Need help with background change

[becuk]

Good evening. I have few (1000-2000) images like this (http://petromi.com/get/h1f4Ixf176a2c0668e11) with pink(partial) backgound. Need change pink background to white. Who can give advice, how do it in imagemagick. Thanks.

[fmw42]

try something like this


convert h1f4Ixf176a2c0668e11.png \
\( -clone 0 -channel red -separate +channel \) \
\( -clone 1 -level 0x50% \) -compose over -composite result.png