/* * Copyright (c) 2012 Clément Bœsch * * 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 */ /** * @file * audio to spectrum (video) transmedia filter, based on ffplay rdft showmode * (by Michael Niedermayer) and lavfi/avf_showwaves (by Stefano Sabatini). */ #include #include "libavcodec/avfft.h" #include "libavutil/avassert.h" #include "libavutil/channel_layout.h" #include "libavutil/opt.h" #include "avfilter.h" #include "internal.h" enum DisplayMode { COMBINED, SEPARATE, NB_MODES }; enum DisplayScale { LINEAR, SQRT, CBRT, LOG, NB_SCALES }; enum ColorMode { CHANNEL, INTENSITY, NB_CLMODES }; typedef struct { const AVClass *class; int w, h; AVFilterBufferRef *outpicref; int req_fullfilled; int nb_display_channels; int channel_height; int sliding; ///< 1 if sliding mode, 0 otherwise enum DisplayMode mode; ///< channel display mode enum ColorMode color_mode; ///< display color scheme enum DisplayScale scale; float saturation; ///< color saturation multiplier int xpos; ///< x position (current column) RDFTContext *rdft; ///< Real Discrete Fourier Transform context int rdft_bits; ///< number of bits (RDFT window size = 1<priv; int err; showspectrum->class = &showspectrum_class; av_opt_set_defaults(showspectrum); if ((err = av_set_options_string(showspectrum, args, "=", ":")) < 0) return err; return 0; } static av_cold void uninit(AVFilterContext *ctx) { ShowSpectrumContext *showspectrum = ctx->priv; int i; av_freep(&showspectrum->combine_buffer); av_rdft_end(showspectrum->rdft); for (i = 0; i < showspectrum->nb_display_channels; i++) av_freep(&showspectrum->rdft_data[i]); av_freep(&showspectrum->rdft_data); av_freep(&showspectrum->window_func_lut); avfilter_unref_bufferp(&showspectrum->outpicref); } static int query_formats(AVFilterContext *ctx) { AVFilterFormats *formats = NULL; AVFilterChannelLayouts *layouts = NULL; AVFilterLink *inlink = ctx->inputs[0]; AVFilterLink *outlink = ctx->outputs[0]; static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_S16P, AV_SAMPLE_FMT_NONE }; static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_NONE }; /* set input audio formats */ formats = ff_make_format_list(sample_fmts); if (!formats) return AVERROR(ENOMEM); ff_formats_ref(formats, &inlink->out_formats); layouts = ff_all_channel_layouts(); if (!layouts) return AVERROR(ENOMEM); ff_channel_layouts_ref(layouts, &inlink->out_channel_layouts); formats = ff_all_samplerates(); if (!formats) return AVERROR(ENOMEM); ff_formats_ref(formats, &inlink->out_samplerates); /* set output video format */ formats = ff_make_format_list(pix_fmts); if (!formats) return AVERROR(ENOMEM); ff_formats_ref(formats, &outlink->in_formats); return 0; } static int config_output(AVFilterLink *outlink) { AVFilterContext *ctx = outlink->src; AVFilterLink *inlink = ctx->inputs[0]; ShowSpectrumContext *showspectrum = ctx->priv; int i, rdft_bits, win_size, h; outlink->w = showspectrum->w; outlink->h = showspectrum->h; h = (showspectrum->mode == COMBINED) ? outlink->h : outlink->h / inlink->channels; showspectrum->channel_height = h; /* RDFT window size (precision) according to the requested output frame height */ for (rdft_bits = 1; 1 << rdft_bits < 2 * h; rdft_bits++); win_size = 1 << rdft_bits; /* (re-)configuration if the video output changed (or first init) */ if (rdft_bits != showspectrum->rdft_bits) { size_t rdft_size, rdft_listsize; AVFilterBufferRef *outpicref; av_rdft_end(showspectrum->rdft); showspectrum->rdft = av_rdft_init(rdft_bits, DFT_R2C); showspectrum->rdft_bits = rdft_bits; /* RDFT buffers: x2 for each (display) channel buffer. * Note: we use free and malloc instead of a realloc-like function to * make sure the buffer is aligned in memory for the FFT functions. */ for (i = 0; i < showspectrum->nb_display_channels; i++) av_freep(&showspectrum->rdft_data[i]); av_freep(&showspectrum->rdft_data); showspectrum->nb_display_channels = inlink->channels; if (av_size_mult(sizeof(*showspectrum->rdft_data), showspectrum->nb_display_channels, &rdft_listsize) < 0) return AVERROR(EINVAL); if (av_size_mult(sizeof(**showspectrum->rdft_data), win_size, &rdft_size) < 0) return AVERROR(EINVAL); showspectrum->rdft_data = av_malloc(rdft_listsize); if (!showspectrum->rdft_data) return AVERROR(ENOMEM); for (i = 0; i < showspectrum->nb_display_channels; i++) { showspectrum->rdft_data[i] = av_malloc(rdft_size); if (!showspectrum->rdft_data[i]) return AVERROR(ENOMEM); } showspectrum->filled = 0; /* pre-calc windowing function (hann here) */ showspectrum->window_func_lut = av_realloc_f(showspectrum->window_func_lut, win_size, sizeof(*showspectrum->window_func_lut)); if (!showspectrum->window_func_lut) return AVERROR(ENOMEM); for (i = 0; i < win_size; i++) showspectrum->window_func_lut[i] = .5f * (1 - cos(2*M_PI*i / (win_size-1))); /* prepare the initial picref buffer (black frame) */ avfilter_unref_bufferp(&showspectrum->outpicref); showspectrum->outpicref = outpicref = ff_get_video_buffer(outlink, AV_PERM_WRITE|AV_PERM_PRESERVE|AV_PERM_REUSE2, outlink->w, outlink->h); if (!outpicref) return AVERROR(ENOMEM); outlink->sample_aspect_ratio = (AVRational){1,1}; memset(outpicref->data[0], 0, outlink->h * outpicref->linesize[0]); } if (showspectrum->xpos >= outlink->w) showspectrum->xpos = 0; showspectrum->combine_buffer = av_realloc_f(showspectrum->combine_buffer, outlink->h * 3, sizeof(*showspectrum->combine_buffer)); av_log(ctx, AV_LOG_VERBOSE, "s:%dx%d RDFT window size:%d\n", showspectrum->w, showspectrum->h, win_size); return 0; } inline static void push_frame(AVFilterLink *outlink) { ShowSpectrumContext *showspectrum = outlink->src->priv; showspectrum->xpos++; if (showspectrum->xpos >= outlink->w) showspectrum->xpos = 0; showspectrum->filled = 0; showspectrum->req_fullfilled = 1; ff_filter_frame(outlink, avfilter_ref_buffer(showspectrum->outpicref, ~AV_PERM_WRITE)); } static int request_frame(AVFilterLink *outlink) { ShowSpectrumContext *showspectrum = outlink->src->priv; AVFilterLink *inlink = outlink->src->inputs[0]; int ret; showspectrum->req_fullfilled = 0; do { ret = ff_request_frame(inlink); } while (!showspectrum->req_fullfilled && ret >= 0); if (ret == AVERROR_EOF && showspectrum->outpicref) push_frame(outlink); return ret; } static int plot_spectrum_column(AVFilterLink *inlink, AVFilterBufferRef *insamples, int nb_samples) { AVFilterContext *ctx = inlink->dst; AVFilterLink *outlink = ctx->outputs[0]; ShowSpectrumContext *showspectrum = ctx->priv; AVFilterBufferRef *outpicref = showspectrum->outpicref; /* nb_freq contains the power of two superior or equal to the output image * height (or half the RDFT window size) */ const int nb_freq = 1 << (showspectrum->rdft_bits - 1); const int win_size = nb_freq << 1; const double w = 1. / (sqrt(nb_freq) * 32768.); int ch, plane, n, y; const int start = showspectrum->filled; const int add_samples = FFMIN(win_size - start, nb_samples); /* fill RDFT input with the number of samples available */ for (ch = 0; ch < showspectrum->nb_display_channels; ch++) { const int16_t *p = (int16_t *)insamples->extended_data[ch]; p += showspectrum->consumed; for (n = 0; n < add_samples; n++) showspectrum->rdft_data[ch][start + n] = p[n] * showspectrum->window_func_lut[start + n]; } showspectrum->filled += add_samples; /* complete RDFT window size? */ if (showspectrum->filled == win_size) { /* channel height */ int h = showspectrum->channel_height; /* run RDFT on each samples set */ for (ch = 0; ch < showspectrum->nb_display_channels; ch++) av_rdft_calc(showspectrum->rdft, showspectrum->rdft_data[ch]); /* fill a new spectrum column */ #define RE(y, ch) showspectrum->rdft_data[ch][2 * y + 0] #define IM(y, ch) showspectrum->rdft_data[ch][2 * y + 1] #define MAGNITUDE(y, ch) hypot(RE(y, ch), IM(y, ch)) /* initialize buffer for combining to black */ for (y = 0; y < outlink->h; y++) { showspectrum->combine_buffer[3 * y ] = 0; showspectrum->combine_buffer[3 * y + 1] = 127.5; showspectrum->combine_buffer[3 * y + 2] = 127.5; } for (ch = 0; ch < showspectrum->nb_display_channels; ch++) { float yf, uf, vf; /* decide color range */ switch (showspectrum->mode) { case COMBINED: // reduce range by channel count yf = 256.0f / showspectrum->nb_display_channels; switch (showspectrum->color_mode) { case INTENSITY: uf = yf; vf = yf; break; case CHANNEL: /* adjust saturation for mixed UV coloring */ /* this factor is correct for infinite channels, an approximation otherwise */ uf = yf * M_PI; vf = yf * M_PI; break; default: av_assert0(0); } break; case SEPARATE: // full range yf = 256.0f; uf = 256.0f; vf = 256.0f; break; default: av_assert0(0); } if (showspectrum->color_mode == CHANNEL) { if (showspectrum->nb_display_channels > 1) { uf *= 0.5 * sin((2 * M_PI * ch) / showspectrum->nb_display_channels); vf *= 0.5 * cos((2 * M_PI * ch) / showspectrum->nb_display_channels); } else { uf = 0.0f; vf = 0.0f; } } uf *= showspectrum->saturation; vf *= showspectrum->saturation; /* draw the channel */ for (y = 0; y < h; y++) { int row = (showspectrum->mode == COMBINED) ? y : ch * h + y; float *out = &showspectrum->combine_buffer[3 * row]; /* get magnitude */ float a = w * MAGNITUDE(y, ch); /* apply scale */ switch (showspectrum->scale) { case LINEAR: break; case SQRT: a = sqrt(a); break; case CBRT: a = cbrt(a); break; case LOG: a = 1 - log(FFMAX(FFMIN(1, a), 1e-6)) / log(1e-6); // zero = -120dBFS break; default: av_assert0(0); } if (showspectrum->color_mode == INTENSITY) { float y, u, v; int i; for (i = 1; i < sizeof(intensity_color_table) / sizeof(*intensity_color_table) - 1; i++) if (intensity_color_table[i].a >= a) break; // i now is the first item >= the color // now we know to interpolate between item i - 1 and i if (a <= intensity_color_table[i - 1].a) { y = intensity_color_table[i - 1].y; u = intensity_color_table[i - 1].u; v = intensity_color_table[i - 1].v; } else if (a >= intensity_color_table[i].a) { y = intensity_color_table[i].y; u = intensity_color_table[i].u; v = intensity_color_table[i].v; } else { float start = intensity_color_table[i - 1].a; float end = intensity_color_table[i].a; float lerpfrac = (a - start) / (end - start); y = intensity_color_table[i - 1].y * (1.0f - lerpfrac) + intensity_color_table[i].y * lerpfrac; u = intensity_color_table[i - 1].u * (1.0f - lerpfrac) + intensity_color_table[i].u * lerpfrac; v = intensity_color_table[i - 1].v * (1.0f - lerpfrac) + intensity_color_table[i].v * lerpfrac; } out[0] += y * yf; out[1] += u * uf; out[2] += v * vf; } else { out[0] += a * yf; out[1] += a * uf; out[2] += a * vf; } } } /* copy to output */ if (showspectrum->sliding) { for (plane = 0; plane < 3; plane++) { for (y = 0; y < outlink->h; y++) { uint8_t *p = outpicref->data[plane] + y * outpicref->linesize[plane]; memmove(p, p + 1, outlink->w - 1); } } showspectrum->xpos = outlink->w - 1; } for (plane = 0; plane < 3; plane++) { uint8_t *p = outpicref->data[plane] + (outlink->h - 1) * outpicref->linesize[plane] + showspectrum->xpos; for (y = 0; y < outlink->h; y++) { *p = rint(FFMAX(0, FFMIN(showspectrum->combine_buffer[3 * y + plane], 255))); p -= outpicref->linesize[plane]; } } outpicref->pts = insamples->pts + av_rescale_q(showspectrum->consumed, (AVRational){ 1, inlink->sample_rate }, outlink->time_base); push_frame(outlink); } return add_samples; } static int filter_frame(AVFilterLink *inlink, AVFilterBufferRef *insamples) { AVFilterContext *ctx = inlink->dst; ShowSpectrumContext *showspectrum = ctx->priv; int left_samples = insamples->audio->nb_samples; showspectrum->consumed = 0; while (left_samples) { const int added_samples = plot_spectrum_column(inlink, insamples, left_samples); showspectrum->consumed += added_samples; left_samples -= added_samples; } avfilter_unref_buffer(insamples); return 0; } static const AVFilterPad showspectrum_inputs[] = { { .name = "default", .type = AVMEDIA_TYPE_AUDIO, .filter_frame = filter_frame, .min_perms = AV_PERM_READ, }, { NULL } }; static const AVFilterPad showspectrum_outputs[] = { { .name = "default", .type = AVMEDIA_TYPE_VIDEO, .config_props = config_output, .request_frame = request_frame, }, { NULL } }; AVFilter avfilter_avf_showspectrum = { .name = "showspectrum", .description = NULL_IF_CONFIG_SMALL("Convert input audio to a spectrum video output."), .init = init, .uninit = uninit, .query_formats = query_formats, .priv_size = sizeof(ShowSpectrumContext), .inputs = showspectrum_inputs, .outputs = showspectrum_outputs, .priv_class = &showspectrum_class, };