, VLCBITS, VLCMAX);
448 offset += run_table[code];
449 sign = get_bits1(gb) - 1;
450 iptr[offset & coef_mask] = ilvl[code] ^ sign << 31;
451 } else if (code == 1) {
457 level = get_bits(gb, coef_nb_bits);
458 /** NOTE: this is rather suboptimal. reading
459 * block_len_bits would be better */
460 offset += get_bits(gb, frame_len_bits);
462 level = ff_wma_get_large_val(gb);
467 av_log(avctx, AV_LOG_ERROR,
468 "broken escape sequence\n");
471 offset += get_bits(gb, frame_len_bits) + 4;
473 offset += get_bits(gb, 2) + 1;
476 sign = get_bits1(gb) - 1;
477 ptr[offset & coef_mask] = (level ^ sign) - sign;
480 /** NOTE: EOB can be omitted */
481 if (offset > num_coefs) {
482 av_log(avctx, AV_LOG_ERROR, "overflow in spectral RLE, ignoring\n");