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
25 #include "wma_common.h"
31 /* XXX: use same run/length optimization as mpeg decoders */
32 //FIXME maybe split decode / encode or pass flag
33 static void init_coef_vlc(VLC *vlc, uint16_t **prun_table,
34 float **plevel_table, uint16_t **pint_table,
35 const CoefVLCTable *vlc_table)
38 const uint8_t *table_bits = vlc_table->huffbits;
39 const uint32_t *table_codes = vlc_table->huffcodes;
40 const uint16_t *levels_table = vlc_table->levels;
41 uint16_t *run_table, *level_table, *int_table;
43 int i, l, j, k, level;
45 init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0);
47 run_table = av_malloc(n * sizeof(uint16_t));
48 level_table = av_malloc(n * sizeof(uint16_t));
49 flevel_table= av_malloc(n * sizeof(*flevel_table));
50 int_table = av_malloc(n * sizeof(uint16_t));
56 l = levels_table[k++];
57 for (j = 0; j < l; j++) {
59 level_table[i] = level;
60 flevel_table[i]= level;
65 *prun_table = run_table;
66 *plevel_table = flevel_table;
67 *pint_table = int_table;
71 int ff_wma_init(AVCodecContext *avctx, int flags2)
73 WMACodecContext *s = avctx->priv_data;
75 float bps1, high_freq;
80 if ( avctx->sample_rate <= 0 || avctx->sample_rate > 50000
81 || avctx->channels <= 0 || avctx->channels > 2
82 || avctx->bit_rate <= 0)
85 ff_fmt_convert_init(&s->fmt_conv, avctx);
86 avpriv_float_dsp_init(&s->fdsp, avctx->flags & CODEC_FLAG_BITEXACT);
88 if (avctx->codec->id == AV_CODEC_ID_WMAV1) {
94 /* compute MDCT block size */
95 s->frame_len_bits = ff_wma_get_frame_len_bits(avctx->sample_rate,
97 s->next_block_len_bits = s->frame_len_bits;
98 s->prev_block_len_bits = s->frame_len_bits;
99 s->block_len_bits = s->frame_len_bits;
101 s->frame_len = 1 << s->frame_len_bits;
102 if (s->use_variable_block_len) {
104 nb = ((flags2 >> 3) & 3) + 1;
105 if ((avctx->bit_rate / avctx->channels) >= 32000)
107 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
110 s->nb_block_sizes = nb + 1;
112 s->nb_block_sizes = 1;
115 /* init rate dependent parameters */
116 s->use_noise_coding = 1;
117 high_freq = avctx->sample_rate * 0.5;
119 /* if version 2, then the rates are normalized */
120 sample_rate1 = avctx->sample_rate;
121 if (s->version == 2) {
122 if (sample_rate1 >= 44100) {
123 sample_rate1 = 44100;
124 } else if (sample_rate1 >= 22050) {
125 sample_rate1 = 22050;
126 } else if (sample_rate1 >= 16000) {
127 sample_rate1 = 16000;
128 } else if (sample_rate1 >= 11025) {
129 sample_rate1 = 11025;
130 } else if (sample_rate1 >= 8000) {
135 bps = (float)avctx->bit_rate / (float)(avctx->channels * avctx->sample_rate);
136 s->byte_offset_bits = av_log2((int)(bps * s->frame_len / 8.0 + 0.5)) + 2;
138 /* compute high frequency value and choose if noise coding should
141 if (avctx->channels == 2)
143 if (sample_rate1 == 44100) {
145 s->use_noise_coding = 0;
147 high_freq = high_freq * 0.4;
149 } else if (sample_rate1 == 22050) {
151 s->use_noise_coding = 0;
152 } else if (bps1 >= 0.72) {
153 high_freq = high_freq * 0.7;
155 high_freq = high_freq * 0.6;
157 } else if (sample_rate1 == 16000) {
159 high_freq = high_freq * 0.5;
161 high_freq = high_freq * 0.3;
163 } else if (sample_rate1 == 11025) {
164 high_freq = high_freq * 0.7;
165 } else if (sample_rate1 == 8000) {
167 high_freq = high_freq * 0.5;
168 } else if (bps > 0.75) {
169 s->use_noise_coding = 0;
171 high_freq = high_freq * 0.65;
175 high_freq = high_freq * 0.75;
176 } else if (bps >= 0.6) {
177 high_freq = high_freq * 0.6;
179 high_freq = high_freq * 0.5;
182 av_dlog(s->avctx, "flags2=0x%x\n", flags2);
183 av_dlog(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
184 s->version, avctx->channels, avctx->sample_rate, avctx->bit_rate,
186 av_dlog(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
187 bps, bps1, high_freq, s->byte_offset_bits);
188 av_dlog(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
189 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
191 /* compute the scale factor band sizes for each MDCT block size */
193 int a, b, pos, lpos, k, block_len, i, j, n;
194 const uint8_t *table;
196 if (s->version == 1) {
201 for (k = 0; k < s->nb_block_sizes; k++) {
202 block_len = s->frame_len >> k;
204 if (s->version == 1) {
206 for (i = 0; i < 25; i++) {
207 a = ff_wma_critical_freqs[i];
208 b = avctx->sample_rate;
209 pos = ((block_len * 2 * a) + (b >> 1)) / b;
212 s->exponent_bands[0][i] = pos - lpos;
213 if (pos >= block_len) {
219 s->exponent_sizes[0] = i;
221 /* hardcoded tables */
223 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
225 if (avctx->sample_rate >= 44100) {
226 table = exponent_band_44100[a];
227 } else if (avctx->sample_rate >= 32000) {
228 table = exponent_band_32000[a];
229 } else if (avctx->sample_rate >= 22050) {
230 table = exponent_band_22050[a];
235 for (i = 0; i < n; i++)
236 s->exponent_bands[k][i] = table[i];
237 s->exponent_sizes[k] = n;
241 for (i = 0; i < 25; i++) {
242 a = ff_wma_critical_freqs[i];
243 b = avctx->sample_rate;
244 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
249 s->exponent_bands[k][j++] = pos - lpos;
250 if (pos >= block_len)
254 s->exponent_sizes[k] = j;
258 /* max number of coefs */
259 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
260 /* high freq computation */
261 s->high_band_start[k] = (int)((block_len * 2 * high_freq) /
262 avctx->sample_rate + 0.5);
263 n = s->exponent_sizes[k];
266 for (i = 0; i < n; i++) {
269 pos += s->exponent_bands[k][i];
271 if (start < s->high_band_start[k])
272 start = s->high_band_start[k];
273 if (end > s->coefs_end[k])
274 end = s->coefs_end[k];
276 s->exponent_high_bands[k][j++] = end - start;
278 s->exponent_high_sizes[k] = j;
280 tprintf(s->avctx, "%5d: coefs_end=%d high_band_start=%d nb_high_bands=%d: ",
283 s->high_band_start[k],
284 s->exponent_high_sizes[k]);
285 for (j = 0; j < s->exponent_high_sizes[k]; j++)
286 tprintf(s->avctx, " %d", s->exponent_high_bands[k][j]);
287 tprintf(s->avctx, "\n");
295 for (i = 0; i < s->nb_block_sizes; i++) {
296 tprintf(s->avctx, "%5d: n=%2d:",
298 s->exponent_sizes[i]);
299 for (j = 0; j < s->exponent_sizes[i]; j++)
300 tprintf(s->avctx, " %d", s->exponent_bands[i][j]);
301 tprintf(s->avctx, "\n");
306 /* init MDCT windows : simple sinus window */
307 for (i = 0; i < s->nb_block_sizes; i++) {
308 ff_init_ff_sine_windows(s->frame_len_bits - i);
309 s->windows[i] = ff_sine_windows[s->frame_len_bits - i];
312 s->reset_block_lengths = 1;
314 if (s->use_noise_coding) {
316 /* init the noise generator */
317 if (s->use_exp_vlc) {
318 s->noise_mult = 0.02;
320 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) {
349 s->coef_vlcs[0]= &coef_vlcs[coef_vlc_table * 2 ];
350 s->coef_vlcs[1]= &coef_vlcs[coef_vlc_table * 2 + 1];
351 init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0], &s->int_table[0],
353 init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1], &s->int_table[1],
359 int ff_wma_total_gain_to_bits(int total_gain)
361 if (total_gain < 15) return 13;
362 else if (total_gain < 32) return 12;
363 else if (total_gain < 40) return 11;
364 else if (total_gain < 45) return 10;
368 int ff_wma_end(AVCodecContext *avctx)
370 WMACodecContext *s = avctx->priv_data;
373 for (i = 0; i < s->nb_block_sizes; i++)
374 ff_mdct_end(&s->mdct_ctx[i]);
376 if (s->use_exp_vlc) {
377 ff_free_vlc(&s->exp_vlc);
379 if (s->use_noise_coding) {
380 ff_free_vlc(&s->hgain_vlc);
382 for (i = 0; i < 2; i++) {
383 ff_free_vlc(&s->coef_vlc[i]);
384 av_free(s->run_table[i]);
385 av_free(s->level_table[i]);
386 av_free(s->int_table[i]);
393 * Decode an uncompressed coefficient.
394 * @param gb GetBitContext
395 * @return the decoded coefficient
397 unsigned int ff_wma_get_large_val(GetBitContext* gb)
399 /** consumes up to 34 bits */
411 return get_bits_long(gb, n_bits);
415 * Decode run level compressed coefficients.
416 * @param avctx codec context
417 * @param gb bitstream reader context
418 * @param vlc vlc table for get_vlc2
419 * @param level_table level codes
420 * @param run_table run codes
421 * @param version 0 for wma1,2 1 for wmapro
422 * @param ptr output buffer
423 * @param offset offset in the output buffer
424 * @param num_coefs number of input coefficents
425 * @param block_len input buffer length (2^n)
426 * @param frame_len_bits number of bits for escaped run codes
427 * @param coef_nb_bits number of bits for escaped level codes
428 * @return 0 on success, -1 otherwise
430 int ff_wma_run_level_decode(AVCodecContext* avctx, GetBitContext* gb,
432 const float *level_table, const uint16_t *run_table,
433 int version, WMACoef *ptr, int offset,
434 int num_coefs, int block_len, int frame_len_bits,
437 int code, level, sign;
438 const uint32_t *ilvl = (const uint32_t*)level_table;
439 uint32_t *iptr = (uint32_t*)ptr;
440 const unsigned int coef_mask = block_len - 1;
441 for (; offset < num_coefs; offset++) {
442 code = get_vlc2(gb, vlc->table, VLCBITS, VLCMAX);
445 offset += run_table[code];
446 sign = get_bits1(gb) - 1;
447 iptr[offset & coef_mask] = ilvl[code] ^ sign<<31;
448 } else if (code == 1) {
454 level = get_bits(gb, coef_nb_bits);
455 /** NOTE: this is rather suboptimal. reading
456 block_len_bits would be better */
457 offset += get_bits(gb, frame_len_bits);
459 level = ff_wma_get_large_val(gb);
464 av_log(avctx,AV_LOG_ERROR,
465 "broken escape sequence\n");
468 offset += get_bits(gb, frame_len_bits) + 4;
470 offset += get_bits(gb, 2) + 1;
473 sign = get_bits1(gb) - 1;
474 ptr[offset & coef_mask] = (level^sign) - sign;
477 /** NOTE: EOB can be omitted */
478 if (offset > num_coefs) {
479 av_log(avctx, AV_LOG_ERROR, "overflow in spectral RLE, ignoring\n");