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
30 static int encode_init(AVCodecContext * avctx){
31 WMACodecContext *s = avctx->priv_data;
32 int i, flags1, flags2;
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);
43 if (avctx->sample_rate > 48000) {
44 av_log(avctx, AV_LOG_ERROR, "sample rate is too high: %d > 48kHz",
46 return AVERROR(EINVAL);
49 if(avctx->bit_rate < 24*1000) {
50 av_log(avctx, AV_LOG_ERROR, "bitrate too low: got %i, need 24000 or higher\n",
52 return AVERROR(EINVAL);
55 /* extract flag infos */
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);
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)
77 ff_wma_init(avctx, flags2);
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);
83 s->block_align = avctx->bit_rate * (int64_t)s->frame_len /
84 (avctx->sample_rate * 8);
85 s->block_align = FFMIN(s->block_align, MAX_CODED_SUPERFRAME_SIZE);
86 avctx->block_align = s->block_align;
87 avctx->bit_rate = avctx->block_align * 8LL * avctx->sample_rate /
89 avctx->frame_size = avctx->delay = s->frame_len;
91 #if FF_API_OLD_ENCODE_AUDIO
92 avctx->coded_frame = &s->frame;
93 avcodec_get_frame_defaults(avctx->coded_frame);
100 static void apply_window_and_mdct(AVCodecContext * avctx, const signed short * audio, int len) {
101 WMACodecContext *s = avctx->priv_data;
102 int window_index= s->frame_len_bits - s->block_len_bits;
103 FFTContext *mdct = &s->mdct_ctx[window_index];
105 const float * win = s->windows[window_index];
106 int window_len = 1 << s->block_len_bits;
107 float n = window_len/2;
109 for (channel = 0; channel < avctx->channels; channel++) {
110 memcpy(s->output, s->frame_out[channel], sizeof(float)*window_len);
112 for (i = 0; i < len; i++, j += avctx->channels){
113 s->output[i+window_len] = audio[j] / n * win[window_len - i - 1];
114 s->frame_out[channel][i] = audio[j] / n * win[i];
116 mdct->mdct_calc(mdct, s->coefs[channel], s->output);
120 //FIXME use for decoding too
121 static void init_exp(WMACodecContext *s, int ch, const int *exp_param){
124 float v, *q, max_scale, *q_end;
126 ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
127 q = s->exponents[ch];
128 q_end = q + s->block_len;
131 /* XXX: use a table */
132 v = pow(10, *exp_param++ * (1.0 / 16.0));
133 max_scale= FFMAX(max_scale, v);
139 s->max_exponent[ch] = max_scale;
142 static void encode_exp_vlc(WMACodecContext *s, int ch, const int *exp_param){
147 ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits];
148 q = s->exponents[ch];
149 q_end = q + s->block_len;
150 if (s->version == 1) {
151 last_exp= *exp_param++;
152 assert(last_exp-10 >= 0 && last_exp-10 < 32);
153 put_bits(&s->pb, 5, last_exp - 10);
158 int exp = *exp_param++;
159 int code = exp - last_exp + 60;
160 assert(code >= 0 && code < 120);
161 put_bits(&s->pb, ff_aac_scalefactor_bits[code], ff_aac_scalefactor_code[code]);
162 /* XXX: use a table */
168 static int encode_block(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], int total_gain){
169 int v, bsize, ch, coef_nb_bits, parse_exponents;
171 int nb_coefs[MAX_CHANNELS];
172 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 //FIXME remove duplication relative to decoder
175 if (s->use_variable_block_len) {
176 assert(0); //FIXME not implemented
178 /* fixed block len */
179 s->next_block_len_bits = s->frame_len_bits;
180 s->prev_block_len_bits = s->frame_len_bits;
181 s->block_len_bits = s->frame_len_bits;
184 s->block_len = 1 << s->block_len_bits;
185 // assert((s->block_pos + s->block_len) <= s->frame_len);
186 bsize = s->frame_len_bits - s->block_len_bits;
189 v = s->coefs_end[bsize] - s->coefs_start;
190 for(ch = 0; ch < s->nb_channels; ch++)
193 int n4 = s->block_len / 2;
194 mdct_norm = 1.0 / (float)n4;
195 if (s->version == 1) {
196 mdct_norm *= sqrt(n4);
200 if (s->nb_channels == 2) {
201 put_bits(&s->pb, 1, !!s->ms_stereo);
204 for(ch = 0; ch < s->nb_channels; ch++) {
205 s->channel_coded[ch] = 1; //FIXME only set channel_coded when needed, instead of always
206 if (s->channel_coded[ch]) {
207 init_exp(s, ch, fixed_exp);
211 for(ch = 0; ch < s->nb_channels; ch++) {
212 if (s->channel_coded[ch]) {
214 float *coefs, *exponents, mult;
217 coefs1 = s->coefs1[ch];
218 exponents = s->exponents[ch];
219 mult = pow(10, total_gain * 0.05) / s->max_exponent[ch];
221 coefs = src_coefs[ch];
222 if (s->use_noise_coding && 0) {
223 assert(0); //FIXME not implemented
225 coefs += s->coefs_start;
227 for(i = 0;i < n; i++){
228 double t= *coefs++ / (exponents[i] * mult);
229 if(t<-32768 || t>32767)
232 coefs1[i] = lrint(t);
239 for(ch = 0; ch < s->nb_channels; ch++) {
240 int a = s->channel_coded[ch];
241 put_bits(&s->pb, 1, a);
248 for(v= total_gain-1; v>=127; v-= 127)
249 put_bits(&s->pb, 7, 127);
250 put_bits(&s->pb, 7, v);
252 coef_nb_bits= ff_wma_total_gain_to_bits(total_gain);
254 if (s->use_noise_coding) {
255 for(ch = 0; ch < s->nb_channels; ch++) {
256 if (s->channel_coded[ch]) {
258 n = s->exponent_high_sizes[bsize];
260 put_bits(&s->pb, 1, s->high_band_coded[ch][i]= 0);
262 nb_coefs[ch] -= s->exponent_high_bands[bsize][i];
269 if (s->block_len_bits != s->frame_len_bits) {
270 put_bits(&s->pb, 1, parse_exponents);
273 if (parse_exponents) {
274 for(ch = 0; ch < s->nb_channels; ch++) {
275 if (s->channel_coded[ch]) {
276 if (s->use_exp_vlc) {
277 encode_exp_vlc(s, ch, fixed_exp);
279 assert(0); //FIXME not implemented
280 // encode_exp_lsp(s, ch);
285 assert(0); //FIXME not implemented
288 for(ch = 0; ch < s->nb_channels; ch++) {
289 if (s->channel_coded[ch]) {
292 tindex = (ch == 1 && s->ms_stereo);
293 ptr = &s->coefs1[ch][0];
294 eptr = ptr + nb_coefs[ch];
297 for(;ptr < eptr; ptr++){
300 int abs_level= FFABS(level);
302 if(abs_level <= s->coef_vlcs[tindex]->max_level){
303 if(run < s->coef_vlcs[tindex]->levels[abs_level-1])
304 code= run + s->int_table[tindex][abs_level-1];
307 assert(code < s->coef_vlcs[tindex]->n);
308 put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[code], s->coef_vlcs[tindex]->huffcodes[code]);
311 if(1<<coef_nb_bits <= abs_level)
314 put_bits(&s->pb, coef_nb_bits, abs_level);
315 put_bits(&s->pb, s->frame_len_bits, run);
317 put_bits(&s->pb, 1, level < 0); //FIXME the sign is fliped somewhere
324 put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[1], s->coef_vlcs[tindex]->huffcodes[1]);
326 if (s->version == 1 && s->nb_channels >= 2) {
327 avpriv_align_put_bits(&s->pb);
333 static int encode_frame(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], uint8_t *buf, int buf_size, int total_gain){
334 init_put_bits(&s->pb, buf, buf_size);
336 if (s->use_bit_reservoir) {
337 assert(0);//FIXME not implemented
339 if(encode_block(s, src_coefs, total_gain) < 0)
343 avpriv_align_put_bits(&s->pb);
345 return put_bits_count(&s->pb)/8 - s->block_align;
348 static int encode_superframe(AVCodecContext *avctx, AVPacket *avpkt,
349 const AVFrame *frame, int *got_packet_ptr)
351 WMACodecContext *s = avctx->priv_data;
352 const int16_t *samples = (const int16_t *)frame->data[0];
353 int i, total_gain, ret;
355 s->block_len_bits= s->frame_len_bits; //required by non variable block len
356 s->block_len = 1 << s->block_len_bits;
358 apply_window_and_mdct(avctx, samples, frame->nb_samples);
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;
372 if ((ret = ff_alloc_packet(avpkt, 2 * MAX_CODED_SUPERFRAME_SIZE))) {
373 av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
380 int error = encode_frame(s, s->coefs, avpkt->data, avpkt->size,
387 best = encode_frame(s, s->coefs, avpkt->data, avpkt->size, total_gain);
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)){
395 }else if(scoreR < best){
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);
407 assert((put_bits_count(&s->pb) & 7) == 0);
409 put_bits(&s->pb, 8, 'N');
411 flush_put_bits(&s->pb);
413 if (frame->pts != AV_NOPTS_VALUE)
414 avpkt->pts = frame->pts - ff_samples_to_time_base(avctx, avctx->delay);
416 avpkt->size = s->block_align;
421 AVCodec ff_wmav1_encoder = {
423 .type = AVMEDIA_TYPE_AUDIO,
424 .id = AV_CODEC_ID_WMAV1,
425 .priv_data_size = sizeof(WMACodecContext),
427 .encode2 = encode_superframe,
429 .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
430 AV_SAMPLE_FMT_NONE },
431 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"),
434 AVCodec ff_wmav2_encoder = {
436 .type = AVMEDIA_TYPE_AUDIO,
437 .id = AV_CODEC_ID_WMAV2,
438 .priv_data_size = sizeof(WMACodecContext),
440 .encode2 = encode_superframe,
442 .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
443 AV_SAMPLE_FMT_NONE },
444 .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"),