wmaenc.c
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1 /*
2  * WMA compatible encoder
3  * Copyright (c) 2007 Michael Niedermayer
4  *
5  * This file is part of Libav.
6  *
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.
11  *
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.
16  *
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
20  */
21 
22 #include "avcodec.h"
23 #include "internal.h"
24 #include "wma.h"
25 
26 #undef NDEBUG
27 #include <assert.h>
28 
29 
30 static int encode_init(AVCodecContext * avctx){
31  WMACodecContext *s = avctx->priv_data;
32  int i, flags1, flags2, block_align;
33  uint8_t *extradata;
34 
35  s->avctx = avctx;
36 
37  if(avctx->channels > MAX_CHANNELS) {
38  av_log(avctx, AV_LOG_ERROR, "too many channels: got %i, need %i or fewer",
39  avctx->channels, MAX_CHANNELS);
40  return AVERROR(EINVAL);
41  }
42 
43  if (avctx->sample_rate > 48000) {
44  av_log(avctx, AV_LOG_ERROR, "sample rate is too high: %d > 48kHz",
45  avctx->sample_rate);
46  return AVERROR(EINVAL);
47  }
48 
49  if(avctx->bit_rate < 24*1000) {
50  av_log(avctx, AV_LOG_ERROR, "bitrate too low: got %i, need 24000 or higher\n",
51  avctx->bit_rate);
52  return AVERROR(EINVAL);
53  }
54 
55  /* extract flag infos */
56  flags1 = 0;
57  flags2 = 1;
58  if (avctx->codec->id == AV_CODEC_ID_WMAV1) {
59  extradata= av_malloc(4);
60  avctx->extradata_size= 4;
61  AV_WL16(extradata, flags1);
62  AV_WL16(extradata+2, flags2);
63  } else if (avctx->codec->id == AV_CODEC_ID_WMAV2) {
64  extradata= av_mallocz(10);
65  avctx->extradata_size= 10;
66  AV_WL32(extradata, flags1);
67  AV_WL16(extradata+4, flags2);
68  }else
69  assert(0);
70  avctx->extradata= extradata;
71  s->use_exp_vlc = flags2 & 0x0001;
72  s->use_bit_reservoir = flags2 & 0x0002;
73  s->use_variable_block_len = flags2 & 0x0004;
74  if (avctx->channels == 2)
75  s->ms_stereo = 1;
76 
77  ff_wma_init(avctx, flags2);
78 
79  /* init MDCT */
80  for(i = 0; i < s->nb_block_sizes; i++)
81  ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 0, 1.0);
82 
83  block_align = avctx->bit_rate * (int64_t)s->frame_len /
84  (avctx->sample_rate * 8);
85  block_align = FFMIN(block_align, MAX_CODED_SUPERFRAME_SIZE);
86  avctx->block_align = block_align;
87  avctx->bit_rate = avctx->block_align * 8LL * avctx->sample_rate /
88  s->frame_len;
89  avctx->frame_size = avctx->delay = s->frame_len;
90 
91 #if FF_API_OLD_ENCODE_AUDIO
92  avctx->coded_frame = &s->frame;
94 #endif
95 
96  return 0;
97 }
98 
99 
100 static void apply_window_and_mdct(AVCodecContext * avctx, const AVFrame *frame)
101 {
102  WMACodecContext *s = avctx->priv_data;
103  float **audio = (float **)frame->extended_data;
104  int len = frame->nb_samples;
105  int window_index= s->frame_len_bits - s->block_len_bits;
106  FFTContext *mdct = &s->mdct_ctx[window_index];
107  int ch;
108  const float * win = s->windows[window_index];
109  int window_len = 1 << s->block_len_bits;
110  float n = 2.0 * 32768.0 / window_len;
111 
112  for (ch = 0; ch < avctx->channels; ch++) {
113  memcpy(s->output, s->frame_out[ch], window_len * sizeof(*s->output));
114  s->fdsp.vector_fmul_scalar(s->frame_out[ch], audio[ch], n, len);
115  s->dsp.vector_fmul_reverse(&s->output[window_len], s->frame_out[ch], win, len);
116  s->fdsp.vector_fmul(s->frame_out[ch], s->frame_out[ch], win, len);
117  mdct->mdct_calc(mdct, s->coefs[ch], s->output);
118  }
119 }
120 
121 //FIXME use for decoding too
122 static void init_exp(WMACodecContext *s, int ch, const int *exp_param){
123  int n;
124  const uint16_t *ptr;
125  float v, *q, max_scale, *q_end;
126 
127  ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
128  q = s->exponents[ch];
129  q_end = q + s->block_len;
130  max_scale = 0;
131  while (q < q_end) {
132  /* XXX: use a table */
133  v = pow(10, *exp_param++ * (1.0 / 16.0));
134  max_scale= FFMAX(max_scale, v);
135  n = *ptr++;
136  do {
137  *q++ = v;
138  } while (--n);
139  }
140  s->max_exponent[ch] = max_scale;
141 }
142 
143 static void encode_exp_vlc(WMACodecContext *s, int ch, const int *exp_param){
144  int last_exp;
145  const uint16_t *ptr;
146  float *q, *q_end;
147 
148  ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
149  q = s->exponents[ch];
150  q_end = q + s->block_len;
151  if (s->version == 1) {
152  last_exp= *exp_param++;
153  assert(last_exp-10 >= 0 && last_exp-10 < 32);
154  put_bits(&s->pb, 5, last_exp - 10);
155  q+= *ptr++;
156  }else
157  last_exp = 36;
158  while (q < q_end) {
159  int exp = *exp_param++;
160  int code = exp - last_exp + 60;
161  assert(code >= 0 && code < 120);
163  /* XXX: use a table */
164  q+= *ptr++;
165  last_exp= exp;
166  }
167 }
168 
169 static int encode_block(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], int total_gain){
170  int v, bsize, ch, coef_nb_bits, parse_exponents;
171  float mdct_norm;
172  int nb_coefs[MAX_CHANNELS];
173  static const int fixed_exp[25]={20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20,20};
174 
175  //FIXME remove duplication relative to decoder
176  if (s->use_variable_block_len) {
177  assert(0); //FIXME not implemented
178  }else{
179  /* fixed block len */
183  }
184 
185  s->block_len = 1 << s->block_len_bits;
186 // assert((s->block_pos + s->block_len) <= s->frame_len);
187  bsize = s->frame_len_bits - s->block_len_bits;
188 
189  //FIXME factor
190  v = s->coefs_end[bsize] - s->coefs_start;
191  for (ch = 0; ch < s->avctx->channels; ch++)
192  nb_coefs[ch] = v;
193  {
194  int n4 = s->block_len / 2;
195  mdct_norm = 1.0 / (float)n4;
196  if (s->version == 1) {
197  mdct_norm *= sqrt(n4);
198  }
199  }
200 
201  if (s->avctx->channels == 2) {
202  put_bits(&s->pb, 1, !!s->ms_stereo);
203  }
204 
205  for (ch = 0; ch < s->avctx->channels; ch++) {
206  s->channel_coded[ch] = 1; //FIXME only set channel_coded when needed, instead of always
207  if (s->channel_coded[ch]) {
208  init_exp(s, ch, fixed_exp);
209  }
210  }
211 
212  for (ch = 0; ch < s->avctx->channels; ch++) {
213  if (s->channel_coded[ch]) {
214  WMACoef *coefs1;
215  float *coefs, *exponents, mult;
216  int i, n;
217 
218  coefs1 = s->coefs1[ch];
219  exponents = s->exponents[ch];
220  mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
221  mult *= mdct_norm;
222  coefs = src_coefs[ch];
223  if (s->use_noise_coding && 0) {
224  assert(0); //FIXME not implemented
225  } else {
226  coefs += s->coefs_start;
227  n = nb_coefs[ch];
228  for(i = 0;i < n; i++){
229  double t= *coefs++ / (exponents[i] * mult);
230  if(t<-32768 || t>32767)
231  return -1;
232 
233  coefs1[i] = lrint(t);
234  }
235  }
236  }
237  }
238 
239  v = 0;
240  for (ch = 0; ch < s->avctx->channels; ch++) {
241  int a = s->channel_coded[ch];
242  put_bits(&s->pb, 1, a);
243  v |= a;
244  }
245 
246  if (!v)
247  return 1;
248 
249  for(v= total_gain-1; v>=127; v-= 127)
250  put_bits(&s->pb, 7, 127);
251  put_bits(&s->pb, 7, v);
252 
253  coef_nb_bits= ff_wma_total_gain_to_bits(total_gain);
254 
255  if (s->use_noise_coding) {
256  for (ch = 0; ch < s->avctx->channels; ch++) {
257  if (s->channel_coded[ch]) {
258  int i, n;
259  n = s->exponent_high_sizes[bsize];
260  for(i=0;i<n;i++) {
261  put_bits(&s->pb, 1, s->high_band_coded[ch][i]= 0);
262  if (0)
263  nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
264  }
265  }
266  }
267  }
268 
269  parse_exponents = 1;
270  if (s->block_len_bits != s->frame_len_bits) {
271  put_bits(&s->pb, 1, parse_exponents);
272  }
273 
274  if (parse_exponents) {
275  for (ch = 0; ch < s->avctx->channels; ch++) {
276  if (s->channel_coded[ch]) {
277  if (s->use_exp_vlc) {
278  encode_exp_vlc(s, ch, fixed_exp);
279  } else {
280  assert(0); //FIXME not implemented
281 // encode_exp_lsp(s, ch);
282  }
283  }
284  }
285  } else {
286  assert(0); //FIXME not implemented
287  }
288 
289  for (ch = 0; ch < s->avctx->channels; ch++) {
290  if (s->channel_coded[ch]) {
291  int run, tindex;
292  WMACoef *ptr, *eptr;
293  tindex = (ch == 1 && s->ms_stereo);
294  ptr = &s->coefs1[ch][0];
295  eptr = ptr + nb_coefs[ch];
296 
297  run=0;
298  for(;ptr < eptr; ptr++){
299  if(*ptr){
300  int level= *ptr;
301  int abs_level= FFABS(level);
302  int code= 0;
303  if(abs_level <= s->coef_vlcs[tindex]->max_level){
304  if(run < s->coef_vlcs[tindex]->levels[abs_level-1])
305  code= run + s->int_table[tindex][abs_level-1];
306  }
307 
308  assert(code < s->coef_vlcs[tindex]->n);
309  put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[code], s->coef_vlcs[tindex]->huffcodes[code]);
310 
311  if(code == 0){
312  if(1<<coef_nb_bits <= abs_level)
313  return -1;
314 
315  put_bits(&s->pb, coef_nb_bits, abs_level);
316  put_bits(&s->pb, s->frame_len_bits, run);
317  }
318  put_bits(&s->pb, 1, level < 0); //FIXME the sign is fliped somewhere
319  run=0;
320  }else{
321  run++;
322  }
323  }
324  if(run)
325  put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[1], s->coef_vlcs[tindex]->huffcodes[1]);
326  }
327  if (s->version == 1 && s->avctx->channels >= 2) {
329  }
330  }
331  return 0;
332 }
333 
334 static int encode_frame(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], uint8_t *buf, int buf_size, int total_gain){
335  init_put_bits(&s->pb, buf, buf_size);
336 
337  if (s->use_bit_reservoir) {
338  assert(0);//FIXME not implemented
339  }else{
340  if(encode_block(s, src_coefs, total_gain) < 0)
341  return INT_MAX;
342  }
343 
345 
346  return put_bits_count(&s->pb) / 8 - s->avctx->block_align;
347 }
348 
349 static int encode_superframe(AVCodecContext *avctx, AVPacket *avpkt,
350  const AVFrame *frame, int *got_packet_ptr)
351 {
352  WMACodecContext *s = avctx->priv_data;
353  int i, total_gain, ret;
354 
355  s->block_len_bits= s->frame_len_bits; //required by non variable block len
356  s->block_len = 1 << s->block_len_bits;
357 
358  apply_window_and_mdct(avctx, frame);
359 
360  if (s->ms_stereo) {
361  float a, b;
362  int i;
363 
364  for(i = 0; i < s->block_len; i++) {
365  a = s->coefs[0][i]*0.5;
366  b = s->coefs[1][i]*0.5;
367  s->coefs[0][i] = a + b;
368  s->coefs[1][i] = a - b;
369  }
370  }
371 
372  if ((ret = ff_alloc_packet(avpkt, 2 * MAX_CODED_SUPERFRAME_SIZE))) {
373  av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
374  return ret;
375  }
376 
377 #if 1
378  total_gain= 128;
379  for(i=64; i; i>>=1){
380  int error = encode_frame(s, s->coefs, avpkt->data, avpkt->size,
381  total_gain - i);
382  if(error<0)
383  total_gain-= i;
384  }
385 #else
386  total_gain= 90;
387  best = encode_frame(s, s->coefs, avpkt->data, avpkt->size, total_gain);
388  for(i=32; i; i>>=1){
389  int scoreL = encode_frame(s, s->coefs, avpkt->data, avpkt->size, total_gain - i);
390  int scoreR = encode_frame(s, s->coefs, avpkt->data, avpkt->size, total_gain + i);
391  av_log(NULL, AV_LOG_ERROR, "%d %d %d (%d)\n", scoreL, best, scoreR, total_gain);
392  if(scoreL < FFMIN(best, scoreR)){
393  best = scoreL;
394  total_gain -= i;
395  }else if(scoreR < best){
396  best = scoreR;
397  total_gain += i;
398  }
399  }
400 #endif
401 
402  if ((i = encode_frame(s, s->coefs, avpkt->data, avpkt->size, total_gain)) >= 0) {
403  av_log(avctx, AV_LOG_ERROR, "required frame size too large. please "
404  "use a higher bit rate.\n");
405  return AVERROR(EINVAL);
406  }
407  assert((put_bits_count(&s->pb) & 7) == 0);
408  while (i++)
409  put_bits(&s->pb, 8, 'N');
410 
411  flush_put_bits(&s->pb);
412 
413  if (frame->pts != AV_NOPTS_VALUE)
414  avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->delay);
415 
416  avpkt->size = avctx->block_align;
417  *got_packet_ptr = 1;
418  return 0;
419 }
420 
422  .name = "wmav1",
423  .type = AVMEDIA_TYPE_AUDIO,
424  .id = AV_CODEC_ID_WMAV1,
425  .priv_data_size = sizeof(WMACodecContext),
426  .init = encode_init,
427  .encode2 = encode_superframe,
428  .close = ff_wma_end,
429  .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_FLTP,
431  .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"),
432 };
433 
435  .name = "wmav2",
436  .type = AVMEDIA_TYPE_AUDIO,
437  .id = AV_CODEC_ID_WMAV2,
438  .priv_data_size = sizeof(WMACodecContext),
439  .init = encode_init,
440  .encode2 = encode_superframe,
441  .close = ff_wma_end,
442  .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_FLTP,
444  .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"),
445 };