[FFmpeg-devel] [PATCH 2/4] vf_ssim: fix s->coefs for yuv with non-4:2:0 subsampling.

Ronald S. Bultje rsbultje at gmail.com
Sun Jul 12 14:18:48 CEST 2015


Hi,

On Sun, Jul 12, 2015 at 6:54 AM, Paul B Mahol <onemda at gmail.com> wrote:

> Dana 12. 7. 2015. 01:56 osoba "Ronald S. Bultje" <rsbultje at gmail.com>
> napisala je:
> >
> > ---
> >  libavfilter/vf_ssim.c | 81
> +++++++++++++++++++++++----------------------------
> >  1 file changed, 37 insertions(+), 44 deletions(-)
> >
> > diff --git a/libavfilter/vf_ssim.c b/libavfilter/vf_ssim.c
> > index 3ef122f..b1c3368 100644
> > --- a/libavfilter/vf_ssim.c
> > +++ b/libavfilter/vf_ssim.c
> > @@ -34,6 +34,7 @@
> >   * Caculate the SSIM between two input videos.
> >   */
> >
> > +#include "libavutil/avstring.h"
> >  #include "libavutil/opt.h"
> >  #include "libavutil/pixdesc.h"
> >  #include "avfilter.h"
> > @@ -50,13 +51,14 @@ typedef struct SSIMContext {
> >      char *stats_file_str;
> >      int nb_components;
> >      uint64_t nb_frames;
> > -    double ssim[4];
> > +    double ssim[4], ssim_total;
> >      char comps[4];
> > -    int *coefs;
> > +    float coefs[4];
> >      uint8_t rgba_map[4];
> >      int planewidth[4];
> >      int planeheight[4];
> >      int *temp;
> > +    int is_rgb;
> >  } SSIMContext;
> >
> >  #define OFFSET(x) offsetof(SSIMContext, x)
> > @@ -70,10 +72,6 @@ static const AVOption ssim_options[] = {
> >
> >  AVFILTER_DEFINE_CLASS(ssim);
> >
> > -static const int rgb_coefs[4]  = { 1, 1, 1, 3};
> > -static const int yuv_coefs[4]  = { 4, 1, 1, 6};
> > -static const int gray_coefs[4] = { 1, 0, 0, 1};
> > -
> >  static void set_meta(AVDictionary **metadata, const char *key, char
> comp, float d)
> >  {
> >      char value[128];
> > @@ -185,37 +183,38 @@ static AVFrame *do_ssim(AVFilterContext *ctx,
> AVFrame *main,
> >  {
> >      AVDictionary **metadata = avpriv_frame_get_metadatap(main);
> >      SSIMContext *s = ctx->priv;
> > -    float c[4], ssimv;
> > +    float c[4], ssimv = 0.0;
> >      int i;
> >
> >      s->nb_frames++;
> >
> > -    for (i = 0; i < s->nb_components; i++)
> > +    for (i = 0; i < s->nb_components; i++) {
> >          c[i] = ssim_plane(main->data[i], main->linesize[i],
> >                            ref->data[i], ref->linesize[i],
> >                            s->planewidth[i], s->planeheight[i], s->temp);
> > -
> > -    ssimv = (c[0] * s->coefs[0] + c[1] * s->coefs[1] + c[2] *
> s->coefs[2]) / s->coefs[3];
> > -
> > -    for (i = 0; i < s->nb_components; i++)
> > -        set_meta(metadata, "lavfi.ssim.", s->comps[i], c[i]);
> > +        ssimv += s->coefs[i] * c[i];
> > +        s->ssim[i] += c[i];
> > +    }
> > +    for (i = 0; i < s->nb_components; i++) {
> > +        int cidx = s->is_rgb ? s->rgba_map[i] : i;
> > +        set_meta(metadata, "lavfi.ssim.", s->comps[i], c[cidx]);
> > +    }
> > +    s->ssim_total += ssimv;
> >
> >      set_meta(metadata, "lavfi.ssim.All", 0, ssimv);
> > -    set_meta(metadata, "lavfi.ssim.dB", 0, ssim_db(c[0] * s->coefs[0] +
> c[1] * s->coefs[1] + c[2] * s->coefs[2], s->coefs[3]));
> > +    set_meta(metadata, "lavfi.ssim.dB", 0, ssim_db(ssimv, 1.0));
> >
> >      if (s->stats_file) {
> >          fprintf(s->stats_file, "n:%"PRId64" ", s->nb_frames);
> >
> > -        for (i = 0; i < s->nb_components; i++)
> > -            fprintf(s->stats_file, "%c:%f ", s->comps[i], c[i]);
> > +        for (i = 0; i < s->nb_components; i++) {
> > +            int cidx = s->is_rgb ? s->rgba_map[i] : i;
> > +            fprintf(s->stats_file, "%c:%f ", s->comps[i], c[cidx]);
> > +        }
> >
> > -        fprintf(s->stats_file, "All:%f (%f)\n", ssimv, ssim_db(c[0] *
> s->coefs[0] + c[1] * s->coefs[1] + c[2] * s->coefs[2], s->coefs[3]));
> > +        fprintf(s->stats_file, "All:%f (%f)\n", ssimv, ssim_db(ssimv,
> 1.0));
> >      }
> >
> > -    s->ssim[0] += c[0];
> > -    s->ssim[1] += c[1];
> > -    s->ssim[2] += c[2];
> > -
> >      return main;
> >  }
> >
> > @@ -264,7 +263,7 @@ static int config_input_ref(AVFilterLink *inlink)
> >      const AVPixFmtDescriptor *desc =
> av_pix_fmt_desc_get(inlink->format);
> >      AVFilterContext *ctx  = inlink->dst;
> >      SSIMContext *s = ctx->priv;
> > -    int is_rgb;
> > +    int sum = 0, i;
> >
> >      s->nb_components = desc->nb_components;
> >
> > @@ -278,24 +277,20 @@ static int config_input_ref(AVFilterLink *inlink)
> >          return AVERROR(EINVAL);
> >      }
> >
> > -    is_rgb = ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0;
> > -    s->comps[0] = is_rgb ? 'R' : 'Y';
> > -    s->comps[1] = is_rgb ? 'G' : 'U';
> > -    s->comps[2] = is_rgb ? 'B' : 'V';
> > +    s->is_rgb = ff_fill_rgba_map(s->rgba_map, inlink->format) >= 0;
> > +    s->comps[0] = s->is_rgb ? 'R' : 'Y';
> > +    s->comps[1] = s->is_rgb ? 'G' : 'U';
> > +    s->comps[2] = s->is_rgb ? 'B' : 'V';
> >      s->comps[3] = 'A';
> >
> > -    if (is_rgb) {
> > -        s->coefs = rgb_coefs;
> > -    } else if (s->nb_components == 1) {
> > -        s->coefs = gray_coefs;
> > -    } else {
> > -        s->coefs = yuv_coefs;
> > -    }
> > -
> >      s->planeheight[1] = s->planeheight[2] = FF_CEIL_RSHIFT(inlink->h,
> desc->log2_chroma_h);
> >      s->planeheight[0] = s->planeheight[3] = inlink->h;
> >      s->planewidth[1]  = s->planewidth[2]  = FF_CEIL_RSHIFT(inlink->w,
> desc->log2_chroma_w);
> >      s->planewidth[0]  = s->planewidth[3]  = inlink->w;
> > +    for (i = 0; i < s->nb_components; i++)
> > +        sum += s->planeheight[i] * s->planewidth[i];
> > +    for (i = 0; i < s->nb_components; i++)
> > +        s->coefs[i] = (double) s->planeheight[i] * s->planewidth[i] /
> sum;
> >
> >      s->temp = av_malloc((2 * inlink->w + 12) * sizeof(*s->temp));
> >      if (!s->temp)
> > @@ -340,17 +335,15 @@ static av_cold void uninit(AVFilterContext *ctx)
> >      SSIMContext *s = ctx->priv;
> >
> >      if (s->nb_frames > 0) {
> > -        if (s->nb_components == 3) {
> > -            av_log(ctx, AV_LOG_INFO, "SSIM %c:%f %c:%f %c:%f All:%f
> (%f)\n",
> > -               s->comps[0], s->ssim[0] / s->nb_frames,
> > -               s->comps[1], s->ssim[1] / s->nb_frames,
> > -               s->comps[2], s->ssim[2] / s->nb_frames,
> > -               (s->ssim[0] * 4 + s->ssim[1] + s->ssim[2]) /
> (s->nb_frames * 6),
> > -               ssim_db(s->ssim[0] * 4 + s->ssim[1] + s->ssim[2],
> s->nb_frames * 6));
> > -        } else if (s->nb_components == 1) {
> > -            av_log(ctx, AV_LOG_INFO, "SSIM All:%f (%f)\n",
> > -               s->ssim[0] / s->nb_frames, ssim_db(s->ssim[0],
> s->nb_frames));
> > +        char buf[256];
> > +        int i;
> > +        buf[0] = 0;
> > +        for (i = 0; i < s->nb_components; i++) {
> > +            int c = s->is_rgb ? s->rgba_map[i] : i;
> > +            av_strlcatf(buf, sizeof(buf), " %c:%f", s->comps[i],
> s->ssim[c] / s->nb_frames);
> >          }
> > +        av_log(ctx, AV_LOG_INFO, "SSIM%s All:%f (%f)\n", buf,
> > +               s->ssim_total / s->nb_frames, ssim_db(s->ssim_total,
> s->nb_frames));
> >      }
> >
> >      ff_dualinput_uninit(&s->dinput);
> > --
> > 2.1.2
> >
> >
>
> Should be ok if ssim results are same before and after this patch for 420p
> case.


They are identical.

Ronald


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