Image rotation In IOS - ios

I am using Xcode 7.3 and ojective-c one of my application when I am converting the camera image into base64 then image will be rotation 90 degree left I try so many method to fix this issue but did not working any one.
Below are the code:
NSString *data64URLString = [NSString stringWithFormat:#"data:image/png;base64,%#", [UIImageJPEGRepresentation(image, 0) base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength]];
I try all the orientation by this ways but it's not working:
CGImageRef cgRef = image.CGImage;
image = [[UIImage alloc] initWithCGImage:cgRef scale:1.0 orientation:UIImageOrientationDownMirrored];
UIImage *originalImage = image;

Try this code:
- (UIImage *)imageRotatedByDegrees:(UIImage*)oldImage deg:(CGFloat)degrees
{
//Calculate the size of the rotated view's containing box for our drawing space
UIView *rotatedViewBox = [[UIView alloc] initWithFrame:CGRectMake(0,0,oldImage.size.width, oldImage.size.height)];
CGAffineTransform t = CGAffineTransformMakeRotation(degrees * M_PI / 180);
rotatedViewBox.transform = t;
CGSize rotatedSize = rotatedViewBox.frame.size;
//Create the bitmap context
UIGraphicsBeginImageContext(rotatedSize);
CGContextRef bitmap = UIGraphicsGetCurrentContext();
//Move the origin to the middle of the image so we will rotate and scale around the center.
CGContextTranslateCTM(bitmap, rotatedSize.width/2, rotatedSize.height/2);
//Rotate the image context
CGContextRotateCTM(bitmap, (degrees * M_PI / 180));
//Now, draw the rotated/scaled image into the context
CGContextScaleCTM(bitmap, 1.0, -1.0);
CGContextDrawImage(bitmap, CGRectMake(-oldImage.size.width / 2, -oldImage.size.height / 2, oldImage.size.width, oldImage.size.height), [oldImage CGImage]);
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}

As per this thread, PNG format has a known issue with rotation, I would suggest you to try UIImageJPEGRepresentation with data:image/jpg; instead of data:image/png;. This way it will probably set the rotation flag.
Hope it helps!

You can save to your app and get image from memory to view with code:
- (UIImage *)finishSavePhotoWithImagePickerController:(NSDictionary *()info {
UIImage *editedImage = (UIImage *) [info objectForKey:UIImagePickerControllerEditedImage];
UIImage *originalImage = (UIImage *) [info objectForKey:UIImagePickerControllerOriginalImage];
if (editedImage) {
imageToSave = editedImage;
} else {
imageToSave = originalImage;
}
NSData *imageData = UIImageJPEGRepresentation(imageToSave, 1.0);
[imageData writeToFile:#"yourFilePath" options:NSDataWritingFileProtectionNone error:nil];
UIImage *showImage = [[UIImage alloc] initWithContentsOfFile:#"yourFilePath"];
return showImage;
}

Related

HOW TO ROTATE IMAGE in circular path

I want to rotate image (arrow) in circular path in coreGraphics like this image. in circular path.
input image:
output after rotation:
This will return rotated image
- (UIImage *)rotateImage:(UIImage *)image onDegrees:(float)degrees
{
CGFloat rads = M_PI * degrees / 180;
float newSide = MAX([image size].width, [image size].height);
CGSize size = CGSizeMake(image.size.width, newSide);
UIGraphicsBeginImageContext(size);
CGContextRef ctx = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(ctx, image.size.width, newSide/2);
CGContextRotateCTM(ctx, rads);
CGRect r = CGRectMake(0,-[image size].height/2,image.size.width,image. size.height);
[image drawInRect:r];
UIImage *i = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return i;
}
UIImage *arrowRotated180 = [self rotateImage:[UIImage imageNamed:#"arrowImage"] onDegrees:180];
UIImage *arrowRotated90 = [self rotateImage:[UIImage imageNamed:#"arrowImage"] onDegrees:90];
Put three images and rotate 2 & 3 image as follow.
imageview2.transform = CGAffineTransformMakeRotation(M_PI/4);
imageview3.transform = CGAffineTransformMakeRotation(M_PI/2);
Hope this will help you...
try UIcollectionview it worked my case .

Cropped iOS Image comes back too large

Been trying to fix this problem all day to no avail.
Pretty much, I'm taking a screenshot of the view, then trying to crop out the first 50px and a footer. Problem is that when I do this, the result is a little blowed up, and quality is lost. Here's what I wrote, which I think conforms to retina.
-(UIImage *)takeSnapShotAndReturn{
//Take screenshot of whole view
if([[UIScreen mainScreen] respondsToSelector:#selector(scale)]){
UIGraphicsBeginImageContextWithOptions(self.view.bounds.size,NO,[UIScreen mainScreen].scale);
}
else{
UIGraphicsBeginImageContext(self.view.window.bounds.size);
}
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
combinedImage = [self cropOutArea:image withRectangle:CGRectMake(0, 50, 320, 467)];
UIImageWriteToSavedPhotosAlbum(combinedImage, nil, nil, nil);
UIGraphicsEndImageContext();
return image;
}
-(UIImage *)cropOutArea:(UIImage*)image withRectangle:(CGRect)rectangle{
if(image.scale > 1){
rectangle = CGRectMake(rectangle.origin.x * image.scale,
rectangle.origin.y * image.scale,
rectangle.size.width * image.scale,
rectangle.size.height * image.scale);
}
CGImageRef imageRef = CGImageCreateWithImageInRect(image.CGImage, rectangle);
UIImage *result = [UIImage imageWithCGImage:imageRef scale:image.scale orientation:image.imageOrientation];
CGImageRelease(imageRef);
return result;
}
I find cropping extremely confusing!
I'm not sure EXACTLY what you're trying to do, but this may be it .....
-(UIImage *)simplishTopCropAndTo640:(UIImage *)fromImage
// moderately optimised!
{
float shortDimension = fminf(fromImage.size.width, fromImage.size.height);
// 1.use CGImageCreateWithImageInRect to take only the top square...
// 2. use drawInRect (or CGContextDrawImage, same) to scale...
CGRect topSquareOfOriginalRect =
CGRectMake(0,0, shortDimension,shortDimension);
// NOT fromImage.size.width,fromImage.size.width);
CGImageRef topSquareIR = CGImageCreateWithImageInRect(
fromImage.CGImage, topSquareOfOriginalRect);
CGSize size = CGSizeMake( 640,640 );
CGRect sized = CGRectMake(0.0f, 0.0f, size.width, size.height);
UIGraphicsBeginImageContextWithOptions(size, NO, 0.0f);
CGContextRef cc = UIGraphicsGetCurrentContext();
CGContextSetInterpolationQuality(cc, kCGInterpolationLow);
CGContextTranslateCTM(cc, 0, size.height);
CGContextScaleCTM(cc, 1.0, -1.0);
CGContextDrawImage(cc, sized, topSquareIR );
// arguably, those three lines more simply...
//[[UIImage imageWithCGImage:topSquareIR] drawInRect:sized];
CGImageRelease(topSquareIR);
UIImage *result = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
result =
[UIImage imageWithCGImage:result.CGImage
scale:result.scale
orientation: fromImage.imageOrientation];
//consider...something like...
//[UIImage imageWithCGImage:cgimg
// scale:3 orientation:fromImage.imageOrientation];
return result;
}
Consider also this valuable category .....
-(UIImage *)ordinaryCrop:(CGRect)toRect
{
// crops any image, to any rect. you can't beat that
CGImageRef imageRef = CGImageCreateWithImageInRect([self CGImage], toRect);
UIImage *cropped = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
return cropped;
}
Finally don't forget this if you're using the camera "the most useful code in the universe!" iOS UIImagePickerController result image orientation after upload
Hope it helps somehow
Try setting this BOOL property before releasing result in cropOutArea.
result.layer.masksToBounds = YES

drawInRect does not read / preserve UIImageView transform

I encountered a problem when I pinch, pan or rotate a UIImageview in drawInRect, the transform is not being preserved.
How can I preserve the transform in drawInRect?
I tried this but no go :(
- (UIImage*) combineImage:(UIImageView *)selectedImage withOverlay:(UIImageView *)overlayImage
{
/* Identify the region that needs to be cropped */
CGRect viewForImgFrame = self.viewForImg.frame;
NSLog(#"view %#", NSStringFromCGRect(viewForImgFrame));
NSLog(#"selectedImage Img value %#",selectedImage);
NSLog(#"overlayImage Img value %#",overlayImage);
CGSize newImageSize =self.viewForImg.frame.size;
NSLog(#"CGSize %#",NSStringFromCGSize(newImageSize));
UIGraphicsBeginImageContextWithOptions(newImageSize, NO, 0.0); //retina res
//[self.viewForImg.layer renderInContext:UIGraphicsGetCurrentContext()];
[selectedImage.image drawInRect:CGRectMake(0, 0, selectedImage.frame.size.width, selectedImage.frame.size.height)];
CGContextConcatCTM(UIGraphicsGetCurrentContext(), overlayImage.transform);
[overlayImage.image drawInRect:CGRectMake(overlayImage.frame.origin.x, overlayImage.frame.origin.y, overlayImage.frame.size.width, overlayImage.frame.size.height)];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
NSData *imgData = UIImageJPEGRepresentation(image, 0.9); //UIImagePNGRepresentation ( image ); // get JPEG representation
UIImage * imagePNG = [UIImage imageWithData:imgData]; // wrap UIImage around PNG representation
UIGraphicsEndImageContext();
return imagePNG;
}
Any comments are greatly appreciated.
you need to try
CGRectApplyAffineTransform(<#CGRect rect#>, <#CGAffineTransform t#>)
your code should be like
CGContextConcatCTM(UIGraphicsGetCurrentContext(), overlayImage.transform);
CGRect rect = CGRectMake(overlayImage.frame.origin.x, overlayImage.frame.origin.y, overlayImage.frame.size.width, overlayImage.frame.size.height);
CGRect transformedRect = CGRectApplyAffineTransform(rect, overlayImage.transform);
[overlayImage.image drawInRect:transformedRect];
It turned out that the AutoresizingMask changed rect size
[slider setAutoresizingMask:UIViewAutoresizingNone];

Convert a UIImage to a CIImage to crop to a CGRect. AVFoundation

So I have a UIImage which I want to crop. I looked and found imageByCroppingToRect method for CIImage. So, I converted the data to CIImage instead of UIImage, crop it using the specified method and then convert the resulting CIImage to UIImage and then display it in a UIImageView.
My code is
NSData *data = [[NSData alloc]initWithData:[def objectForKey:#"imageData"]];
//UIImage *normalImage = [[UIImage alloc]initWithData:data];
CIImage *originalImage = [CIImage imageWithData:data];
[originalImage imageByCroppingToRect:CGRectMake(10, 72, 300, 300)];
self.imageView.image = [UIImage imageWithCIImage:originalImage];
The problem is the image gets rotated by 90 degrees and I am not sure if it is being cropped. This image is captured using the device's camera. I use AVFoundation to access the camera. My session preset is AVCaptureSessionPresetPhoto. I think this is why I get the zooming.
CGRect rect = CGRectMake(10, 72, 300, 300);
CGImageRef imref = CGImageCreateWithImageInRect([yourOriginalImage CGImage], rect);
UIImage *newSubImage = [UIImage imageWithCGImage:imref];
try this. may help u.
EDIT:
Firstly fix your image orientation:
refs : https://github.com/j3r3miah/mapmatic-ios/blob/master/Mapmatic/UIImage+FixOrientation.m
then use above code to crop the Image to Specified Rect.
Not really an answer to your question, but an answer to your problem
https://github.com/mbcharbonneau/UIImage-Categories
especially this file : https://github.com/mbcharbonneau/UIImage-Categories/blob/master/UIImage%2BResize.m
- (UIImage *)croppedImage:(CGRect)bounds {
CGFloat scale = MAX(self.scale, 1.0f);
CGRect scaledBounds = CGRectMake(bounds.origin.x * scale, bounds.origin.y * scale, bounds.size.width * scale, bounds.size.height * scale);
CGImageRef imageRef = CGImageCreateWithImageInRect([self CGImage], scaledBounds);
UIImage *croppedImage = [UIImage imageWithCGImage:imageRef scale:self.scale orientation:UIImageOrientationUp];
CGImageRelease(imageRef);
return croppedImage;
}
you will find there all you need to crop your image

Rotating a UIImageView by angles

I want to rotate a UIImageView with the press of a button. I am using this code:
#import "UIImage-Extensions.h"
UIImage *rotatedImage = [SplashItGroupPicker.image imageRotatedByDegrees:360/arrayCount];
SplashItGroupPicker.image = rotatedImage;
and in "UIImage-Extensions.h" i have:
#interface UIImage (CS_Extensions)
- (UIImage *)imageRotatedByRadians:(CGFloat)radians;
- (UIImage *)imageRotatedByDegrees:(CGFloat)degrees;
and in the .m:
- (UIImage *)imageRotatedByRadians:(CGFloat)radians
{
return [self imageRotatedByDegrees:RadiansToDegrees(radians)];
}
- (UIImage *)imageRotatedByDegrees:(CGFloat)degrees
{
// calculate the size of the rotated view's containing box for our drawing space
UIView *rotatedViewBox = [[UIView alloc] initWithFrame:CGRectMake(0,0,self.size.width, self.size.height)];
CGAffineTransform t = CGAffineTransformMakeRotation(DegreesToRadians(degrees));
rotatedViewBox.transform = t;
CGSize rotatedSize = rotatedViewBox.frame.size;
// Create the bitmap context
UIGraphicsBeginImageContext(rotatedSize);
CGContextRef bitmap = UIGraphicsGetCurrentContext();
// Move the origin to the middle of the image so we will rotate and scale around the center.
CGContextTranslateCTM(bitmap, rotatedSize.width/2, rotatedSize.height/2);
// // Rotate the image context
CGContextRotateCTM(bitmap, DegreesToRadians(degrees));
// Now, draw the rotated/scaled image into the context
CGContextScaleCTM(bitmap, 1.0, -1.0);
CGContextDrawImage(bitmap, CGRectMake(-self.size.width / 2, -self.size.height / 2, self.size.width, self.size.height), [self CGImage]);
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
...the rotation works fine, but when the image is rotated, the image also gets smaller and I can't understand why. Any ideas?
Here's a guess, is this only happening on Retina screens? Whenever saving a UIImage from a graphics context, you need to make sure the scale is correct. This is how I have done it:
CGFloat scale = [[UIScreen mainScreen] scale];
CGSize size = CGSizeMake(rotatedViewBox.frame.size.width * scale, rotatedViewBox.frame.size.height * scale);
UIGraphicsBeginImageContext( size );
/* Do your image manipulations here */
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
// overwrite the image with one that has the correct scale set
newImage = [UIImage imageWithCGImage:newImage.CGImage scale:scale orientation:newImage.imageOrientation];
Using Kekoa's snippet (thanks a ton), I was able to get a working rotateImage function that works on retina devices based on Apples rotateImage code:
- (UIImage *)imageRotatedByDegrees:(CGFloat)degrees {
CGFloat radians = DegreesToRadians(degrees);
UIView *rotatedViewBox = [[UIView alloc] initWithFrame:CGRectMake(0,0, self.size.width, self.size.height)];
CGAffineTransform t = CGAffineTransformMakeRotation(radians);
rotatedViewBox.transform = t;
CGSize rotatedSize = rotatedViewBox.frame.size;
UIGraphicsBeginImageContextWithOptions(rotatedSize, NO, [[UIScreen mainScreen] scale]);
CGContextRef bitmap = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(bitmap, rotatedSize.width / 2, rotatedSize.height / 2);
CGContextRotateCTM(bitmap, radians);
CGContextScaleCTM(bitmap, 1.0, -1.0);
CGContextDrawImage(bitmap, CGRectMake(-self.size.width / 2, -self.size.height / 2 , self.size.width, self.size.height), self.CGImage );
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
There is no need to UIGraphicsGetImageFromCurrentImageContext. its a way to get screenshot of desired portion of mainscreen. so the result image quality affected. the only way to get Rotated Image is...
first rotate your image view by(if you want to show rotated view)
[mainImgV setTransform:CGAffineTransformRotate(mainImgV.transform, M_PI)];
it will rotate your imageview.
now you will take this rotated image by these lines.(you can call these lines without rotate imgaeview also.)
CGImageRef cgRef = mainImgV.image.CGImage;
newImage = [[UIImage alloc] initWithCGImage:cgRef scale:1.0 orientation:UIImageOrientationDown];
there is no need to save or take screenshot or compromise bad quality image. just enjoy coding.

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