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"
25 #include "bitstream.h"
29 #include "wma_common.h"
30 #include "wma_freqs.h"
33 /* XXX: use same run/length optimization as mpeg decoders */
34 // FIXME maybe split decode / encode or pass flag
35 static av_cold int init_coef_vlc(VLC *vlc, uint16_t **prun_table,
36 float **plevel_table, uint16_t **pint_table,
37 const CoefVLCTable *vlc_table)
40 const uint8_t *table_bits = vlc_table->huffbits;
41 const uint32_t *table_codes = vlc_table->huffcodes;
42 const uint16_t *levels_table = vlc_table->levels;
43 uint16_t *run_table, *level_table, *int_table;
45 int i, l, j, k, level;
47 init_vlc(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0);
49 run_table = av_malloc(n * sizeof(uint16_t));
50 level_table = av_malloc(n * sizeof(uint16_t));
51 flevel_table = av_malloc(n * sizeof(*flevel_table));
52 int_table = av_malloc(n * sizeof(uint16_t));
53 if (!run_table || !level_table || !flevel_table || !int_table) {
55 av_freep(&level_table);
56 av_freep(&flevel_table);
58 return AVERROR(ENOMEM);
65 l = levels_table[k++];
66 for (j = 0; j < l; j++) {
68 level_table[i] = level;
69 flevel_table[i] = level;
74 *prun_table = run_table;
75 *plevel_table = flevel_table;
76 *pint_table = int_table;
82 av_cold int ff_wma_init(AVCodecContext *avctx, int flags2)
84 WMACodecContext *s = avctx->priv_data;
86 float bps1, high_freq;
91 if (avctx->sample_rate <= 0 || avctx->sample_rate > 50000 ||
92 avctx->channels <= 0 || avctx->channels > 2 ||
96 avpriv_float_dsp_init(&s->fdsp, avctx->flags & AV_CODEC_FLAG_BITEXACT);
98 if (avctx->codec->id == AV_CODEC_ID_WMAV1)
103 /* compute MDCT block size */
104 s->frame_len_bits = ff_wma_get_frame_len_bits(avctx->sample_rate,
106 s->next_block_len_bits = s->frame_len_bits;
107 s->prev_block_len_bits = s->frame_len_bits;
108 s->block_len_bits = s->frame_len_bits;
110 s->frame_len = 1 << s->frame_len_bits;
111 if (s->use_variable_block_len) {
113 nb = ((flags2 >> 3) & 3) + 1;
114 if ((avctx->bit_rate / avctx->channels) >= 32000)
116 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
119 s->nb_block_sizes = nb + 1;
121 s->nb_block_sizes = 1;
123 /* init rate dependent parameters */
124 s->use_noise_coding = 1;
125 high_freq = avctx->sample_rate * 0.5;
127 /* if version 2, then the rates are normalized */
128 sample_rate1 = avctx->sample_rate;
129 if (s->version == 2) {
130 if (sample_rate1 >= 44100)
131 sample_rate1 = 44100;
132 else if (sample_rate1 >= 22050)
133 sample_rate1 = 22050;
134 else if (sample_rate1 >= 16000)
135 sample_rate1 = 16000;
136 else if (sample_rate1 >= 11025)
137 sample_rate1 = 11025;
138 else if (sample_rate1 >= 8000)
142 bps = (float) avctx->bit_rate /
143 (float) (avctx->channels * avctx->sample_rate);
144 s->byte_offset_bits = av_log2((int) (bps * s->frame_len / 8.0 + 0.5)) + 2;
146 /* compute high frequency value and choose if noise coding should
149 if (avctx->channels == 2)
151 if (sample_rate1 == 44100) {
153 s->use_noise_coding = 0;
155 high_freq = high_freq * 0.4;
156 } else if (sample_rate1 == 22050) {
158 s->use_noise_coding = 0;
159 else if (bps1 >= 0.72)
160 high_freq = high_freq * 0.7;
162 high_freq = high_freq * 0.6;
163 } else if (sample_rate1 == 16000) {
165 high_freq = high_freq * 0.5;
167 high_freq = high_freq * 0.3;
168 } else if (sample_rate1 == 11025)
169 high_freq = high_freq * 0.7;
170 else if (sample_rate1 == 8000) {
172 high_freq = high_freq * 0.5;
174 s->use_noise_coding = 0;
176 high_freq = high_freq * 0.65;
179 high_freq = high_freq * 0.75;
181 high_freq = high_freq * 0.6;
183 high_freq = high_freq * 0.5;
185 ff_dlog(s->avctx, "flags2=0x%x\n", flags2);
186 ff_dlog(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%d block_align=%d\n",
187 s->version, avctx->channels, avctx->sample_rate, avctx->bit_rate,
189 ff_dlog(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
190 bps, bps1, high_freq, s->byte_offset_bits);
191 ff_dlog(s->avctx, "use_noise_coding=%d use_exp_vlc=%d nb_block_sizes=%d\n",
192 s->use_noise_coding, s->use_exp_vlc, s->nb_block_sizes);
194 /* compute the scale factor band sizes for each MDCT block size */
196 int a, b, pos, lpos, k, block_len, i, j, n;
197 const uint8_t *table;
203 for (k = 0; k < s->nb_block_sizes; k++) {
204 block_len = s->frame_len >> k;
206 if (s->version == 1) {
208 for (i = 0; i < 25; i++) {
209 a = ff_wma_critical_freqs[i];
210 b = avctx->sample_rate;
211 pos = ((block_len * 2 * a) + (b >> 1)) / b;
214 s->exponent_bands[0][i] = pos - lpos;
215 if (pos >= block_len) {
221 s->exponent_sizes[0] = i;
223 /* hardcoded tables */
225 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
227 if (avctx->sample_rate >= 44100)
228 table = exponent_band_44100[a];
229 else if (avctx->sample_rate >= 32000)
230 table = exponent_band_32000[a];
231 else if (avctx->sample_rate >= 22050)
232 table = exponent_band_22050[a];
236 for (i = 0; i < n; i++)
237 s->exponent_bands[k][i] = table[i];
238 s->exponent_sizes[k] = n;
242 for (i = 0; i < 25; i++) {
243 a = ff_wma_critical_freqs[i];
244 b = avctx->sample_rate;
245 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
250 s->exponent_bands[k][j++] = pos - lpos;
251 if (pos >= block_len)
255 s->exponent_sizes[k] = j;
259 /* max number of coefs */
260 s->coefs_end[k] = (s->frame_len - ((s->frame_len * 9) / 100)) >> k;
261 /* high freq computation */
262 s->high_band_start[k] = (int) ((block_len * 2 * high_freq) /
263 avctx->sample_rate + 0.5);
264 n = s->exponent_sizes[k];
267 for (i = 0; i < n; i++) {
270 pos += s->exponent_bands[k][i];
272 if (start < s->high_band_start[k])
273 start = s->high_band_start[k];
274 if (end > s->coefs_end[k])
275 end = s->coefs_end[k];
277 s->exponent_high_bands[k][j++] = end - start;
279 s->exponent_high_sizes[k] = j;
286 for (i = 0; i < s->nb_block_sizes; i++) {
287 ff_tlog(s->avctx, "%5d: n=%2d:",
289 s->exponent_sizes[i]);
290 for (j = 0; j < s->exponent_sizes[i]; j++)
291 ff_tlog(s->avctx, " %d", s->exponent_bands[i][j]);
292 ff_tlog(s->avctx, "\n");
297 /* init MDCT windows : simple sine window */
298 for (i = 0; i < s->nb_block_sizes; i++) {
299 ff_init_ff_sine_windows(s->frame_len_bits - i);
300 s->windows[i] = ff_sine_windows[s->frame_len_bits - i];
303 s->reset_block_lengths = 1;
305 if (s->use_noise_coding) {
306 /* init the noise generator */
308 s->noise_mult = 0.02;
310 s->noise_mult = 0.04;
313 for (i = 0; i < NOISE_TAB_SIZE; i++)
314 s->noise_table[i] = 1.0 * s->noise_mult;
320 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * s->noise_mult;
321 for (i = 0; i < NOISE_TAB_SIZE; i++) {
322 seed = seed * 314159 + 1;
323 s->noise_table[i] = (float) ((int) seed) * norm;
329 /* choose the VLC tables for the coefficients */
331 if (avctx->sample_rate >= 32000) {
334 else if (bps1 < 1.16)
337 s->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
338 s->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
339 ret = init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
340 &s->int_table[0], s->coef_vlcs[0]);
344 return init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
345 &s->int_table[1], s->coef_vlcs[1]);
348 int ff_wma_total_gain_to_bits(int total_gain)
352 else if (total_gain < 32)
354 else if (total_gain < 40)
356 else if (total_gain < 45)
362 int ff_wma_end(AVCodecContext *avctx)
364 WMACodecContext *s = avctx->priv_data;
367 for (i = 0; i < s->nb_block_sizes; i++)
368 ff_mdct_end(&s->mdct_ctx[i]);
371 ff_free_vlc(&s->exp_vlc);
372 if (s->use_noise_coding)
373 ff_free_vlc(&s->hgain_vlc);
374 for (i = 0; i < 2; i++) {
375 ff_free_vlc(&s->coef_vlc[i]);
376 av_free(s->run_table[i]);
377 av_free(s->level_table[i]);
378 av_free(s->int_table[i]);
385 * Decode an uncompressed coefficient.
386 * @param bc BitstreamContext
387 * @return the decoded coefficient
389 unsigned int ff_wma_get_large_val(BitstreamContext *bc)
391 /** consumes up to 34 bits */
394 if (bitstream_read_bit(bc)) {
396 if (bitstream_read_bit(bc)) {
398 if (bitstream_read_bit(bc))
402 return bitstream_read(bc, n_bits);
406 * Decode run level compressed coefficients.
407 * @param avctx codec context
408 * @param bc bitstream reader context
409 * @param vlc VLC table for bitstream_read_vlc
410 * @param level_table level codes
411 * @param run_table run codes
412 * @param version 0 for wma1,2 1 for wmapro
413 * @param ptr output buffer
414 * @param offset offset in the output buffer
415 * @param num_coefs number of input coefficients
416 * @param block_len input buffer length (2^n)
417 * @param frame_len_bits number of bits for escaped run codes
418 * @param coef_nb_bits number of bits for escaped level codes
419 * @return 0 on success, -1 otherwise
421 int ff_wma_run_level_decode(AVCodecContext *avctx, BitstreamContext *bc,
422 VLC *vlc, const float *level_table,
423 const uint16_t *run_table, int version,
424 WMACoef *ptr, int offset, int num_coefs,
425 int block_len, int frame_len_bits,
428 int code, level, sign;
429 const uint32_t *ilvl = (const uint32_t *) level_table;
430 uint32_t *iptr = (uint32_t *) ptr;
431 const unsigned int coef_mask = block_len - 1;
432 for (; offset < num_coefs; offset++) {
433 code = bitstream_read_vlc(bc, vlc->table, VLCBITS, VLCMAX);
436 offset += run_table[code];
437 sign = bitstream_read_bit(bc) - 1;
438 iptr[offset & coef_mask] = ilvl[code] ^ sign << 31;
439 } else if (code == 1) {
445 level = bitstream_read(bc, coef_nb_bits);
446 /** NOTE: this is rather suboptimal. reading
447 * block_len_bits would be better */
448 offset += bitstream_read(bc, frame_len_bits);
450 level = ff_wma_get_large_val(bc);
452 if (bitstream_read_bit(bc)) {
453 if (bitstream_read_bit(bc)) {
454 if (bitstream_read_bit(bc)) {
455 av_log(avctx, AV_LOG_ERROR,
456 "broken escape sequence\n");
459 offset += bitstream_read(bc, frame_len_bits) + 4;
461 offset += bitstream_read(bc, 2) + 1;
464 sign = bitstream_read_bit(bc) - 1;
465 ptr[offset & coef_mask] = (level ^ sign) - sign;
468 /** NOTE: EOB can be omitted */
469 if (offset > num_coefs) {
470 av_log(avctx, AV_LOG_ERROR, "overflow in spectral RLE, ignoring\n");