lavfi: print key-frame and picture type information in ff_dlog_ref()

Signed-off-by: NStefano Sabatini <stefano.sabatini-lala@poste.it>
(cherry picked from commit f7bdffb0)

libavfilter/avfilter.c

@@ -237,11 +237,13 @@ static void ff_dlog_ref(void *ctx, AVFilterBufferRef *ref, int end)
             ref->pts, ref->pos);
 
     if (ref->video) {
-        av_dlog(ctx, " a:%d/%d s:%dx%d i:%c",
+        av_dlog(ctx, " a:%d/%d s:%dx%d i:%c iskey:%d type:%c",
                 ref->video->pixel_aspect.num, ref->video->pixel_aspect.den,
                 ref->video->w, ref->video->h,
                 !ref->video->interlaced     ? 'P' :         /* Progressive  */
-                ref->video->top_field_first ? 'T' : 'B');   /* Top / Bottom */
+                ref->video->top_field_first ? 'T' : 'B',    /* Top / Bottom */
+                ref->video->key_frame,
+                av_get_picture_type_char(ref->video->pict_type));
     }
     if (ref->audio) {
         av_dlog(ctx, " cl:%"PRId64"d sn:%d s:%d sr:%d p:%d",