I've got an image that I need crop. To do this, I wanted to use the contentMode (set it to Top/TopLeft instead of Aspect Fit) but when I'm doing this, the image go back to it's real size (and not the size I gave to it). So my question is :
How to crop the bottom of my image retaining its size ?
Thanks a lot.
May be you have to set the rect for the imageView
imageView is the instance of UIImageView
Let the rectangle to be cropped is croppedRect
CGImageRef imageRef = CGImageCreateWithImageInRect([imageView.image CGImage], croppedRect);
[imageView setImage:[UIImage imageWithCGImage:imageRef]];
CGImageRelease(imageRef);
Related
I added a uiview as a subview on a view controller programmatically (called contentView). I also added an image on that uiview programmatically. Every time I run the app on the iPad the image is stretched! How do I fix the image so that it fits the iPad screen but doesn't stretch the image? I know the drawInRect is what is stretching the image. So how do I fix that?
Here is my code:
UIGraphicsBeginImageContextWithOptions(self.contentView.bounds.size, self.contentView.opaque, 0.0);
[[UIImage imageNamed:#"menu image 2.JPG"] drawInRect:self.contentView.bounds];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
[self.contentView addSubview:imageView];
UIImageView has a property called contentMode which determines how the image layout is handled in the view context. contentMode is of type UIViewContentMode.
The default value is UIViewContentModeScaleToFill which stretches the image without respecting the aspect ratio. I am assuming it is the changing aspect ratio that is causing the issue.
If you wish to scale the image, but keep the aspect ratio, you have two options:
UIViewContentModeScaleAspectFit: This will show the image scaled to fill the view, but not clip any contents (if the aspect ratio doesn't match view size, it will show either horizontal or vertical bands)
UIViewContentModeScaleAspectFill: This will scale the image to fill the view entirely, without any bands - this will result in content being clipped if the image ratio doesn't match the view ratio.
To set the contentMode on the image view in Objective-C, use the following syntax:
UIImage *image = [UIImage imageNamed:#"menu image 2.JPG"];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
imageView.contentMode = UIViewContentModeScaleAspectFill;
...
You should not need to use the custom context drawing for this to work anymore (thanks to Losiowaty for asking me about this).
Change code as below
UIImage *image = [UIImage imageNamed:#"menu image 2.JPG"];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
imageView.contentMode = UIViewContentModeScaleAspectFit;
[self.contentView addSubview:imageView];
I guess your self.contentView.bounds is not having the same aspect ratio as your menu image 2.JPG . For an experiment, please try looking at the menu image 2.JPG's resolution. For example if it is 300x150, it's aspect ratio is (300/150 = 2:1). Set your self.contentView.bounds to this aspect ratio and draw the image and check the results. It will not stretch.
Please add this Single Line of code in your project
yourImage .contentMode = UIViewContentModeScaleAspectFit;
My UIImageView with constant Width*Height is 100*100 on UIView, But image i want to show in this UIImageView is 25*25 (original dimension ).
I don't want to stretch image. i try UIImageView ContentMode property but did't work.
This i don't want.tried sizeToFit and aspectCenter mode.
I need following result,For small images
How to do that(With out stretching original image dimension and constant UIImageView dimension).What will be case if image is bigger than UIImageView ? Thanks in advance.
Try this
(Objective-C):
imageView.contentMode = UIViewContentModeCenter;
(Swift):
imageView.contentMode = UIViewContentMode.Center;
Call - sizeToFit
That should do exactly what you need.
https://developer.apple.com/library/ios/documentation/UIKit/Reference/UIView_Class/index.html#//apple_ref/occ/instm/UIView/sizeToFit
you should try this
imageView.contentMode = UIViewContentModeScaleAspectFit;
no matter image is small or big it will scale the image.
if you don't want to stretch image than you have to resize UIImageView to image size
You can obtain image size from UIImage.
for eg
UIImage *image = [UIImage imageNamed:#"imageName"];
float imgHeight = image.size.height;
float imgWidth = image.size.width;
I'm trying to resize the UIImage
Before the UIImage:
After this code and UIImage:
UIGraphicsBeginImageContext (CGPointMake(155,139));
[currentImageView.image drawInRect:CGRectMake(0,0,155,139)];
currentImageView.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSLog(#"get size : %#",NSStringFromCGSize(currentImageView.image.size));
NSLog: get size : {155,139}
Last, I try to restore the size by this code. but its blurry.
UIGraphicsBeginImageContext (OriginalSize);
[currentImageView.image drawInRect:CGRectMake(0,0,OriginalSize.width,OriginalSize.height)];
currentImageView.image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSLog(#"get size : %#",NSStringFromCGSize(cnurrentImageView.image.size));
NSLog: get size : {1024,352}
What happened?
Have any suggestions and advice?
You are making two mistakes,
1.Reducing the image size and setting it to a larger size imageView,
this can be fixed with the code,
imageView.contentMode = UIViewContentModeScaleAspectFit;
2.You have resize the original image to a smaller size, then
resizing the smaller image to original size, this will stretch the
image.
FOR 1 : first step,
You can use this code so that the image quality doesn't loose:
Instead of
UIGraphicsBeginImageContext
Use
UIGraphicsBeginImageContextWithOptions(currentImageView.frame.size, NO, 0);
as the size you want is smaller and the imageview is larger so you also need to set
YourimageView.contentMode = UIViewContentModeScaleAspectFit;
For Second Step :
Use original image to resize it.
This question already has answers here:
The simplest way to resize an UIImage?
(34 answers)
Closed 9 years ago.
I've created a UIImageView which contains an image with a high resolution. The problem is that the resolution of that image is too high to put into the imageView. The size of the imageView is 92 x 91 (so it's small). It contains an UIImage, whose resolution is too high so it looks ugly in the UIImageView.
So how can I reduce the resolution of that UIImage?
My code for the UIImageView:
UIImageView *myImageView = [[UIImageView alloc] initWithImage:[UIImage imageWithContentsOfFile:pngFilePath]];
myImageView.frame = CGRectMake(212.0, 27, 92,91);
have a look at this
https://stackoverflow.com/a/2658801
This will help you to resize your image according to your need
Add method to your code and call like this
UIImage *myImage =[UIImage imageWithContentsOfFile:pngFilePath];
UIImage *newImage =[UIImage imageWithImage:myImage scaledToSize:CGSizeMake(92,91)];
You can resize an image using this method that returns a resized image :
-(UIImage *)imageWithImage:(UIImage *)image scaledToSize:(CGSize)newSize {
UIGraphicsBeginImageContextWithOptions(newSize, NO, 0.0);
// Here pass new size you need
[image drawInRect:CGRectMake(0, 0, newSize.width, newSize.height)];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
Hope it helps you.
try with this
myImageView.contentMode = UIViewContentModeScaleToFill;
You need to downsize the image, which will reduce the resolution, make it easier to store. I actually wrote a class (building on some stuff from SO) that does just that. It's on my github, take a look:
https://github.com/pavlovonline/UIImageResizer
the main method is
-(UIImage*)resizeImage:(UIImage*)image toSize:(CGFloat)size
so you give this method the size to which you want to downsize your image. If the height is greater than the width, it will auto-calculate the middle and give you a perfectly centered square. Same for width being greater than height. If you need an image that is not square, make your own adjustments.
so you'll get back a downsized UIImage which you can then put into your UIImageView. Save some memory too.
I have one UIImageView. Its content mode is set to AspectFit.
[imageView setContentMode:UIViewContentModeScaleAspectFit].
I need to crop a subImage from this image. This is the code which crops the image:
CGImageRef imageRef = CGImageCreateWithImageInRect([imageView.image CGImage], customRect);
UIImage *cropped = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
where customRect is the rectangle from which I need to crop the image.
This is how I calculate it:
CGRect customRect = CGRectMake((cropView.frame.origin.x/xFactor),
(cropView.frame.origin.y/yFactor),
(cropView.frame.size.width/xFactor),
(cropView.frame.size.height/yFactor));
The problem comes in cropping. CGImageCreateWithImageInRect crops the given area according to the actual image size which, in some cases, is larger than the image view size. I tried using other approaches such as UIGraphics:getImageFromCurrentImageContext but these do not keep the image quality as much as it degrades them.