Hi 

I tried to filters out some videos. I used gst_link_filtered, and gst_element_linkpads_filtered to filter out videos with a wrong resolution. However, the filter works fine using raw video formats, but always returns true when using mpeg4 videos. 
example: here the filter caps creation 

GstCaps	*caps = gst_caps_new_simple ("video/mpeg",
                                     "width", G_TYPE_INT, 384,
                                     "height", G_TYPE_INT, 288,
                                     "mpegversion", G_TYPE_INT, 4,
                                     NULL);

the video source caps: 
video/mpeg, mpegversion=(int)4, systemstream=(boolean)false, profile=(string)simple, width=(int)1920, height=(int)1080, framerate=(fraction)30/1, pixel-aspect-ratio=(fraction)1/1

assertions:
gst_element_link_filtered (src, dest, caps)
gst_element_link_pads_filtered (src, NULL, dest, NULL, caps)

both return TRUE.

According to resolution, they should not.

Look into the source code: gstpad.c, and 
gst_pad_link_prepare returns GST_PAD_LINK_OK, I  think it should not.
I see that there is a "fixme" in the function.