libavfilter/vsrc_buffer.c:119: error: Integer Overflow L2
  ([0, +oo] - 1):unsigned32 by call to `avfilter_unref_pic`.

libavfilter/vsrc_buffer.c:115:5: Assignment
113.     picref->pixel_aspect    = c->pixel_aspect;
114.     picref->interlaced      = c->frame.interlaced_frame;
115.     picref->top_field_first = c->frame.top_field_first;
         ^
116.     avfilter_start_frame(link, avfilter_ref_pic(picref, ~0));
117.     avfilter_draw_slice(link, 0, link->h, 1);

libavfilter/vsrc_buffer.c:117:5: Call
115.     picref->top_field_first = c->frame.top_field_first;
116.     avfilter_start_frame(link, avfilter_ref_pic(picref, ~0));
117.     avfilter_draw_slice(link, 0, link->h, 1);
         ^
118.     avfilter_end_frame(link);
119.     avfilter_unref_pic(picref);

libavfilter/avfilter.c:291:1: Parameter `link->cur_pic->linesize[*]`
  289. }
  290. 
  291. void avfilter_draw_slice(AVFilterLink *link, int y, int h, int slice_dir)
       ^
  292. {
  293.     uint8_t *src[4], *dst[4];

libavfilter/vsrc_buffer.c:119:5: Call
117.     avfilter_draw_slice(link, 0, link->h, 1);
118.     avfilter_end_frame(link);
119.     avfilter_unref_pic(picref);
         ^
120. 
121.     c->has_frame = 0;

libavfilter/avfilter.c:57:1: <LHS trace>
55. }
56. 
57. void avfilter_unref_pic(AVFilterPicRef *ref)
    ^
58. {
59.     if(!(--ref->pic->refcount))

libavfilter/avfilter.c:57:1: Parameter `ref->pic->refcount`
  55. }
  56. 
  57. void avfilter_unref_pic(AVFilterPicRef *ref)
      ^
  58. {
  59.     if(!(--ref->pic->refcount))

libavfilter/avfilter.c:59:10: Binary operation: ([0, +oo] - 1):unsigned32 by call to `avfilter_unref_pic` 
  57. void avfilter_unref_pic(AVFilterPicRef *ref)
  58. {
  59.     if(!(--ref->pic->refcount))
               ^
  60.         ref->pic->free(ref->pic);
  61.     av_free(ref);
