前段时间处理了下图片上传压缩的问题，在这里记录下。iPhone拍摄的照片2-3M可压缩至30-60KB左右，清晰度还可以接受,如果一次处理多张高清图，放入子线程中进行压缩
/**
* 图片上传压缩
* @param source_image 原图片
* @param compressQuality 压缩系数 0-1
* 默认参考大小30kb,一般用该方法可达到要求，压缩系数可根据压缩后的清晰度权衡，项目里我用的0.2😆
*/
+ (NSData *)resetSizeOfImageData:(UIImage *)source_image compressQuality:(CGFloat)compressQuality
{
return [self resetSizeOfImageData:source_image referenceSize:30 compressQuality:compressQuality];
}
/**
* 图片上传压缩
* @param source_image 原图片
* @param referenceSize 上传的参考大小**KB
* @param compressQuality 压缩系数 0-1
* @return imageData
*/
+ (NSData *)resetSizeOfImageData:(UIImage *)source_image referenceSize:(NSInteger)maxSize compressQuality:(CGFloat)compressQuality
{
//先调整分辨率
CGSize newSize = CGSizeMake(source_image.size.width, source_image.size.height);
NSInteger tempHeight = newSize.height / 1024;
NSInteger 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,compressQuality);
return finallImageData;
}
return imageData;
}
