Add opencv stitching (panorama) element.

Submitted by Miguel Casas-Sanchez @miguelecasassanchez

Link to original bug (#719688)

Description

Created attachment 263303
Full patch containing panography element, mods to gstopencv.cpp and gsttemplatematch.cpp.

• Added a file that stitches together two video feeds - that supposedly overlap, and creates a single larger output panorama. Like panorama picture, for videos :)
  Multi pad input to one output synchro and glue code is copy-modified from gstdisparity.cpp :)
  From the doco:

• This element stitches two video feeds together, and represents the right
• channel as a reference over which the left one warps - supposed of course
• there is enough overlap for a correct feature matching.

• File gstopencv.c is changed to gstopencv.cpp, allowing for C++ (yei!) usage in gstpanography.{h,cpp}.

• File gsttemplatematch.{h,cpp}: renamed member |template| to |templatename|, clashed with C++ when included in gstopencv.cpp.

• Will upload some pics of how the output looks like.

Patch 263303, "Full patch containing panography element, mods to gstopencv.cpp and gsttemplatematch.cpp.":
gstpanography.0.patch

Version: 1.x