[FFmpeg-devel] [PATCH 1/4] avfilter/vf_signalstats: Use 64bit for processing histogram

[Andreas Rheinhardt]

Andreas Rheinhardt:
> The result might not fit into 32bit if an image has gigantic
> dimensions and one of the planes has a dominant value
> (particularly so if said value is big).
> 
> Fixes Coverity issues #1598399, #1598401, #1598402, #1598403, #1598404.
> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
>  libavfilter/vf_signalstats.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/libavfilter/vf_signalstats.c b/libavfilter/vf_signalstats.c
> index 50c9df4298..78a23bb705 100644
> --- a/libavfilter/vf_signalstats.c
> +++ b/libavfilter/vf_signalstats.c
> @@ -721,10 +721,10 @@ static int filter_frame(AVFilterLink *link, AVFrame *in)
>          if (histv[fil])   maxv   = fil;
>          if (histsat[fil]) maxsat = fil;
>  
> -        toty   += histy[fil]   * fil;
> -        totu   += histu[fil]   * fil;
> -        totv   += histv[fil]   * fil;
> -        totsat += histsat[fil] * fil;
> +        toty   += (uint64_t)histy[fil]   * fil;
> +        totu   += (uint64_t)histu[fil]   * fil;
> +        totv   += (uint64_t)histv[fil]   * fil;
> +        totsat += (uint64_t)histsat[fil] * fil;
>  
>          accy   += histy[fil];
>          accu   += histu[fil];
> @@ -745,7 +745,7 @@ static int filter_frame(AVFilterLink *link, AVFrame *in)
>      maxhue = histhue[0];
>      medhue = -1;
>      for (fil = 0; fil < 360; fil++) {
> -        tothue += histhue[fil] * fil;
> +        tothue += (uint64_t)histhue[fil] * fil;
>          acchue += histhue[fil];
>  
>          if (medhue == -1 && acchue > s->cfs / 2)

Will apply this patchset tomorrow unless there are objections.

- Andreas