From 1914e6f010b3320025c7b692aaea51d9b9a992a8 Mon Sep 17 00:00:00 2001 From: Alex Converse Date: Mon, 16 Sep 2013 13:03:15 -0700 Subject: aacdec: Add support for LD (Low Delay) AAC --- libavcodec/aacdec.c | 67 +++++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 63 insertions(+), 4 deletions(-) (limited to 'libavcodec/aacdec.c') diff --git a/libavcodec/aacdec.c b/libavcodec/aacdec.c index a7c4151e82..35efb8c689 100644 --- a/libavcodec/aacdec.c +++ b/libavcodec/aacdec.c @@ -817,6 +817,13 @@ static int decode_audio_specific_config(AACContext *ac, m4ac->sampling_index); return AVERROR_INVALIDDATA; } + if (m4ac->object_type == AOT_ER_AAC_LD && + (m4ac->sampling_index < 3 || m4ac->sampling_index > 7)) { + av_log(avctx, AV_LOG_ERROR, + "invalid low delay sampling rate index %d\n", + m4ac->sampling_index); + return AVERROR_INVALIDDATA; + } skip_bits_long(&gb, i); @@ -825,6 +832,7 @@ static int decode_audio_specific_config(AACContext *ac, case AOT_AAC_LC: case AOT_AAC_LTP: case AOT_ER_AAC_LC: + case AOT_ER_AAC_LD: if ((ret = decode_ga_specific_config(ac, avctx, &gb, m4ac, m4ac->chan_config)) < 0) return ret; @@ -985,12 +993,15 @@ static av_cold int aac_decode_init(AVCodecContext *avctx) 352); ff_mdct_init(&ac->mdct, 11, 1, 1.0 / (32768.0 * 1024.0)); + ff_mdct_init(&ac->mdct_ld, 10, 1, 1.0 / (32768.0 * 512.0)); ff_mdct_init(&ac->mdct_small, 8, 1, 1.0 / (32768.0 * 128.0)); ff_mdct_init(&ac->mdct_ltp, 11, 0, -2.0 * 32768.0); // window initialization ff_kbd_window_init(ff_aac_kbd_long_1024, 4.0, 1024); + ff_kbd_window_init(ff_aac_kbd_long_512, 4.0, 512); ff_kbd_window_init(ff_aac_kbd_short_128, 6.0, 128); ff_init_ff_sine_windows(10); + ff_init_ff_sine_windows( 9); ff_init_ff_sine_windows( 7); cbrt_tableinit(); @@ -1063,6 +1074,14 @@ static int decode_ics_info(AACContext *ac, IndividualChannelStream *ics, } ics->window_sequence[1] = ics->window_sequence[0]; ics->window_sequence[0] = get_bits(gb, 2); + if (ac->oc[1].m4ac.object_type == AOT_ER_AAC_LD && + ics->window_sequence[0] != ONLY_LONG_SEQUENCE) { + av_log(ac->avctx, AV_LOG_ERROR, + "AAC LD is only defined for ONLY_LONG_SEQUENCE but " + "window sequence %d found.\n", ics->window_sequence[0]); + ics->window_sequence[0] = ONLY_LONG_SEQUENCE; + return AVERROR_INVALIDDATA; + } ics->use_kb_window[1] = ics->use_kb_window[0]; ics->use_kb_window[0] = get_bits1(gb); ics->num_window_groups = 1; @@ -1086,8 +1105,15 @@ static int decode_ics_info(AACContext *ac, IndividualChannelStream *ics, } else { ics->max_sfb = get_bits(gb, 6); ics->num_windows = 1; - ics->swb_offset = ff_swb_offset_1024[ac->oc[1].m4ac.sampling_index]; - ics->num_swb = ff_aac_num_swb_1024[ac->oc[1].m4ac.sampling_index]; + if (ac->oc[1].m4ac.object_type == AOT_ER_AAC_LD) { + ics->swb_offset = ff_swb_offset_512[ac->oc[1].m4ac.sampling_index]; + ics->num_swb = ff_aac_num_swb_512[ac->oc[1].m4ac.sampling_index]; + if (!ics->num_swb || !ics->swb_offset) + return AVERROR_BUG; + } else { + ics->swb_offset = ff_swb_offset_1024[ac->oc[1].m4ac.sampling_index]; + ics->num_swb = ff_aac_num_swb_1024[ac->oc[1].m4ac.sampling_index]; + } ics->tns_max_bands = ff_tns_max_bands_1024[ac->oc[1].m4ac.sampling_index]; ics->predictor_present = get_bits1(gb); ics->predictor_reset_group = 0; @@ -1102,6 +1128,11 @@ static int decode_ics_info(AACContext *ac, IndividualChannelStream *ics, "Prediction is not allowed in AAC-LC.\n"); return AVERROR_INVALIDDATA; } else { + if (ac->oc[1].m4ac.object_type == AOT_ER_AAC_LD) { + av_log(ac->avctx, AV_LOG_ERROR, + "LTP in ER AAC LD not yet implemented.\n"); + return AVERROR_PATCHWELCOME; + } if ((ics->ltp.present = get_bits(gb, 1))) decode_ltp(&ics->ltp, gb, ics->max_sfb); } @@ -2314,6 +2345,25 @@ static void imdct_and_windowing(AACContext *ac, SingleChannelElement *sce) } } +static void imdct_and_windowing_ld(AACContext *ac, SingleChannelElement *sce) +{ + IndividualChannelStream *ics = &sce->ics; + float *in = sce->coeffs; + float *out = sce->ret; + float *saved = sce->saved; + const float *lwindow_prev = ics->use_kb_window[1] ? ff_aac_kbd_long_512 : ff_sine_512; + float *buf = ac->buf_mdct; + + // imdct + ac->mdct.imdct_half(&ac->mdct_ld, buf, in); + + // window overlapping + ac->fdsp.vector_fmul_window(out, saved, buf, lwindow_prev, 256); + + // buffer update + memcpy(saved, buf + 256, 256 * sizeof(float)); +} + /** * Apply dependent channel coupling (applied before IMDCT). * @@ -2410,6 +2460,11 @@ static void apply_channel_coupling(AACContext *ac, ChannelElement *cc, static void spectral_to_sample(AACContext *ac) { int i, type; + void (*imdct_and_window)(AACContext *ac, SingleChannelElement *sce); + if (ac->oc[1].m4ac.object_type == AOT_ER_AAC_LD) + imdct_and_window = imdct_and_windowing_ld; + else + imdct_and_window = imdct_and_windowing; for (type = 3; type >= 0; type--) { for (i = 0; i < MAX_ELEM_ID; i++) { ChannelElement *che = ac->che[type][i]; @@ -2431,11 +2486,11 @@ static void spectral_to_sample(AACContext *ac) if (type <= TYPE_CPE) apply_channel_coupling(ac, che, type, i, BETWEEN_TNS_AND_IMDCT, apply_dependent_coupling); if (type != TYPE_CCE || che->coup.coupling_point == AFTER_IMDCT) { - imdct_and_windowing(ac, &che->ch[0]); + imdct_and_window(ac, &che->ch[0]); if (ac->oc[1].m4ac.object_type == AOT_AAC_LTP) update_ltp(ac, &che->ch[0]); if (type == TYPE_CPE) { - imdct_and_windowing(ac, &che->ch[1]); + imdct_and_window(ac, &che->ch[1]); if (ac->oc[1].m4ac.object_type == AOT_AAC_LTP) update_ltp(ac, &che->ch[1]); } @@ -2503,6 +2558,9 @@ static int aac_decode_er_frame(AVCodecContext *avctx, void *data, int samples = 1024; int chan_config = ac->oc[1].m4ac.chan_config; + if (ac->oc[1].m4ac.object_type == AOT_ER_AAC_LD) + samples >>= 1; + ac->frame = data; if ((err = frame_configure_elements(avctx)) < 0) @@ -2757,6 +2815,7 @@ static av_cold int aac_decode_close(AVCodecContext *avctx) ff_mdct_end(&ac->mdct); ff_mdct_end(&ac->mdct_small); + ff_mdct_end(&ac->mdct_ld); ff_mdct_end(&ac->mdct_ltp); return 0; } -- cgit v1.2.3