function?outval?=?avg_gradient（img）?
%?OUTVAL?=?AVG_GRADIENT（IMG）?
?
if?nargin?==?1?
????img?=?double（img）;?
????%?Get?the?size?of?img?
????[rcb]?=?size（img）;?
?????
????dx?=?1;?
????dy?=?1;?
????for?k?=?1?:?b?
????????band?=?img（::k）;?
????????[dzdxdzdy]?=?gradient（banddxdy）;?
????????s?=?sqrt（（dzdx?.^?2?+?dzdy?.^2）?./?2）;?
????????g（k）?=?sum（sum（s））?/?（（r?-?1）?*?（c?-?1））;?
????end?
????outval?=?mean（g）;?
else?
????error（‘Wrong?number?of?input!‘）;?
end

?屬性????????????大小?????日期????時間???名稱
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?????文件????????485??2009-10-02?10:10??圖像質量評價\avg_gradient.m

?????文件????????621??2009-10-02?10:10??圖像質量評價\edge_intensity.m

?????文件???????1017??2009-10-02?10:11??圖像質量評價\shannon.m

?????文件????????240??2009-10-02?10:11??圖像質量評價\variance.m

?????目錄??????????0??2009-10-02?10:14??圖像質量評價

-----------?---------??----------?-----??----

?????????????????2363????????????????????5