| /* |
| * Copyright (c) 2019 The FFmpeg Project |
| * |
| * This file is part of FFmpeg. |
| * |
| * FFmpeg is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * FFmpeg is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with FFmpeg; if not, write to the Free Software |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| */ |
| |
| #include "libavutil/channel_layout.h" |
| #include "libavutil/opt.h" |
| #include "avfilter.h" |
| #include "audio.h" |
| #include "formats.h" |
| |
| enum ASoftClipTypes { |
| ASC_TANH, |
| ASC_ATAN, |
| ASC_CUBIC, |
| ASC_EXP, |
| ASC_ALG, |
| ASC_QUINTIC, |
| ASC_SIN, |
| NB_TYPES, |
| }; |
| |
| typedef struct ASoftClipContext { |
| const AVClass *class; |
| |
| int type; |
| double param; |
| |
| void (*filter)(struct ASoftClipContext *s, void **dst, const void **src, |
| int nb_samples, int channels); |
| } ASoftClipContext; |
| |
| #define OFFSET(x) offsetof(ASoftClipContext, x) |
| #define A AV_OPT_FLAG_AUDIO_PARAM|AV_OPT_FLAG_FILTERING_PARAM |
| |
| static const AVOption asoftclip_options[] = { |
| { "type", "set softclip type", OFFSET(type), AV_OPT_TYPE_INT, {.i64=0}, 0, NB_TYPES-1, A, "types" }, |
| { "tanh", NULL, 0, AV_OPT_TYPE_CONST, {.i64=ASC_TANH}, 0, 0, A, "types" }, |
| { "atan", NULL, 0, AV_OPT_TYPE_CONST, {.i64=ASC_ATAN}, 0, 0, A, "types" }, |
| { "cubic", NULL, 0, AV_OPT_TYPE_CONST, {.i64=ASC_CUBIC}, 0, 0, A, "types" }, |
| { "exp", NULL, 0, AV_OPT_TYPE_CONST, {.i64=ASC_EXP}, 0, 0, A, "types" }, |
| { "alg", NULL, 0, AV_OPT_TYPE_CONST, {.i64=ASC_ALG}, 0, 0, A, "types" }, |
| { "quintic", NULL, 0, AV_OPT_TYPE_CONST, {.i64=ASC_QUINTIC},0, 0, A, "types" }, |
| { "sin", NULL, 0, AV_OPT_TYPE_CONST, {.i64=ASC_SIN}, 0, 0, A, "types" }, |
| { "param", "set softclip parameter", OFFSET(param), AV_OPT_TYPE_DOUBLE, {.dbl=1}, 0.01, 3, A }, |
| { NULL } |
| }; |
| |
| AVFILTER_DEFINE_CLASS(asoftclip); |
| |
| static int query_formats(AVFilterContext *ctx) |
| { |
| AVFilterFormats *formats = NULL; |
| AVFilterChannelLayouts *layouts = NULL; |
| static const enum AVSampleFormat sample_fmts[] = { |
| AV_SAMPLE_FMT_FLT, AV_SAMPLE_FMT_FLTP, |
| AV_SAMPLE_FMT_DBL, AV_SAMPLE_FMT_DBLP, |
| AV_SAMPLE_FMT_NONE |
| }; |
| int ret; |
| |
| formats = ff_make_format_list(sample_fmts); |
| if (!formats) |
| return AVERROR(ENOMEM); |
| ret = ff_set_common_formats(ctx, formats); |
| if (ret < 0) |
| return ret; |
| |
| layouts = ff_all_channel_counts(); |
| if (!layouts) |
| return AVERROR(ENOMEM); |
| |
| ret = ff_set_common_channel_layouts(ctx, layouts); |
| if (ret < 0) |
| return ret; |
| |
| formats = ff_all_samplerates(); |
| return ff_set_common_samplerates(ctx, formats); |
| } |
| |
| #define SQR(x) ((x) * (x)) |
| |
| static void filter_flt(ASoftClipContext *s, |
| void **dptr, const void **sptr, |
| int nb_samples, int channels) |
| { |
| float param = s->param; |
| |
| for (int c = 0; c < channels; c++) { |
| const float *src = sptr[c]; |
| float *dst = dptr[c]; |
| |
| switch (s->type) { |
| case ASC_TANH: |
| for (int n = 0; n < nb_samples; n++) { |
| dst[n] = tanhf(src[n] * param); |
| } |
| break; |
| case ASC_ATAN: |
| for (int n = 0; n < nb_samples; n++) |
| dst[n] = 2.f / M_PI * atanf(src[n] * param); |
| break; |
| case ASC_CUBIC: |
| for (int n = 0; n < nb_samples; n++) { |
| if (FFABS(src[n]) >= 1.5f) |
| dst[n] = FFSIGN(src[n]); |
| else |
| dst[n] = src[n] - 0.1481f * powf(src[n], 3.f); |
| } |
| break; |
| case ASC_EXP: |
| for (int n = 0; n < nb_samples; n++) |
| dst[n] = 2.f / (1.f + expf(-2.f * src[n])) - 1.; |
| break; |
| case ASC_ALG: |
| for (int n = 0; n < nb_samples; n++) |
| dst[n] = src[n] / (sqrtf(param + src[n] * src[n])); |
| break; |
| case ASC_QUINTIC: |
| for (int n = 0; n < nb_samples; n++) { |
| if (FFABS(src[n]) >= 1.25) |
| dst[n] = FFSIGN(src[n]); |
| else |
| dst[n] = src[n] - 0.08192f * powf(src[n], 5.f); |
| } |
| break; |
| case ASC_SIN: |
| for (int n = 0; n < nb_samples; n++) { |
| if (FFABS(src[n]) >= M_PI_2) |
| dst[n] = FFSIGN(src[n]); |
| else |
| dst[n] = sinf(src[n]); |
| } |
| break; |
| } |
| } |
| } |
| |
| static void filter_dbl(ASoftClipContext *s, |
| void **dptr, const void **sptr, |
| int nb_samples, int channels) |
| { |
| double param = s->param; |
| |
| for (int c = 0; c < channels; c++) { |
| const double *src = sptr[c]; |
| double *dst = dptr[c]; |
| |
| switch (s->type) { |
| case ASC_TANH: |
| for (int n = 0; n < nb_samples; n++) { |
| dst[n] = tanh(src[n] * param); |
| } |
| break; |
| case ASC_ATAN: |
| for (int n = 0; n < nb_samples; n++) |
| dst[n] = 2. / M_PI * atan(src[n] * param); |
| break; |
| case ASC_CUBIC: |
| for (int n = 0; n < nb_samples; n++) { |
| if (FFABS(src[n]) >= 1.5) |
| dst[n] = FFSIGN(src[n]); |
| else |
| dst[n] = src[n] - 0.1481 * pow(src[n], 3.); |
| } |
| break; |
| case ASC_EXP: |
| for (int n = 0; n < nb_samples; n++) |
| dst[n] = 2. / (1. + exp(-2. * src[n])) - 1.; |
| break; |
| case ASC_ALG: |
| for (int n = 0; n < nb_samples; n++) |
| dst[n] = src[n] / (sqrt(param + src[n] * src[n])); |
| break; |
| case ASC_QUINTIC: |
| for (int n = 0; n < nb_samples; n++) { |
| if (FFABS(src[n]) >= 1.25) |
| dst[n] = FFSIGN(src[n]); |
| else |
| dst[n] = src[n] - 0.08192 * pow(src[n], 5.); |
| } |
| break; |
| case ASC_SIN: |
| for (int n = 0; n < nb_samples; n++) { |
| if (FFABS(src[n]) >= M_PI_2) |
| dst[n] = FFSIGN(src[n]); |
| else |
| dst[n] = sin(src[n]); |
| } |
| break; |
| } |
| } |
| } |
| |
| static int config_input(AVFilterLink *inlink) |
| { |
| AVFilterContext *ctx = inlink->dst; |
| ASoftClipContext *s = ctx->priv; |
| |
| switch (inlink->format) { |
| case AV_SAMPLE_FMT_FLT: |
| case AV_SAMPLE_FMT_FLTP: s->filter = filter_flt; break; |
| case AV_SAMPLE_FMT_DBL: |
| case AV_SAMPLE_FMT_DBLP: s->filter = filter_dbl; break; |
| } |
| |
| return 0; |
| } |
| |
| static int filter_frame(AVFilterLink *inlink, AVFrame *in) |
| { |
| AVFilterContext *ctx = inlink->dst; |
| AVFilterLink *outlink = ctx->outputs[0]; |
| ASoftClipContext *s = ctx->priv; |
| int nb_samples, channels; |
| AVFrame *out; |
| |
| if (av_frame_is_writable(in)) { |
| out = in; |
| } else { |
| out = ff_get_audio_buffer(outlink, in->nb_samples); |
| if (!out) { |
| av_frame_free(&in); |
| return AVERROR(ENOMEM); |
| } |
| av_frame_copy_props(out, in); |
| } |
| |
| if (av_sample_fmt_is_planar(in->format)) { |
| nb_samples = in->nb_samples; |
| channels = in->channels; |
| } else { |
| nb_samples = in->channels * in->nb_samples; |
| channels = 1; |
| } |
| |
| s->filter(s, (void **)out->extended_data, (const void **)in->extended_data, |
| nb_samples, channels); |
| |
| if (out != in) |
| av_frame_free(&in); |
| |
| return ff_filter_frame(outlink, out); |
| } |
| |
| static const AVFilterPad inputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_AUDIO, |
| .filter_frame = filter_frame, |
| .config_props = config_input, |
| }, |
| { NULL } |
| }; |
| |
| static const AVFilterPad outputs[] = { |
| { |
| .name = "default", |
| .type = AVMEDIA_TYPE_AUDIO, |
| }, |
| { NULL } |
| }; |
| |
| AVFilter ff_af_asoftclip = { |
| .name = "asoftclip", |
| .description = NULL_IF_CONFIG_SMALL("Audio Soft Clipper."), |
| .query_formats = query_formats, |
| .priv_size = sizeof(ASoftClipContext), |
| .priv_class = &asoftclip_class, |
| .inputs = inputs, |
| .outputs = outputs, |
| .flags = AVFILTER_FLAG_SUPPORT_TIMELINE_GENERIC, |
| }; |
