1 /*
2 * Copyright (c) 2018 Chris Johnson
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to deal
6 * in the Software without restriction, including without limitation the rights
7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8 * copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in all
12 * copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20 * SOFTWARE.
21 */
22
23 #include "libavutil/channel_layout.h"
24 #include "libavutil/opt.h"
25 #include "avfilter.h"
26 #include "audio.h"
27 #include "formats.h"
28
29 typedef struct DeesserChannel {
30 double s1, s2, s3;
31 double m1, m2;
32 double ratioA, ratioB;
33 double iirSampleA, iirSampleB;
34 int flip;
35 } DeesserChannel;
36
37 typedef struct DeesserContext {
38 const AVClass *class;
39
40 double intensity;
41 double max;
42 double frequency;
43 int mode;
44
45 DeesserChannel *chan;
46 } DeesserContext;
47
48 enum OutModes {
49 IN_MODE,
50 OUT_MODE,
51 ESS_MODE,
52 NB_MODES
53 };
54
55 #define OFFSET(x) offsetof(DeesserContext, x)
56 #define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
57
58 static const AVOption deesser_options[] = {
59 { "i", "set intensity", OFFSET(intensity), AV_OPT_TYPE_DOUBLE, {.dbl=0.0}, 0.0, 1.0, A },
60 { "m", "set max deessing", OFFSET(max), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0.0, 1.0, A },
61 { "f", "set frequency", OFFSET(frequency), AV_OPT_TYPE_DOUBLE, {.dbl=0.5}, 0.0, 1.0, A },
62 { "s", "set output mode", OFFSET(mode), AV_OPT_TYPE_INT, {.i64=OUT_MODE}, 0, NB_MODES-1, A, "mode" },
63 { "i", "input", 0, AV_OPT_TYPE_CONST, {.i64=IN_MODE}, 0, 0, A, "mode" },
64 { "o", "output", 0, AV_OPT_TYPE_CONST, {.i64=OUT_MODE}, 0, 0, A, "mode" },
65 { "e", "ess", 0, AV_OPT_TYPE_CONST, {.i64=ESS_MODE}, 0, 0, A, "mode" },
66 { NULL }
67 };
68
69 AVFILTER_DEFINE_CLASS(deesser);
70
config_input(AVFilterLink * inlink)71 static int config_input(AVFilterLink *inlink)
72 {
73 AVFilterContext *ctx = inlink->dst;
74 DeesserContext *s = ctx->priv;
75
76 s->chan = av_calloc(inlink->ch_layout.nb_channels, sizeof(*s->chan));
77 if (!s->chan)
78 return AVERROR(ENOMEM);
79
80 for (int i = 0; i < inlink->ch_layout.nb_channels; i++) {
81 DeesserChannel *chan = &s->chan[i];
82
83 chan->ratioA = chan->ratioB = 1.0;
84 }
85
86 return 0;
87 }
88
filter_frame(AVFilterLink * inlink,AVFrame * in)89 static int filter_frame(AVFilterLink *inlink, AVFrame *in)
90 {
91 AVFilterContext *ctx = inlink->dst;
92 AVFilterLink *outlink = ctx->outputs[0];
93 DeesserContext *s = ctx->priv;
94 AVFrame *out;
95
96 if (av_frame_is_writable(in)) {
97 out = in;
98 } else {
99 out = ff_get_audio_buffer(outlink, in->nb_samples);
100 if (!out) {
101 av_frame_free(&in);
102 return AVERROR(ENOMEM);
103 }
104 av_frame_copy_props(out, in);
105 }
106
107 for (int ch = 0; ch < inlink->ch_layout.nb_channels; ch++) {
108 DeesserChannel *dec = &s->chan[ch];
109 double *src = (double *)in->extended_data[ch];
110 double *dst = (double *)out->extended_data[ch];
111 double overallscale = inlink->sample_rate < 44100 ? 44100.0 / inlink->sample_rate : inlink->sample_rate / 44100.0;
112 double intensity = pow(s->intensity, 5) * (8192 / overallscale);
113 double maxdess = 1.0 / pow(10.0, ((s->max - 1.0) * 48.0) / 20);
114 double iirAmount = pow(s->frequency, 2) / overallscale;
115 double offset;
116 double sense;
117 double recovery;
118 double attackspeed;
119
120 for (int i = 0; i < in->nb_samples; i++) {
121 double sample = src[i];
122
123 dec->s3 = dec->s2;
124 dec->s2 = dec->s1;
125 dec->s1 = sample;
126 dec->m1 = (dec->s1 - dec->s2) * ((dec->s1 - dec->s2) / 1.3);
127 dec->m2 = (dec->s2 - dec->s3) * ((dec->s1 - dec->s2) / 1.3);
128 sense = (dec->m1 - dec->m2) * ((dec->m1 - dec->m2) / 1.3);
129 attackspeed = 7.0 + sense * 1024;
130
131 sense = 1.0 + intensity * intensity * sense;
132 sense = FFMIN(sense, intensity);
133 recovery = 1.0 + (0.01 / sense);
134
135 offset = 1.0 - fabs(sample);
136
137 if (dec->flip) {
138 dec->iirSampleA = (dec->iirSampleA * (1.0 - (offset * iirAmount))) +
139 (sample * (offset * iirAmount));
140 if (dec->ratioA < sense) {
141 dec->ratioA = ((dec->ratioA * attackspeed) + sense) / (attackspeed + 1.0);
142 } else {
143 dec->ratioA = 1.0 + ((dec->ratioA - 1.0) / recovery);
144 }
145
146 dec->ratioA = FFMIN(dec->ratioA, maxdess);
147 sample = dec->iirSampleA + ((sample - dec->iirSampleA) / dec->ratioA);
148 } else {
149 dec->iirSampleB = (dec->iirSampleB * (1.0 - (offset * iirAmount))) +
150 (sample * (offset * iirAmount));
151 if (dec->ratioB < sense) {
152 dec->ratioB = ((dec->ratioB * attackspeed) + sense) / (attackspeed + 1.0);
153 } else {
154 dec->ratioB = 1.0 + ((dec->ratioB - 1.0) / recovery);
155 }
156
157 dec->ratioB = FFMIN(dec->ratioB, maxdess);
158 sample = dec->iirSampleB + ((sample - dec->iirSampleB) / dec->ratioB);
159 }
160
161 dec->flip = !dec->flip;
162
163 if (ctx->is_disabled)
164 sample = src[i];
165
166 switch (s->mode) {
167 case IN_MODE: dst[i] = src[i]; break;
168 case OUT_MODE: dst[i] = sample; break;
169 case ESS_MODE: dst[i] = src[i] - sample; break;
170 }
171 }
172 }
173
174 if (out != in)
175 av_frame_free(&in);
176
177 return ff_filter_frame(outlink, out);
178 }
179
uninit(AVFilterContext * ctx)180 static av_cold void uninit(AVFilterContext *ctx)
181 {
182 DeesserContext *s = ctx->priv;
183
184 av_freep(&s->chan);
185 }
186
187 static const AVFilterPad inputs[] = {
188 {
189 .name = "default",
190 .type = AVMEDIA_TYPE_AUDIO,
191 .filter_frame = filter_frame,
192 .config_props = config_input,
193 },
194 };
195
196 static const AVFilterPad outputs[] = {
197 {
198 .name = "default",
199 .type = AVMEDIA_TYPE_AUDIO,
200 },
201 };
202
203 const AVFilter ff_af_deesser = {
204 .name = "deesser",
205 .description = NULL_IF_CONFIG_SMALL("Apply de-essing to the audio."),
206 .priv_size = sizeof(DeesserContext),
207 .priv_class = &deesser_class,
208 .uninit = uninit,
209 FILTER_INPUTS(inputs),
210 FILTER_OUTPUTS(outputs),
211 FILTER_SINGLE_SAMPLEFMT(AV_SAMPLE_FMT_DBLP),
212 .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_INTERNAL,
213 };
214