iOS图片压缩

/**

 *  调整图片尺寸和大小

 *

 *  @param source_Image  原始图片

 *

 *  @param maxSize      新图片最大存储大小,单位为KB

 *

 *  @return 新图片imageData

 */

- (NSData *)resetSizeOfImageData:(UIImage *)source_image maxSize:(NSInteger)maxSize

{

    //先调整分辨率

    CGSize newSize = CGSizeMake(source_image.size.width, source_image.size.height);

    CGFloat tempHeight = newSize.height / 1024;

    CGFloat tempWidth = newSize.width / 1024;

    if (tempWidth > 1.0 && tempWidth > tempHeight) {

        newSize = CGSizeMake(source_image.size.width / tempWidth, source_image.size.height / tempWidth);

    }

    else if (tempHeight > 1.0 && tempWidth < tempHeight){

        newSize = CGSizeMake(source_image.size.width / tempHeight, source_image.size.height / tempHeight);

    }

    UIGraphicsBeginImageContext(newSize);

    [source_image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];

    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();

    UIGraphicsEndImageContext();

    //调整大小

    NSData *imageData = UIImageJPEGRepresentation(newImage,1.0);

    NSUInteger sizeOrigin = [imageData length];

    NSUInteger sizeOriginKB = sizeOrigin / 1024;

    if (sizeOriginKB > maxSize) {

        NSData *finallImageData = UIImageJPEGRepresentation(newImage,0.50);

        return finallImageData;

    }

    return imageData;

}