UIImageJPEGRepresentation和UIImagePNGRepresentation都很慢

Question

在这里，我将我的图像转换为二进制数据的类别在UIImage上有静态method.My问题是UIImageJPEGRepresentation和UIImagePNGRepresentation是非常缓慢的6秒。我需要1秒的解决方案。任何人都可以帮助我。 在这里，我将我的图像传递给类别方法，直到它的大小减小到小于或等于10kbs。

-(NSData *)imageConvertToBinary :(UIImage *) image{ 

     NSLog(@"Image Convert "); 

     //UIImagePNGRepresentation(image); 
     NSData *imageData = UIImageJPEGRepresentation(image, .000032); 
     NSLog(@"Image Done "); 

     //Change size of image to 10kbs 

     int size = imageData.length; 
     NSLog(@"SIZE OF IMAGE:First %i ", size); 
     NSData *data = UIImageJPEGRepresentation(image, .0032); 
     NSLog(@"Start while "); 
     int temp=0; 
     while (data.length/1000 >= 10) { 
      image = [UIImage imageWithImage:image andWidth:image.size.width/2 andHeight:image.size.height/2]; 

      data = UIImageJPEGRepresentation(image, .0032); 
      temp++; 
      NSLog(@"temp %u",temp); 

     } 

     size = data.length; 
     NSLog(@"SIZE OF IMAGE:after %i ", size); 


     return data; 

    } 

and also i have category class on UIImage 
@implementation UIImage (ImageProcessing) 

+(UIImage*)imageWithImage:(UIImage*)image andWidth:(CGFloat)width andHeight:(CGFloat)height 
{ 
    UIGraphicsBeginImageContext(CGSizeMake(width, height)); 
    [image drawInRect:CGRectMake(0,0,width,height)]; 
    UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext(); 
    UIGraphicsEndImageContext(); 

    return newImage; 
} 
@end 

---

的NSData *数据; 必须等于什么

Answer 1

我减少你使用更两次UIImageJPEGRepresentation试试这个

- (NSData *)imageConvertToBinary :(UIImage *) image{ 
    NSData *data ; 
    NSLog(@"Start while "); 
    int temp=0; 
    while (data.length/1000 >= 10) { 
     image = [UIImage imageWithImage:image andWidth:image.size.width/2 andHeight:image.size.height/2]; 
     data = UIImageJPEGRepresentation(image, .0032); 
     temp++; 
     NSLog(@"temp %u",temp); 
    } 
    NSLog(@"End while "); 
    int size = data.length; 
    NSLog(@"SIZE OF IMAGE:after %i ", size); 
    return data; 
}