FFmpeg: libavcodec/wma.c Source File

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wma.c
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1/*
2 * WMA compatible codec
3 * Copyright (c) 2002-2007 The FFmpeg Project
4 *
5 * This file is part of FFmpeg.
6 *
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.
11 *
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.
16 *
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
20 */
21
22#include "libavutil/attributes.h"
23#include "libavutil/mem.h"
24
25#include "avcodec.h"
26#include "sinewin.h"
27#include "wma.h"
28#include "wma_common.h"
29#include "wma_freqs.h"
30#include "wmadata.h"
31
32/* XXX: use same run/length optimization as mpeg decoders */
33// FIXME maybe split decode / encode or pass flag
34 static av_cold int init_coef_vlc(VLC *vlc, uint16_t **prun_table,
35 float **plevel_table, uint16_t **pint_table,
36 const CoefVLCTable *vlc_table)
37{
38 int n = vlc_table->n;
39 const uint8_t *table_bits = vlc_table->huffbits;
40 const uint32_t *table_codes = vlc_table->huffcodes;
41 const uint16_t *levels_table = vlc_table->levels;
42 uint16_t *run_table, *int_table;
43 float *flevel_table;
44 int i, l, j, k, level, ret;
45
46 ret = vlc_init(vlc, VLCBITS, n, table_bits, 1, 1, table_codes, 4, 4, 0);
47 if (ret < 0)
48 return ret;
49
50 run_table = av_malloc_array(n, sizeof(uint16_t));
51 flevel_table = av_malloc_array(n, sizeof(*flevel_table));
52 int_table = av_malloc_array(n, sizeof(uint16_t));
53 if (!run_table || !flevel_table || !int_table) {
54 av_freep(&run_table);
55 av_freep(&flevel_table);
56 av_freep(&int_table);
57 return AVERROR(ENOMEM);
58 }
59 i = 2;
60 level = 1;
61 k = 0;
62 while (i < n) {
63 int_table[k] = i;
64 l = levels_table[k++];
65 for (j = 0; j < l; j++) {
66 run_table[i] = j;
67 flevel_table[i] = level;
68 i++;
69 }
70 level++;
71 }
72 *prun_table = run_table;
73 *plevel_table = flevel_table;
74 *pint_table = int_table;
75
76 return 0;
77}
78
79 av_cold int ff_wma_init(AVCodecContext *avctx, int flags2)
80{
81 WMACodecContext *s = avctx->priv_data;
82 int channels = avctx->ch_layout.nb_channels;
83 int i, ret;
84 float bps1, high_freq;
85 float bps;
86 int sample_rate1;
87 int coef_vlc_table;
88
89 if (avctx->sample_rate > 50000 ||
90 channels > 2 ||
91 avctx->bit_rate <= 0)
92 return -1;
93
94
95 if (avctx->codec->id == AV_CODEC_ID_WMAV1)
96 s->version = 1;
97 else
98 s->version = 2;
99
100 /* compute MDCT block size */
101 s->frame_len_bits = ff_wma_get_frame_len_bits(avctx->sample_rate,
102 s->version, 0);
103 s->next_block_len_bits = s->frame_len_bits;
104 s->prev_block_len_bits = s->frame_len_bits;
105 s->block_len_bits = s->frame_len_bits;
106
107 s->frame_len = 1 << s->frame_len_bits;
108 if (s->use_variable_block_len) {
109 int nb_max, nb;
110 nb = ((flags2 >> 3) & 3) + 1;
111 if ((avctx->bit_rate / channels) >= 32000)
112 nb += 2;
113 nb_max = s->frame_len_bits - BLOCK_MIN_BITS;
114 if (nb > nb_max)
115 nb = nb_max;
116 s->nb_block_sizes = nb + 1;
117 } else
118 s->nb_block_sizes = 1;
119
120 /* init rate dependent parameters */
121 s->use_noise_coding = 1;
122 high_freq = avctx->sample_rate * 0.5;
123
124 /* if version 2, then the rates are normalized */
125 sample_rate1 = avctx->sample_rate;
126 if (s->version == 2) {
127 if (sample_rate1 >= 44100)
128 sample_rate1 = 44100;
129 else if (sample_rate1 >= 22050)
130 sample_rate1 = 22050;
131 else if (sample_rate1 >= 16000)
132 sample_rate1 = 16000;
133 else if (sample_rate1 >= 11025)
134 sample_rate1 = 11025;
135 else if (sample_rate1 >= 8000)
136 sample_rate1 = 8000;
137 }
138
139 bps = (float) avctx->bit_rate /
140 (float) (channels * avctx->sample_rate);
141 s->byte_offset_bits = av_log2((int) (bps * s->frame_len / 8.0 + 0.5)) + 2;
142 if (s->byte_offset_bits + 3 > MIN_CACHE_BITS) {
143 av_log(avctx, AV_LOG_ERROR, "byte_offset_bits %d is too large\n", s->byte_offset_bits);
145 }
146
147 /* compute high frequency value and choose if noise coding should
148 * be activated */
149 bps1 = bps;
150 if (channels == 2)
151 bps1 = bps * 1.6;
152 if (sample_rate1 == 44100) {
153 if (bps1 >= 0.61)
154 s->use_noise_coding = 0;
155 else
156 high_freq = high_freq * 0.4;
157 } else if (sample_rate1 == 22050) {
158 if (bps1 >= 1.16)
159 s->use_noise_coding = 0;
160 else if (bps1 >= 0.72)
161 high_freq = high_freq * 0.7;
162 else
163 high_freq = high_freq * 0.6;
164 } else if (sample_rate1 == 16000) {
165 if (bps > 0.5)
166 high_freq = high_freq * 0.5;
167 else
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) {
172 if (bps <= 0.625)
173 high_freq = high_freq * 0.5;
174 else if (bps > 0.75)
175 s->use_noise_coding = 0;
176 else
177 high_freq = high_freq * 0.65;
178 } else {
179 if (bps >= 0.8)
180 high_freq = high_freq * 0.75;
181 else if (bps >= 0.6)
182 high_freq = high_freq * 0.6;
183 else
184 high_freq = high_freq * 0.5;
185 }
186 ff_dlog(s->avctx, "flags2=0x%x\n", flags2);
187 ff_dlog(s->avctx, "version=%d channels=%d sample_rate=%d bitrate=%"PRId64" block_align=%d\n",
188 s->version, channels, avctx->sample_rate, avctx->bit_rate,
189 avctx->block_align);
190 ff_dlog(s->avctx, "bps=%f bps1=%f high_freq=%f bitoffset=%d\n",
191 bps, bps1, high_freq, s->byte_offset_bits);
192 ff_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);
194
195 /* compute the scale factor band sizes for each MDCT block size */
196 {
197 int a, b, pos, lpos, k, block_len, i, j, n;
198 const uint8_t *table;
199
200 if (s->version == 1)
201 s->coefs_start = 3;
202 else
203 s->coefs_start = 0;
204 for (k = 0; k < s->nb_block_sizes; k++) {
205 block_len = s->frame_len >> k;
206
207 if (s->version == 1) {
208 lpos = 0;
209 for (i = 0; i < 25; i++) {
211 b = avctx->sample_rate;
212 pos = ((block_len * 2 * a) + (b >> 1)) / b;
213 if (pos > block_len)
214 pos = block_len;
215 s->exponent_bands[0][i] = pos - lpos;
216 if (pos >= block_len) {
217 i++;
218 break;
219 }
220 lpos = pos;
221 }
222 s->exponent_sizes[0] = i;
223 } else {
224 /* hardcoded tables */
225 table = NULL;
226 a = s->frame_len_bits - BLOCK_MIN_BITS - k;
227 if (a < 3) {
228 if (avctx->sample_rate >= 44100)
230 else if (avctx->sample_rate >= 32000)
232 else if (avctx->sample_rate >= 22050)
234 }
235 if (table) {
236 n = *table++;
237 for (i = 0; i < n; i++)
238 s->exponent_bands[k][i] = table[i];
239 s->exponent_sizes[k] = n;
240 } else {
241 j = 0;
242 lpos = 0;
243 for (i = 0; i < 25; i++) {
245 b = avctx->sample_rate;
246 pos = ((block_len * 2 * a) + (b << 1)) / (4 * b);
247 pos <<= 2;
248 if (pos > block_len)
249 pos = block_len;
250 if (pos > lpos)
251 s->exponent_bands[k][j++] = pos - lpos;
252 if (pos >= block_len)
253 break;
254 lpos = pos;
255 }
256 s->exponent_sizes[k] = j;
257 }
258 }
259
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];
266 j = 0;
267 pos = 0;
268 for (i = 0; i < n; i++) {
269 int start, end;
270 start = pos;
271 pos += s->exponent_bands[k][i];
272 end = pos;
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];
277 if (end > start)
278 s->exponent_high_bands[k][j++] = end - start;
279 }
280 s->exponent_high_sizes[k] = j;
281 }
282 }
283
284#ifdef TRACE
285 {
286 int i, j;
287 for (i = 0; i < s->nb_block_sizes; i++) {
288 ff_tlog(s->avctx, "%5d: n=%2d:",
289 s->frame_len >> i,
290 s->exponent_sizes[i]);
291 for (j = 0; j < s->exponent_sizes[i]; j++)
292 ff_tlog(s->avctx, " %d", s->exponent_bands[i][j]);
293 ff_tlog(s->avctx, "\n");
294 }
295 }
296#endif /* TRACE */
297
298 /* init MDCT windows : simple sine window */
299 for (i = 0; i < s->nb_block_sizes; i++) {
300 ff_init_ff_sine_windows(s->frame_len_bits - i);
301 s->windows[i] = ff_sine_windows[s->frame_len_bits - i];
302 }
303
304 s->reset_block_lengths = 1;
305
306 if (s->use_noise_coding) {
307 /* init the noise generator */
308 if (s->use_exp_vlc)
309 s->noise_mult = 0.02;
310 else
311 s->noise_mult = 0.04;
312
313#ifdef TRACE
314 for (i = 0; i < NOISE_TAB_SIZE; i++)
315 s->noise_table[i] = 1.0 * s->noise_mult;
316#else
317 {
318 unsigned int seed;
319 float norm;
320 seed = 1;
321 norm = (1.0 / (float) (1LL << 31)) * sqrt(3) * s->noise_mult;
322 for (i = 0; i < NOISE_TAB_SIZE; i++) {
323 seed = seed * 314159 + 1;
324 s->noise_table[i] = (float) ((int) seed) * norm;
325 }
326 }
327#endif /* TRACE */
328 }
329
331 if (!s->fdsp)
332 return AVERROR(ENOMEM);
333
334 /* choose the VLC tables for the coefficients */
335 coef_vlc_table = 2;
336 if (avctx->sample_rate >= 32000) {
337 if (bps1 < 0.72)
338 coef_vlc_table = 0;
339 else if (bps1 < 1.16)
340 coef_vlc_table = 1;
341 }
342 s->coef_vlcs[0] = &coef_vlcs[coef_vlc_table * 2];
343 s->coef_vlcs[1] = &coef_vlcs[coef_vlc_table * 2 + 1];
344 ret = init_coef_vlc(&s->coef_vlc[0], &s->run_table[0], &s->level_table[0],
345 &s->int_table[0], s->coef_vlcs[0]);
346 if (ret < 0)
347 return ret;
348
349 return init_coef_vlc(&s->coef_vlc[1], &s->run_table[1], &s->level_table[1],
350 &s->int_table[1], s->coef_vlcs[1]);
351}
352
353 int ff_wma_total_gain_to_bits(int total_gain)
354{
355 if (total_gain < 15)
356 return 13;
357 else if (total_gain < 32)
358 return 12;
359 else if (total_gain < 40)
360 return 11;
361 else if (total_gain < 45)
362 return 10;
363 else
364 return 9;
365}
366
368{
369 WMACodecContext *s = avctx->priv_data;
370 int i;
371
372 for (i = 0; i < s->nb_block_sizes; i++)
373 av_tx_uninit(&s->mdct_ctx[i]);
374
375 if (s->use_exp_vlc)
376 ff_vlc_free(&s->exp_vlc);
377 if (s->use_noise_coding)
378 ff_vlc_free(&s->hgain_vlc);
379 for (i = 0; i < 2; i++) {
380 ff_vlc_free(&s->coef_vlc[i]);
381 av_freep(&s->run_table[i]);
382 av_freep(&s->level_table[i]);
383 av_freep(&s->int_table[i]);
384 }
385 av_freep(&s->fdsp);
386
387 return 0;
388}
389
390/**
391 * Decode an uncompressed coefficient.
392 * @param gb GetBitContext
393 * @return the decoded coefficient
394 */
396{
397 /** consumes up to 34 bits */
398 int n_bits = 8;
399 /** decode length */
400 if (get_bits1(gb)) {
401 n_bits += 8;
402 if (get_bits1(gb)) {
403 n_bits += 8;
404 if (get_bits1(gb))
405 n_bits += 7;
406 }
407 }
408 return get_bits_long(gb, n_bits);
409}
410
411/**
412 * Decode run level compressed coefficients.
413 * @param avctx codec context
414 * @param gb bitstream reader context
415 * @param vlc vlc table for get_vlc2
416 * @param level_table level codes
417 * @param run_table run codes
418 * @param version 0 for wma1,2 1 for wmapro
419 * @param ptr output buffer
420 * @param offset offset in the output buffer
421 * @param num_coefs number of input coefficients
422 * @param block_len input buffer length (2^n)
423 * @param frame_len_bits number of bits for escaped run codes
424 * @param coef_nb_bits number of bits for escaped level codes
425 * @return 0 on success, -1 otherwise
426 */
428 const VLCElem *vlc, const float *level_table,
429 const uint16_t *run_table, int version,
430 WMACoef *ptr, int offset, int num_coefs,
431 int block_len, int frame_len_bits,
432 int coef_nb_bits)
433{
434 int code, level, sign;
435 const uint32_t *ilvl = (const uint32_t *) level_table;
436 uint32_t *iptr = (uint32_t *) ptr;
437 const unsigned int coef_mask = block_len - 1;
438 for (; offset < num_coefs; offset++) {
439 code = get_vlc2(gb, vlc, VLCBITS, VLCMAX);
440 if (code > 1) {
441 /** normal code */
442 offset += run_table[code];
443 sign = get_bits1(gb) - 1;
444 iptr[offset & coef_mask] = ilvl[code] ^ (sign & 0x80000000);
445 } else if (code == 1) {
446 /** EOB */
447 break;
448 } else {
449 /** escape */
450 if (!version) {
451 level = get_bits(gb, coef_nb_bits);
452 /** NOTE: this is rather suboptimal. reading
453 * block_len_bits would be better */
454 offset += get_bits(gb, frame_len_bits);
455 } else {
457 /** escape decode */
458 if (get_bits1(gb)) {
459 if (get_bits1(gb)) {
460 if (get_bits1(gb)) {
461 av_log(avctx, AV_LOG_ERROR,
462 "broken escape sequence\n");
463 return AVERROR_INVALIDDATA;
464 } else
465 offset += get_bits(gb, frame_len_bits) + 4;
466 } else
467 offset += get_bits(gb, 2) + 1;
468 }
469 }
470 sign = get_bits1(gb) - 1;
471 ptr[offset & coef_mask] = (level ^ sign) - sign;
472 }
473 }
474 /** NOTE: EOB can be omitted */
475 if (offset > num_coefs) {
476 av_log(avctx, AV_LOG_ERROR,
477 "overflow (%d > %d) in spectral RLE, ignoring\n",
478 offset,
479 num_coefs
480 );
481 return AVERROR_INVALIDDATA;
482 }
483
484 return 0;
485}
float
channels
Definition aptx.h:31
Libavcodec external API header.
i
#define i(width, name, range_min, range_max)
Definition cbs_h264.c:63
s
#define s(width, name)
Definition cbs_vp9.c:198
#define NULL
Definition coverity.c:32
static unsigned int get_bits_long(GetBitContext *s, int n)
Read 0-32 bits.
Definition get_bits.h:424
static av_always_inline int get_vlc2(GetBitContext *s, const VLCElem *table, int bits, int max_depth)
Parse a vlc code.
Definition get_bits.h:645
static unsigned int get_bits1(GetBitContext *s)
Definition get_bits.h:391
#define MIN_CACHE_BITS
Definition get_bits.h:167
static unsigned int get_bits(GetBitContext *s, int n)
Read 1-25 bits.
Definition get_bits.h:337
#define AV_CODEC_FLAG_BITEXACT
Use only bitexact stuff (except (I)DCT).
Definition avcodec.h:322
@ AV_CODEC_ID_WMAV1
Definition codec_id.h:460
#define AVERROR_PATCHWELCOME
Not yet implemented in FFmpeg, patches welcome.
Definition error.h:64
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition error.h:61
#define AVERROR(e)
Definition error.h:45
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition log.h:210
a
int a
b
#define b
Definition input.c:43
#define av_log2
Definition intmath.h:84
unsigned offset
Definition libaomenc.c:763
Macro definitions for various function/variable attributes.
#define av_cold
Definition attributes.h:117
av_cold AVFloatDSPContext * avpriv_float_dsp_alloc(int bit_exact)
Allocate a float DSP context.
Definition float_dsp.c:135
version
Definition libkvazaar.c:313
Memory handling functions.
unsigned bps
Definition movenc.c:2088
static const uint16_t table[]
Definition prosumer.c:203
void ff_init_ff_sine_windows(int index)
initialize the specified entry of ff_sine_windows
SINETABLE_CONST float *const ff_sine_windows[]
const uint8_t * code
Definition spdifenc.c:433
unsigned int pos
Definition spdifenc.c:431
int nb_channels
Number of channels in this layout.
main external API structure.
Definition avcodec.h:443
AVChannelLayout ch_layout
Audio channel layout.
Definition avcodec.h:1055
int64_t bit_rate
the average bitrate
Definition avcodec.h:493
const struct AVCodec * codec
Definition avcodec.h:452
int sample_rate
samples per second
Definition avcodec.h:1040
int flags
AV_CODEC_FLAG_*.
Definition avcodec.h:500
int block_align
number of bytes per packet if constant and known or 0 Used by some WAV based audio codecs.
Definition avcodec.h:1075
void * priv_data
Definition avcodec.h:470
enum AVCodecID id
Definition codec.h:189
const uint32_t * huffcodes
VLC bit values.
Definition wma.h:63
const uint8_t * huffbits
VLC bit size.
Definition wma.h:64
int n
total number of codes
Definition wma.h:61
const uint16_t * levels
table to build run/level tables
Definition wma.h:65
Definition vlc.h:32
Definition vlc.h:50
uint8_t level
Definition svq3.c:208
#define av_malloc_array(a, b)
#define ff_dlog(a,...)
#define av_freep(p)
#define ff_tlog(a,...)
#define av_log(a,...)
av_cold void av_tx_uninit(AVTXContext **ctx)
Frees a context and sets *ctx to NULL, does nothing when *ctx == NULL.
Definition tx.c:295
static unsigned int seed
Definition videogen.c:78
void ff_vlc_free(VLC *vlc)
Definition vlc.c:580
#define vlc_init(vlc, nb_bits, nb_codes, bits, bits_wrap, bits_size, codes, codes_wrap, codes_size, flags)
Definition vlc.h:70
int ff_wma_total_gain_to_bits(int total_gain)
Definition wma.c:353
av_cold int ff_wma_end(AVCodecContext *avctx)
Definition wma.c:367
static av_cold int init_coef_vlc(VLC *vlc, uint16_t **prun_table, float **plevel_table, uint16_t **pint_table, const CoefVLCTable *vlc_table)
Definition wma.c:34
av_cold int ff_wma_init(AVCodecContext *avctx, int flags2)
Definition wma.c:79
unsigned int ff_wma_get_large_val(GetBitContext *gb)
Decode an uncompressed coefficient.
Definition wma.c:395
int ff_wma_run_level_decode(AVCodecContext *avctx, GetBitContext *gb, const VLCElem *vlc, const float *level_table, const uint16_t *run_table, int version, WMACoef *ptr, int offset, int num_coefs, int block_len, int frame_len_bits, int coef_nb_bits)
Decode run level compressed coefficients.
Definition wma.c:427
#define BLOCK_MIN_BITS
Definition wma.h:34
#define VLCBITS
Definition wma.h:55
#define NOISE_TAB_SIZE
Definition wma.h:50
float WMACoef
type for decoded coefficients, int16_t would be enough for wma 1/2
Definition wma.h:58
#define VLCMAX
Definition wma.h:56
av_cold int ff_wma_get_frame_len_bits(int sample_rate, int version, unsigned int decode_flags)
Get the samples per frame for this stream.
Definition wma_common.c:32
const uint16_t ff_wma_critical_freqs[25]
Definition wma_freqs.c:23
Various WMA tables.
static const uint8_t exponent_band_32000[3][25]
Definition wmadata.h:42
static const uint8_t exponent_band_22050[3][25]
Definition wmadata.h:35
static const CoefVLCTable coef_vlcs[6]
Definition wmadata.h:1371
static const uint8_t exponent_band_44100[3][25]
Definition wmadata.h:48
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