[FFmpeg-devel] [PATCH v2] avfilter/avf_showcqt: improve pts handling

wm4 nfxjfg at googlemail.com
Tue Feb 16 12:22:18 CET 2016


On Tue, 16 Feb 2016 18:01:16 +0700
Muhammad Faiz <mfcc64 at gmail.com> wrote:

> From bc59d4a7636e2f199b3dbda06e8e3bc53e260cae Mon Sep 17 00:00:00 2001
> From: Muhammad Faiz <mfcc64 at gmail.com>
> Date: Tue, 16 Feb 2016 07:03:37 +0700
> Subject: [PATCH v2] avfilter/avf_showcqt: improve pts handling
> 
> correct output pts based on input pts
> make seeking possible
> output frame one by one on eof
> tested with showinfo filter
> 
> Suggested-by: Paul B Mahol <onemda at gmail.com>
> ---
>  libavfilter/avf_showcqt.c | 47 +++++++++++++++++++++++++++++++++++------------
>  libavfilter/avf_showcqt.h |  2 +-
>  2 files changed, 36 insertions(+), 13 deletions(-)
> 
> diff --git a/libavfilter/avf_showcqt.c b/libavfilter/avf_showcqt.c
> index 712a999..6bb2d18 100644
> --- a/libavfilter/avf_showcqt.c
> +++ b/libavfilter/avf_showcqt.c
> @@ -48,6 +48,8 @@
>  #define FONTCOLOR       "st(0, (midi(f)-59.5)/12);" \
>      "st(1, if(between(ld(0),0,1), 0.5-0.5*cos(2*PI*ld(0)), 0));" \
>      "r(1-ld(1)) + b(ld(1))"
> +#define PTS_STEP 10
> +#define PTS_TOLERANCE 1
>  
>  #define OFFSET(x) offsetof(ShowCQTContext, x)
>  #define FLAGS (AV_OPT_FLAG_FILTERING_PARAM|AV_OPT_FLAG_VIDEO_PARAM)
> @@ -989,11 +991,10 @@ static void process_cqt(ShowCQTContext *s)
>          yuv_from_cqt(s->c_buf, s->cqt_result, s->sono_g, s->width);
>  }
>  
> -static int plot_cqt(AVFilterContext *ctx)
> +static int plot_cqt(AVFilterContext *ctx, AVFrame **frameout)
>  {
>      AVFilterLink *outlink = ctx->outputs[0];
>      ShowCQTContext *s = ctx->priv;
> -    int ret = 0;
>  
>      memcpy(s->fft_result, s->fft_data, s->fft_len * sizeof(*s->fft_data));
>      av_fft_permute(s->fft_ctx, s->fft_result);
> @@ -1004,7 +1005,7 @@ static int plot_cqt(AVFilterContext *ctx)
>      if (s->sono_h)
>          s->update_sono(s->sono_frame, s->c_buf, s->sono_idx);
>      if (!s->sono_count) {
> -        AVFrame *out = ff_get_video_buffer(outlink, outlink->w, outlink->h);
> +        AVFrame *out = *frameout = ff_get_video_buffer(outlink, outlink->w, outlink->h);
>          if (!out)
>              return AVERROR(ENOMEM);
>          if (s->bar_h)
> @@ -1013,14 +1014,13 @@ static int plot_cqt(AVFilterContext *ctx)
>              s->draw_axis(out, s->axis_frame, s->c_buf, s->bar_h);
>          if (s->sono_h)
>              s->draw_sono(out, s->sono_frame, s->bar_h + s->axis_h, s->sono_idx);
> -        out->pts = s->frame_count;
> -        ret = ff_filter_frame(outlink, out);
> -        s->frame_count++;
> +        out->pts = s->next_pts;
> +        s->next_pts += PTS_STEP;
>      }
>      s->sono_count = (s->sono_count + 1) % s->count;
>      if (s->sono_h)
>          s->sono_idx = (s->sono_idx + s->sono_h - 1) % s->sono_h;
> -    return ret;
> +    return 0;
>  }
>  
>  /* main filter control */
> @@ -1133,7 +1133,7 @@ static int config_output(AVFilterLink *outlink)
>      s->format = outlink->format;
>      outlink->sample_aspect_ratio = av_make_q(1, 1);
>      outlink->frame_rate = s->rate;
> -    outlink->time_base = av_inv_q(s->rate);
> +    outlink->time_base = av_mul_q(av_inv_q(s->rate), av_make_q(1, PTS_STEP));
>      av_log(ctx, AV_LOG_INFO, "video: %dx%d %s %d/%d fps, bar_h = %d, axis_h = %d, sono_h = %d.\n",
>             s->width, s->height, av_get_pix_fmt_name(s->format), s->rate.num, s->rate.den,
>             s->bar_h, s->axis_h, s->sono_h);
> @@ -1209,7 +1209,7 @@ static int config_output(AVFilterLink *outlink)
>          return AVERROR(ENOMEM);
>  
>      s->sono_count = 0;
> -    s->frame_count = 0;
> +    s->next_pts = 0;
>      s->sono_idx = 0;
>      s->remaining_fill = s->fft_len / 2;
>      s->remaining_frac = 0;
> @@ -1232,14 +1232,16 @@ static int config_output(AVFilterLink *outlink)
>  static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
>  {
>      AVFilterContext *ctx = inlink->dst;
> +    AVFilterLink *outlink = ctx->outputs[0];
>      ShowCQTContext *s = ctx->priv;
>      int remaining, step, ret, x, i, j, m;
>      float *audio_data;
> +    AVFrame *out = NULL;
>  
>      if (!insamples) {
>          while (s->remaining_fill < s->fft_len / 2) {
>              memset(&s->fft_data[s->fft_len - s->remaining_fill], 0, sizeof(*s->fft_data) * s->remaining_fill);
> -            ret = plot_cqt(ctx);
> +            ret = plot_cqt(ctx, &out);
>              if (ret < 0)
>                  return ret;
>  
> @@ -1248,6 +1250,9 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
>              for (x = 0; x < (s->fft_len-step); x++)
>                  s->fft_data[x] = s->fft_data[x+step];
>              s->remaining_fill += step;
> +
> +            if (out)
> +                return ff_filter_frame(outlink, out);
>          }
>          return AVERROR_EOF;
>      }
> @@ -1263,12 +1268,30 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *insamples)
>                  s->fft_data[j+m].re = audio_data[2*(i+m)];
>                  s->fft_data[j+m].im = audio_data[2*(i+m)+1];
>              }
> -            ret = plot_cqt(ctx);
> +            ret = plot_cqt(ctx, &out);
>              if (ret < 0) {
>                  av_frame_free(&insamples);
>                  return ret;
>              }
>              remaining -= s->remaining_fill;
> +            if (out) {
> +                int64_t pts = av_rescale_q(insamples->pts, inlink->time_base, av_make_q(1, inlink->sample_rate));
> +                pts += insamples->nb_samples - remaining - s->fft_len/2;
> +                pts = av_rescale_q(pts, av_make_q(1, inlink->sample_rate), outlink->time_base);
> +                if (FFABS(pts - out->pts) > PTS_TOLERANCE) {
> +                    av_log(ctx, AV_LOG_DEBUG, "changing pts from %"PRId64" (%.3f) to %"PRId64" (%.3f).\n",
> +                           out->pts, out->pts * av_q2d(outlink->time_base),
> +                           pts, pts * av_q2d(outlink->time_base));
> +                    out->pts = pts;
> +                    s->next_pts = pts + PTS_STEP;

What is this code needed for? The PTS_TOLERANCE thing specifically.

> +                }
> +                ret = ff_filter_frame(outlink, out);
> +                if (ret < 0) {
> +                    av_frame_free(&insamples);
> +                    return ret;
> +                }
> +                out = NULL;
> +            }
>              step = s->step + (s->step_frac.num + s->remaining_frac) / s->step_frac.den;
>              s->remaining_frac = (s->step_frac.num + s->remaining_frac) % s->step_frac.den;
>              for (m = 0; m < s->fft_len-step; m++)
> @@ -1294,7 +1317,7 @@ static int request_frame(AVFilterLink *outlink)
>  
>      ret = ff_request_frame(inlink);
>      if (ret == AVERROR_EOF)
> -        filter_frame(inlink, NULL);
> +        ret = filter_frame(inlink, NULL);
>      return ret;
>  }
>  
> diff --git a/libavfilter/avf_showcqt.h b/libavfilter/avf_showcqt.h
> index a48b2b0..39c9030 100644
> --- a/libavfilter/avf_showcqt.h
> +++ b/libavfilter/avf_showcqt.h
> @@ -60,7 +60,7 @@ typedef struct {
>      AVRational          step_frac;
>      int                 remaining_frac;
>      int                 remaining_fill;
> -    int64_t             frame_count;
> +    int64_t             next_pts;
>      double              *freq;
>      FFTContext          *fft_ctx;
>      Coeffs              *coeffs;



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