I have method that zooming UIImage
- (UIImage*)croppedImageWithImage:(UIImage *)image zoom:(CGFloat)zoom
{
CGFloat zoomReciprocal = 1.0f / zoom;
CGPoint offset = CGPointMake(40, 40);
CGRect croppedRect = CGRectMake(offset.x, offset.y, image.size.width * zoomReciprocal, image.size.height * zoomReciprocal);
CGImageRef croppedImageRef = CGImageCreateWithImageInRect([image CGImage], croppedRect);
UIImage* croppedImage = [[UIImage alloc] initWithCGImage:croppedImageRef scale:[image scale] orientation:[image imageOrientation]];
CGImageRelease(croppedImageRef);
return croppedImage;
}
How to save image width and height after zooming?
To save zoomed image :
UIImageWriteToSavedPhotosAlbum(croppedImage, nil, nil, nil);
To save Image Size
CGSize imageSize = CGSizeMake(croppedImage.size.width, croppedImage.size.height);
If you want to save the image width and height just create CGSize variable and save like below
CGSize croppedSize = croppedImage.size
Related
I am using the following crop method to crop a uiimage that's sitting in a UIImageView which is then sitting in a UIScrollView.
-(UIImage *)cropImage:(UIImage *)image
{
float scale = 1.0f/_scrollView.zoomScale;
NSLog(#"Oh and heres that zoomScale: %f", _scrollView.zoomScale);
CGRect visibleRect;
visibleRect.origin.x = _scrollView.contentOffset.x * scale;
visibleRect.origin.y = _scrollView.contentOffset.y * scale;
visibleRect.size.width = _scrollView.bounds.size.width * scale;
visibleRect.size.height = _scrollView.bounds.size.height * scale;
NSLog(#"Oh and here's that CGRect: %f", visibleRect.origin.x);
NSLog(#"Oh and here's that CGRect: %f", visibleRect.origin.y);
NSLog(#"Oh and here's that CGRect: %f", visibleRect.size.width);
NSLog(#"Oh and here's that CGRect: %f", visibleRect.size.height);
CGImageRef imageRef = CGImageCreateWithImageInRect([image CGImage], visibleRect);
UIImage *croppedImage = [[UIImage alloc] initWithCGImage:imageRef];
CGImageRelease(imageRef);
return croppedImage;
}
I need the image to be cropped to a CGSize of (321,115). Upon cropping the image and seeing the print results, I can see that visibleRect is (0,0,321,115) - what it is supposed to be, the croppedImage UIImage then has width:321 and height:115. for some reason however the image appears to be zoomed in entirely too far (the method cropped a smaller portion of the original image to a size of 321x115).
Why is this method not correctly cropping my image?
-As a side note: When I call this method, I am calling like so _croppedImage = [self cropImage:_imageView.image]; which sets a UIImage property of a custom UIView class to the cropped image.
Please try this function. It may help you.
Parameters:
UIImage
CGSize (321,115) or any size
// crop image - image will crop from full image
- (UIImage *)cropImageWithImage:(UIImage *)image scaledToSize:(CGSize)newSize {
double ratio;
double delta;
CGPoint offset;
//make a new square size, that is the resized imaged width
CGSize sz = CGSizeMake(newSize.width, newSize.width);
//figure out if the picture is landscape or portrait, then
//calculate scale factor and offset
if (image.size.width > image.size.height) {
ratio = newSize.width / image.size.width;
delta = (ratio*image.size.width - ratio*image.size.height);
offset = CGPointMake(delta/2, 0);
}
else {
ratio = newSize.width / image.size.height;
delta = (ratio*image.size.height - ratio*image.size.width);
offset = CGPointMake(0, delta/2);
}
//make the final clipping rect based on the calculated values
CGRect clipRect = CGRectMake(-offset.x,
-offset.y,
(ratio * image.size.width) + delta,
(ratio * image.size.height) + delta);
//start a new context, with scale factor 0.0 so retina displays get
//high quality image
if ([[UIScreen mainScreen] respondsToSelector:#selector(scale)]) {
UIGraphicsBeginImageContextWithOptions(sz, YES, 0.0);
} else {
UIGraphicsBeginImageContext(sz);
}
UIRectClip(clipRect);
[image drawInRect:clipRect];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
To crop only selected portion of image
Please check this link
This question already has answers here:
Resize UIImage by keeping Aspect ratio and width
(19 answers)
Closed 7 years ago.
I'm using the UIImagePickerController to chose an image from my library and uploading it to Parse. How can I resize my image's height only? I want the image to keep it's aspect ratio but I don't want the height to be taller than 1000px.
Right now I'm resizing both the width and height to a fixed number with this code:
ViewController.h
- (UIImage *)resizeImage:(UIImage *)image toWidth:(float)width andHeight:(float)height;
ViewController.h
- (UIImage *)resizeImage:(UIImage *)image toWidth:(float)width andHeight:(float)height {
CGSize newSize = CGSizeMake(width, height);
CGRect newRectangle = CGRectMake(0, 0, width, height);
UIGraphicsBeginImageContext(newSize);
[self.image drawInRect:newRectangle];
UIImage *resizedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return resizedImage;
}
- (IBAction)createProduct:(id)sender {
UIImage *newImage = [self resizeImage:self.image toWidth:750.0f andHeight:1000.0f];
NSData *imageData = UIImagePNGRepresentation(newImage);
PFFile *imageFile = [PFFile fileWithName:#"image.jpg" data:imageData];
}
Thanks.
+(UIImage*)imageWithImage: (UIImage*) sourceImage scaledToHeight: (float) i_height
{
float oldHeight = sourceImage.size.height;
float scaleFactor = i_height / oldHeight;
float newWidth = sourceImage.size.width* scaleFactor;
float newHeight = oldHeight * scaleFactor;
UIGraphicsBeginImageContext(CGSizeMake(newWidth, newHeight));
[sourceImage drawInRect:CGRectMake(0, 0, newWidth, newHeight)];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
You will have to get the aspect ration of the original dimensions and multiply that with your new height
Pseudocode
if (height > 1000){
aspectRatio = width/height;
height = 1000;
width = height * aspectRatio
}
- (IBAction)createProduct:(id)sender {
UIImage *newImage;
if (self.image.size.height > 1000){
CGFloat aspectRatio = self.image.size.width/self.image.size.height;
CGFloat height = 1000;
CGFloat width = height * aspectRatio;
newImage = [self resizeImage:self.image toWidth:width andHeight:height];
} else {
newImage = self.image;
}
NSData *imageData = UIImagePNGRepresentation(newImage);
PFFile *imageFile = [PFFile fileWithName:#"image.jpg" data:imageData];
}
I have been looking around to find a way to crop an image (imageView) inside ScrollView. What i need to achieve here is user pinch to zoom an image, (which is working great) and then able to crop ONLY the part of the image that is shown on the screen after the zoom. so in another words, if i have a series of number 1 to 10, user zoom it to see only number 4 and 5 and when user taps crop, i ONLY need image of 4 and 5 that was visible at the time of crop. I'm using this code...
- (UIImage *)croppedImageWithImage:(UIImage *)image zoom:(CGFloat)zoom
{
CGFloat zoomReciprocal = 1.0f / zoom;
CGRect croppedRect = CGRectMake(self.scrollView.contentOffset.x*zoom,
self.scrollView.contentOffset.y*zoom,
image.size.width * zoomReciprocal,
image.size.height * zoomReciprocal);
CGImageRef croppedImageRef = CGImageCreateWithImageInRect([image CGImage], croppedRect);
UIImage* croppedImage = [[UIImage alloc] initWithCGImage:croppedImageRef scale:[image scale] orientation:[image imageOrientation]];
CGImageRelease(croppedImageRef);
return croppedImage;
}
This method crops the image however, the x and y values are incorrect... What do i have to do to get the correct x and y of my crop area?
FYI.. the image i'm trying to crop is 2200 * 3200, not sure if that would make any difference?
I solved it!! here is the updated method for others who might come across this issue.
- (UIImage *)croppedImageWithImage:(UIImage *)image zoom:(CGFloat)zoom {
CGFloat zoomReciprocal = 1.0f / zoom;
CGFloat xOffset = image.size.width / self.scrollViewBackground.contentSize.width;
CGFloat yOffset = image.size.height / self.scrollViewBackground.contentSize.height;
CGRect croppedRect = CGRectMake(self.scrollViewBackground.contentOffset.x * xOffset,
self.scrollViewBackground.contentOffset.y * yOffset,
image.size.width * zoomReciprocal,
image.size.height * zoomReciprocal);
CGImageRef croppedImageRef = CGImageCreateWithImageInRect([image CGImage], croppedRect);
UIImage *croppedImage = [[UIImage alloc] initWithCGImage:croppedImageRef scale:[image scale] orientation:[image imageOrientation]];
CGImageRelease(croppedImageRef);
return croppedImage;
}
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.
In my app, I am taking picture with camera and displaying it in 320*320 UIView. But as the image resolution is more than that of UIView its kinda look squeezed. Is there any way I can resize that image?
Here's how you can resize the image while preserving its aspect ratio. The code below is from a category for UIImage:
+ (UIImage*)imageWithImage:(UIImage *)image
scaledToSize:(CGSize)newSize
{
float heightToWidthRatio = image.size.height / image.size.width;
float scaleFactor = 1;
if(heightToWidthRatio > 0) {
scaleFactor = newSize.height / image.size.height;
} else {
scaleFactor = newSize.width / image.size.width;
}
CGSize newSize2 = newSize;
newSize2.width = image.size.width * scaleFactor;
newSize2.height = image.size.height * scaleFactor;
UIGraphicsBeginImageContext(newSize2);
[image drawInRect:CGRectMake(0,0,newSize2.width,newSize2.height)];
UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
I do this, but first I enable the photo picker to editable so it is default 1:1 aspect, like so:
imgPicker.allowsImageEditing = YES; //I think this is what you're really looking for
then I resize the image using this method:
-(UIImage*)resizeImage:(UIImage*)image{
CGSize newSize = CGSizeMake(480.0, 480.0);
UIGraphicsBeginImageContext(newSize);
[image drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
UIImage* newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}