function resizeImage(obj) {
     var max_x = 250;//宽
     var max_y = 280;//高
     var x = "";
     var y = "";
   if(obj.width >= obj.height){
    if(obj.width >= max_x){
       x = obj.width / max_x;
       y = obj.height / x;
    }else{
       x = max_x / obj.width;
       y = x * obj.height;
    }
    obj.width = max_x;
    obj.height = y;
}else{
    if(obj.height >= max_y){
       x = obj.height / max_y;
       y = obj.width / x;
    }else{
       x = max_y / obj.height;
       y = x * obj.width;
    }
    obj.height = max_y;
    obj.width = y;
}
}

function resizeImage2(obj) {
     var max_x = 152;//宽
     var max_y = 200;//高
     var x = "";
     var y = "";
   if(obj.width >= obj.height){
    if(obj.width >= max_x){
       x = obj.width / max_x;
       y = obj.height / x;
    }else{
       x = max_x / obj.width;
       y = x * obj.height;
    }
    obj.width = max_x;
    obj.height = y;
}else{
    if(obj.height >= max_y){
       x = obj.height / max_y;
       y = obj.width / x;
    }else{
       x = max_y / obj.height;
       y = x * obj.width;
    }
    obj.height = max_y;
    obj.width = y;
}
}