avfilter/drawbox+drawgrid - add option to prevent overwriting of source pixels
authorGyan Doshi <gyandoshi@gmail.com>
Mon, 11 Dec 2017 17:05:18 +0000 (22:35 +0530)
committerLou Logan <lou@lrcd.com>
Thu, 14 Dec 2017 22:44:45 +0000 (13:44 -0900)
commit1c76134fe37ac20695627e3f5ce1f2bbf1245fcc
tree3db7109fea202a62e3d53231db89ce904070af86
parent980af9a88cfd743d71fad67e7dd905231ea0a4f7
avfilter/drawbox+drawgrid - add option to prevent overwriting of source pixels

If the user-supplied color in drawbox and drawgrid filters is non-opaque,
the box & grid painting overwrites the input's pixels (including alpha).
Users typically expect the alpha of the specified color to only act as a key
for compositing on top of the main input.

Added option allows users to select between replacement and composition.
Tested and documented.
doc/filters.texi
libavfilter/vf_drawbox.c