更新:
在 iPhone OS 3.0+ 中,整个 UIImagePickerController API 发生了变化。这个问题和答案应该考虑2.2。遗留代码。
<小时/>当使用 UIImagePickerController 并且您允许编辑图像时。 iPhone 允许用户调整图像大小和平移图像。但是,编辑图像的最大尺寸上限为 320x320。
作为示例,我拍摄了一张 iPhone 屏幕截图并将其放入照片库中,该图片库的大小为 480x320 png。当我使用 UIImagePickerController 选择该图像时,即使我不缩放或平移图像,它也会在从 UIImagePickerController 返回之前被裁剪为 320x320。但是,如果我关闭编辑,图像将返回正确的 480x320 尺寸。
我的理论: iPhone 非常巧妙地显示了 2 个覆盖在图像上的非标准半透明工具栏。这些工具栏在照片上留下了一个无害的 320x320“窗口”。在我看来,这个窗口有效地剪辑了底层照片。
注意: 回调还返回一个包含原始图像和剪切矩形的编辑字典,但当然该矩形的最大尺寸也是 320x320。
关于如何允许缩放和平移大于 320x320 的图像有什么想法吗?
一些代码:
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)img editingInfo:(NSDictionary *)editInfo {
self.myImageView.userInteractionEnabled=YES;
CGRect imageFrame = myImageView.frame;
CGPoint imageCenter = myImageView.center;
imageFrame.size = img.size;
myImageView.frame = imageFrame;
self.myImageView.image = img;
myImageView.center = imageCenter;
[self dismissModalViewControllerAnimated:YES];
[self performSelector:@selector(hideToolBars) withObject:nil afterDelay:2.0];
}
最佳答案
正如克雷格所说,这是开发论坛和苹果常规讨论板上的一个问题。然而,我确实找到了解决方法。我使用的一些代码来自:
这包括您需要的大部分内容,并解决所有相机方向问题。我添加了以下内容,它将接收编辑信息并使用它来获取带有此添加的原始裁剪矩形:
- (UIImage*)scaleImage:(UIImage*)anImage withEditingInfo:(NSDictionary*)editInfo{
UIImage *newImage;
UIImage *originalImage = [editInfo valueForKey:@"UIImagePickerControllerOriginalImage"];
CGSize originalSize = CGSizeMake(originalImage.size.width, originalImage.size.height);
CGRect originalFrame;
originalFrame.origin = CGPointMake(0,0);
originalFrame.size = originalSize;
CGRect croppingRect = [[editInfo valueForKey:@"UIImagePickerControllerCropRect"] CGRectValue];
CGSize croppingRectSize = CGSizeMake(croppingRect.size.width, croppingRect.size.height);
CGSize croppedScaledImageSize = anImage.size;
float scaledBarClipHeight = 80;
CGSize scaledImageSize;
float scale;
if(!CGSizeEqualToSize(croppedScaledImageSize, originalSize)){
scale = croppedScaledImageSize.width/croppingRectSize.width;
float barClipHeight = scaledBarClipHeight/scale;
croppingRect.origin.y -= barClipHeight;
croppingRect.size.height += (2*barClipHeight);
if(croppingRect.origin.y<=0){
croppingRect.size.height += croppingRect.origin.y;
croppingRect.origin.y=0;
}
if(croppingRect.size.height > (originalSize.height - croppingRect.origin.y)){
croppingRect.size.height = (originalSize.height - croppingRect.origin.y);
}
scaledImageSize = croppingRect.size;
scaledImageSize.width *= scale;
scaledImageSize.height *= scale;
newImage = [self cropImage:originalImage to:croppingRect andScaleTo:scaledImageSize];
}else{
newImage = originalImage;
}
return newImage;
}
我将开发论坛帖子中的回调方法更新为以下内容:
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)img editingInfo:(NSDictionary *)editInfo {
[self dismissModalViewControllerAnimated:YES];
self.myImageView.userInteractionEnabled=YES;
CGRect imageFrame = myImageView.frame;
CGPoint imageCenter = myImageView.center;
UIImage *croppedImage;
NSMutableDictionary *imageDescriptor = [editInfo mutableCopy];
// CGFloat scaleSize = 400.0f;
CGFloat scaleSize = 640.0f;
switch ([picker sourceType]) {
//done
case UIImagePickerControllerSourceTypePhotoLibrary:
croppedImage = [self scaleImage:img withEditingInfo:editInfo];
[imageDescriptor setObject:croppedImage forKey:@"croppedImage"];
break;
case UIImagePickerControllerSourceTypeCamera: {
UIImageOrientation originalOrientation = [[editInfo objectForKey:UIImagePickerControllerOriginalImage] imageOrientation];
if (originalOrientation != UIImageOrientationUp) {
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
CGRect origRect;
[[editInfo objectForKey:UIImagePickerControllerCropRect] getValue:&origRect];
UIImage *rotatedImage = straightenAndScaleImage([editInfo objectForKey:UIImagePickerControllerOriginalImage], scaleSize);
CGFloat scale = scaleSize/1600.0f;
origRect.origin.x *= scale;
origRect.origin.y *= scale;
origRect.size.width *= scale;
origRect.size.height *= scale;
croppedImage = [self cropImage:rotatedImage to:origRect andScaleTo:CGSizeMake(320, 480)];
[imageDescriptor setObject:croppedImage forKey:@"croppedImage"];
[pool drain];
}
else {
croppedImage = [self scaleImage:img withEditingInfo:editInfo];
[imageDescriptor setObject:croppedImage forKey:@"croppedImage"];
}
}
break;
case UIImagePickerControllerSourceTypeSavedPhotosAlbum: {
UIImageOrientation originalOrientation = [[editInfo objectForKey:UIImagePickerControllerOriginalImage] imageOrientation];
if (originalOrientation != UIImageOrientationUp) {
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
CGRect origRect;
[[editInfo objectForKey:UIImagePickerControllerCropRect] getValue:&origRect];
UIImage *rotatedImage = straightenAndScaleImage([editInfo objectForKey:UIImagePickerControllerOriginalImage], scaleSize);
CGFloat scale = scaleSize/640.0f;
origRect.origin.x *= scale;
origRect.origin.y *= scale;
origRect.size.width *= scale;
origRect.size.height *= scale;
croppedImage = [self cropImage:rotatedImage to:origRect andScaleTo:CGSizeMake(320, 480)];
[imageDescriptor setObject:croppedImage forKey:@"croppedImage"];
[pool drain];
}
else {
croppedImage = [self scaleImage:img withEditingInfo:editInfo];
[imageDescriptor setObject:croppedImage forKey:@"croppedImage"];
}
}
break;
default:
break;
}
imageFrame.size = croppedImage.size;
myImageView.frame = imageFrame;
myImageView.image = [imageDescriptor objectForKey:@"croppedImage"];
myImageView.center = imageCenter;
}
关于iphone - UIImagePickerController 编辑允许将 UIImage 锁定为最大尺寸 320x320,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/724092/