| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | /* | ||
| 2 | * Copyright (c) 2023 Paul B Mahol | ||
| 3 | * | ||
| 4 | * This file is part of FFmpeg. | ||
| 5 | * | ||
| 6 | * FFmpeg is free software; you can redistribute it and/or | ||
| 7 | * modify it under the terms of the GNU Lesser General Public | ||
| 8 | * License as published by the Free Software Foundation; either | ||
| 9 | * version 2.1 of the License, or (at your option) any later version. | ||
| 10 | * | ||
| 11 | * FFmpeg is distributed in the hope that it will be useful, | ||
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
| 14 | * Lesser General Public License for more details. | ||
| 15 | * | ||
| 16 | * You should have received a copy of the GNU Lesser General Public | ||
| 17 | * License along with FFmpeg; if not, write to the Free Software | ||
| 18 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
| 19 | */ | ||
| 20 | |||
| 21 | #include "libavutil/channel_layout.h" | ||
| 22 | #include "libavutil/opt.h" | ||
| 23 | |||
| 24 | #include "audio.h" | ||
| 25 | #include "avfilter.h" | ||
| 26 | #include "filters.h" | ||
| 27 | #include "formats.h" | ||
| 28 | #include "internal.h" | ||
| 29 | |||
| 30 | typedef struct AFDelaySrcContext { | ||
| 31 | const AVClass *class; | ||
| 32 | |||
| 33 | double delay; | ||
| 34 | int sample_rate; | ||
| 35 | int nb_samples; | ||
| 36 | int nb_taps; | ||
| 37 | AVChannelLayout chlayout; | ||
| 38 | |||
| 39 | int64_t pts; | ||
| 40 | } AFDelaySrcContext; | ||
| 41 | |||
| 42 | ✗ | static float sincf(float x) | |
| 43 | { | ||
| 44 | ✗ | if (x == 0.f) | |
| 45 | ✗ | return 1.f; | |
| 46 | ✗ | return sinf(M_PI * x) / (M_PI * x); | |
| 47 | } | ||
| 48 | |||
| 49 | ✗ | static int activate(AVFilterContext *ctx) | |
| 50 | { | ||
| 51 | ✗ | AVFilterLink *outlink = ctx->outputs[0]; | |
| 52 | ✗ | AFDelaySrcContext *s = ctx->priv; | |
| 53 | ✗ | AVFrame *frame = NULL; | |
| 54 | int nb_samples; | ||
| 55 | float *dst; | ||
| 56 | |||
| 57 | ✗ | if (!ff_outlink_frame_wanted(outlink)) | |
| 58 | ✗ | return FFERROR_NOT_READY; | |
| 59 | |||
| 60 | ✗ | nb_samples = FFMIN(s->nb_samples, s->nb_taps - s->pts); | |
| 61 | ✗ | if (nb_samples <= 0) { | |
| 62 | ✗ | ff_outlink_set_status(outlink, AVERROR_EOF, s->pts); | |
| 63 | ✗ | return 0; | |
| 64 | } | ||
| 65 | |||
| 66 | ✗ | if (!(frame = ff_get_audio_buffer(outlink, nb_samples))) | |
| 67 | ✗ | return AVERROR(ENOMEM); | |
| 68 | |||
| 69 | ✗ | dst = (float *)frame->extended_data[0]; | |
| 70 | ✗ | for (int n = 0; n < nb_samples; n++) { | |
| 71 | ✗ | float x = s->pts + n; | |
| 72 | ✗ | dst[n] = sincf(x - s->delay) * cosf(M_PI * (x - s->delay) / s->nb_taps) / sincf((x - s->delay) / s->nb_taps); | |
| 73 | } | ||
| 74 | |||
| 75 | ✗ | for (int ch = 1; ch < frame->ch_layout.nb_channels; ch++) | |
| 76 | ✗ | memcpy(frame->extended_data[ch], dst, sizeof(*dst) * nb_samples); | |
| 77 | |||
| 78 | ✗ | frame->pts = s->pts; | |
| 79 | ✗ | s->pts += nb_samples; | |
| 80 | |||
| 81 | ✗ | return ff_filter_frame(outlink, frame); | |
| 82 | } | ||
| 83 | |||
| 84 | ✗ | static int query_formats(AVFilterContext *ctx) | |
| 85 | { | ||
| 86 | ✗ | AFDelaySrcContext *s = ctx->priv; | |
| 87 | ✗ | AVChannelLayout chlayouts[] = { s->chlayout, { 0 } }; | |
| 88 | ✗ | int sample_rates[] = { s->sample_rate, -1 }; | |
| 89 | static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_FLTP, | ||
| 90 | AV_SAMPLE_FMT_NONE }; | ||
| 91 | ✗ | int ret = ff_set_common_formats_from_list(ctx, sample_fmts); | |
| 92 | ✗ | if (ret < 0) | |
| 93 | ✗ | return ret; | |
| 94 | |||
| 95 | ✗ | ret = ff_set_common_channel_layouts_from_list(ctx, chlayouts); | |
| 96 | ✗ | if (ret < 0) | |
| 97 | ✗ | return ret; | |
| 98 | |||
| 99 | ✗ | return ff_set_common_samplerates_from_list(ctx, sample_rates); | |
| 100 | } | ||
| 101 | |||
| 102 | ✗ | static int config_output(AVFilterLink *outlink) | |
| 103 | { | ||
| 104 | ✗ | AVFilterContext *ctx = outlink->src; | |
| 105 | ✗ | AFDelaySrcContext *s = ctx->priv; | |
| 106 | |||
| 107 | ✗ | outlink->sample_rate = s->sample_rate; | |
| 108 | ✗ | s->pts = 0; | |
| 109 | ✗ | if (s->nb_taps <= 0) | |
| 110 | ✗ | s->nb_taps = s->delay * 8 + 1; | |
| 111 | |||
| 112 | ✗ | return 0; | |
| 113 | } | ||
| 114 | |||
| 115 | static const AVFilterPad afdelaysrc_outputs[] = { | ||
| 116 | { | ||
| 117 | .name = "default", | ||
| 118 | .type = AVMEDIA_TYPE_AUDIO, | ||
| 119 | .config_props = config_output, | ||
| 120 | }, | ||
| 121 | }; | ||
| 122 | |||
| 123 | #define AF AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM | ||
| 124 | #define OFFSET(x) offsetof(AFDelaySrcContext, x) | ||
| 125 | |||
| 126 | static const AVOption afdelaysrc_options[] = { | ||
| 127 | { "delay", "set fractional delay", OFFSET(delay), AV_OPT_TYPE_DOUBLE,{.dbl=0}, 0, INT16_MAX, AF }, | ||
| 128 | { "d", "set fractional delay", OFFSET(delay), AV_OPT_TYPE_DOUBLE,{.dbl=0}, 0, INT16_MAX, AF }, | ||
| 129 | { "sample_rate", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64=44100}, 1, INT_MAX, AF }, | ||
| 130 | { "r", "set sample rate", OFFSET(sample_rate), AV_OPT_TYPE_INT, {.i64=44100}, 1, INT_MAX, AF }, | ||
| 131 | { "nb_samples", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64=1024}, 1, INT_MAX, AF }, | ||
| 132 | { "n", "set the number of samples per requested frame", OFFSET(nb_samples), AV_OPT_TYPE_INT, {.i64=1024}, 1, INT_MAX, AF }, | ||
| 133 | { "taps", "set number of taps for delay filter", OFFSET(nb_taps), AV_OPT_TYPE_INT, {.i64=0}, 0, 32768, AF }, | ||
| 134 | { "t", "set number of taps for delay filter", OFFSET(nb_taps), AV_OPT_TYPE_INT, {.i64=0}, 0, 32768, AF }, | ||
| 135 | { "channel_layout", "set channel layout", OFFSET(chlayout), AV_OPT_TYPE_CHLAYOUT,{.str="stereo"},0, 0, AF }, | ||
| 136 | { "c", "set channel layout", OFFSET(chlayout), AV_OPT_TYPE_CHLAYOUT,{.str="stereo"},0, 0, AF }, | ||
| 137 | { NULL } | ||
| 138 | }; | ||
| 139 | |||
| 140 | AVFILTER_DEFINE_CLASS(afdelaysrc); | ||
| 141 | |||
| 142 | const AVFilter ff_asrc_afdelaysrc = { | ||
| 143 | .name = "afdelaysrc", | ||
| 144 | .description = NULL_IF_CONFIG_SMALL("Generate a Fractional delay FIR coefficients."), | ||
| 145 | .priv_size = sizeof(AFDelaySrcContext), | ||
| 146 | .priv_class = &afdelaysrc_class, | ||
| 147 | .activate = activate, | ||
| 148 | .inputs = NULL, | ||
| 149 | FILTER_OUTPUTS(afdelaysrc_outputs), | ||
| 150 | FILTER_QUERY_FUNC(query_formats), | ||
| 151 | }; | ||
| 152 |