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elseif ass_r_a:find("^&H%x%x%x%x%x%x%x%x$") then    -- ASS color+alpha (style)

elseif ass_r_a:find("^&H%x%x%x%x%x%x%x%x&$") then   -- ASS color+alpha (style)

        coloralpha = function(ass_a_r, g, b, a)
            -- result: a, r, g, b, ass_complete, ass_color, ass_alpha
            local result = { a = nil, r = nil, g = nil, b = nil, ass = nil, ass_c = nil, ass_a = nil }

            g = g and g or false -- set g explicit to false if it not given
            if g then -- g is given, with this b should be given too
                a = a and a or false -- set a explicit to false if it not given
                if a then -- a r g b in numbers is given
                    r = ass_a_r
                else -- r g b in numbers is given
                    r = ass_a_r
                    a = 255
                end
            else -- just ass_a_r is given
                if type(ass_a_r) == "string" then -- ass value is given
                    if ass_a_r:find("^&H%x%x&$") then -- ass alpha is given
                        a = 255 - tonumber(ass_a_r:sub(3,4), 16)
                        r, g, b = 0, 0, 0
                    elseif ass_a_r:find("^&H%x%x%x%x%x%x&$") then -- ass r g b is given
                        a = 255
                        r = tonumber(ass_a_r:sub(7,8), 16)
                        g = tonumber(ass_a_r:sub(5,6), 16)
                        b = tonumber(ass_a_r:sub(3,4), 16)
                    elseif ass_a_r:find("^&H%x%x%x%x%x%x%x%x&$") then -- ass r g b a is given
                        a = 255 - tonumber(ass_a_r:sub(3,4), 16)
                        r = tonumber(ass_a_r:sub(9,10), 16) 
                        g = tonumber(ass_a_r:sub(7,8), 16) 
                        b = tonumber(ass_a_r:sub(5,6), 16)
                    else
                        error(string.format("invalid string %q", ass_a_r))
                    end
                else -- alpha in number is given
                    a = ass_a_r
                    r, g, b = 0, 0, 0
                end
            end

            result.a, result.r, result.g, result.b = a, r, g, b
            result.ass = string.format("&H%02X%02X%02X%02X&", 255 - a, b, g, r)
            result.ass_r = string.format("&H%02X%02X%02X&", b, g, r)
            result.ass_a = string.format("&H%02X&", 255 - a)

            return unpack(result)
        end,