yading@10: /* yading@10: * audio encoder psychoacoustic model yading@10: * Copyright (C) 2008 Konstantin Shishkov yading@10: * yading@10: * This file is part of FFmpeg. yading@10: * yading@10: * FFmpeg is free software; you can redistribute it and/or yading@10: * modify it under the terms of the GNU Lesser General Public yading@10: * License as published by the Free Software Foundation; either yading@10: * version 2.1 of the License, or (at your option) any later version. yading@10: * yading@10: * FFmpeg is distributed in the hope that it will be useful, yading@10: * but WITHOUT ANY WARRANTY; without even the implied warranty of yading@10: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU yading@10: * Lesser General Public License for more details. yading@10: * yading@10: * You should have received a copy of the GNU Lesser General Public yading@10: * License along with FFmpeg; if not, write to the Free Software yading@10: * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA yading@10: */ yading@10: yading@10: #include yading@10: yading@10: #include "avcodec.h" yading@10: #include "psymodel.h" yading@10: #include "iirfilter.h" yading@10: #include "libavutil/mem.h" yading@10: yading@10: extern const FFPsyModel ff_aac_psy_model; yading@10: yading@10: av_cold int ff_psy_init(FFPsyContext *ctx, AVCodecContext *avctx, int num_lens, yading@10: const uint8_t **bands, const int* num_bands, yading@10: int num_groups, const uint8_t *group_map) yading@10: { yading@10: int i, j, k = 0; yading@10: yading@10: ctx->avctx = avctx; yading@10: ctx->ch = av_mallocz(sizeof(ctx->ch[0]) * avctx->channels * 2); yading@10: ctx->group = av_mallocz(sizeof(ctx->group[0]) * num_groups); yading@10: ctx->bands = av_malloc (sizeof(ctx->bands[0]) * num_lens); yading@10: ctx->num_bands = av_malloc (sizeof(ctx->num_bands[0]) * num_lens); yading@10: memcpy(ctx->bands, bands, sizeof(ctx->bands[0]) * num_lens); yading@10: memcpy(ctx->num_bands, num_bands, sizeof(ctx->num_bands[0]) * num_lens); yading@10: yading@10: /* assign channels to groups (with virtual channels for coupling) */ yading@10: for (i = 0; i < num_groups; i++) { yading@10: /* NOTE: Add 1 to handle the AAC chan_config without modification. yading@10: * This has the side effect of allowing an array of 0s to map yading@10: * to one channel per group. yading@10: */ yading@10: ctx->group[i].num_ch = group_map[i] + 1; yading@10: for (j = 0; j < ctx->group[i].num_ch * 2; j++) yading@10: ctx->group[i].ch[j] = &ctx->ch[k++]; yading@10: } yading@10: yading@10: switch (ctx->avctx->codec_id) { yading@10: case AV_CODEC_ID_AAC: yading@10: ctx->model = &ff_aac_psy_model; yading@10: break; yading@10: } yading@10: if (ctx->model->init) yading@10: return ctx->model->init(ctx); yading@10: return 0; yading@10: } yading@10: yading@10: FFPsyChannelGroup *ff_psy_find_group(FFPsyContext *ctx, int channel) yading@10: { yading@10: int i = 0, ch = 0; yading@10: yading@10: while (ch <= channel) yading@10: ch += ctx->group[i++].num_ch; yading@10: yading@10: return &ctx->group[i-1]; yading@10: } yading@10: yading@10: av_cold void ff_psy_end(FFPsyContext *ctx) yading@10: { yading@10: if (ctx->model->end) yading@10: ctx->model->end(ctx); yading@10: av_freep(&ctx->bands); yading@10: av_freep(&ctx->num_bands); yading@10: av_freep(&ctx->group); yading@10: av_freep(&ctx->ch); yading@10: } yading@10: yading@10: typedef struct FFPsyPreprocessContext{ yading@10: AVCodecContext *avctx; yading@10: float stereo_att; yading@10: struct FFIIRFilterCoeffs *fcoeffs; yading@10: struct FFIIRFilterState **fstate; yading@10: struct FFIIRFilterContext fiir; yading@10: }FFPsyPreprocessContext; yading@10: yading@10: #define FILT_ORDER 4 yading@10: yading@10: av_cold struct FFPsyPreprocessContext* ff_psy_preprocess_init(AVCodecContext *avctx) yading@10: { yading@10: FFPsyPreprocessContext *ctx; yading@10: int i; yading@10: float cutoff_coeff = 0; yading@10: ctx = av_mallocz(sizeof(FFPsyPreprocessContext)); yading@10: ctx->avctx = avctx; yading@10: yading@10: if (avctx->cutoff > 0) yading@10: cutoff_coeff = 2.0 * avctx->cutoff / avctx->sample_rate; yading@10: yading@10: if (!cutoff_coeff && avctx->codec_id == AV_CODEC_ID_AAC) yading@10: cutoff_coeff = 2.0 * AAC_CUTOFF(avctx) / avctx->sample_rate; yading@10: yading@10: if (cutoff_coeff && cutoff_coeff < 0.98) yading@10: ctx->fcoeffs = ff_iir_filter_init_coeffs(avctx, FF_FILTER_TYPE_BUTTERWORTH, yading@10: FF_FILTER_MODE_LOWPASS, FILT_ORDER, yading@10: cutoff_coeff, 0.0, 0.0); yading@10: if (ctx->fcoeffs) { yading@10: ctx->fstate = av_mallocz(sizeof(ctx->fstate[0]) * avctx->channels); yading@10: for (i = 0; i < avctx->channels; i++) yading@10: ctx->fstate[i] = ff_iir_filter_init_state(FILT_ORDER); yading@10: } yading@10: yading@10: ff_iir_filter_init(&ctx->fiir); yading@10: yading@10: return ctx; yading@10: } yading@10: yading@10: void ff_psy_preprocess(struct FFPsyPreprocessContext *ctx, float **audio, int channels) yading@10: { yading@10: int ch; yading@10: int frame_size = ctx->avctx->frame_size; yading@10: FFIIRFilterContext *iir = &ctx->fiir; yading@10: yading@10: if (ctx->fstate) { yading@10: for (ch = 0; ch < channels; ch++) yading@10: iir->filter_flt(ctx->fcoeffs, ctx->fstate[ch], frame_size, yading@10: &audio[ch][frame_size], 1, &audio[ch][frame_size], 1); yading@10: } yading@10: } yading@10: yading@10: av_cold void ff_psy_preprocess_end(struct FFPsyPreprocessContext *ctx) yading@10: { yading@10: int i; yading@10: ff_iir_filter_free_coeffs(ctx->fcoeffs); yading@10: if (ctx->fstate) yading@10: for (i = 0; i < ctx->avctx->channels; i++) yading@10: ff_iir_filter_free_state(ctx->fstate[i]); yading@10: av_freep(&ctx->fstate); yading@10: av_free(ctx); yading@10: }