I want to crop an image which is on the UIImageview into any shape
You set the clipping path and voila:
// Load image thumbnail
NSString *imageName = [self.picArray objectAtIndex:indexPath.row];
UIImage *image = [UIImage imageNamed:imageName];
CGSize imageSize = image.size;
CGRect imageRect = CGRectMake(0, 0, imageSize.width, imageSize.height);
UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0.0);
// Create the clipping path and add it
UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:imageRect cornerRadius:5.0f];
[path addClip];
[image drawInRect:imageRect];
UIImage *roundedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
This code loads an image and creates a path by rounding the rectangle, the result is that the final image has been clipped, i.e. rounded corners. RoundedImage is the result.
You can use a CGImageMask.
A sample exists in the class QuartzMaskingView of Apple's QuartzDemo.
Related
In objective-c, I make a circle shape programmatically by following codes:
+(UIImage *)makeRoundedImage:(CGSize) size backgroundColor:(UIColor *) backgroundColor cornerRadius:(int) cornerRadius
{
UIImage* bgImage = [self imageWithColor:backgroundColor andSize:size];;
CALayer *imageLayer = [CALayer layer];
imageLayer.frame = CGRectMake(0, 0, size.width, size.height);
imageLayer.contents = (id) bgImage.CGImage;
imageLayer.masksToBounds = YES;
imageLayer.cornerRadius = cornerRadius;
UIGraphicsBeginImageContext(bgImage.size);
[imageLayer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *roundedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return roundedImage;
}
The imageWithColor method is as following:
+(UIImage *)imageWithColor:(UIColor *)color andSize:(CGSize)size
{
//quick fix, or pop up CG invalid context 0x0 bug
if(size.width == 0) size.width = 1;
if(size.height == 0) size.height = 1;
//---quick fix
UIImage *img = nil;
CGRect rect = CGRectMake(0, 0, size.width, size.height);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context,
color.CGColor);
CGContextFillRect(context, rect);
img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return img;
}
Then I used it to create a pure color circle shape image, but what I found is the circle image is not perfect rounded. As an example, please see following code:
CGSize size = CGSizeMake(diameter, diameter);
int r = ceil((float)diameter/2.0);
UIImage *imageNormal = [self makeRoundedImage:size backgroundColor:backgroundColor cornerRadius:r];
[slider setThumbImage:imageNormal forState:UIControlStateNormal];
First I created a circle image, then I set the image as the thumb to a UISlider. But what shown is as the picture shown below:
You can see the circle is not an exact circle. I'm thinking probably it caused by the screen resolution issue? Because if I use an image resource for the thumb, I need add #2x. Anybody know the reason? Thanx in advance.
updated on 8th Aug 2015.
Further to this question and the answer from #Noah Witherspoon, I found the blurry edge issue has been solved. But still, the circle looks like being cut. I used the code as following:
CGRect rect = CGRectMake(0.0f, 0.0f, radius*2.0f, radius*2.0f);
UIGraphicsBeginImageContextWithOptions(rect.size, NO, 0.0);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, color.CGColor);
CGContextFillEllipseInRect(context, rect);
UIImage* image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
And the circle looks like:
You can see the edge has been cut.
I changed the code as following:
CGRect rect = CGRectMake(0.0f, 0.0f, radius*2.0f+4, radius*2.0f+4);
CGRect rectmin = CGRectMake(2.0f, 2.0f, radius*2, radius*2);
UIGraphicsBeginImageContextWithOptions(rect.size, NO, 0.0);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, color.CGColor);
CGContextFillEllipseInRect(context, rectmin);
UIImage* image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
You can see the circle looks better(The top edge and the bottom edge):
I made the fill rect size smaller, and the edge looks better, but I don't think it's a nice solution. Still, does anybody know why this happen?
From your screenshot it looks like you do actually have a circular image, but its scale is wrong—it’s not Retina—so it looks blurry and not-circular. The key thing is that instead of using UIGraphicsBeginImageContext which defaults to a scale of 1.0 (as compared to your screen, which is at a scale of 2.0 or 3.0), you should be using UIGraphicsBeginImageContextWithOptions. Also, you don’t need to make a layer or a view to draw a circle in an image context.
+ (UIImage *)makeCircleImageWithDiameter:(CGFloat)diameter color:(UIColor *)color {
UIGraphicsBeginImageContextWithOptions(CGSizeMake(diameter, diameter), NO, 0 /* scale (0 means “use the current screen’s scale”) */);
[color setFill];
CGContextFillEllipseInRect(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, diameter, diameter));
UIImage *image = UIGraphicsGetImageFromCurrentContext();
UIGraphicsEndImageContext();
return image;
}
If you want to get a circle every time try this:
- (UIImage *)makeCircularImage:(CGSize)size backgroundColor:(UIColor *)backgroundColor {
CGSize squareSize = CGSizeMake((size.width > size.height) ? size.width : size.height,
(size.width > size.height) ? size.width : size.height);
UIView *circleView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, squareSize.width, squareSize.height)];
circleView.layer.cornerRadius = circleView.frame.size.height * 0.5f;
circleView.backgroundColor = backgroundColor;
circleView.opaque = NO;
UIGraphicsBeginImageContextWithOptions(circleView.bounds.size, circleView.opaque, 0.0);
[circleView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage * img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return img;
}
Hi i want to covert my UIView to UIImage in particular frame size kindly help me.
I have 'UITableView` which is added as subview of 'UIScrollView' for horizontal scroll, my table view frame size is (0, 0, 12000, 768).
I want to convert the current visible are of my UITableView as UIImage after scrolling.
Example:
if i scrolled my table view horizontally some distance means that current visible are is (150,0,1200,768) that means full device screen.
if i use the following code:
UIGraphicsBeginImageContext(self.frame.size);
[self.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *backgroundImage = UIGraphicsGetImageFromCurrentImageContext();
its capturing always the frame size of (0, 0, 1200, 768) only.
so, how can i set the origin of image capturing.
Kindly help me out.... Thanks in advance....
- (UIImage *)rasterizedImageInView:(UIView *)view atRect:(CGRect)rect {
UIGraphicsBeginImageContextWithOptions(rect.size, view.opaque, 0.0);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(context, -rect.origin.x, -rect.origin.y);
[view.layer renderInContext:context];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
This will allow you to capture a UIImage from a particular region within a UIView as defined by a CGRect.
CGRect rect = [self.view bounds];
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
[self.view.layer renderInContext:context];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
Try this.
UIView *viewprint=[[UIView alloc] initWithFrame:CGRectMake(0, 0, width, height)];
viewprint.backgroundColor=[UIColor whiteColor];
tableView.frame = CGRectMake(0, 0, width, height);
[viewprint addSubview:tableView];
UIGraphicsBeginImageContext(viewprint.size);
CGContextRef context = UIGraphicsGetCurrentContext();
[view.layer renderInContext:context];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
After trying the answer posted here the image that gets returned is of a very poor quality on the retina display. My mask image has a white background and black contents.
Output: https://dzwonsemrish7.cloudfront.net/items/22373o2Z260d3S051a05/Screenshot%202013.01.02%2000.04.57.png?v=34c4ab14
Code:
CGRect rect = CGRectMake(0.0f, 0.0f, 61.0f, 53.0f);
UIGraphicsBeginImageContextWithOptions(rect.size, NO, 2);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [UIColor blueColor].CGColor);
CGContextFillRect(context, rect);
UIImage *imageGradient = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImage *toggleImage = [UIImage imageNamed:#"RotationToggle.png"];
UIImage *inputImage = imageGradient;
CGImageRef maskRef = toggleImage.CGImage;
CGImageRef mask = CGImageMaskCreate(CGImageGetWidth(maskRef),
CGImageGetHeight(maskRef),
CGImageGetBitsPerComponent(maskRef),
CGImageGetBitsPerPixel(maskRef),
CGImageGetBytesPerRow(maskRef),
CGImageGetDataProvider(maskRef), NULL, false);
CGImageRef masked = CGImageCreateWithMask(imageGradient.CGImage, mask);
CGImageRelease(mask);
UIImage *maskedImage = [UIImage imageWithCGImage:masked scale:inputImage.scale orientation:0];
CGImageRelease(masked);
I am not completely sure, but try changing this line:
UIImage *toggleImage = [UIImage imageNamed:#"RotationToggle.png"];
to this:
UIImage *toggleImage = [UIImage imageNamed:#"RotationToggle"];
or naive this:
UIImage *toggleImage = [UIImage imageNamed:#"RotationToggle#2x.png"];
The thing is: I think you force it to use low-quality image by assigning it this way. When skipping extension, Xcode will automatically look for Retina image and assign it if there exists one.
I may be wrong though, sorry if so.
I have a square image 40x40 that I want to make round via clipping, but also put a black 5 pixel border around the image.
I have the following which is masking the square image so its now round
UIImage *image = self.imageView.image;
CGSize imageSize = image.size;
CGRect imageRect = CGRectMake(0, 0, imageSize.width, imageSize.height);
UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0.0);
// Create the clipping path and add it
UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:imageRect];
[path addClip];
[image drawInRect:imageRect];
UIImage *roundedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
self.imageView.image = roundedImage;
But now I need to also add a round border around it. Do I need a new path or can I just tack onto the one one in the code above?
Add the following three lines in your code (with whatever color and stroke width you want):
CGContextSetStrokeColorWithColor(ctx, [[UIColor greenColor] CGColor]);
[path setLineWidth:50.0f];
[path stroke];
So it becomes:
UIGraphicsBeginImageContextWithOptions(imageSize, NO, 0.0);
CGContextRef ctx = UIGraphicsGetCurrentContext();
// Create the clipping path and add it
UIBezierPath *path = [UIBezierPath bezierPathWithOvalInRect:imageRect];
[path addClip];
[image drawInRect:imageRect];
CGContextSetStrokeColorWithColor(ctx, [[UIColor greenColor] CGColor]);
[path setLineWidth:50.0f];
[path stroke];
UIImage *roundedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
self.imageView.image = roundedImage;
I'm facing the following problem : I have to merge two images A and B to create a new image C as a result of the merging.
I already know how to merge two images but in this case my goal is a little bit different.
I would like that image A will be the background for Image B.
For instance if image A size is 500x500 and image B size is 460x460 I would like that image C (the image result of the merging) will be 500x500, with image B (460x460) centered in it.
Thanks in advance for any help or suggestion
This is what I've done in my app, but without using UIImageView:
UIImage *bottomImage = [UIImage imageNamed:#"bottom.png"]; //background image
UIImage *image = [UIImage imageNamed:#"top.png"]; //foreground image
CGSize newSize = CGSizeMake(width, height);
UIGraphicsBeginImageContext( newSize );
// Use existing opacity as is
[bottomImage drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
// Apply supplied opacity if applicable
[image drawInRect:CGRectMake(0,0,newSize.width,newSize.height) blendMode:kCGBlendModeNormal alpha:0.8];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
If the image already has opacity, you do not need to set it (as in bottomImage) otherwise you can set it (as with image).
After this UIImage is created then you can embed it in your UIImageView
UPDATE: Thanks to Ahmet AkkoK - for Swift (2.2) users blend mode macro has changed. CGBlendMode .kCGBlendModeNormal is replaced with CGBlendMode.Normal
Hey i got multiple images add same background with different foreground
This is my code
UIImage *bottomImage = [UIImage imageNamed:#"photo 2.JPG"]; //background image
UIImage *image = [UIImage imageNamed:#"photo 3.JPG"]; //foreground image
UIImage *image1 = [UIImage imageNamed:#"photo 4.JPG"]; //foreground image
UIImage *image2 = [UIImage imageNamed:#"photo 5.JPG"]; //foreground image
CGSize newSize = CGSizeMake(320, 480);
UIGraphicsBeginImageContext( newSize );
// Use existing opacity as is
[bottomImage drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
// Apply supplied opacity if applicable
[image drawInRect:CGRectMake(0,0,newSize.width,newSize.height) blendMode:kCGBlendModeNormal alpha:0.4];
[image1 drawInRect:CGRectMake(0,0,newSize.width,newSize.height) blendMode:kCGBlendModeNormal alpha:0.3];
[image2 drawInRect:CGRectMake(0,0,newSize.width,newSize.height) blendMode:kCGBlendModeNormal alpha:0.2];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
resultView = [[UIImageView alloc] initWithImage:newImage];
resultView.frame = CGRectMake(0, 0,320,460);
[self.view addSubview:resultView];
Swift version
Copy/Paste to Playground
var bottomImage:UIImage = UIImage(named:"avatar_4.png") //background image
var imageTop:UIImage = UIImage(named:"group_4.png") //top image
var newSize = CGSizeMake(bottomImage.size.width, bottomImage.size.height)
UIGraphicsBeginImageContext( newSize )
bottomImage.drawInRect(CGRectMake(0,0,newSize.width,newSize.height))
// decrease top image to 36x36
imageTop.drawInRect(CGRectMake(18,18,36,36), blendMode:kCGBlendModeNormal, alpha:1.0)
var newImage:UIImage = UIGraphicsGetImageFromCurrentImageContext()
var imageData = UIImagePNGRepresentation(newImage)
To load images from playground:
Open playground file and create there folder Resources
copy images to this folder
Just made quick paste function for those of you who wanted to use Srikar Appal answer. (if in case background & foreground images are of different sizes)
- (UIImage *) mergeImages:(NSString *)bgImageFileName foreGround:(NSString *)fgImageFileName {
UIImage *bottomImage = [UIImage imageNamed:bgImageFileName]; //background image
UIImage *image = [UIImage imageNamed:fgImageFileName]; //foreground image
CGSize newSize = CGSizeMake(bottomImage.size.width, bottomImage.size.height);
UIGraphicsBeginImageContext(newSize);
// Use existing opacity as is
[bottomImage drawInRect:CGRectMake(0,0,newSize.width,newSize.height)];
// Apply supplied opacity if applicable
// Change xPos, yPos if applicable
[image drawInRect:CGRectMake(11,11,image.size.width,image.size.height) blendMode:kCGBlendModeNormal alpha:1.0];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
in Swift:
let bottomImage = UIImage(named: "Bottom_Image.png")
let frontImage = UIImage (named: "Front_Image.png")
let size = CGSize(width: 67, height: 55)
UIGraphicsBeginImageContext(size)
let areaSize = CGRect(x: 0, y: 0, width: size.width, height: size.height)
let frontImageSize = CGRect(x: 14, y: 3, width: 40, height: 40)
bottomImage!.drawInRect(areaSize, blendMode: CGBlendMode.Normal, alpha: 1.0)
frontImage!.drawInRect(frontImageSize, blendMode: CGBlendMode.Normal, alpha: 1.0)
let newImage:UIImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
Thanks #Srikar Appal for iOS soultion.
For anyone who is looking for merge in OS X:
- (NSImage *) mergeImages:(NSString *)bgImageFileName foreGround:(NSString *)fgImageFileName {
NSImage *bottomImage = [NSImage imageNamed:bgImageFileName];
NSImage *overlayedImage = [NSImage imageNamed:fgImageFileName];
NSSize newSize = NSMakeSize(bottomImage.size.width, bottomImage.size.height);
NSSize overlaySize = NSMakeSize(newSize.width/2, newSize.height/2); //change the size according to your requirements
NSImage *newImage = [[NSImage alloc] initWithSize:newSize];
[newImage lockFocus];
[bottomImage drawInRect:NSMakeRect(0, 0, newSize.width, newSize.height)];
[overlayedImage drawInRect:NSMakeRect(newSize.width-overlaySize.width, 0, overlaySize.width, overlaySize.height)]; //set the position as required
[newImage unlockFocus];
return newImage;
}
You can go with another trick as described below:
Add first image to a imageView.
Add second image to another imageView.
Add both the above imageViews in a single main imageView and access the combined image by property of imageView : mainImageView.image
Have a look at the code below :
CGRect rect= investmentDetailTblView.frame;
int rows = investmentDetailArray.count;
CGFloat heightFinal = 5;
CGRect frame1;
for (int i=0; i<rows; i++)
{
frame1 = [investmentDetailTblView rectForRowAtIndexPath:[NSIndexPath indexPathForRow:i inSection:0]];
CGFloat height = frame1.size.height;
heightFinal = heightFinal + height;
}
rect.size.height = heightFinal;
investmentDetailTblView.frame=rect;
UIImageView *imageViewTable = [[UIImageView alloc] init];
[imageViewTable setFrame:CGRectMake(0, 0, frame1.size.width, heightFinal)];
[investmentDetailTblView reloadData];
if ([[UIScreen mainScreen] respondsToSelector:#selector(scale)])
UIGraphicsBeginImageContextWithOptions(investmentDetailTblView.bounds.size, NO, [UIScreen mainScreen].scale);
else
UIGraphicsBeginImageContext(investmentDetailTblView.bounds.size);
[investmentDetailTblView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
imageViewTable.image = image; //Adding the table image to the image view.
CGRect frame=CGRectMake(0, heightFinal+5, investmentDetailTblView.frame.size.width, 20) ;
UIView *footerView=[DataStore kkrLogoView];
footerView.frame=frame;
if ([[UIScreen mainScreen] respondsToSelector:#selector(scale)])
UIGraphicsBeginImageContextWithOptions(footerView.frame.size, NO, [UIScreen mainScreen].scale);
else
UIGraphicsBeginImageContext(footerView.frame.size);
[footerView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *kkrLogoImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageView *imageViewFooter = [[UIImageView alloc] init];
[imageViewFooter setFrame:CGRectMake(0, heightFinal, footerView.frame.size.width, footerView.frame.size.height)];
imageViewFooter.image = kkrLogoImage; //Adding the footer image to the image view.
UIImageView *mainImageView = [[UIImageView alloc] init];
[mainImageView setFrame:CGRectMake(0, 0, frame1.size.width, (heightFinal+footerView.frame.size.height))];
[mainImageView addSubview:imageViewTable];
[mainImageView addSubview:imageViewFooter];
if ([[UIScreen mainScreen] respondsToSelector:#selector(scale)])
UIGraphicsBeginImageContextWithOptions(mainImageView.frame.size, NO, [UIScreen mainScreen].scale);
else
UIGraphicsBeginImageContext(mainImageView.frame.size);
[mainImageView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *finalImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();