无需调整大小即可压缩图像质量

Question

我想压缩图像质量而不重新调整尺寸。我已经经历了许多与压缩和重新调整大小相关的帖子，但我没有得到我正在寻找的确切内容。我正在使用此代码：

- (UIImage *)compressImage:(UIImage *)image withCompressionFactor:(int)compressionFactor
    {
      double factor = 1.0;
      double adjustment = 1.0/ sqrt(2.0);
      CGSize size = image.size;
      CGSize currentSize = size;
      UIImage *currentImage = image;
      NSData *imageData;
     int requiredLength;

      imageData = UIImagePNGRepresentation(image);

     requiredLength = imageData.length/compressionFactor; // (compressionfactor = 3)

     while( imageData.length >= requiredLength)
     {
      factor *= adjustment;
  currentSize = CGSizeMake(roundf(size.width * factor), roundf(size.height *   factor));
    currentImage = [image resizedImage:currentSize interpolationQuality:0.1]; 
        imageData = UIImagePNGRepresentation(currentImage);
  }

return currentImage;
}

在这种情况下，由于重新调整大小，我的图像大小和图像质量正在降低。有没有办法压缩图像质量而不重新调整尺寸？任何提示或解决方案？