diff --git a/doc/filters.texi b/doc/filters.texi index bc37e667e0..32720dba41 100644 --- a/doc/filters.texi +++ b/doc/filters.texi @@ -10430,6 +10430,9 @@ expression, and vice versa. The default value of @var{x} and @var{y} is 0. +If @var{x} or @var{y} evaluate to a negative number, they'll be changed +so the input image is centered on the padded area. + @item color Specify the color of the padded area. For the syntax of this option, check the "Color" section in the ffmpeg-utils manual. diff --git a/libavfilter/vf_pad.c b/libavfilter/vf_pad.c index 44a8fec0cb..725dc29e96 100644 --- a/libavfilter/vf_pad.c +++ b/libavfilter/vf_pad.c @@ -173,8 +173,13 @@ static int config_input(AVFilterLink *inlink) goto eval_fail; s->x = var_values[VAR_X] = res; + if (s->x < 0 || s->x + inlink->w > s->w) + s->x = var_values[VAR_X] = (s->w - inlink->w) / 2; + if (s->y < 0 || s->y + inlink->h > s->h) + s->y = var_values[VAR_Y] = (s->h - inlink->h) / 2; + /* sanity check params */ - if (s->w < 0 || s->h < 0 || s->x < 0 || s->y < 0) { + if (s->w < 0 || s->h < 0) { av_log(ctx, AV_LOG_ERROR, "Negative values are not acceptable.\n"); return AVERROR(EINVAL); } @@ -192,10 +197,7 @@ static int config_input(AVFilterLink *inlink) inlink->w, inlink->h, s->w, s->h, s->x, s->y, s->rgba_color[0], s->rgba_color[1], s->rgba_color[2], s->rgba_color[3]); - if (s->x < 0 || s->y < 0 || - s->w <= 0 || s->h <= 0 || - (unsigned)s->x + (unsigned)inlink->w > s->w || - (unsigned)s->y + (unsigned)inlink->h > s->h) { + if (s->w <= 0 || s->h <= 0) { av_log(ctx, AV_LOG_ERROR, "Input area %d:%d:%d:%d not within the padded area 0:0:%d:%d or zero-sized\n", s->x, s->y, s->x + inlink->w, s->y + inlink->h, s->w, s->h);