The　analysis　of　the　influence　of　the　thresholds　and　Gauss　filter　on　edge　closure　in　contraditional　Canny　algorithm　is　presented.　Firstly　image　was　filtered　of　eight　directions　of　the　current　pixel　replaced　the　Gauss　filter,　there　is　no　over-smoothing　pixels　in　Gradient　image;　Secondly,　combined　maximized　cross　entropy　criterion　with　the　relative　artificial　intelligence　theory　to　obtain　the　high　and　low　thresholds.　The　adaptive　filter　was　to　setup　models　in　the　eight　directions　around　the　processing　pixel,　then　defined　template　that　will　be　used　according　to　minimized　variance　in　the　neighborhood　of　the　current　pixel,　the　gray　value　was　replaced　by　the　mean　value　of　the　template　which　had　minimized　variance,　then　obtained　smoothed　image.　Experiments　proved　that　this　algorithm　may　obtain　higher　low-threshold　and　lower　high-threshold,　and　not　only　avoided　the　introduction　of　pseudo-edge　but　also　detected　more　edge　pixels　as　soon　as　possible,　and　meantime　it　has　strong　anti-noise　performance.