text: /*
   * 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/opt.h"
  #include "libavutil/time.h"
  #include "avfilter.h"
  #include "formats.h"
  #include "internal.h"
  
  enum BenchAction {
      ACTION_START,
      ACTION_STOP,
      NB_ACTION
  };
  
  typedef struct {
      const AVClass *class;
      int action;
      int64_t max, min;
      int64_t sum;
      int n;
  } BenchContext;
  
  #define OFFSET(x) offsetof(BenchContext, x)
  #define DEFINE_OPTIONS(filt_name, FLAGS)                                                                                \
  static const AVOption filt_name##_options[] = {                                                                         \
      { "action", "set action", OFFSET(action), AV_OPT_TYPE_INT, {.i64=ACTION_START}, 0, NB_ACTION-1, FLAGS, "action" },  \
          { "start", "start timer",  0, AV_OPT_TYPE_CONST, {.i64=ACTION_START}, INT_MIN, INT_MAX, FLAGS, "action" },      \
          { "stop",  "stop timer",   0, AV_OPT_TYPE_CONST, {.i64=ACTION_STOP},  INT_MIN, INT_MAX, FLAGS, "action" },      \
      { NULL }                                                                                                            \
  }
  
  #define START_TIME_KEY "lavfi.bench.start_time"
  #define T2F(v) ((v) / 1000000.)
  
  static av_cold int init(AVFilterContext *ctx)
  {
      BenchContext *s = ctx->priv;
      s->min = INT64_MAX;
      s->max = INT64_MIN;
      return 0;
  }
  
  static int filter_frame(AVFilterLink *inlink, AVFrame *in)
  {
      AVFilterContext *ctx = inlink->dst;
      BenchContext *s = ctx->priv;
      AVFilterLink *outlink = ctx->outputs[0];
      const int64_t t = av_gettime();
  
      if (t < 0)
          return ff_filter_frame(outlink, in);
  
      if (s->action == ACTION_START) {
          av_dict_set_int(&in->metadata, START_TIME_KEY, t, 0);
      } else if (s->action == ACTION_STOP) {
          AVDictionaryEntry *e = av_dict_get(in->metadata, START_TIME_KEY, NULL, 0);
          if (e) {
              const int64_t start = strtoll(e->value, NULL, 0);
              const int64_t diff = t - start;
              s->sum += diff;
              s->n++;
              s->min = FFMIN(s->min, diff);
              s->max = FFMAX(s->max, diff);
              av_log(s, AV_LOG_INFO, "t:%f avg:%f max:%f min:%f\n",
                     T2F(diff), T2F(s->sum / s->n), T2F(s->max), T2F(s->min));
          }
          av_dict_set(&in->metadata, START_TIME_KEY, NULL, 0);
      }
  
      return ff_filter_frame(outlink, in);
  }
  
  #if CONFIG_BENCH_FILTER
  DEFINE_OPTIONS(bench, AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM);
  AVFILTER_DEFINE_CLASS(bench);
  
  static const AVFilterPad bench_inputs[] = {
      {
          .name         = "default",
          .type         = AVMEDIA_TYPE_VIDEO,
          .filter_frame = filter_frame,
      },
      { NULL }
  };
  
  static const AVFilterPad bench_outputs[] = {
      {
          .name = "default",
          .type = AVMEDIA_TYPE_VIDEO,
      },
      { NULL }
  };
  
  AVFilter ff_vf_bench = {
      .name          = "bench",
      .description   = NULL_IF_CONFIG_SMALL("Benchmark part of a filtergraph."),
      .priv_size     = sizeof(BenchContext),
      .init          = init,
      .inputs        = bench_inputs,
      .outputs       = bench_outputs,
      .priv_class    = &bench_class,
  };
  #endif /* CONFIG_BENCH_FILTER */
  
  #if CONFIG_ABENCH_FILTER
  DEFINE_OPTIONS(abench, AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_AUDIO_PARAM);
  AVFILTER_DEFINE_CLASS(abench);
  
  static const AVFilterPad abench_inputs[] = {
      {
          .name         = "default",
          .type         = AVMEDIA_TYPE_AUDIO,
          .filter_frame = filter_frame,
      },
      { NULL }
  };
  
  static const AVFilterPad abench_outputs[] = {
      {
          .name = "default",
          .type = AVMEDIA_TYPE_AUDIO,
      },
      { NULL }
  };
  
  AVFilter ff_af_abench = {
      .name          = "abench",
      .description   = NULL_IF_CONFIG_SMALL("Benchmark part of a filtergraph."),
      .priv_size     = sizeof(BenchContext),
      .init          = init,
      .inputs        = abench_inputs,
      .outputs       = abench_outputs,
      .priv_class    = &abench_class,
  };
  #endif /* CONFIG_ABENCH_FILTER */
  