libavfilter/avfilter.c:290: error: Integer Overflow L2
  ([0, +oo] - 1):unsigned32 by call to `avfilter_unref_pic`.

libavfilter/avfilter.c:290:9: Call
288.      * a copied version dues to permission issues */
289.     if(link->srcpic) {
290.         avfilter_unref_pic(link->srcpic);
             ^
291.         link->srcpic = NULL;
292.     }

libavfilter/avfilter.c:56:1: <LHS trace>
54. }
55. 
56. void avfilter_unref_pic(AVFilterPicRef *ref)
    ^
57. {
58.     if(!(--ref->pic->refcount))

libavfilter/avfilter.c:56:1: Parameter `ref->pic->refcount`
  54. }
  55. 
  56. void avfilter_unref_pic(AVFilterPicRef *ref)
      ^
  57. {
  58.     if(!(--ref->pic->refcount))

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

void avfilter_unref_pic(AVFilterPicRef *ref)
{
    if(!(--ref->pic->refcount))
        ref->pic->free(ref->pic);
    av_free(ref);
}
['void avfilter_end_frame(AVFilterLink *link)\n{\n    void (*end_frame)(AVFilterLink *);\n    if(!(end_frame = link_dpad(link).end_frame))\n        end_frame = avfilter_default_end_frame;\n    end_frame(link);\n    if(link->srcpic) {\n        avfilter_unref_pic(link->srcpic);\n        link->srcpic = NULL;\n    }\n}', 'void avfilter_unref_pic(AVFilterPicRef *ref)\n{\n    if(!(--ref->pic->refcount))\n        ref->pic->free(ref->pic);\n    av_free(ref);\n}']