From c888adf590eeaf8f854de9067886ecb2f0f08419 Mon Sep 17 00:00:00 2001 From: Vladimir Panteleev Date: Fri, 8 Mar 2019 06:47:42 +0000 Subject: [PATCH] libavfilter: add photosensitivity filter --- Changelog | 1 + doc/filters.texi | 20 ++ libavfilter/Makefile | 1 + libavfilter/allfilters.c | 1 + libavfilter/version.h | 2 +- libavfilter/vf_photosensitivity.c | 336 ++++++++++++++++++++++++++++++ 6 files changed, 360 insertions(+), 1 deletion(-) create mode 100644 libavfilter/vf_photosensitivity.c diff --git a/Changelog b/Changelog index 743612cb91d..adecdaaf780 100644 --- a/Changelog +++ b/Changelog @@ -13,6 +13,7 @@ version : - streamhash muxer - sierpinski video source - scroll video filter +- photosensitivity filter version 4.2: diff --git a/doc/filters.texi b/doc/filters.texi index e7b3c8f88e6..b00787d2e86 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -14040,6 +14040,26 @@ Filter selects among @samp{t}, @samp{b} and @samp{p} using image analysis only. @end table @end table +@section photosensitivity +Reduce various flashes in video, so to help users with epilepsy. + +It accepts the following options: +@table @option +@item frames, f +Set how many frames to use when filtering. Default is 30. + +@item threshold, t +Set detection threshold factor. Default is 1. +Lower is stricter. + +@item skip +Set how many pixels to skip when sampling frames. Defalt is 1. +Allowed range is from 1 to 1024. + +@item bypass +Leave frames unchanged. Default is disabled. +@end table + @section pixdesctest Pixel format descriptor test filter, mainly useful for internal diff --git a/libavfilter/Makefile b/libavfilter/Makefile index 124a3496e65..182fe9df4be 100644 --- a/libavfilter/Makefile +++ b/libavfilter/Makefile @@ -321,6 +321,7 @@ OBJS-$(CONFIG_PALETTEUSE_FILTER) += vf_paletteuse.o framesync.o OBJS-$(CONFIG_PERMS_FILTER) += f_perms.o OBJS-$(CONFIG_PERSPECTIVE_FILTER) += vf_perspective.o OBJS-$(CONFIG_PHASE_FILTER) += vf_phase.o +OBJS-$(CONFIG_PHOTOSENSITIVITY_FILTER) += vf_photosensitivity.o OBJS-$(CONFIG_PIXDESCTEST_FILTER) += vf_pixdesctest.o OBJS-$(CONFIG_PIXSCOPE_FILTER) += vf_datascope.o OBJS-$(CONFIG_PP_FILTER) += vf_pp.o diff --git a/libavfilter/allfilters.c b/libavfilter/allfilters.c index 0408bcd3dfe..1a261290692 100644 --- a/libavfilter/allfilters.c +++ b/libavfilter/allfilters.c @@ -305,6 +305,7 @@ extern AVFilter ff_vf_paletteuse; extern AVFilter ff_vf_perms; extern AVFilter ff_vf_perspective; extern AVFilter ff_vf_phase; +extern AVFilter ff_vf_photosensitivity; extern AVFilter ff_vf_pixdesctest; extern AVFilter ff_vf_pixscope; extern AVFilter ff_vf_pp; diff --git a/libavfilter/version.h b/libavfilter/version.h index e51bab8261d..ad88845682f 100644 --- a/libavfilter/version.h +++ b/libavfilter/version.h @@ -30,7 +30,7 @@ #include "libavutil/version.h" #define LIBAVFILTER_VERSION_MAJOR 7 -#define LIBAVFILTER_VERSION_MINOR 60 +#define LIBAVFILTER_VERSION_MINOR 61 #define LIBAVFILTER_VERSION_MICRO 100 diff --git a/libavfilter/vf_photosensitivity.c b/libavfilter/vf_photosensitivity.c new file mode 100644 index 00000000000..4559454846a --- /dev/null +++ b/libavfilter/vf_photosensitivity.c @@ -0,0 +1,336 @@ +/* + * Copyright (c) 2019 Vladimir Panteleev + * + * 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 + +#include "libavutil/imgutils.h" +#include "libavutil/opt.h" +#include "libavutil/pixdesc.h" +#include "avfilter.h" + +#include "formats.h" +#include "internal.h" +#include "video.h" + +#define MAX_FRAMES 240 +#define GRID_SIZE 8 +#define NUM_CHANNELS 3 + +typedef struct PhotosensitivityFrame { + uint8_t grid[GRID_SIZE][GRID_SIZE][4]; +} PhotosensitivityFrame; + +typedef struct PhotosensitivityContext { + const AVClass *class; + + int nb_frames; + int skip; + float threshold_multiplier; + int bypass; + + int badness_threshold; + + /* Circular buffer */ + int history[MAX_FRAMES]; + int history_pos; + + PhotosensitivityFrame last_frame_e; + AVFrame *last_frame_av; +} PhotosensitivityContext; + +#define OFFSET(x) offsetof(PhotosensitivityContext, x) +#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM + +static const AVOption photosensitivity_options[] = { + { "frames", "set how many frames to use", OFFSET(nb_frames), AV_OPT_TYPE_INT, {.i64=30}, 2, MAX_FRAMES, FLAGS }, + { "f", "set how many frames to use", OFFSET(nb_frames), AV_OPT_TYPE_INT, {.i64=30}, 2, MAX_FRAMES, FLAGS }, + { "threshold", "set detection threshold factor (lower is stricter)", OFFSET(threshold_multiplier), AV_OPT_TYPE_FLOAT, {.dbl=1}, 0.1, FLT_MAX, FLAGS }, + { "t", "set detection threshold factor (lower is stricter)", OFFSET(threshold_multiplier), AV_OPT_TYPE_FLOAT, {.dbl=1}, 0.1, FLT_MAX, FLAGS }, + { "skip", "set pixels to skip when sampling frames", OFFSET(skip), AV_OPT_TYPE_INT, {.i64=1}, 1, 1024, FLAGS }, + { "bypass", "leave frames unchanged", OFFSET(bypass), AV_OPT_TYPE_BOOL, {.i64=0}, 0, 1, FLAGS }, + { NULL } +}; + +AVFILTER_DEFINE_CLASS(photosensitivity); + +static int query_formats(AVFilterContext *ctx) +{ + static const enum AVPixelFormat pixel_fmts[] = { + AV_PIX_FMT_RGB24, + AV_PIX_FMT_BGR24, + AV_PIX_FMT_NONE + }; + AVFilterFormats *formats = ff_make_format_list(pixel_fmts); + if (!formats) + return AVERROR(ENOMEM); + return ff_set_common_formats(ctx, formats); +} + +typedef struct ThreadData_convert_frame +{ + AVFrame *in; + PhotosensitivityFrame *out; + int skip; +} ThreadData_convert_frame; + +#define NUM_CELLS (GRID_SIZE * GRID_SIZE) + +static int convert_frame_partial(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs) +{ + int cell, gx, gy, x0, x1, y0, y1, x, y, c, area; + int sum[NUM_CHANNELS]; + const uint8_t *p; + + ThreadData_convert_frame *td = arg; + + const int slice_start = (NUM_CELLS * jobnr) / nb_jobs; + const int slice_end = (NUM_CELLS * (jobnr+1)) / nb_jobs; + + int width = td->in->width, height = td->in->height, linesize = td->in->linesize[0], skip = td->skip; + const uint8_t *data = td->in->data[0]; + + for (cell = slice_start; cell < slice_end; cell++) { + gx = cell % GRID_SIZE; + gy = cell / GRID_SIZE; + + x0 = width * gx / GRID_SIZE; + x1 = width * (gx+1) / GRID_SIZE; + y0 = height * gy / GRID_SIZE; + y1 = height * (gy+1) / GRID_SIZE; + + for (c = 0; c < NUM_CHANNELS; c++) { + sum[c] = 0; + } + for (y = y0; y < y1; y += skip) { + p = data + y * linesize + x0 * NUM_CHANNELS; + for (x = x0; x < x1; x += skip) { + //av_log(NULL, AV_LOG_VERBOSE, "%d %d %d : (%d,%d) (%d,%d) -> %d,%d | *%d\n", c, gx, gy, x0, y0, x1, y1, x, y, (int)row); + sum[0] += p[0]; + sum[1] += p[1]; + sum[2] += p[2]; + p += NUM_CHANNELS * skip; + // TODO: variable size + } + } + + area = ((x1 - x0 + skip - 1) / skip) * ((y1 - y0 + skip - 1) / skip); + for (c = 0; c < NUM_CHANNELS; c++) { + if (area) + sum[c] /= area; + td->out->grid[gy][gx][c] = sum[c]; + } + } + return 0; +} + +static void convert_frame(AVFilterContext *ctx, AVFrame *in, PhotosensitivityFrame *out, int skip) +{ + ThreadData_convert_frame td; + td.in = in; + td.out = out; + td.skip = skip; + ctx->internal->execute(ctx, convert_frame_partial, &td, NULL, FFMIN(NUM_CELLS, ff_filter_get_nb_threads(ctx))); +} + +typedef struct ThreadData_blend_frame +{ + AVFrame *target; + AVFrame *source; + uint16_t s_mul; +} ThreadData_blend_frame; + +static int blend_frame_partial(AVFilterContext *ctx, void *arg, int jobnr, int nb_jobs) +{ + int x, y; + uint8_t *t, *s; + + ThreadData_blend_frame *td = arg; + const uint16_t s_mul = td->s_mul; + const uint16_t t_mul = 0x100 - s_mul; + const int slice_start = (td->target->height * jobnr) / nb_jobs; + const int slice_end = (td->target->height * (jobnr+1)) / nb_jobs; + const int linesize = td->target->linesize[0]; + + for (y = slice_start; y < slice_end; y++) { + t = td->target->data[0] + y * td->target->linesize[0]; + s = td->source->data[0] + y * td->source->linesize[0]; + for (x = 0; x < linesize; x++) { + *t = (*t * t_mul + *s * s_mul) >> 8; + t++; s++; + } + } + return 0; +} + +static void blend_frame(AVFilterContext *ctx, AVFrame *target, AVFrame *source, float factor) +{ + ThreadData_blend_frame td; + td.target = target; + td.source = source; + td.s_mul = (uint16_t)(factor * 0x100); + ctx->internal->execute(ctx, blend_frame_partial, &td, NULL, FFMIN(ctx->outputs[0]->h, ff_filter_get_nb_threads(ctx))); +} + +static int get_badness(PhotosensitivityFrame *a, PhotosensitivityFrame *b) +{ + int badness, x, y, c; + badness = 0; + for (c = 0; c < NUM_CHANNELS; c++) { + for (y = 0; y < GRID_SIZE; y++) { + for (x = 0; x < GRID_SIZE; x++) { + badness += abs((int)a->grid[y][x][c] - (int)b->grid[y][x][c]); + //av_log(NULL, AV_LOG_VERBOSE, "%d - %d -> %d \n", a->grid[y][x], b->grid[y][x], badness); + //av_log(NULL, AV_LOG_VERBOSE, "%d -> %d \n", abs((int)a->grid[y][x] - (int)b->grid[y][x]), badness); + } + } + } + return badness; +} + +static int config_input(AVFilterLink *inlink) +{ + /* const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(inlink->format); */ + AVFilterContext *ctx = inlink->dst; + PhotosensitivityContext *s = ctx->priv; + + s->badness_threshold = (int)(GRID_SIZE * GRID_SIZE * 4 * 256 * s->nb_frames * s->threshold_multiplier / 128); + + return 0; +} + +static int filter_frame(AVFilterLink *inlink, AVFrame *in) +{ + int this_badness, current_badness, fixed_badness, new_badness, i, res; + PhotosensitivityFrame ef; + AVFrame *src, *out; + float factor; + AVDictionary **metadata; + + AVFilterContext *ctx = inlink->dst; + AVFilterLink *outlink = ctx->outputs[0]; + PhotosensitivityContext *s = ctx->priv; + + /* weighted moving average */ + current_badness = 0; + for (i = 1; i < s->nb_frames; i++) + current_badness += i * s->history[(s->history_pos + i) % s->nb_frames]; + current_badness /= s->nb_frames; + + convert_frame(ctx, in, &ef, s->skip); + this_badness = get_badness(&ef, &s->last_frame_e); + new_badness = current_badness + this_badness; + av_log(s, AV_LOG_VERBOSE, "badness: %6d -> %6d / %6d (%3d%% - %s)\n", + current_badness, new_badness, s->badness_threshold, + 100 * new_badness / s->badness_threshold, new_badness < s->badness_threshold ? "OK" : "EXCEEDED"); + + fixed_badness = new_badness; + if (new_badness < s->badness_threshold || !s->last_frame_av || s->bypass) { + factor = 1; /* for metadata */ + av_frame_free(&s->last_frame_av); + s->last_frame_av = src = in; + s->last_frame_e = ef; + s->history[s->history_pos] = this_badness; + } else { + factor = (float)(s->badness_threshold - current_badness) / (new_badness - current_badness); + if (factor <= 0) { + /* just duplicate the frame */ + s->history[s->history_pos] = 0; /* frame was duplicated, thus, delta is zero */ + } else { + res = av_frame_make_writable(s->last_frame_av); + if (res) { + av_frame_free(&in); + return res; + } + blend_frame(ctx, s->last_frame_av, in, factor); + + convert_frame(ctx, s->last_frame_av, &ef, s->skip); + this_badness = get_badness(&ef, &s->last_frame_e); + fixed_badness = current_badness + this_badness; + av_log(s, AV_LOG_VERBOSE, " fixed: %6d -> %6d / %6d (%3d%%) factor=%5.3f\n", + current_badness, fixed_badness, s->badness_threshold, + 100 * new_badness / s->badness_threshold, factor); + s->last_frame_e = ef; + s->history[s->history_pos] = this_badness; + } + src = s->last_frame_av; + } + s->history_pos = (s->history_pos + 1) % s->nb_frames; + + out = ff_get_video_buffer(outlink, in->width, in->height); + if (!out) { + av_frame_free(&in); + return AVERROR(ENOMEM); + } + av_frame_copy_props(out, in); + metadata = &out->metadata; + if (metadata) { + char value[128]; + + snprintf(value, sizeof(value), "%f", (float)new_badness / s->badness_threshold); + av_dict_set(metadata, "lavfi.photosensitivity.badness", value, 0); + + snprintf(value, sizeof(value), "%f", (float)fixed_badness / s->badness_threshold); + av_dict_set(metadata, "lavfi.photosensitivity.fixed-badness", value, 0); + + snprintf(value, sizeof(value), "%f", (float)this_badness / s->badness_threshold); + av_dict_set(metadata, "lavfi.photosensitivity.frame-badness", value, 0); + + snprintf(value, sizeof(value), "%f", factor); + av_dict_set(metadata, "lavfi.photosensitivity.factor", value, 0); + } + av_frame_copy(out, src); + return ff_filter_frame(outlink, out); +} + +static av_cold void uninit(AVFilterContext *ctx) +{ + PhotosensitivityContext *s = ctx->priv; + + av_frame_free(&s->last_frame_av); +} + +static const AVFilterPad inputs[] = { + { + .name = "default", + .type = AVMEDIA_TYPE_VIDEO, + .filter_frame = filter_frame, + .config_props = config_input, + }, + { NULL } +}; + +static const AVFilterPad outputs[] = { + { + .name = "default", + .type = AVMEDIA_TYPE_VIDEO, + }, + { NULL } +}; + +AVFilter ff_vf_photosensitivity = { + .name = "photosensitivity", + .description = NULL_IF_CONFIG_SMALL("Filter out photosensitive epilepsy seizure-inducing flashes."), + .priv_size = sizeof(PhotosensitivityContext), + .priv_class = &photosensitivity_class, + .uninit = uninit, + .query_formats = query_formats, + .inputs = inputs, + .outputs = outputs, +}; -- 2.39.2