iOS11及以上 保存拍照的图片都会进行自动旋转处理,在上传图片时可通过图片格式判断获取图片类型,并重新调整方向,调整方向的分类代码如下: ,但会出现HEIC转jpeg(转jpeg是因为pc端也要浏览该图片), 占用内存变大的现象.
- (UIImage*)fixOrientation {
// No-op if the orientation is already correct
if (self.imageOrientation == UIImageOrientationUp) return self;
// We need to calculate the proper transformation to make the image upright.
// We do it in 2 steps: Rotate if Left/Right/Down, and then flip if Mirrored.
CGAffineTransform transform = CGAffineTransformIdentity;
switch (self.imageOrientation) {
case UIImageOrientationDown:
case UIImageOrientationDownMirrored:
transform =CGAffineTransformTranslate(transform,self.size.width,self.size.height);
transform =CGAffineTransformRotate(transform,M_PI);
break;
case UIImageOrientationLeft:
case UIImageOrientationLeftMirrored:
transform =CGAffineTransformTranslate(transform,self.size.width,0);
transform =CGAffineTransformRotate(transform,M_PI_2);
break;
case UIImageOrientationRight:
case UIImageOrientationRightMirrored:
transform =CGAffineTransformTranslate(transform,0,self.size.height);
transform =CGAffineTransformRotate(transform, -M_PI_2);
break;
}
switch (self.imageOrientation) {
case UIImageOrientationUpMirrored:
case UIImageOrientationDownMirrored:
transform =CGAffineTransformTranslate(transform,self.size.width,0);
transform =CGAffineTransformScale(transform, -1,1);
break;
case UIImageOrientationLeftMirrored:
case UIImageOrientationRightMirrored:
transform =CGAffineTransformTranslate(transform,self.size.height,0);
transform =CGAffineTransformScale(transform, -1,1);
break;
}
// Now we draw the underlying CGImage into a new context, applying the transform
// calculated above.
CGContextRef ctx = CGBitmapContextCreate(NULL, self.size.width, self.size.height,
CGImageGetBitsPerComponent(self.CGImage),0,
CGImageGetColorSpace(self.CGImage),
CGImageGetBitmapInfo(self.CGImage));
CGContextConcatCTM(ctx, transform);
switch (self.imageOrientation) {
case UIImageOrientationLeft:
case UIImageOrientationLeftMirrored:
case UIImageOrientationRight:
case UIImageOrientationRightMirrored:
// Grr...
CGContextDrawImage(ctx,CGRectMake(0,0,self.size.height,self.size.width),self.CGImage);
break;
default:
CGContextDrawImage(ctx,CGRectMake(0,0,self.size.width,self.size.height),self.CGImage);
break;
}
// And now we just create a new UIImage from the drawing context
CGImageRef cgimg = CGBitmapContextCreateImage(ctx);
UIImage*img = [UIImageimageWithCGImage:cgimg];
CGContextRelease(ctx);
CGImageRelease(cgimg);
returnimg;
}
