圖片的按比例縮放

+(UIImage* )scaleImage:(UIImage* )image toSize:(float )scaleSize{

    

    UIGraphicsBeginImageContext(CGSizeMake(image.size.width*scaleSize, image.size.height));

    [image drawInRect:CGRectMake(0, image.size.height*(scaleSize*0.5), image.size.width*scaleSize, image.size.height*scaleSize)];  //此處是寬，高同時縮放    比例按實際要求來

    UIImage* scaledImage =UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndPDFContext();

    return scaledImage;

}