GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavfilter/vf_blackdetect.c Lines: 0 61 0.0 %
Date: 2020-08-14 10:39:37 Branches: 0 20 0.0 %

Line Branch Exec Source
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/*
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 * Copyright (c) 2012 Stefano Sabatini
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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/**
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 * @file
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 * Video black detector, loosely based on blackframe with extended
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 * syntax and features
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 */
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#include <float.h>
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#include "libavutil/opt.h"
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#include "libavutil/timestamp.h"
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#include "avfilter.h"
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#include "internal.h"
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typedef struct BlackDetectContext {
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    const AVClass *class;
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    double  black_min_duration_time; ///< minimum duration of detected black, in seconds
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    int64_t black_min_duration;      ///< minimum duration of detected black, expressed in timebase units
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    int64_t black_start;             ///< pts start time of the first black picture
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    int64_t black_end;               ///< pts end time of the last black picture
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    int64_t last_picref_pts;         ///< pts of the last input picture
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    int black_started;
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    double       picture_black_ratio_th;
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    double       pixel_black_th;
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    unsigned int pixel_black_th_i;
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    unsigned int nb_black_pixels;   ///< number of black pixels counted so far
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} BlackDetectContext;
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#define OFFSET(x) offsetof(BlackDetectContext, x)
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#define FLAGS AV_OPT_FLAG_VIDEO_PARAM|AV_OPT_FLAG_FILTERING_PARAM
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static const AVOption blackdetect_options[] = {
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    { "d",                  "set minimum detected black duration in seconds", OFFSET(black_min_duration_time), AV_OPT_TYPE_DOUBLE, {.dbl=2}, 0, DBL_MAX, FLAGS },
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    { "black_min_duration", "set minimum detected black duration in seconds", OFFSET(black_min_duration_time), AV_OPT_TYPE_DOUBLE, {.dbl=2}, 0, DBL_MAX, FLAGS },
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    { "picture_black_ratio_th", "set the picture black ratio threshold", OFFSET(picture_black_ratio_th), AV_OPT_TYPE_DOUBLE, {.dbl=.98}, 0, 1, FLAGS },
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    { "pic_th",                 "set the picture black ratio threshold", OFFSET(picture_black_ratio_th), AV_OPT_TYPE_DOUBLE, {.dbl=.98}, 0, 1, FLAGS },
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    { "pixel_black_th", "set the pixel black threshold", OFFSET(pixel_black_th), AV_OPT_TYPE_DOUBLE, {.dbl=.10}, 0, 1, FLAGS },
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    { "pix_th",         "set the pixel black threshold", OFFSET(pixel_black_th), AV_OPT_TYPE_DOUBLE, {.dbl=.10}, 0, 1, FLAGS },
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    { NULL }
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};
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AVFILTER_DEFINE_CLASS(blackdetect);
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#define YUVJ_FORMATS \
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    AV_PIX_FMT_YUVJ411P, AV_PIX_FMT_YUVJ420P, AV_PIX_FMT_YUVJ422P, AV_PIX_FMT_YUVJ444P, AV_PIX_FMT_YUVJ440P
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static const enum AVPixelFormat yuvj_formats[] = {
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    YUVJ_FORMATS, AV_PIX_FMT_NONE
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};
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static int query_formats(AVFilterContext *ctx)
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{
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    static const enum AVPixelFormat pix_fmts[] = {
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        AV_PIX_FMT_GRAY8,
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        AV_PIX_FMT_YUV410P, AV_PIX_FMT_YUV411P,
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        AV_PIX_FMT_YUV420P, AV_PIX_FMT_YUV422P,
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        AV_PIX_FMT_YUV440P, AV_PIX_FMT_YUV444P,
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        AV_PIX_FMT_NV12, AV_PIX_FMT_NV21,
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        YUVJ_FORMATS,
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        AV_PIX_FMT_NONE
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    };
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    AVFilterFormats *fmts_list = ff_make_format_list(pix_fmts);
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    if (!fmts_list)
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        return AVERROR(ENOMEM);
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    return ff_set_common_formats(ctx, fmts_list);
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}
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static int config_input(AVFilterLink *inlink)
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{
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    AVFilterContext *ctx = inlink->dst;
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    BlackDetectContext *blackdetect = ctx->priv;
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    blackdetect->black_min_duration =
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        blackdetect->black_min_duration_time / av_q2d(inlink->time_base);
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    blackdetect->pixel_black_th_i = ff_fmt_is_in(inlink->format, yuvj_formats) ?
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        // luminance_minimum_value + pixel_black_th * luminance_range_size
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             blackdetect->pixel_black_th *  255 :
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        16 + blackdetect->pixel_black_th * (235 - 16);
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    av_log(blackdetect, AV_LOG_VERBOSE,
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           "black_min_duration:%s pixel_black_th:%f pixel_black_th_i:%d picture_black_ratio_th:%f\n",
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           av_ts2timestr(blackdetect->black_min_duration, &inlink->time_base),
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           blackdetect->pixel_black_th, blackdetect->pixel_black_th_i,
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           blackdetect->picture_black_ratio_th);
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    return 0;
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}
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static void check_black_end(AVFilterContext *ctx)
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{
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    BlackDetectContext *blackdetect = ctx->priv;
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    AVFilterLink *inlink = ctx->inputs[0];
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    if ((blackdetect->black_end - blackdetect->black_start) >= blackdetect->black_min_duration) {
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        av_log(blackdetect, AV_LOG_INFO,
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               "black_start:%s black_end:%s black_duration:%s\n",
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               av_ts2timestr(blackdetect->black_start, &inlink->time_base),
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               av_ts2timestr(blackdetect->black_end,   &inlink->time_base),
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               av_ts2timestr(blackdetect->black_end - blackdetect->black_start, &inlink->time_base));
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    }
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}
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static int request_frame(AVFilterLink *outlink)
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{
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    AVFilterContext *ctx = outlink->src;
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    BlackDetectContext *blackdetect = ctx->priv;
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    AVFilterLink *inlink = ctx->inputs[0];
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    int ret = ff_request_frame(inlink);
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    if (ret == AVERROR_EOF && blackdetect->black_started) {
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        // FIXME: black_end should be set to last_picref_pts + last_picref_duration
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        blackdetect->black_end = blackdetect->last_picref_pts;
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        check_black_end(ctx);
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    }
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    return ret;
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}
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static int filter_frame(AVFilterLink *inlink, AVFrame *picref)
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{
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    AVFilterContext *ctx = inlink->dst;
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    BlackDetectContext *blackdetect = ctx->priv;
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    double picture_black_ratio = 0;
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    const uint8_t *p = picref->data[0];
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    int x, i;
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    for (i = 0; i < inlink->h; i++) {
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        for (x = 0; x < inlink->w; x++)
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            blackdetect->nb_black_pixels += p[x] <= blackdetect->pixel_black_th_i;
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        p += picref->linesize[0];
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    }
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    picture_black_ratio = (double)blackdetect->nb_black_pixels / (inlink->w * inlink->h);
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    av_log(ctx, AV_LOG_DEBUG,
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           "frame:%"PRId64" picture_black_ratio:%f pts:%s t:%s type:%c\n",
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           inlink->frame_count_out, picture_black_ratio,
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           av_ts2str(picref->pts), av_ts2timestr(picref->pts, &inlink->time_base),
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           av_get_picture_type_char(picref->pict_type));
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    if (picture_black_ratio >= blackdetect->picture_black_ratio_th) {
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        if (!blackdetect->black_started) {
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            /* black starts here */
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            blackdetect->black_started = 1;
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            blackdetect->black_start = picref->pts;
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            av_dict_set(&picref->metadata, "lavfi.black_start",
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                av_ts2timestr(blackdetect->black_start, &inlink->time_base), 0);
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        }
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    } else if (blackdetect->black_started) {
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        /* black ends here */
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        blackdetect->black_started = 0;
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        blackdetect->black_end = picref->pts;
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        check_black_end(ctx);
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        av_dict_set(&picref->metadata, "lavfi.black_end",
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            av_ts2timestr(blackdetect->black_end, &inlink->time_base), 0);
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    }
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    blackdetect->last_picref_pts = picref->pts;
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    blackdetect->nb_black_pixels = 0;
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    return ff_filter_frame(inlink->dst->outputs[0], picref);
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}
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static const AVFilterPad blackdetect_inputs[] = {
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    {
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        .name          = "default",
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        .type          = AVMEDIA_TYPE_VIDEO,
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        .config_props  = config_input,
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        .filter_frame  = filter_frame,
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    },
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    { NULL }
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};
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static const AVFilterPad blackdetect_outputs[] = {
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    {
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        .name          = "default",
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        .type          = AVMEDIA_TYPE_VIDEO,
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        .request_frame = request_frame,
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    },
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    { NULL }
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};
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AVFilter ff_vf_blackdetect = {
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    .name          = "blackdetect",
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    .description   = NULL_IF_CONFIG_SMALL("Detect video intervals that are (almost) black."),
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    .priv_size     = sizeof(BlackDetectContext),
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    .query_formats = query_formats,
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    .inputs        = blackdetect_inputs,
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    .outputs       = blackdetect_outputs,
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    .priv_class    = &blackdetect_class,
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};