When a image is cropped from the center then crop image will take the aspect ratio of source image,But According to my requirement, aspect ratio will be change with new crop size.
I want to get exact center part of image with new aspect ratio.For example a large image is of size (320*480) then I want to crop center part of image of size (100,100) and aspect ratio will also be 100*100 ,No outer white or black part is required and image quality will be high.
Cropping function :
- (UIImage *)cropImage:(UIImage*)image andFrame:(CGRect)rect {
//Note : rec is nothing but the image frame which u want to crop exactly.
rect = CGRectMake(rect.origin.x*image.scale,
rect.origin.y*image.scale,
rect.size.width*image.scale,
rect.size.height*image.scale);
CGImageRef imageRef = CGImageCreateWithImageInRect([image CGImage], rect);
UIImage *result = [UIImage imageWithCGImage:imageRef
scale:image.scale
orientation:image.imageOrientation];
CGImageRelease(imageRef);
return result;
}
Please help me.
This might run
- (UIImage *)imageByCroppingImage:(UIImage *)image toSize:(CGSize)size
{
// not equivalent to image.size (which depends on the imageOrientation)!
double refWidth = CGImageGetWidth(image.CGImage);
double refHeight = CGImageGetHeight(image.CGImage);
double x = (refWidth - size.width) / 2.0;
double y = (refHeight - size.height) / 2.0;
CGRect cropRect = CGRectMake(x, y, size.height, size.width);
CGImageRef imageRef = CGImageCreateWithImageInRect([image CGImage], cropRect);
UIImage *cropped = [UIImage imageWithCGImage:imageRef scale:0.0 orientation:self.imageOrientation];
CGImageRelease(imageRef);
return cropped;
}
var imageView = UIImageView()
// height and width values corresponds to rectangle height and width
imageView = UIImageView(frame: CGRectMake(0, 0, width, height ))
imageView.image = UIImage(named: "Your Image Name")
// by setting content mode to .ScaleAspectFill image centrally fill in imageView. image might appear beyond image frame.
imageView.contentMode = .ScaleAspectFill
// by setting .clipsToBouds to true, image set to image frame.
imageView.clipsToBounds = true
view.addSubview(imageView)
// Work this code
-(UIImage *)croppedImage
{
UIImage *myImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
[self.bezierPath closePath];
CGContextSetRGBStrokeColor(UIGraphicsGetCurrentContext(), 0.0, 0.0, 0.0, 0.0);
_b_image = self.bg_imageview.image;
CGSize imageSize = _b_image.size;
CGRect imageRect = CGRectMake(0, 0, imageSize.width, imageSize.height);
UIGraphicsBeginImageContextWithOptions(imageSize, NO, [[UIScreen mainScreen] scale]);
[self.bezierPath addClip];
[_b_image drawInRect:imageRect];
UIImage *croppedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return croppedImage;
}
Calculate crop rect from image
float imgHeight = 100.0f; //Any according to requirement
float imgWidth = 100.0f; //Any according to requirement
CGRect cropRect = CGRectMake((largeImage.size.width/2)-(imgWidth/2),largeImage.size.height/2)-(imgHeight/2),imgWidth,imgHeight);
Now crop it
CGImageRef imageRef = CGImageCreateWithImageInRect([largeImage CGImage], cropRect);
// or use the UIImage wherever you like
UIImage *croppedImg = [UIImage imageWithCGImage:imageRef]];
CGImageRelease(imageRef);
Related
I have a fullscreen UIImageView with a image in it set to AspectFill (full bleed), how can I save only the visible portion of the image when its using the Aspect Fill content mode?
CGRect visibleRect;
visibleRect.size= mImageView.frame.size;
CGImageRef cropped_img = CGImageCreateWithImageInRect(mImageView.image.CGImage, visibleRect);
UIImage *finalImage = [[UIImage alloc]initWithCGImage:cropped_img];
UIImageWriteToSavedPhotosAlbum(finalImage, nil, nil, nil);
This is my current code, cropping and saving works, its just not cropping correctly. Any ideas?
Try this:
UIGraphicsBeginImageContext(mImageView.frame.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGImageRef image = CGBitmapContextCreateImage(context);
width = CGImageGetWidth(image);
height = CGImageGetHeight(image);
CGImageRef cropped_img = CGImageCreateWithImageInRect(image, CGRectMake(0, 0, width, height));
// save...
CGImageRelease(image);
UIGraphicsEndImageContext();
How can I crop my imageView into a bubble shape which I have the image in my project.
Following is simple code for resizing or crop image, you need to just pass height or width for image as you want:
For Get Croped Image:
UIImage *croppedImg = nil;
CGRect cropRect = CGRectMake(AS YOu Need);
croppedImg = [self croppIngimageByImageName:self.imageView.image toRect:cropRect];
Use following method that return UIImage (as You want size of image)
- (UIImage *)croppIngimageByImageName:(UIImage *)imageToCrop toRect:(CGRect)rect
{
//CGRect CropRect = CGRectMake(rect.origin.x, rect.origin.y, rect.size.width, rect.size.height+15);
CGImageRef imageRef = CGImageCreateWithImageInRect([imageToCrop CGImage], rect);
UIImage *cropped = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
return cropped;
}
Here you get Croped Image that return by above method;
OR RESIZING
And also Use following method for specific hight and width with image for Resizing UIImage:
+ (UIImage*)resizeImage:(UIImage*)image withWidth:(int)width withHeight:(int)height
{
CGSize newSize = CGSizeMake(width, height);
float widthRatio = newSize.width/image.size.width;
float heightRatio = newSize.height/image.size.height;
if(widthRatio > heightRatio)
{
newSize=CGSizeMake(image.size.width*heightRatio,image.size.height*heightRatio);
}
else
{
newSize=CGSizeMake(image.size.width*widthRatio,image.size.height*widthRatio);
}
UIGraphicsBeginImageContextWithOptions(newSize, NO, 0.0);
[image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
This method return NewImage, with specific size that you want.
I'm trying to crop a image into a square shape, and then scale it to a size 200x200. Here's the code I use, but it's not really working for me. The image I get is sometimes in a different orientation, or isn't cropped from the center, or is wider than it should be.
float scale = _avatar.image.scale;
UIImageOrientation orientation = _avatar.image.imageOrientation;
if(_avatar.image.size.width < _avatar.image.size.height){ // avatar is a UIImageView
float startingY = (_avatar.image.size.height-_avatar.image.size.width)/2; // image is taller, determine the origin of the width-sized square, which will be the new image
CGImageRef imageRef = CGImageCreateWithImageInRect([_avatar.image CGImage], CGRectMake(0, startingY, _avatar.image.size.width, _avatar.image.size.width));
_avatar.image = [UIImage imageWithCGImage:imageRef scale:scale orientation:orientation];
CGImageRelease(imageRef);
} else {
float startingX = (_avatar.image.size.width-_avatar.image.size.height)/2; // image is wider, determine the origin of the height-sized square, which will be the new image
CGImageRef imageRef = CGImageCreateWithImageInRect([_avatar.image CGImage], CGRectMake(startingX, 0, _avatar.image.size.height, _avatar.image.size.height));
_avatar.image = [UIImage imageWithCGImage:imageRef scale:scale orientation:orientation];
CGImageRelease(imageRef);
}
UIGraphicsBeginImageContextWithOptions(CGSizeMake(200, 200), YES, 0.0);
[_avatar.image drawInRect:CGRectMake(0, 0, 200, 200)];
UIImage *scaledImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
How it must be done to achieve the correct result?
I would suggest you to use this category for UIImage posted on github. They are also really simple classes and you can also use them to learn what is under the hood.
The UIImage has done all the coordinate and orientation tricks for you. So you should not use the width and height from an UIImage object to caculate the square's coordinate. You can take advantages of the UIKit to crop an image.
CGFloat startingX = 0;
CGFloat startingY = 0;
CGFloat squareWidth;
if(_avatar.image.size.width < _avatar.image.size.height){ // avatar is a UIImageView
startingY = (_avatar.image.size.height-_avatar.image.size.width)/2; // image is taller, determine the origin of the width-sized square, which will be the new image
squareWidth = _avatar.image.size.width;
} else {
startingX = (_avatar.image.size.width-_avatar.image.size.height)/2; // image is wider, determine the origin of the height-sized square, which will be the new image
squareWidth = _avatar.image.size.height;
}
UIGraphicsBeginImageContextWithOptions(CGSizeMake(squareWidth, squareWidth), YES, 0.0);
[_avatar.image drawAtPoint:CGPointMake(-startingX, -startingY)]; // Make an offset to draw part of the image
UIImage *croppedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIGraphicsBeginImageContextWithOptions(CGSizeMake(200, 200), YES, 0.0);
[croppedImage drawInRect:CGRectMake(0, 0, 200, 200)];
UIImage *scaledImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
I am creating an iPhone app which has image cropping feature. In this, I am getting the photos from the UIImagePickerController and passing it for cropping. There it has a scrollview and the selected image will be added as a subview to the scrollview. And I am using a UIButton for selecting the area for cropping. User can move the button over the imageview and place it anywhere, and when click on CROP button, the area similar to the frame size of the button should be cropped from the imageview.
I used the following code, but it is not returning the actual image.
CGRect clippedRect = CGRectMake(self.scrollView.frame.origin.x+90, self.scrollView.frame.origin.y, self.scrollView.frame.size.width-180, self.scrollView.frame.size.height-220);
CGImageRef imageRef = CGImageCreateWithImageInRect([self.myPhoto CGImage], clippedRect);
UIImage *newImage = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
self.imageView.image = newImage;
also used
- (UIImage *)cropImage:(UIImage *)oldImage {
CGSize imageSize = self.cropFrame.frame.size;
UIGraphicsBeginImageContextWithOptions( CGSizeMake( imageSize.width, imageSize.height), NO, 0.);
[oldImage drawAtPoint:CGPointMake( xPosition, yPosition)
blendMode:kCGBlendModeCopy
alpha:1.];
UIImage *croppedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return croppedImage;
}
but the result image is not the exact image as per the button frame. I am getting the image from another area.
Updated code
- (void)loadPhoto{
CGFloat w = self.myPhoto.size.width;
CGFloat h = self.myPhoto.size.height;
CGRect imageViewFrame = CGRectMake(0.0f, 0.0f, roundf(w / 2.0f), roundf(h / 2.0f));
self.scrollView.contentSize = imageViewFrame.size;
UIImageView *iv = [[UIImageView alloc] initWithFrame:imageViewFrame];
iv.contentMode = UIViewContentModeScaleAspectFit;
iv.image = self.myPhoto;
[self.view addSubview:iv];
self.imageView = iv;
[iv release];
}
CGRect crop;//= CGRectMake(10, 10, 360, 360);
crop.origin.x = self.cropFrame.frame.origin.x;
crop.origin.y = self.cropFrame.frame.origin.y;
crop.size.width = roundf(self.cropFrame.frame.size.width * 2.0f); //self.cropFrame.frame.size.width * 2;
crop.size.height = roundf(self.cropFrame.frame.size.height * 2.0f); //self.cropFrame.frame.size.height * 2;
NSLog(#"Rect: %#", NSStringFromCGRect(crop));
self.imageView.image = [self croppedImage:crop];
- (UIImage *)croppedImage:(CGRect)bounds {
CGImageRef imageRef = CGImageCreateWithImageInRect([self.imageView.image CGImage], bounds);
UIImage *croppedImage = [UIImage imageWithCGImage:imageRef scale:1.0 orientation:self.myPhoto.imageOrientation];
CGImageRelease(imageRef);
return croppedImage;
}
Please help to find a solution.
The iOS has a default feature for cropping images.Try this code.
picker.allowsEditing = YES;
and also check this controller for cropping..this is exactly the one you are looking for I think https://github.com/barrettj/BJImageCropper .Hope this helps you..
Since you are using a scrollView that allows the image to be scrolled, you need to adjust your crop rect to the scrollView's position:
float zoomScale = self.scrollView.zoomScale;
int cropX = (self.scrollView.contentOffset.x-imageView.frame.origin.x)/zoomScale;
int cropY = (self.scrollView.contentOffset.y-imageView.frame.origin.y)/zoomScale;
You could use this crop tool that I made. It essentially gives you an interface to allow the user to select the crop area. I think it is in line with that you are looking for.
https://github.com/nicholjs/BFCropInterface
Believing you have solve this problem. Me too had this when tried cropping functionality
Set image.size as the imageView.size & scrollView.contentSize. Below code will give the rect to crop
cropRect.origin = scrollView.contentOffset;
cropRect.size = scrollView.bounds.size;
cropRect.origin.x /= scrollView.zoomScale;
cropRect.origin.y /= scrollView.zoomScale;
cropRect.size.width /= scrollView.zoomScale;
cropRect.size.height /= scrollView.zoomScale;
If planning to show the full image first on visible rect. Setting the imageView.size & scrollView.contentSize to visible view size will give crop image of some other area. Instead try finding the zoom scale by
CGFloat dxWidth = viewCrop.frame.size.width / imageView.image.size.width;
CGFloat dxHeight = viewCrop.frame.size.height / imageView.image.size.height;
CGFloat zoomScale = fmaxf(dWidth, dHeight)
and apply (if by adding subView then after addSubView)
scrollView.minimumZoomScale = zoomScale; // to disable further zoom-out
[scrollView setZoomScale: zoomScale];
I am using the following code to convert the contents of a UIView to a PNG image:
UIGraphicsBeginImageContext(myView.bounds.size);
[myView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
This works fine. If the UIView is 500 pixels high, and I'd like to generate two images (one of the top half and one of the bottom half), how would I go about doing this?
Any help would be greatly appreciated.
There are a few ways you could do this. One way is to draw it into one big image, then make two sub-images:
static UIImage *halfOfImage(UIImage *fullImage, CGFloat yOffset) {
// Pass yOffset == 0 for the top half.
// Pass yOffset == 0.5 for the bottom half.
CGImageRef cgImage = fullImage.CGImage;
size_t width = CGImageGetWidth(cgImage);
size_t height = CGImageGetHeight(cgImage);
CGRect rect = CGRectMake(0, height * yOffset, width, height * 0.5f);
CGImageRef cgSubImage = CGImageCreateWithImageInRect(cgImage, rect);
UIImage *subImage = [UIImage imageWithCGImage:cgSubImage scale:fullImage.scale
orientation:fullImage.imageOrientation];
CGImageRelease(cgSubImage);
return subImage;
}
...
UIGraphicsBeginImageContext(myView.bounds.size);
[myView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImage *topHalfImage = halfOfImage(viewImage, 0);
UIImage *bottomHalfImage = halfOfImage(viewImage, 0.5f);