/* * WMA compatible encoder * Copyright (c) 2007 Michael Niedermayer * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "avcodec.h" #include "wma.h" #undef NDEBUG #include <assert.h> static int encode_init(AVCodecContext * avctx){ WMACodecContext *s = avctx->priv_data; int i, flags1, flags2; uint8_t *extradata; s->avctx = avctx; if(avctx->channels > MAX_CHANNELS) return -1; if(avctx->bit_rate < 24*1000) return -1; /* extract flag infos */ flags1 = 0; flags2 = 1; if (avctx->codec->id == CODEC_ID_WMAV1) { extradata= av_malloc(4); avctx->extradata_size= 4; AV_WL16(extradata, flags1); AV_WL16(extradata+2, flags2); } else if (avctx->codec->id == CODEC_ID_WMAV2) { extradata= av_mallocz(10); avctx->extradata_size= 10; AV_WL32(extradata, flags1); AV_WL16(extradata+4, flags2); }else assert(0); avctx->extradata= extradata; s->use_exp_vlc = flags2 & 0x0001; s->use_bit_reservoir = flags2 & 0x0002; s->use_variable_block_len = flags2 & 0x0004; ff_wma_init(avctx, flags2); /* init MDCT */ for(i = 0; i < s->nb_block_sizes; i++) ff_mdct_init(&s->mdct_ctx[i], s->frame_len_bits - i + 1, 0); avctx->block_align= s->block_align= avctx->bit_rate*(int64_t)s->frame_len / (avctx->sample_rate*8); //av_log(NULL, AV_LOG_ERROR, "%d %d %d %d\n", s->block_align, avctx->bit_rate, s->frame_len, avctx->sample_rate); avctx->frame_size= s->frame_len; return 0; } static void apply_window_and_mdct(AVCodecContext * avctx, signed short * audio, int len) { WMACodecContext *s = avctx->priv_data; int window_index= s->frame_len_bits - s->block_len_bits; int i, j, channel; const float * win = s->windows[window_index]; int window_len = 1 << s->block_len_bits; float n = window_len/2; for (channel = 0; channel < avctx->channels; channel++) { memcpy(s->output, s->frame_out[channel], sizeof(float)*window_len); j = channel; for (i = 0; i < len; i++, j += avctx->channels){ s->output[i+window_len] = audio[j] / n * win[window_len - i - 1]; s->frame_out[channel][i] = audio[j] / n * win[i]; } ff_mdct_calc(&s->mdct_ctx[window_index], s->coefs[channel], s->output, s->mdct_tmp); } } //FIXME use for decoding too static void init_exp(WMACodecContext *s, int ch, const int *exp_param){ int n; const uint16_t *ptr; float v, *q, max_scale, *q_end; ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits]; q = s->exponents[ch]; q_end = q + s->block_len; max_scale = 0; while (q < q_end) { /* XXX: use a table */ v = pow(10, *exp_param++ * (1.0 / 16.0)); max_scale= FFMAX(max_scale, v); n = *ptr++; do { *q++ = v; } while (--n); } s->max_exponent[ch] = max_scale; } static void encode_exp_vlc(WMACodecContext *s, int ch, const int *exp_param){ int last_exp; const uint16_t *ptr; float *q, *q_end; ptr = s->exponent_bands[s->frame_len_bits - s->block_len_bits]; q = s->exponents[ch]; q_end = q + s->block_len; if (s->version == 1) { last_exp= *exp_param++; assert(last_exp-10 >= 0 && last_exp-10 < 32); put_bits(&s->pb, 5, last_exp - 10); q+= *ptr++; }else last_exp = 36; while (q < q_end) { int exp = *exp_param++; int code = exp - last_exp + 60; assert(code >= 0 && code < 120); put_bits(&s->pb, ff_wma_scale_huffbits[code], ff_wma_scale_huffcodes[code]); /* XXX: use a table */ q+= *ptr++; last_exp= exp; } } static int encode_block(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], int total_gain){ int v, bsize, ch, coef_nb_bits, parse_exponents; float mdct_norm; int nb_coefs[MAX_CHANNELS]; 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}; //FIXME remove duplication relative to decoder if (s->use_variable_block_len) { assert(0); //FIXME not implemented }else{ /* fixed block len */ s->next_block_len_bits = s->frame_len_bits; s->prev_block_len_bits = s->frame_len_bits; s->block_len_bits = s->frame_len_bits; } s->block_len = 1 << s->block_len_bits; // assert((s->block_pos + s->block_len) <= s->frame_len); bsize = s->frame_len_bits - s->block_len_bits; //FIXME factor v = s->coefs_end[bsize] - s->coefs_start; for(ch = 0; ch < s->nb_channels; ch++) nb_coefs[ch] = v; { int n4 = s->block_len / 2; mdct_norm = 1.0 / (float)n4; if (s->version == 1) { mdct_norm *= sqrt(n4); } } if (s->nb_channels == 2) { put_bits(&s->pb, 1, s->ms_stereo= 1); } for(ch = 0; ch < s->nb_channels; ch++) { if ((s->channel_coded[ch]= 1)) { //FIXME only set channel_coded when needed, instead of always init_exp(s, ch, fixed_exp); } } for(ch = 0; ch < s->nb_channels; ch++) { if (s->channel_coded[ch]) { int16_t *coefs1; float *coefs, *exponents, mult; int i, n; coefs1 = s->coefs1[ch]; exponents = s->exponents[ch]; mult = pow(10, total_gain * 0.05) / s->max_exponent[ch]; mult *= mdct_norm; coefs = src_coefs[ch]; if (s->use_noise_coding && 0) { assert(0); //FIXME not implemented } else { coefs += s->coefs_start; n = nb_coefs[ch]; for(i = 0;i < n; i++){ double t= *coefs++ / (exponents[i] * mult); if(t<-32768 || t>32767) return -1; coefs1[i] = lrint(t); } } } } v = 0; for(ch = 0; ch < s->nb_channels; ch++) { int a = s->channel_coded[ch]; put_bits(&s->pb, 1, a); v |= a; } if (!v) return 1; for(v= total_gain-1; v>=127; v-= 127) put_bits(&s->pb, 7, 127); put_bits(&s->pb, 7, v); coef_nb_bits= ff_wma_total_gain_to_bits(total_gain); if (s->use_noise_coding) { for(ch = 0; ch < s->nb_channels; ch++) { if (s->channel_coded[ch]) { int i, n; n = s->exponent_high_sizes[bsize]; for(i=0;i<n;i++) { put_bits(&s->pb, 1, s->high_band_coded[ch][i]= 0); if (0) nb_coefs[ch] -= s->exponent_high_bands[bsize][i]; } } } } parse_exponents = 1; if (s->block_len_bits != s->frame_len_bits) { put_bits(&s->pb, 1, parse_exponents); } if (parse_exponents) { for(ch = 0; ch < s->nb_channels; ch++) { if (s->channel_coded[ch]) { if (s->use_exp_vlc) { encode_exp_vlc(s, ch, fixed_exp); } else { assert(0); //FIXME not implemented // encode_exp_lsp(s, ch); } } } } else { assert(0); //FIXME not implemented } for(ch = 0; ch < s->nb_channels; ch++) { if (s->channel_coded[ch]) { int run, tindex; int16_t *ptr, *eptr; tindex = (ch == 1 && s->ms_stereo); ptr = &s->coefs1[ch][0]; eptr = ptr + nb_coefs[ch]; run=0; for(;ptr < eptr; ptr++){ if(*ptr){ int level= *ptr; int abs_level= FFABS(level); int code= 0; if(abs_level <= s->coef_vlcs[tindex]->max_level){ if(run < s->coef_vlcs[tindex]->levels[abs_level-1]) code= run + s->int_table[tindex][abs_level-1]; } assert(code < s->coef_vlcs[tindex]->n); put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[code], s->coef_vlcs[tindex]->huffcodes[code]); if(code == 0){ if(1<<coef_nb_bits <= abs_level) return -1; put_bits(&s->pb, coef_nb_bits, abs_level); put_bits(&s->pb, s->frame_len_bits, run); } put_bits(&s->pb, 1, level < 0); //FIXME the sign is fliped somewhere run=0; }else{ run++; } } if(run) put_bits(&s->pb, s->coef_vlcs[tindex]->huffbits[1], s->coef_vlcs[tindex]->huffcodes[1]); } if (s->version == 1 && s->nb_channels >= 2) { align_put_bits(&s->pb); } } return 0; } static int encode_frame(WMACodecContext *s, float (*src_coefs)[BLOCK_MAX_SIZE], uint8_t *buf, int buf_size, int total_gain){ init_put_bits(&s->pb, buf, buf_size); if (s->use_bit_reservoir) { assert(0);//FIXME not implemented }else{ if(encode_block(s, src_coefs, total_gain) < 0) return INT_MAX; } align_put_bits(&s->pb); return put_bits_count(&s->pb)/8 - s->block_align; } static int encode_superframe(AVCodecContext *avctx, unsigned char *buf, int buf_size, void *data){ WMACodecContext *s = avctx->priv_data; short *samples = data; int i, total_gain; s->block_len_bits= s->frame_len_bits; //required by non variable block len s->block_len = 1 << s->block_len_bits; apply_window_and_mdct(avctx, samples, avctx->frame_size); if (s->ms_stereo) { float a, b; int i; for(i = 0; i < s->block_len; i++) { a = s->coefs[0][i]*0.5; b = s->coefs[1][i]*0.5; s->coefs[0][i] = a + b; s->coefs[1][i] = a - b; } } #if 1 total_gain= 128; for(i=64; i; i>>=1){ int error= encode_frame(s, s->coefs, buf, buf_size, total_gain-i); if(error<0) total_gain-= i; } #else total_gain= 90; best= encode_frame(s, s->coefs, buf, buf_size, total_gain); for(i=32; i; i>>=1){ int scoreL= encode_frame(s, s->coefs, buf, buf_size, total_gain-i); int scoreR= encode_frame(s, s->coefs, buf, buf_size, total_gain+i); av_log(NULL, AV_LOG_ERROR, "%d %d %d (%d)\n", scoreL, best, scoreR, total_gain); if(scoreL < FFMIN(best, scoreR)){ best = scoreL; total_gain -= i; }else if(scoreR < best){ best = scoreR; total_gain += i; } } #endif encode_frame(s, s->coefs, buf, buf_size, total_gain); assert((put_bits_count(&s->pb) & 7) == 0); i= s->block_align - (put_bits_count(&s->pb)+7)/8; assert(i>=0); while(i--) put_bits(&s->pb, 8, 'N'); flush_put_bits(&s->pb); return pbBufPtr(&s->pb) - s->pb.buf; } AVCodec wmav1_encoder = { "wmav1", CODEC_TYPE_AUDIO, CODEC_ID_WMAV1, sizeof(WMACodecContext), encode_init, encode_superframe, ff_wma_end, .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 1"), }; AVCodec wmav2_encoder = { "wmav2", CODEC_TYPE_AUDIO, CODEC_ID_WMAV2, sizeof(WMACodecContext), encode_init, encode_superframe, ff_wma_end, .long_name = NULL_IF_CONFIG_SMALL("Windows Media Audio 2"), };