Crop image in oval shape - iphone

I am working on App in which i need to give an cropping option. Once i select the image from camera or gallery it should open on editing page where we have Oval image with zooming & moving option. Once we click on apply the captured image should cropped in oval shape.
Now following screen is from aviary sdk. But it has square cropping & in need the cropping in oval shape. I tried to customise it but not able to do so.
Can anyone suggest me the easiest or the best suitable way to implement this.
Thanks.

- (UIImage *)croppedPhoto {
// For dealing with Retina displays as well as non-Retina, we need to check
// the scale factor, if it is available. Note that we use the size of teh cropping Rect
// passed in, and not the size of the view we are taking a screenshot of.
CGRect croppingRect = CGRectMake(imgMaskImage.frame.origin.x,
imgMaskImage.frame.origin.y, imgMaskImage.frame.size.width,
imgMaskImage.frame.size.height);
imgMaskImage.hidden=YES;
if ([[UIScreen mainScreen] respondsToSelector:#selector(scale)]) {
UIGraphicsBeginImageContextWithOptions(croppingRect.size, YES, [UIScreen mainScreen].scale);
} else {
UIGraphicsBeginImageContext(croppingRect.size);
}
// Create a graphics context and translate it the view we want to crop so
// that even in grabbing (0,0), that origin point now represents the actual
// cropping origin desired:
CGContextRef ctx = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(ctx, -croppingRect.origin.x, -croppingRect.origin.y);
[self.view.layer renderInContext:ctx];
// Retrieve a UIImage from the current image context:
UIImage *snapshotImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
// Return the image in a UIImageView:
return snapshotImage;
}

This type of masking you can perform or else you use the coco controls
.h file:-
#interface yourClass : UIImageView
#end
.m file:-
#import <QuartzCore/QuartzCore.h>
#implementation yourClass
- (void)awakeFromNib
{
[super awakeFromNib];
CALayer *mask = [CALayer layer];
mask.contents = (id)[[UIImage imageNamed:#"ovalMask.png"] CGImage];
CGSize size = self.frame.size;
mask.frame = CGRectMake(0, 0, size.width, size.height);
self.layer.mask = mask;
[self.layer setMasksToBounds:YES];
}
#end

Related

iPhone programmatically crop a square image to appear as circle

I'm trying to create an image for a custom style UIButton using an image from the camera roll on iPhone. The button has a circular background and effectively appears as a circle. Now I need an image to go in the middle of the button that also appears round.
How do I cut a square UIImage to appear round with transparency outside of the round area?
If masking is involved, do I need to pre-render a mask or can I create one programmatically(ex: a circle)?
Thank you!
I have never done anything like that, but try using QuartzCore framework and its' cornerRadius property. Example:
#import <QuartzCore/QuartzCore.h>
//some other code ...
UIImageView *imgView = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, 100, 100)];
imgView.layer.cornerRadius = 10.0f;
play around with it a bit and you will get what you want.
Hope it helps
Yes you can use CoreGraphics to draw the mask dynamically.
Then you can create the masked image.
Example for masking:
- (UIImage*) maskImage:(UIImage *)image withMask:(UIImage *)maskImage
{
CGImageRef maskRef = maskImage.CGImage;
CGImageRef mask = CGImageMaskCreate(CGImageGetWidth(maskRef),
CGImageGetHeight(maskRef),
CGImageGetBitsPerComponent(maskRef),
CGImageGetBitsPerPixel(maskRef),
CGImageGetBytesPerRow(maskRef),
CGImageGetDataProvider(maskRef), NULL, false);
CGImageRef maskedImageRef = CGImageCreateWithMask([image CGImage], mask);
UIImage *maskedImage = [UIImage imageWithCGImage:maskedImageRef];
CGImageRelease(maskedImageRef);
CGImageRelease(mask);
return maskedImage;
}
I started looking into this a couple of weeks back. I tried all the suggestions here, none of which worked well. In the great tradition of RTFM I went and read Apple's documentation on Quartz 2D Programming and came up with this. Please try it out and let me know how you go.
The code could be fairly easily altered to crop to an elipse, or any other shape defined by a path.
Make sure you include Quartz 2D in your project.
#include <math.h>
+ (UIImage*)circularScaleNCrop:(UIImage*)image: (CGRect) rect{
// This function returns a newImage, based on image, that has been:
// - scaled to fit in (CGRect) rect
// - and cropped within a circle of radius: rectWidth/2
//Create the bitmap graphics context
UIGraphicsBeginImageContextWithOptions(CGSizeMake(rect.size.width, rect.size.height), NO, 0.0);
CGContextRef context = UIGraphicsGetCurrentContext();
//Get the width and heights
CGFloat imageWidth = image.size.width;
CGFloat imageHeight = image.size.height;
CGFloat rectWidth = rect.size.width;
CGFloat rectHeight = rect.size.height;
//Calculate the scale factor
CGFloat scaleFactorX = rectWidth/imageWidth;
CGFloat scaleFactorY = rectHeight/imageHeight;
//Calculate the centre of the circle
CGFloat imageCentreX = rectWidth/2;
CGFloat imageCentreY = rectHeight/2;
// Create and CLIP to a CIRCULAR Path
// (This could be replaced with any closed path if you want a different shaped clip)
CGFloat radius = rectWidth/2;
CGContextBeginPath (context);
CGContextAddArc (context, imageCentreX, imageCentreY, radius, 0, 2*M_PI, 0);
CGContextClosePath (context);
CGContextClip (context);
//Set the SCALE factor for the graphics context
//All future draw calls will be scaled by this factor
CGContextScaleCTM (context, scaleFactorX, scaleFactorY);
// Draw the IMAGE
CGRect myRect = CGRectMake(0, 0, imageWidth, imageHeight);
[image drawInRect:myRect];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
Include the following code in your UIView class replacing "monk2.png" with your own image name.
- (void)drawRect:(CGRect)rect
{
UIImage *originalImage = [UIImage imageNamed:[NSString stringWithFormat:#"monk2.png"]];
CGFloat oImageWidth = originalImage.size.width;
CGFloat oImageHeight = originalImage.size.height;
// Draw the original image at the origin
CGRect oRect = CGRectMake(0, 0, oImageWidth, oImageHeight);
[originalImage drawInRect:oRect];
// Set the newRect to half the size of the original image
CGRect newRect = CGRectMake(0, 0, oImageWidth/2, oImageHeight/2);
UIImage *newImage = [self circularScaleNCrop:originalImage :newRect];
CGFloat nImageWidth = newImage.size.width;
CGFloat nImageHeight = newImage.size.height;
//Draw the scaled and cropped image
CGRect thisRect = CGRectMake(oImageWidth+10, 0, nImageWidth, nImageHeight);
[newImage drawInRect:thisRect];
}
Here is a quick way to create rounded corners on a square ImageView to make it look like a perfect circle. Basically you apply a corner radius equal to 1/2 the width (width == height on a square image).
#import <QuartzCore/QuartzCore.h> //you need QuartzCore
...
float width = imageView.bounds.size.width; // we can also use the frame property instead of bounds since we just care about the Size and don't care about position
imageView.layer.cornerRadius = width/2;
{
imageView.layer.cornerRadius = imageView.frame.size.height /2;
imageView.layer.masksToBounds = YES;
imageView.layer.borderWidth = 0;
}
UIImage category to mask an image with a circle:
UIImage *originalImage = [UIImage imageNamed:#"myimage.png"];
UImage *myRoundedImage = [UIImage roundedImageWithImage:originalImage];
Get it here.
I have another solution:
- (UIImage *)roundedImageWithRect:(CGRect)rect radius:(CGFloat)radius
{
UIGraphicsBeginImageContextWithOptions(rect.size, NO, 0);
UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:CGRectMake(0, 0, rect.size.width, rect.size.height) cornerRadius:radius];
CGFloat imageRatio = self.size.width / self.size.height;
CGSize imageSize = CGSizeMake(rect.size.height * imageRatio, rect.size.height);
CGRect imageRect = CGRectMake(0, 0, imageSize.width, imageSize.height);
[path addClip];
[self drawInRect:imageRect];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
This variant is better for performance than set cornerRadius directly.
Personally, I'd create a transparent circle image with opaque corners to overlay the photo. This solution is only suitable where you will be placing the image in one place on the UI, and assumes the opaque corners will blend in with the background.
Following is the answer I given in How to crop UIImage on oval shape or circle shape? to make the image circle. It works for me..
Download the Support archive file
#import "UIImage+RoundedCorner.h"
#import "UIImage+Resize.h"
Following lines used to resize the image and convert in to round with radius
UIImage *mask = [UIImage imageNamed:#"mask.jpg"];
mask = [mask resizedImage:CGSizeMake(47, 47) interpolationQuality:kCGInterpolationHigh ];
mask = [mask roundedCornerImage:23.5 borderSize:1];
Just use
_profilePictureImgView.layer.cornerRadius = 32.0f;
_profilePictureImgView.layer.masksToBounds = YES;

iOS - How to achieve emboss effect for the text on UILabel?

Can I know how to have the emboss effect as the text "Reminders" as shown on the picture?
It looks like the text are embedded?
Thanks
UPDATE FOR iOS 7.0
In iOS 7.0, Apple added a new attribute, NSTextEffectAttributeName, for attributed strings. If your deployment target is iOS 7.0 or later, you can set this attribute to NSTextEffectLetterpressStyle to draw an attributed string in an embossed style.
ORIGINAL
I can't say for certain how Apple draws the embossed text. It looks to me like they fill the string glyphs with a reddish color, then apply a shadow around the interior edges of the glyphs, and also apply a very faint shadow along the top outside edges of the glyphs. I tried it out and here's what it looks like:
On top is my rendering. Below that is a simple UILabel with shadow as Chris suggested in his answer. I put a screen shot of the Reminders app in the background.
Here's my code.
First, you need a function that creates an image mask of your string. You'll use the mask to draw the string itself, and then to draw a shadow that only appears around the inside edges of the string. This image just has an alpha channel and no RGB channels.
- (UIImage *)maskWithString:(NSString *)string font:(UIFont *)font size:(CGSize)size
{
CGRect rect = { CGPointZero, size };
CGFloat scale = [UIScreen mainScreen].scale;
CGColorSpaceRef grayscale = CGColorSpaceCreateDeviceGray();
CGContextRef gc = CGBitmapContextCreate(NULL, size.width * scale, size.height * scale, 8, size.width * scale, grayscale, kCGImageAlphaOnly);
CGContextScaleCTM(gc, scale, scale);
CGColorSpaceRelease(grayscale);
UIGraphicsPushContext(gc); {
[[UIColor whiteColor] setFill];
[string drawInRect:rect withFont:font];
} UIGraphicsPopContext();
CGImageRef cgImage = CGBitmapContextCreateImage(gc);
CGContextRelease(gc);
UIImage *image = [UIImage imageWithCGImage:cgImage scale:scale orientation:UIImageOrientationDownMirrored];
CGImageRelease(cgImage);
return image;
}
Second, you need a function that inverts that mask. You'll use this to make CoreGraphics draw a shadow around the inside edges of the string. This needs to be a full RGBA image. (iOS doesn't seem to support grayscale+alpha images.)
- (UIImage *)invertedMaskWithMask:(UIImage *)mask
{
CGRect rect = { CGPointZero, mask.size };
UIGraphicsBeginImageContextWithOptions(rect.size, NO, mask.scale); {
[[UIColor blackColor] setFill];
UIRectFill(rect);
CGContextClipToMask(UIGraphicsGetCurrentContext(), rect, mask.CGImage);
CGContextClearRect(UIGraphicsGetCurrentContext(), rect);
}
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
You can use those in a function that draws the string in red and applies a shadow to its interior edges.
-(UIImage *)imageWithInteriorShadowAndString:(NSString *)string font:(UIFont *)font textColor:(UIColor *)textColor size:(CGSize)size
{
CGRect rect = { CGPointZero, size };
UIImage *mask = [self maskWithString:string font:font size:rect.size];
UIImage *invertedMask = [self invertedMaskWithMask:mask];
UIImage *image;
UIGraphicsBeginImageContextWithOptions(rect.size, NO, [UIScreen mainScreen].scale); {
CGContextRef gc = UIGraphicsGetCurrentContext();
// Clip to the mask that only allows drawing inside the string's image.
CGContextClipToMask(gc, rect, mask.CGImage);
// We apply the mask twice because we're going to draw through it twice.
// Only applying it once would make the edges too sharp.
CGContextClipToMask(gc, rect, mask.CGImage);
mask = nil; // done with mask; let ARC free it
// Draw the red text.
[textColor setFill];
CGContextFillRect(gc, rect);
// Draw the interior shadow.
CGContextSetShadowWithColor(gc, CGSizeZero, 1.6, [UIColor colorWithWhite:.3 alpha:1].CGColor);
[invertedMask drawAtPoint:CGPointZero];
invertedMask = nil; // done with invertedMask; let ARC free it
image = UIGraphicsGetImageFromCurrentImageContext();
}
UIGraphicsEndImageContext();
return image;
}
Next you need a function that takes an image and returns a copy with a faint upward shadow.
- (UIImage *)imageWithUpwardShadowAndImage:(UIImage *)image
{
UIGraphicsBeginImageContextWithOptions(image.size, NO, image.scale); {
CGContextSetShadowWithColor(UIGraphicsGetCurrentContext(), CGSizeMake(0, -1), 1, [UIColor colorWithWhite:0 alpha:.15].CGColor);
[image drawAtPoint:CGPointZero];
}
UIImage *resultImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return resultImage;
}
Finally, you can combine those functions to create an embossed image of your string. I put my final image into a UIImageView for easy testing.
- (void)viewDidLoad
{
[super viewDidLoad];
CGRect rect = self.imageView.bounds;
NSString *string = #"Reminders";
UIFont *font = [UIFont systemFontOfSize:33];
UIImage *interiorShadowImage = [self imageWithInteriorShadowAndString:string
font:font
textColor:[UIColor colorWithHue:0 saturation:.9 brightness:.7 alpha:1]
size:rect.size];
UIImage *finalImage = [self imageWithUpwardShadowAndImage:interiorShadowImage];
self.imageView.image = finalImage;
}
That just looks like a shadow around the text. You set it in IB in the same area where you set the text color - pick an appropriate color for the shadow and set how you want the shadow offset (in the example you posted, it looks like they set the shadow color to the same color as the text and offset it 0 horizontal and -1 vertical (which means one pixel up).
In code, the properties are set like this (assuming you have already set up a UILabel named, appropriately, "label":
label.shadowColor = [UIColor blackColor]; // Choose your color here - in the example
// posted, they probably chose a similar color
// to the text color and then set the alpha
// down around 0.7 or so so the shadow would be
// faint.
label.shadowOffset = CGSizeMake(0,-1); // First parameter is horizontal, second is vertical
You can configure your effect on the basis of this example

UIImagePNGRepresentation and masked images

I created a masked image using a function form an iphone blog:
UIImage *imgToSave = [self maskImage:[UIImage imageNamed:#"pic.jpg"] withMask:[UIImage imageNamed:#"sd-face-mask.png"]];
Looks good in a UIImageView
UIImageView *imgView = [[UIImageView alloc] initWithImage:imgToSave];
imgView.center = CGPointMake(160.0f, 140.0f);
[self.view addSubview:imgView];
UIImagePNGRepresentation to save to disk:
[UIImagePNGRepresentation(imgToSave) writeToFile:[self findUniqueSavePath] atomically:YES];
UIImagePNGRepresentation returns NSData of an image that looks different.
The output is inverse image mask.
The area that was cut out in the app is now visible in the file.
The area that was visible in the app is now removed. Visibility is opposite.
My mask is designed to remove everything but the face area in the picture. The UIImage looks right in the app but after I save it on disk, the file looks opposite. The face is removed but everything else this there.
Please let me know if you can help!
In quartz you cam mask either by an image mask (black let through and white blocks), or a normal image (white let through and black blocks) which is the opposite. It seems for some reason saving is treating the image mask as a normal image to mask with. One thought is to render to a bitmap context and then create an image to be saved from that.
I had the exact same issue, when I saved the file it was one way, but the image returned in memory was the exact opposite.
The culprit & the solution was UIImagePNGRepresentation(). It fixes the in-app image before saving it to disk, so I just inserted that function as the last step in creating the masked image and returning that.
This may not be the most elegant solution, but it works. I copied some code from my app and condensed it, not sure if this code below works as is, but if not, its close... maybe just some typos.
Enjoy. :)
// MyImageHelperObj.h
#interface MyImageHelperObj : NSObject
+ (UIImage *) createGrayScaleImage:(UIImage*)originalImage;
+ (UIImage *) createMaskedImageWithSize:(CGSize)newSize sourceImage:(UIImage *)sourceImage maskImage:(UIImage *)maskImage;
#end
// MyImageHelperObj.m
#import <QuartzCore/QuartzCore.h>
#import "MyImageHelperObj.h"
#implementation MyImageHelperObj
+ (UIImage *) createMaskedImageWithSize:(CGSize)newSize sourceImage:(UIImage *)sourceImage maskImage:(UIImage *)maskImage;
{
// create image size rect
CGRect newRect = CGRectZero;
newRect.size = newSize;
// draw source image
UIGraphicsBeginImageContextWithOptions(newRect.size, NO, 0.0f);
[sourceImage drawInRect:newRect];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
// draw mask image
[maskImage drawInRect:newRect blendMode:kCGBlendModeNormal alpha:1.0f];
maskImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
// create grayscale version of mask image to make the "image mask"
UIImage *grayScaleMaskImage = [MyImageHelperObj createGrayScaleImage:maskImage];
CGFloat width = CGImageGetWidth(grayScaleMaskImage.CGImage);
CGFloat height = CGImageGetHeight(grayScaleMaskImage.CGImage);
CGFloat bitsPerPixel = CGImageGetBitsPerPixel(grayScaleMaskImage.CGImage);
CGFloat bytesPerRow = CGImageGetBytesPerRow(grayScaleMaskImage.CGImage);
CGDataProviderRef providerRef = CGImageGetDataProvider(grayScaleMaskImage.CGImage);
CGImageRef imageMask = CGImageMaskCreate(width, height, 8, bitsPerPixel, bytesPerRow, providerRef, NULL, false);
CGImageRef maskedImage = CGImageCreateWithMask(newImage.CGImage, imageMask);
CGImageRelease(imageMask);
newImage = [UIImage imageWithCGImage:maskedImage];
CGImageRelease(maskedImage);
return [UIImage imageWithData:UIImagePNGRepresentation(newImage)];
}
+ (UIImage *) createGrayScaleImage:(UIImage*)originalImage;
{
//create gray device colorspace.
CGColorSpaceRef space = CGColorSpaceCreateDeviceGray();
//create 8-bit bimap context without alpha channel.
CGContextRef bitmapContext = CGBitmapContextCreate(NULL, originalImage.size.width, originalImage.size.height, 8, 0, space, kCGImageAlphaNone);
CGColorSpaceRelease(space);
//Draw image.
CGRect bounds = CGRectMake(0.0, 0.0, originalImage.size.width, originalImage.size.height);
CGContextDrawImage(bitmapContext, bounds, originalImage.CGImage);
//Get image from bimap context.
CGImageRef grayScaleImage = CGBitmapContextCreateImage(bitmapContext);
CGContextRelease(bitmapContext);
//image is inverted. UIImage inverts orientation while converting CGImage to UIImage.
UIImage* image = [UIImage imageWithCGImage:grayScaleImage];
CGImageRelease(grayScaleImage);
return image;
}
#end

How to create an image from a UIView / UIScrollView

I have an image in an UIScrollView, that can be scrolled and zoomed.
When the user presses a button, I want the code to create an image from whatever part of the UIScrollView is inside an area I specify with a CGRect.
I've seen code to crop UIImages, but I can't adapt it to do the same for a view, because it uses CGContextDrawImage.
Any thoughts?
Cheers,
Andre
I've managed to get it.
Here's my solution, based on a few different ones from the web:
- (UIImage *)imageByCropping:(UIScrollView *)imageToCrop toRect:(CGRect)rect
{
CGSize pageSize = rect.size;
UIGraphicsBeginImageContext(pageSize);
CGContextRef resizedContext = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(resizedContext, -imageToCrop.contentOffset.x, -imageToCrop.contentOffset.y);
[imageToCrop.layer renderInContext:resizedContext];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
which you call by using:
CGRect clippedRect = CGRectMake(0, 0, 320, 300);
picture.image = [self imageByCropping:myScrollView toRect:clippedRect];

How to get a color image in iPhone sdk

I want something as follows
UIImage *solid = [UIImage imageWithColor:[UIColor darkGrayColor]];
to create an image with respect to some color.
how to do it in iPhone sdk.
You can draw the color into a CGContext and then capture an image from it:
- (UIImage *)imageWithColor:(UIColor *)color andSize:(CGSize)size {
//Create a context of the appropriate size
UIGraphicsBeginImageContext(size);
CGContextRef currentContext = UIGraphicsGetCurrentContext();
//Build a rect of appropriate size at origin 0,0
CGRect fillRect = CGRectMake(0,0,size.width,size.height);
//Set the fill color
CGContextSetFillColorWithColor(currentContext, color.CGColor);
//Fill the color
CGContextFillRect(currentContext, fillRect);
//Snap the picture and close the context
UIImage *retval = UIGraphicsGetImageFromCurrentImageContext(void);
UIGraphicsEndImageContext();
return retval;
}
If you're just trying to create a solid rectangle of colour why not just do something like
UIView *solid = [[UIView alloc] initWithFrame:someFrame];
solid.backgroundColor = [UIColor greyColor];
And then add the view to whatever subview you want to show the solid colour.
(That is, of course only if that's what you're trying to achieve. Maybe you aren't)