local magick = "/usr/local/ImageMagick/bin/magick"
local tmp = io.open(magick,"r")
if tmp == nil then
    -- in mac os
    magick = "/usr/local/bin/magick"
else
    io.close(tmp)
end
print(magick)

--local origin = {
--    "/Users/moicen/Music/alchemy/Song-of-joy.png",
--    "/Users/moicen/Music/alchemy/You-and-me.png"
--}
--origin = table.concat(origin, " ")
--ngx.log(ngx.ERR, origin)
--local file = io.popen("/usr/local/bin/magick convert -append " .. origin .. " /tmp/combined.jpeg" )
--local output = file:read("*all")
--file:close()
--ngx.say(output)