/* * Copyright (c) 2019 Paul B Mahol * * 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 <float.h> #include <math.h> #include "libavcodec/avfft.h" #include "libavutil/audio_fifo.h" #include "libavutil/avassert.h" #include "libavutil/channel_layout.h" #include "libavutil/opt.h" #include "libavutil/parseutils.h" #include "audio.h" #include "video.h" #include "avfilter.h" #include "filters.h" #include "internal.h" #include "window_func.h" typedef struct ShowSpatialContext { const AVClass *class; int w, h; AVRational frame_rate; FFTContext *fft[2]; ///< Fast Fourier Transform context FFTContext *ifft[2]; ///< Inverse Fast Fourier Transform context int fft_bits; ///< number of bits (FFT window size = 1<<fft_bits) FFTComplex *fft_data[2]; ///< bins holder for each (displayed) channels float *window_func_lut; ///< Window function LUT int win_func; int win_size; int buf_size; float overlap; int consumed; int hop_size; AVAudioFifo *fifo; int64_t pts; } ShowSpatialContext; #define OFFSET(x) offsetof(ShowSpatialContext, x) #define FLAGS AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM static const AVOption showspatial_options[] = { { "size", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "512x512"}, 0, 0, FLAGS }, { "s", "set video size", OFFSET(w), AV_OPT_TYPE_IMAGE_SIZE, {.str = "512x512"}, 0, 0, FLAGS }, { "win_size", "set window size", OFFSET(win_size), AV_OPT_TYPE_INT, {.i64 = 4096}, 1024, 65536, FLAGS }, WIN_FUNC_OPTION("win_func", OFFSET(win_func), FLAGS, WFUNC_HANNING), { "overlap", "set window overlap", OFFSET(overlap), AV_OPT_TYPE_FLOAT, {.dbl=0.5}, 0, 1, FLAGS }, { NULL } }; AVFILTER_DEFINE_CLASS(showspatial); static av_cold void uninit(AVFilterContext *ctx) { ShowSpatialContext *s = ctx->priv; int i; for (i = 0; i < 2; i++) av_fft_end(s->fft[i]); for (i = 0; i < 2; i++) av_fft_end(s->ifft[i]); for (i = 0; i < 2; i++) av_freep(&s->fft_data[i]); av_freep(&s->window_func_lut); av_audio_fifo_free(s->fifo); } static int query_formats(AVFilterContext *ctx) { AVFilterFormats *formats = NULL; AVFilterChannelLayouts *layout = NULL; AVFilterLink *inlink = ctx->inputs[0]; AVFilterLink *outlink = ctx->outputs[0]; static const enum AVSampleFormat sample_fmts[] = { AV_SAMPLE_FMT_FLTP, AV_SAMPLE_FMT_NONE }; static const enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_GBRP, AV_PIX_FMT_NONE }; int ret; formats = ff_make_format_list(sample_fmts); if ((ret = ff_formats_ref (formats, &inlink->outcfg.formats )) < 0 || (ret = ff_add_channel_layout (&layout, AV_CH_LAYOUT_STEREO )) < 0 || (ret = ff_channel_layouts_ref (layout , &inlink->outcfg.channel_layouts)) < 0) return ret; formats = ff_all_samplerates(); if ((ret = ff_formats_ref(formats, &inlink->outcfg.samplerates)) < 0) return ret; formats = ff_make_format_list(pix_fmts); if ((ret = ff_formats_ref(formats, &outlink->incfg.formats)) < 0) return ret; return 0; } static int run_channel_fft(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs) { ShowSpatialContext *s = ctx->priv; const float *window_func_lut = s->window_func_lut; AVFrame *fin = arg; const int ch = jobnr; const float *p = (float *)fin->extended_data[ch]; for (int n = 0; n < fin->nb_samples; n++) { s->fft_data[ch][n].re = p[n] * window_func_lut[n]; s->fft_data[ch][n].im = 0; } av_fft_permute(s->fft[ch], s->fft_data[ch]); av_fft_calc(s->fft[ch], s->fft_data[ch]); return 0; } static int config_output(AVFilterLink *outlink) { AVFilterContext *ctx = outlink->src; AVFilterLink *inlink = ctx->inputs[0]; ShowSpatialContext *s = ctx->priv; int i, fft_bits; float overlap; outlink->w = s->w; outlink->h = s->h; outlink->sample_aspect_ratio = (AVRational){1,1}; s->buf_size = 1 << av_log2(s->win_size); s->win_size = s->buf_size; fft_bits = av_log2(s->win_size); /* (re-)configuration if the video output changed (or first init) */ if (fft_bits != s->fft_bits) { s->fft_bits = fft_bits; /* FFT buffers: x2 for each 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 < 2; i++) { av_fft_end(s->fft[i]); av_freep(&s->fft_data[i]); } for (i = 0; i < 2; i++) { s->fft[i] = av_fft_init(fft_bits, 0); if (!s->fft[i]) { av_log(ctx, AV_LOG_ERROR, "Unable to create FFT context. " "The window size might be too high.\n"); return AVERROR(EINVAL); } } for (i = 0; i < 2; i++) { s->fft_data[i] = av_calloc(s->buf_size, sizeof(**s->fft_data)); if (!s->fft_data[i]) return AVERROR(ENOMEM); } /* pre-calc windowing function */ s->window_func_lut = av_realloc_f(s->window_func_lut, s->win_size, sizeof(*s->window_func_lut)); if (!s->window_func_lut) return AVERROR(ENOMEM); generate_window_func(s->window_func_lut, s->win_size, s->win_func, &overlap); if (s->overlap == 1) s->overlap = overlap; s->hop_size = (1.f - s->overlap) * s->win_size; if (s->hop_size < 1) { av_log(ctx, AV_LOG_ERROR, "overlap %f too big\n", s->overlap); return AVERROR(EINVAL); } } outlink->time_base = av_inv_q(outlink->frame_rate); av_audio_fifo_free(s->fifo); s->fifo = av_audio_fifo_alloc(inlink->format, inlink->channels, s->win_size); if (!s->fifo) return AVERROR(ENOMEM); return 0; } #define RE(y, ch) s->fft_data[ch][y].re #define IM(y, ch) s->fft_data[ch][y].im static void draw_dot(uint8_t *dst, int linesize, int value) { dst[0] = value; dst[1] = value; dst[-1] = value; dst[linesize] = value; dst[-linesize] = value; } static int draw_spatial(AVFilterLink *inlink, AVFrame *insamples) { AVFilterContext *ctx = inlink->dst; AVFilterLink *outlink = ctx->outputs[0]; ShowSpatialContext *s = ctx->priv; AVFrame *outpicref; int h = s->h - 2; int w = s->w - 2; int z = s->win_size / 2; outpicref = ff_get_video_buffer(outlink, outlink->w, outlink->h); if (!outpicref) return AVERROR(ENOMEM); outpicref->sample_aspect_ratio = (AVRational){1,1}; for (int i = 0; i < outlink->h; i++) { memset(outpicref->data[0] + i * outpicref->linesize[0], 0, outlink->w); memset(outpicref->data[1] + i * outpicref->linesize[1], 0, outlink->w); memset(outpicref->data[2] + i * outpicref->linesize[2], 0, outlink->w); } for (int j = 0; j < z; j++) { const int idx = z - 1 - j; float l = hypotf(RE(idx, 0), IM(idx, 0)); float r = hypotf(RE(idx, 1), IM(idx, 1)); float sum = l + r; float lp = atan2f(IM(idx, 0), RE(idx, 0)); float rp = atan2f(IM(idx, 1), RE(idx, 1)); float diffp = ((rp - lp) / (2.f * M_PI) + 1.f) * 0.5f; float diff = (sum < 0.000001f ? 0.f : (r - l) / sum) * 0.5f + 0.5f; float cr = av_clipf(cbrtf(l / sum), 0, 1) * 255.f; float cb = av_clipf(cbrtf(r / sum), 0, 1) * 255.f; float cg; int x, y; cg = diffp * 255.f; x = av_clip(w * diff, 0, w - 2) + 1; y = av_clip(h * diffp, 0, h - 2) + 1; draw_dot(outpicref->data[0] + outpicref->linesize[0] * y + x, outpicref->linesize[0], cg); draw_dot(outpicref->data[1] + outpicref->linesize[1] * y + x, outpicref->linesize[1], cb); draw_dot(outpicref->data[2] + outpicref->linesize[2] * y + x, outpicref->linesize[2], cr); } outpicref->pts = av_rescale_q(insamples->pts, inlink->time_base, outlink->time_base); return ff_filter_frame(outlink, outpicref); } static int spatial_activate(AVFilterContext *ctx) { AVFilterLink *inlink = ctx->inputs[0]; AVFilterLink *outlink = ctx->outputs[0]; ShowSpatialContext *s = ctx->priv; int ret; FF_FILTER_FORWARD_STATUS_BACK(outlink, inlink); if (av_audio_fifo_size(s->fifo) < s->win_size) { AVFrame *frame = NULL; ret = ff_inlink_consume_frame(inlink, &frame); if (ret < 0) return ret; if (ret > 0) { s->pts = frame->pts; s->consumed = 0; av_audio_fifo_write(s->fifo, (void **)frame->extended_data, frame->nb_samples); av_frame_free(&frame); } } if (av_audio_fifo_size(s->fifo) >= s->win_size) { AVFrame *fin = ff_get_audio_buffer(inlink, s->win_size); if (!fin) return AVERROR(ENOMEM); fin->pts = s->pts + s->consumed; s->consumed += s->hop_size; ret = av_audio_fifo_peek(s->fifo, (void **)fin->extended_data, FFMIN(s->win_size, av_audio_fifo_size(s->fifo))); if (ret < 0) { av_frame_free(&fin); return ret; } av_assert0(fin->nb_samples == s->win_size); ff_filter_execute(ctx, run_channel_fft, fin, NULL, 2); ret = draw_spatial(inlink, fin); av_frame_free(&fin); av_audio_fifo_drain(s->fifo, s->hop_size); if (ret <= 0) return ret; } FF_FILTER_FORWARD_STATUS(inlink, outlink); if (ff_outlink_frame_wanted(outlink) && av_audio_fifo_size(s->fifo) < s->win_size) { ff_inlink_request_frame(inlink); return 0; } if (av_audio_fifo_size(s->fifo) >= s->win_size) { ff_filter_set_ready(ctx, 10); return 0; } return FFERROR_NOT_READY; } static const AVFilterPad showspatial_inputs[] = { { .name = "default", .type = AVMEDIA_TYPE_AUDIO, }, }; static const AVFilterPad showspatial_outputs[] = { { .name = "default", .type = AVMEDIA_TYPE_VIDEO, .config_props = config_output, }, }; const AVFilter ff_avf_showspatial = { .name = "showspatial", .description = NULL_IF_CONFIG_SMALL("Convert input audio to a spatial video output."), .uninit = uninit, .priv_size = sizeof(ShowSpatialContext), FILTER_INPUTS(showspatial_inputs), FILTER_OUTPUTS(showspatial_outputs), FILTER_QUERY_FUNC(query_formats), .activate = spatial_activate, .priv_class = &showspatial_class, .flags = AVFILTER_FLAG_SLICE_THREADS, };