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"
27 #include "wma_common.h"
28 #include "wma_freqs.h"
34 /* XXX: use same run/length optimization as mpeg decoders */
35 // FIXME maybe split decode / encode or pass flag
36 static av_cold int init_coef_vlc(VLC *vlc, uint16_t **prun_table,
37 float **plevel_table, uint16_t **pint_table,
38 const CoefVLCTable *vlc_table)
41 const uint8_t *table_bits = vlc_table->huffbits;
42 const uint32_t *table_codes = vlc_table->huffcodes;
43 const uint16_t *levels_table = vlc_table->levels;
44 uint16_t *run_table, *level_table, *int_table;
46 int i, l, j, k, level;
48 init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0);
50 run_table = av_malloc(n * sizeof(uint16_t));
51 level_table = av_malloc(n * sizeof(uint16_t));
52 flevel_table = av_malloc(n * sizeof(*flevel_table));
53 int_table = av_malloc(n * sizeof(uint16_t));
54 if (!run_table || !level_table || !flevel_table || !int_table) {
56 av_freep(&level_table);
57 av_freep(&flevel_table);
59 return AVERROR(ENOMEM);
66 l = levels_table[k++];
67 for (j = 0; j < l; j++) {
69 level_table[i] = level;
70 flevel_table[i] = level;
75 *prun_table = run_table;
76 *plevel_table = flevel_table;
77 *pint_table = int_table;
83 av_cold int ff_wma_init(AVCodecContext *avctx, int flags2)
85 WMACodecContext *s = avctx->priv_data;
87 float bps1, high_freq;
92 if (avctx->sample_rate <= 0 || avctx->sample_rate > 50000 ||
93 avctx->channels <= 0 || avctx->channels > 2 ||
97 avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
99 if (avctx->codec->id == AV_CODEC_ID_WMAV1)
104 /* compute MDCT block size */
105 s->frame_len_bits = ff_wma_get_frame_len_bits(avctx->sample_rate,
107 s->next_block_len_bits = s->frame_len_bits;
108 s->prev_block_len_bits = s->frame_len_bits;
109 s->block_len_bits = s->frame_len_bits;
111 s->frame_len = 1 << s->frame_len_bits;
112 if (s->use_variable_block_len) {
114 nb = ((flags2 >> 3) & 3) + 1;
115 if ((avctx->bit_rate / avctx->channels) >= 32000)
117 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
120 s->nb_block_sizes = nb + 1;
122 s->nb_block_sizes = 1;
124 /* init rate dependent parameters */
125 s->use_noise_coding = 1;
126 high_freq = avctx->sample_rate * 0.5;
128 /* if version 2, then the rates are normalized */
129 sample_rate1 = avctx->sample_rate;
130 if (s->version == 2) {
131 if (sample_rate1 >= 44100)
132 sample_rate1 = 44100;
133 else if (sample_rate1 >= 22050)
134 sample_rate1 = 22050;
135 else if (sample_rate1 >= 16000)
136 sample_rate1 = 16000;
137 else if (sample_rate1 >= 11025)
138 sample_rate1 = 11025;
139 else if (sample_rate1 >= 8000)
143 bps = (float) avctx->bit_rate /
144 (float) (avctx->channels * avctx->sample_rate);
145 s->byte_offset_bits = av_log2((int) (bps * s->frame_len / 8.0 + 0.5)) + 2;
147 /* compute high frequency value and choose if noise coding should
150 if (avctx->channels == 2)
152 if (sample_rate1 == 44100) {
154 s->use_noise_coding = 0;
156 high_freq = high_freq * 0.4;
157 } else if (sample_rate1 == 22050) {
159 s->use_noise_coding = 0;
160 else if (bps1 >= 0.72)
161 high_freq = high_freq * 0.7;
163 high_freq = high_freq * 0.6;
164 } else if (sample_rate1 == 16000) {
166 high_freq = high_freq * 0.5;
168 high_freq = high_freq * 0.3;
169 } else if (sample_rate1 == 11025)
170 high_freq = high_freq * 0.7;
171 else if (sample_rate1 == 8000) {
173 high_freq = high_freq * 0.5;
175 s->use_noise_coding = 0;
177 high_freq = high_freq * 0.65;
180 high_freq = high_freq * 0.75;
182 high_freq = high_freq * 0.6;
184 high_freq = high_freq * 0.5;
186 av_dlog(s->avctx, "flags2=0x%x\n", flags2);
187 av_dlog(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
188 s->version, avctx->channels, avctx->sample_rate, avctx->bit_rate,
190 av_dlog(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
191 bps, bps1, high_freq, s->byte_offset_bits);
192 av_dlog(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
193 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
195 /* compute the scale factor band sizes for each MDCT block size */
197 int a, b, pos, lpos, k, block_len, i, j, n;
198 const uint8_t *table;
204 for (k = 0; k < s->nb_block_sizes; k++) {
205 block_len = s->frame_len >> k;
207 if (s->version == 1) {
209 for (i = 0; i < 25; i++) {
210 a = ff_wma_critical_freqs[i];
211 b = avctx->sample_rate;
212 pos = ((block_len * 2 * a) + (b >> 1)) / b;
215 s->exponent_bands[0][i] = pos - lpos;
216 if (pos >= block_len) {
222 s->exponent_sizes[0] = i;
224 /* hardcoded tables */
226 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
228 if (avctx->sample_rate >= 44100)
229 table = exponent_band_44100[a];
230 else if (avctx->sample_rate >= 32000)
231 table = exponent_band_32000[a];
232 else if (avctx->sample_rate >= 22050)
233 table = exponent_band_22050[a];
237 for (i = 0; i < n; i++)
238 s->exponent_bands[k][i] = table[i];
239 s->exponent_sizes[k] = n;
243 for (i = 0; i < 25; i++) {
244 a = ff_wma_critical_freqs[i];
245 b = avctx->sample_rate;
246 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
251 s->exponent_bands[k][j++] = pos - lpos;
252 if (pos >= block_len)
256 s->exponent_sizes[k] = j;
260 /* max number of coefs */
261 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
262 /* high freq computation */
263 s->high_band_start[k] = (int) ((block_len * 2 * high_freq) /
264 avctx->sample_rate + 0.5);
265 n = s->exponent_sizes[k];
268 for (i = 0; i < n; i++) {
271 pos += s->exponent_bands[k][i];
273 if (start < s->high_band_start[k])
274 start = s->high_band_start[k];
275 if (end > s->coefs_end[k])
276 end = s->coefs_end[k];
278 s->exponent_high_bands[k][j++] = end - start;
280 s->exponent_high_sizes[k] = j;
282 tprintf(s->avctx, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
285 s->high_band_start[k],
286 s->exponent_high_sizes[k]);
287 for (j = 0; j < s->exponent_high_sizes[k]; j++)
288 tprintf(s->avctx, " %d", s->exponent_high_bands[k][j]);
289 tprintf(s->avctx, "\n");
297 for (i = 0; i < s->nb_block_sizes; i++) {
298 tprintf(s->avctx, "%5d: n=%2d:",
300 s->exponent_sizes[i]);
301 for (j = 0; j < s->exponent_sizes[i]; j++)
302 tprintf(s->avctx, " %d", s->exponent_bands[i][j]);
303 tprintf(s->avctx, "\n");
308 /* init MDCT windows : simple sine window */
309 for (i = 0; i < s->nb_block_sizes; i++) {
310 ff_init_ff_sine_windows(s->frame_len_bits - i);
311 s->windows[i] = ff_sine_windows[s->frame_len_bits - i];
314 s->reset_block_lengths = 1;
316 if (s->use_noise_coding) {
317 /* init the noise generator */
319 s->noise_mult = 0.02;
321 s->noise_mult = 0.04;
324 for (i = 0; i < NOISE_TAB_SIZE; i++)
325 s->noise_table[i] = 1.0 * s->noise_mult;
331 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * s->noise_mult;
332 for (i = 0; i < NOISE_TAB_SIZE; i++) {
333 seed = seed * 314159 + 1;
334 s->noise_table[i] = (float) ((int) seed) * norm;
340 /* choose the VLC tables for the coefficients */
342 if (avctx->sample_rate >= 32000) {
345 else if (bps1 < 1.16)
348 s->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
349 s->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
350 ret = init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
351 &s->int_table[0], s->coef_vlcs[0]);
355 return init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
356 &s->int_table[1], s->coef_vlcs[1]);
359 int ff_wma_total_gain_to_bits(int total_gain)
363 else if (total_gain < 32)
365 else if (total_gain < 40)
367 else if (total_gain < 45)
373 int ff_wma_end(AVCodecContext *avctx)
375 WMACodecContext *s = avctx->priv_data;
378 for (i = 0; i < s->nb_block_sizes; i++)
379 ff_mdct_end(&s->mdct_ctx[i]);
382 ff_free_vlc(&s->exp_vlc);
383 if (s->use_noise_coding)
384 ff_free_vlc(&s->hgain_vlc);
385 for (i = 0; i < 2; i++) {
386 ff_free_vlc(&s->coef_vlc[i]);
387 av_free(s->run_table[i]);
388 av_free(s->level_table[i]);
389 av_free(s->int_table[i]);
396 * Decode an uncompressed coefficient.
397 * @param gb GetBitContext
398 * @return the decoded coefficient
400 unsigned int ff_wma_get_large_val(GetBitContext *gb)
402 /** consumes up to 34 bits */
413 return get_bits_long(gb, n_bits);
417 * Decode run level compressed coefficients.
418 * @param avctx codec context
419 * @param gb bitstream reader context
420 * @param vlc vlc table for get_vlc2
421 * @param level_table level codes
422 * @param run_table run codes
423 * @param version 0 for wma1,2 1 for wmapro
424 * @param ptr output buffer
425 * @param offset offset in the output buffer
426 * @param num_coefs number of input coefficents
427 * @param block_len input buffer length (2^n)
428 * @param frame_len_bits number of bits for escaped run codes
429 * @param coef_nb_bits number of bits for escaped level codes
430 * @return 0 on success, -1 otherwise
432 int ff_wma_run_level_decode(AVCodecContext *avctx, GetBitContext *gb,
433 VLC *vlc, const float *level_table,
434 const uint16_t *run_table, int version,
435 WMACoef *ptr, int offset, int num_coefs,
436 int block_len, int frame_len_bits,
439 int code, level, sign;
440 const uint32_t *ilvl = (const uint32_t *) level_table;
441 uint32_t *iptr = (uint32_t *) ptr;
442 const unsigned int coef_mask = block_len - 1;
443 for (; offset < num_coefs; offset++) {
444 code = get_vlc2(gb, vlc->table, VLCBITS, VLCMAX);
447 offset += run_table[code];
448 sign = get_bits1(gb) - 1;
449 iptr[offset & coef_mask] = ilvl[code] ^ sign << 31;
450 } else if (code == 1) {
456 level = get_bits(gb, coef_nb_bits);
457 /** NOTE: this is rather suboptimal. reading
458 * block_len_bits would be better */
459 offset += get_bits(gb, frame_len_bits);
461 level = ff_wma_get_large_val(gb);
466 av_log(avctx, AV_LOG_ERROR,
467 "broken escape sequence\n");
470 offset += get_bits(gb, frame_len_bits) + 4;
472 offset += get_bits(gb, 2) + 1;
475 sign = get_bits1(gb) - 1;
476 ptr[offset & coef_mask] = (level ^ sign) - sign;
479 /** NOTE: EOB can be omitted */
480 if (offset > num_coefs) {
481 av_log(avctx, AV_LOG_ERROR, "overflow in spectral RLE, ignoring\n");