| Line | Branch | Exec | Source |
|---|---|---|---|
| 1 | /* | ||
| 2 | * This file is part of FFmpeg. | ||
| 3 | * | ||
| 4 | * FFmpeg is free software; you can redistribute it and/or | ||
| 5 | * modify it under the terms of the GNU Lesser General Public | ||
| 6 | * License as published by the Free Software Foundation; either | ||
| 7 | * version 2.1 of the License, or (at your option) any later version. | ||
| 8 | * | ||
| 9 | * FFmpeg is distributed in the hope that it will be useful, | ||
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | ||
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
| 12 | * Lesser General Public License for more details. | ||
| 13 | * | ||
| 14 | * You should have received a copy of the GNU Lesser General Public | ||
| 15 | * License along with FFmpeg; if not, write to the Free Software | ||
| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | ||
| 17 | */ | ||
| 18 | |||
| 19 | #include "libavutil/channel_layout.h" | ||
| 20 | #include "libavutil/ffmath.h" | ||
| 21 | #include "libavutil/opt.h" | ||
| 22 | #include "avfilter.h" | ||
| 23 | #include "audio.h" | ||
| 24 | #include "filters.h" | ||
| 25 | |||
| 26 | #define MAX_ORDER 30 | ||
| 27 | |||
| 28 | typedef struct Coeffs { | ||
| 29 | double g; | ||
| 30 | double a1; | ||
| 31 | double b0, b1; | ||
| 32 | } Coeffs; | ||
| 33 | |||
| 34 | typedef struct ATiltContext { | ||
| 35 | const AVClass *class; | ||
| 36 | |||
| 37 | double freq; | ||
| 38 | double level; | ||
| 39 | double slope; | ||
| 40 | double width; | ||
| 41 | int order; | ||
| 42 | |||
| 43 | Coeffs coeffs[MAX_ORDER]; | ||
| 44 | |||
| 45 | AVFrame *w; | ||
| 46 | |||
| 47 | int (*filter_channels)(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs); | ||
| 48 | } ATiltContext; | ||
| 49 | |||
| 50 | ✗ | static double prewarp(double w, double T, double wp) | |
| 51 | { | ||
| 52 | ✗ | return wp * tan(w * T * 0.5) / tan(wp * T * 0.5); | |
| 53 | } | ||
| 54 | |||
| 55 | ✗ | static double mz(int i, double w0, double r, double alpha) | |
| 56 | { | ||
| 57 | ✗ | return w0 * pow(r, -alpha + i); | |
| 58 | } | ||
| 59 | |||
| 60 | ✗ | static double mp(int i, double w0, double r) | |
| 61 | { | ||
| 62 | ✗ | return w0 * pow(r, i); | |
| 63 | } | ||
| 64 | |||
| 65 | ✗ | static double mzh(int i, double T, double w0, double r, double alpha) | |
| 66 | { | ||
| 67 | ✗ | return prewarp(mz(i, w0, r, alpha), T, w0); | |
| 68 | } | ||
| 69 | |||
| 70 | ✗ | static double mph(int i, double T, double w0, double r) | |
| 71 | { | ||
| 72 | ✗ | return prewarp(mp(i, w0, r), T, w0); | |
| 73 | } | ||
| 74 | |||
| 75 | ✗ | static void set_tf1s(Coeffs *coeffs, double b1, double b0, double a0, | |
| 76 | double w1, double sr, double alpha) | ||
| 77 | { | ||
| 78 | ✗ | double c = 1.0 / tan(w1 * 0.5 / sr); | |
| 79 | ✗ | double d = a0 + c; | |
| 80 | |||
| 81 | ✗ | coeffs->b1 = (b0 - b1 * c) / d; | |
| 82 | ✗ | coeffs->b0 = (b0 + b1 * c) / d; | |
| 83 | ✗ | coeffs->a1 = (a0 - c) / d; | |
| 84 | ✗ | coeffs->g = a0 / b0; | |
| 85 | ✗ | } | |
| 86 | |||
| 87 | ✗ | static void set_filter(AVFilterContext *ctx, | |
| 88 | int order, double sr, double f0, | ||
| 89 | double bw, double alpha) | ||
| 90 | { | ||
| 91 | ✗ | ATiltContext *s = ctx->priv; | |
| 92 | ✗ | const double w0 = 2. * M_PI * f0; | |
| 93 | ✗ | const double f1 = f0 + bw; | |
| 94 | ✗ | const double w1 = 1.; | |
| 95 | ✗ | const double r = pow(f1 / f0, 1.0 / (order - 1.0)); | |
| 96 | ✗ | const double T = 1. / sr; | |
| 97 | |||
| 98 | ✗ | for (int i = 0; i < order; i++) { | |
| 99 | ✗ | Coeffs *coeffs = &s->coeffs[i]; | |
| 100 | |||
| 101 | ✗ | set_tf1s(coeffs, 1.0, mzh(i, T, w0, r, alpha), mph(i, T, w0, r), | |
| 102 | w1, sr, alpha); | ||
| 103 | } | ||
| 104 | ✗ | } | |
| 105 | |||
| 106 | ✗ | static int get_coeffs(AVFilterContext *ctx) | |
| 107 | { | ||
| 108 | ✗ | ATiltContext *s = ctx->priv; | |
| 109 | ✗ | AVFilterLink *inlink = ctx->inputs[0]; | |
| 110 | |||
| 111 | ✗ | set_filter(ctx, s->order, inlink->sample_rate, s->freq, s->width, s->slope); | |
| 112 | |||
| 113 | ✗ | return 0; | |
| 114 | } | ||
| 115 | |||
| 116 | typedef struct ThreadData { | ||
| 117 | AVFrame *in, *out; | ||
| 118 | } ThreadData; | ||
| 119 | |||
| 120 | #define FILTER(name, type) \ | ||
| 121 | static int filter_channels_## name(AVFilterContext *ctx, void *arg, \ | ||
| 122 | int jobnr, int nb_jobs) \ | ||
| 123 | { \ | ||
| 124 | ATiltContext *s = ctx->priv; \ | ||
| 125 | ThreadData *td = arg; \ | ||
| 126 | AVFrame *out = td->out; \ | ||
| 127 | AVFrame *in = td->in; \ | ||
| 128 | const int start = (in->ch_layout.nb_channels * jobnr) / nb_jobs; \ | ||
| 129 | const int end = (in->ch_layout.nb_channels * (jobnr+1)) / nb_jobs; \ | ||
| 130 | const type level = s->level; \ | ||
| 131 | \ | ||
| 132 | for (int ch = start; ch < end; ch++) { \ | ||
| 133 | const type *src = (const type *)in->extended_data[ch]; \ | ||
| 134 | type *dst = (type *)out->extended_data[ch]; \ | ||
| 135 | \ | ||
| 136 | for (int b = 0; b < s->order; b++) { \ | ||
| 137 | Coeffs *coeffs = &s->coeffs[b]; \ | ||
| 138 | const type g = coeffs->g; \ | ||
| 139 | const type a1 = coeffs->a1; \ | ||
| 140 | const type b0 = coeffs->b0; \ | ||
| 141 | const type b1 = coeffs->b1; \ | ||
| 142 | type *w = ((type *)s->w->extended_data[ch]) + b * 2; \ | ||
| 143 | \ | ||
| 144 | for (int n = 0; n < in->nb_samples; n++) { \ | ||
| 145 | type sain = b ? dst[n] : src[n] * level; \ | ||
| 146 | type saout = sain * b0 + w[0] * b1 - w[1] * a1; \ | ||
| 147 | \ | ||
| 148 | w[0] = sain; \ | ||
| 149 | w[1] = saout; \ | ||
| 150 | \ | ||
| 151 | dst[n] = saout * g; \ | ||
| 152 | } \ | ||
| 153 | } \ | ||
| 154 | } \ | ||
| 155 | \ | ||
| 156 | return 0; \ | ||
| 157 | } | ||
| 158 | |||
| 159 | ✗ | FILTER(fltp, float) | |
| 160 | ✗ | FILTER(dblp, double) | |
| 161 | |||
| 162 | ✗ | static int config_input(AVFilterLink *inlink) | |
| 163 | { | ||
| 164 | ✗ | AVFilterContext *ctx = inlink->dst; | |
| 165 | ✗ | ATiltContext *s = ctx->priv; | |
| 166 | |||
| 167 | ✗ | switch (inlink->format) { | |
| 168 | ✗ | case AV_SAMPLE_FMT_FLTP: s->filter_channels = filter_channels_fltp; break; | |
| 169 | ✗ | case AV_SAMPLE_FMT_DBLP: s->filter_channels = filter_channels_dblp; break; | |
| 170 | } | ||
| 171 | |||
| 172 | ✗ | s->w = ff_get_audio_buffer(inlink, 2 * MAX_ORDER); | |
| 173 | ✗ | if (!s->w) | |
| 174 | ✗ | return AVERROR(ENOMEM); | |
| 175 | |||
| 176 | ✗ | return get_coeffs(ctx); | |
| 177 | } | ||
| 178 | |||
| 179 | ✗ | static int filter_frame(AVFilterLink *inlink, AVFrame *in) | |
| 180 | { | ||
| 181 | ✗ | AVFilterContext *ctx = inlink->dst; | |
| 182 | ✗ | ATiltContext *s = ctx->priv; | |
| 183 | ✗ | AVFilterLink *outlink = ctx->outputs[0]; | |
| 184 | ThreadData td; | ||
| 185 | AVFrame *out; | ||
| 186 | |||
| 187 | ✗ | if (av_frame_is_writable(in)) { | |
| 188 | ✗ | out = in; | |
| 189 | } else { | ||
| 190 | ✗ | out = ff_get_audio_buffer(outlink, in->nb_samples); | |
| 191 | ✗ | if (!out) { | |
| 192 | ✗ | av_frame_free(&in); | |
| 193 | ✗ | return AVERROR(ENOMEM); | |
| 194 | } | ||
| 195 | ✗ | av_frame_copy_props(out, in); | |
| 196 | } | ||
| 197 | |||
| 198 | ✗ | td.in = in; td.out = out; | |
| 199 | ✗ | ff_filter_execute(ctx, s->filter_channels, &td, NULL, FFMIN(inlink->ch_layout.nb_channels, | |
| 200 | ff_filter_get_nb_threads(ctx))); | ||
| 201 | |||
| 202 | ✗ | if (out != in) | |
| 203 | ✗ | av_frame_free(&in); | |
| 204 | ✗ | return ff_filter_frame(outlink, out); | |
| 205 | } | ||
| 206 | |||
| 207 | ✗ | static int process_command(AVFilterContext *ctx, const char *cmd, const char *args, | |
| 208 | char *res, int res_len, int flags) | ||
| 209 | { | ||
| 210 | int ret; | ||
| 211 | |||
| 212 | ✗ | ret = ff_filter_process_command(ctx, cmd, args, res, res_len, flags); | |
| 213 | ✗ | if (ret < 0) | |
| 214 | ✗ | return ret; | |
| 215 | |||
| 216 | ✗ | return get_coeffs(ctx); | |
| 217 | } | ||
| 218 | |||
| 219 | ✗ | static av_cold void uninit(AVFilterContext *ctx) | |
| 220 | { | ||
| 221 | ✗ | ATiltContext *s = ctx->priv; | |
| 222 | |||
| 223 | ✗ | av_frame_free(&s->w); | |
| 224 | ✗ | } | |
| 225 | |||
| 226 | #define OFFSET(x) offsetof(ATiltContext, x) | ||
| 227 | #define FLAGS AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_RUNTIME_PARAM | ||
| 228 | |||
| 229 | static const AVOption atilt_options[] = { | ||
| 230 | { "freq", "set central frequency",OFFSET(freq), AV_OPT_TYPE_DOUBLE, {.dbl=10000}, 20, 192000, FLAGS }, | ||
| 231 | { "slope", "set filter slope", OFFSET(slope), AV_OPT_TYPE_DOUBLE, {.dbl=0}, -1, 1, FLAGS }, | ||
| 232 | { "width", "set filter width", OFFSET(width), AV_OPT_TYPE_DOUBLE, {.dbl=1000}, 100, 10000, FLAGS }, | ||
| 233 | { "order", "set filter order", OFFSET(order), AV_OPT_TYPE_INT, {.i64=5}, 2,MAX_ORDER, FLAGS }, | ||
| 234 | { "level", "set input level", OFFSET(level), AV_OPT_TYPE_DOUBLE, {.dbl=1.}, 0., 4., FLAGS }, | ||
| 235 | { NULL } | ||
| 236 | }; | ||
| 237 | |||
| 238 | AVFILTER_DEFINE_CLASS(atilt); | ||
| 239 | |||
| 240 | static const AVFilterPad inputs[] = { | ||
| 241 | { | ||
| 242 | .name = "default", | ||
| 243 | .type = AVMEDIA_TYPE_AUDIO, | ||
| 244 | .filter_frame = filter_frame, | ||
| 245 | .config_props = config_input, | ||
| 246 | }, | ||
| 247 | }; | ||
| 248 | |||
| 249 | const FFFilter ff_af_atilt = { | ||
| 250 | .p.name = "atilt", | ||
| 251 | .p.description = NULL_IF_CONFIG_SMALL("Apply spectral tilt to audio."), | ||
| 252 | .p.priv_class = &atilt_class, | ||
| 253 | .p.flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC | | ||
| 254 | AVFILTER_FLAG_SLICE_THREADS, | ||
| 255 | .priv_size = sizeof(ATiltContext), | ||
| 256 | .uninit = uninit, | ||
| 257 | FILTER_INPUTS(inputs), | ||
| 258 | FILTER_OUTPUTS(ff_audio_default_filterpad), | ||
| 259 | FILTER_SAMPLEFMTS(AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_DBLP), | ||
| 260 | .process_command = process_command, | ||
| 261 | }; | ||
| 262 |