2 * WMA compatible encoder
3 * Copyright (c) 2007 Michael Niedermayer
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
29 static int encode_init(AVCodecContext * avctx){
30 WMACodecContext *s = avctx->priv_data;
31 int i, flags1, flags2;
36 if(avctx->channels > MAX_CHANNELS) {
37 av_log(avctx, AV_LOG_ERROR, "too many channels: got %i, need %i or fewer",
38 avctx->channels, MAX_CHANNELS);
39 return AVERROR(EINVAL);
42 if (avctx->sample_rate > 48000) {
43 av_log(avctx, AV_LOG_ERROR, "sample rate is too high: %d > 48kHz",
45 return AVERROR(EINVAL);
48 if(avctx->bit_rate < 24*1000) {
49 av_log(avctx, AV_LOG_ERROR, "bitrate too low: got %i, need 24000 or higher\n",
51 return AVERROR(EINVAL);
54 /* extract flag infos */
57 if (avctx->codec->id == CODEC_ID_WMAV1) {
58 extradata= av_malloc(4);
59 avctx->extradata_size= 4;
60 AV_WL16(extradata, flags1);
61 AV_WL16(extradata+2, flags2);
62 } else if (avctx->codec->id == CODEC_ID_WMAV2) {
63 extradata= av_mallocz(10);
64 avctx->extradata_size= 10;
65 AV_WL32(extradata, flags1);
66 AV_WL16(extradata+4, flags2);
69 avctx->extradata= extradata;
70 s->use_exp_vlc = flags2 & 0x0001;
71 s->use_bit_reservoir = flags2 & 0x0002;
72 s->use_variable_block_len = flags2 & 0x0004;
74 ff_wma_init(avctx, flags2);
77 for(i = 0; i < s->nb_block_sizes; i++)
78 ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 0, 1.0);
80 s->block_align = avctx->bit_rate * (int64_t)s->frame_len /
81 (avctx->sample_rate * 8);
82 s->block_align = FFMIN(s->block_align, MAX_CODED_SUPERFRAME_SIZE);
83 avctx->block_align = s->block_align;
84 avctx->bit_rate = avctx->block_align * 8LL * avctx->sample_rate /
86 //av_log(NULL, AV_LOG_ERROR, "%d %d %d %d\n", s->block_align, avctx->bit_rate, s->frame_len, avctx->sample_rate);
87 avctx->frame_size= s->frame_len;
93 static void apply_window_and_mdct(AVCodecContext * avctx, const signed short * audio, int len) {
94 WMACodecContext *s = avctx->priv_data;
95 int window_index= s->frame_len_bits - s->block_len_bits;
96 FFTContext *mdct = &s->mdct_ctx[window_index];
98 const float * win = s->windows[window_index];
99 int window_len = 1 << s->block_len_bits;
100 float n = window_len/2;
102 for (channel = 0; channel < avctx->channels; channel++) {
103 memcpy(s->output, s->frame_out[channel], sizeof(float)*window_len);
105 for (i = 0; i < len; i++, j += avctx->channels){
106 s->output[i+window_len] = audio[j] / n * win[window_len - i - 1];
107 s->frame_out[channel][i] = audio[j] / n * win[i];
109 mdct->mdct_calc(mdct, s->coefs[channel], s->output);
113 //FIXME use for decoding too
114 static void init_exp(WMACodecContext *s, int ch, const int *exp_param){
117 float v, *q, max_scale, *q_end;
119 ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
120 q = s->exponents[ch];
121 q_end = q + s->block_len;
124 /* XXX: use a table */
125 v = pow(10, *exp_param++ * (1.0 / 16.0));
126 max_scale= FFMAX(max_scale, v);
132 s->max_exponent[ch] = max_scale;
135 static void encode_exp_vlc(WMACodecContext *s, int ch, const int *exp_param){
140 ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
141 q = s->exponents[ch];
142 q_end = q + s->block_len;
143 if (s->version == 1) {
144 last_exp= *exp_param++;
145 assert(last_exp-10 >= 0 && last_exp-10 < 32);
146 put_bits(&s->pb, 5, last_exp - 10);
151 int exp = *exp_param++;
152 int code = exp - last_exp + 60;
153 assert(code >= 0 && code < 120);
154 put_bits(&s->pb, ff_aac_scalefactor_bits[code], ff_aac_scalefactor_code[code]);
155 /* XXX: use a table */
161 static int encode_block(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], int total_gain){
162 int v, bsize, ch, coef_nb_bits, parse_exponents;
164 int nb_coefs[MAX_CHANNELS];
165 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};
167 //FIXME remove duplication relative to decoder
168 if (s->use_variable_block_len) {
169 assert(0); //FIXME not implemented
171 /* fixed block len */
172 s->next_block_len_bits = s->frame_len_bits;
173 s->prev_block_len_bits = s->frame_len_bits;
174 s->block_len_bits = s->frame_len_bits;
177 s->block_len = 1 << s->block_len_bits;
178 // assert((s->block_pos + s->block_len) <= s->frame_len);
179 bsize = s->frame_len_bits - s->block_len_bits;
182 v = s->coefs_end[bsize] - s->coefs_start;
183 for(ch = 0; ch < s->nb_channels; ch++)
186 int n4 = s->block_len / 2;
187 mdct_norm = 1.0 / (float)n4;
188 if (s->version == 1) {
189 mdct_norm *= sqrt(n4);
193 if (s->nb_channels == 2) {
194 put_bits(&s->pb, 1, s->ms_stereo= 1);
197 for(ch = 0; ch < s->nb_channels; ch++) {
198 s->channel_coded[ch] = 1; //FIXME only set channel_coded when needed, instead of always
199 if (s->channel_coded[ch]) {
200 init_exp(s, ch, fixed_exp);
204 for(ch = 0; ch < s->nb_channels; ch++) {
205 if (s->channel_coded[ch]) {
207 float *coefs, *exponents, mult;
210 coefs1 = s->coefs1[ch];
211 exponents = s->exponents[ch];
212 mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
214 coefs = src_coefs[ch];
215 if (s->use_noise_coding && 0) {
216 assert(0); //FIXME not implemented
218 coefs += s->coefs_start;
220 for(i = 0;i < n; i++){
221 double t= *coefs++ / (exponents[i] * mult);
222 if(t<-32768 || t>32767)
225 coefs1[i] = lrint(t);
232 for(ch = 0; ch < s->nb_channels; ch++) {
233 int a = s->channel_coded[ch];
234 put_bits(&s->pb, 1, a);
241 for(v= total_gain-1; v>=127; v-= 127)
242 put_bits(&s->pb, 7, 127);
243 put_bits(&s->pb, 7, v);
245 coef_nb_bits= ff_wma_total_gain_to_bits(total_gain);
247 if (s->use_noise_coding) {
248 for(ch = 0; ch < s->nb_channels; ch++) {
249 if (s->channel_coded[ch]) {
251 n = s->exponent_high_sizes[bsize];
253 put_bits(&s->pb, 1, s->high_band_coded[ch][i]= 0);
255 nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
262 if (s->block_len_bits != s->frame_len_bits) {
263 put_bits(&s->pb, 1, parse_exponents);
266 if (parse_exponents) {
267 for(ch = 0; ch < s->nb_channels; ch++) {
268 if (s->channel_coded[ch]) {
269 if (s->use_exp_vlc) {
270 encode_exp_vlc(s, ch, fixed_exp);
272 assert(0); //FIXME not implemented
273 // encode_exp_lsp(s, ch);
278 assert(0); //FIXME not implemented
281 for(ch = 0; ch < s->nb_channels; ch++) {
282 if (s->channel_coded[ch]) {
285 tindex = (ch == 1 && s->ms_stereo);
286 ptr = &s->coefs1[ch][0];
287 eptr = ptr + nb_coefs[ch];
290 for(;ptr < eptr; ptr++){
293 int abs_level= FFABS(level);
295 if(abs_level <= s->coef_vlcs[tindex]->max_level){
296 if(run < s->coef_vlcs[tindex]->levels[abs_level-1])
297 code= run + s->int_table[tindex][abs_level-1];
300 assert(code < s->coef_vlcs[tindex]->n);
301 put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[code], s->coef_vlcs[tindex]->huffcodes[code]);
304 if(1<<coef_nb_bits <= abs_level)
308 //Workaround minor rounding differences for the regression tests, FIXME we should find and replace the problematic float by fixpoint for reg tests
309 if(abs_level == 0x71B && (s->avctx->flags & CODEC_FLAG_BITEXACT)) abs_level=0x71A;
311 put_bits(&s->pb, coef_nb_bits, abs_level);
312 put_bits(&s->pb, s->frame_len_bits, run);
314 put_bits(&s->pb, 1, level < 0); //FIXME the sign is fliped somewhere
321 put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[1], s->coef_vlcs[tindex]->huffcodes[1]);
323 if (s->version == 1 && s->nb_channels >= 2) {
324 avpriv_align_put_bits(&s->pb);
330 static int encode_frame(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], uint8_t *buf, int buf_size, int total_gain){
331 init_put_bits(&s->pb, buf, buf_size);
333 if (s->use_bit_reservoir) {
334 assert(0);//FIXME not implemented
336 if(encode_block(s, src_coefs, total_gain) < 0)
340 avpriv_align_put_bits(&s->pb);
342 return put_bits_count(&s->pb)/8 - s->block_align;
345 static int encode_superframe(AVCodecContext *avctx,
346 unsigned char *buf, int buf_size, void *data){
347 WMACodecContext *s = avctx->priv_data;
348 const short *samples = data;
351 s->block_len_bits= s->frame_len_bits; //required by non variable block len
352 s->block_len = 1 << s->block_len_bits;
354 apply_window_and_mdct(avctx, samples, avctx->frame_size);
360 for(i = 0; i < s->block_len; i++) {
361 a = s->coefs[0][i]*0.5;
362 b = s->coefs[1][i]*0.5;
363 s->coefs[0][i] = a + b;
364 s->coefs[1][i] = a - b;
368 if (buf_size < 2 * MAX_CODED_SUPERFRAME_SIZE) {
369 av_log(avctx, AV_LOG_ERROR, "output buffer size is too small\n");
370 return AVERROR(EINVAL);
376 int error= encode_frame(s, s->coefs, buf, buf_size, total_gain-i);
382 best= encode_frame(s, s->coefs, buf, buf_size, total_gain);
384 int scoreL= encode_frame(s, s->coefs, buf, buf_size, total_gain-i);
385 int scoreR= encode_frame(s, s->coefs, buf, buf_size, total_gain+i);
386 av_log(NULL, AV_LOG_ERROR, "%d %d %d (%d)\n", scoreL, best, scoreR, total_gain);
387 if(scoreL < FFMIN(best, scoreR)){
390 }else if(scoreR < best){
397 if ((i = encode_frame(s, s->coefs, buf, buf_size, total_gain)) >= 0) {
398 av_log(avctx, AV_LOG_ERROR, "required frame size too large. please "
399 "use a higher bit rate.\n");
400 return AVERROR(EINVAL);
402 assert((put_bits_count(&s->pb) & 7) == 0);
404 put_bits(&s->pb, 8, 'N');
406 flush_put_bits(&s->pb);
407 return s->block_align;
410 AVCodec ff_wmav1_encoder = {
412 .type = AVMEDIA_TYPE_AUDIO,
413 .id = CODEC_ID_WMAV1,
414 .priv_data_size = sizeof(WMACodecContext),
416 .encode = encode_superframe,
418 .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE},
419 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"),
422 AVCodec ff_wmav2_encoder = {
424 .type = AVMEDIA_TYPE_AUDIO,
425 .id = CODEC_ID_WMAV2,
426 .priv_data_size = sizeof(WMACodecContext),
428 .encode = encode_superframe,
430 .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE},
431 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"),