1 /*
2 * Copyright (c) 2021 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/common.h"
23 #include "libavutil/opt.h"
24
25 #include "audio.h"
26 #include "avfilter.h"
27 #include "formats.h"
28 #include "filters.h"
29 #include "internal.h"
30
31 typedef struct AudioSDRContext {
32 int channels;
33 int64_t pts;
34 double *sum_u;
35 double *sum_uv;
36
37 AVFrame *cache[2];
38 } AudioSDRContext;
39
sdr(AVFilterContext * ctx,const AVFrame * u,const AVFrame * v)40 static void sdr(AVFilterContext *ctx, const AVFrame *u, const AVFrame *v)
41 {
42 AudioSDRContext *s = ctx->priv;
43
44 for (int ch = 0; ch < u->ch_layout.nb_channels; ch++) {
45 const double *const us = (double *)u->extended_data[ch];
46 const double *const vs = (double *)v->extended_data[ch];
47 double sum_uv = s->sum_uv[ch];
48 double sum_u = s->sum_u[ch];
49
50 for (int n = 0; n < u->nb_samples; n++) {
51 sum_u += us[n] * us[n];
52 sum_uv += (us[n] - vs[n]) * (us[n] - vs[n]);
53 }
54
55 s->sum_uv[ch] = sum_uv;
56 s->sum_u[ch] = sum_u;
57 }
58 }
59
activate(AVFilterContext * ctx)60 static int activate(AVFilterContext *ctx)
61 {
62 AudioSDRContext *s = ctx->priv;
63 int ret, status;
64 int available;
65 int64_t pts;
66
67 FF_FILTER_FORWARD_STATUS_BACK_ALL(ctx->outputs[0], ctx);
68
69 available = FFMIN(ff_inlink_queued_samples(ctx->inputs[0]), ff_inlink_queued_samples(ctx->inputs[1]));
70 if (available > 0) {
71 AVFrame *out;
72
73 for (int i = 0; i < 2; i++) {
74 ret = ff_inlink_consume_samples(ctx->inputs[i], available, available, &s->cache[i]);
75 if (ret > 0) {
76 if (s->pts == AV_NOPTS_VALUE)
77 s->pts = s->cache[i]->pts;
78 }
79 }
80
81 sdr(ctx, s->cache[0], s->cache[1]);
82
83 av_frame_free(&s->cache[1]);
84 out = s->cache[0];
85 out->nb_samples = available;
86 out->pts = s->pts;
87 s->pts += available;
88 s->cache[0] = NULL;
89
90 return ff_filter_frame(ctx->outputs[0], out);
91 }
92
93 for (int i = 0; i < 2; i++) {
94 if (ff_inlink_acknowledge_status(ctx->inputs[i], &status, &pts)) {
95 ff_outlink_set_status(ctx->outputs[0], status, s->pts);
96 return 0;
97 }
98 }
99
100 if (ff_outlink_frame_wanted(ctx->outputs[0])) {
101 for (int i = 0; i < 2; i++) {
102 if (ff_inlink_queued_samples(ctx->inputs[i]) > 0)
103 continue;
104 ff_inlink_request_frame(ctx->inputs[i]);
105 }
106 return 0;
107 }
108
109 return FFERROR_NOT_READY;
110 }
111
config_output(AVFilterLink * outlink)112 static int config_output(AVFilterLink *outlink)
113 {
114 AVFilterContext *ctx = outlink->src;
115 AVFilterLink *inlink = ctx->inputs[0];
116 AudioSDRContext *s = ctx->priv;
117
118 s->pts = AV_NOPTS_VALUE;
119
120 s->channels = inlink->ch_layout.nb_channels;
121
122 s->sum_u = av_calloc(outlink->ch_layout.nb_channels, sizeof(*s->sum_u));
123 s->sum_uv = av_calloc(outlink->ch_layout.nb_channels, sizeof(*s->sum_uv));
124 if (!s->sum_u || !s->sum_uv)
125 return AVERROR(ENOMEM);
126
127 return 0;
128 }
129
uninit(AVFilterContext * ctx)130 static av_cold void uninit(AVFilterContext *ctx)
131 {
132 AudioSDRContext *s = ctx->priv;
133
134 for (int ch = 0; ch < s->channels; ch++)
135 av_log(ctx, AV_LOG_INFO, "SDR ch%d: %g dB\n", ch, 20. * log10(s->sum_u[ch] / s->sum_uv[ch]));
136
137 av_frame_free(&s->cache[0]);
138 av_frame_free(&s->cache[1]);
139
140 av_freep(&s->sum_u);
141 av_freep(&s->sum_uv);
142 }
143
144 static const AVFilterPad inputs[] = {
145 {
146 .name = "input0",
147 .type = AVMEDIA_TYPE_AUDIO,
148 },
149 {
150 .name = "input1",
151 .type = AVMEDIA_TYPE_AUDIO,
152 },
153 };
154
155 static const AVFilterPad outputs[] = {
156 {
157 .name = "default",
158 .type = AVMEDIA_TYPE_AUDIO,
159 .config_props = config_output,
160 },
161 };
162
163 const AVFilter ff_af_asdr = {
164 .name = "asdr",
165 .description = NULL_IF_CONFIG_SMALL("Measure Audio Signal-to-Distortion Ratio."),
166 .priv_size = sizeof(AudioSDRContext),
167 .activate = activate,
168 .uninit = uninit,
169 .flags = AVFILTER_FLAG_METADATA_ONLY,
170 FILTER_INPUTS(inputs),
171 FILTER_OUTPUTS(outputs),
172 FILTER_SINGLE_SAMPLEFMT(AV_SAMPLE_FMT_DBLP),
173 };
174