I have the self.view, but I only want to capture 300x320 of it.
got this code:
UIGraphicsBeginImageContext(self.view.bounds.size);
[self.view.window.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);
UIImage * imgPrintScreen = [[UIImage alloc]init];
imgPrintScreen = viewImage;
What do I need to change here in order to do so?
Thanks allot!
Just change the size that you want to capture, instead of using the entire bounds, use the size you want. The render will start at the origin of the view and be clipped when it falls outside the bounds. If you need to change where the view is actually clipped, simply translate the context after starting the image context:
UIGraphicsBeginImageContextWithOptions(CGSizeMake(300, 320), YES, 0.);
[self.view.window.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
If your view was, for example, 600x320 and you wanted to capture the middle 300 points in width, you'd translate the context 150 points to the left:
UIGraphicsBeginImageContextWithOptions(CGSizeMake(300, 320), YES, 0.);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(context, -150.f, 0.f);
[self.view.window.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
Related
I want to convert UIView to UIImage, in which the view is in background and when I checked view hierarchy, it is there as white space, probably it wont get loaded..
What I wanted to do is load the view into memory and convert into image.
you just need to initialize your view with your required frame and then pass to below code as targetView. Initialize your view before you call screen capture method like below
UIView *targetView = [[UIView alloc]initWithFrame:CGRectMake(0, 0, 320, 568)]; //Initilization
UIImage *capturedImage = [self captureScreen:targetView]; //Call method
- (UIImage *)captureScreen:(UIView*)targetView
{
UIView* captureView = targetView;
UIGraphicsBeginImageContextWithOptions(captureView.bounds.size, captureView.opaque, 0.0);
[captureView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage * screenshot = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
CGRect cropRect = CGRectMake(0 ,0 ,captureView.frame.size.width ,captureView.frame.size.height);
UIGraphicsBeginImageContextWithOptions(cropRect.size, captureView.opaque, 1.2f);
[screenshot drawInRect:cropRect];
UIImage * customScreenShot = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return customScreenShot;
}
Use this:
- (UIImage*)snapShot:(UIView*)myView {
UIGraphicsBeginImageContext(myView.frame.size);
[myView.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return viewImage;
}
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();
I have a parent UIView which contains 3 subviews, here i have one UIButton to take snap of the whole view. i have done this using
UIGraphicsBeginImageContext(CGSizeMake(320,480));
CGContextRef context = UIGraphicsGetCurrentContext();
UIImage *screenShot = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
[self.view.layer renderInContext:context];
here i need to capture only the 1st subview which name is subview1. how can i do this?
Capture SubView like this:
UIGraphicsBeginImageContext(subview1.size);
[subview1.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *screenShot = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
I have an App that takes a screenshot of a UIImageView with the following code:
-(IBAction) screenShot: (id) sender{
UIGraphicsBeginImageContext(sshot.frame.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(viewImage,nil, nil, nil);
}
This works well but I need to be able to position where I take the screenshot basically I need to grad only a third of the screen (center portion). I tried using
UIGraphicsBeginImageContext(CGSize 150,150);
But have found that every thing is taken from 0,0 coordinates, has anyone any idea how to position this correctly.
Well the screenshot is taken from a canvas you draw.
So instead of drawing your layer in the whole context, with a reference to top left corner, you will draw it where you want to take the screenshot....
//first we will make an UIImage from your view
UIGraphicsBeginImageContext(self.view.bounds.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *sourceImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
//now we will position the image, X/Y away from top left corner to get the portion we want
UIGraphicsBeginImageContext(sshot.frame.size);
[sourceImage drawAtPoint:CGPointMake(-50, -100)];
UIImage *croppedImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(croppedImage,nil, nil, nil);
From this
UIGraphicsBeginImageContext(sshot.frame.size);
CGContextRef c = UIGraphicsGetCurrentContext();
CGContextTranslateCTM(c, 150, 150); // <-- shift everything up to required position when drawing.
[self.view.layer renderInContext:c];
UIImage* viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);
Use this method to crop if u have image with specfic rect to crop:
-(UIImage *)cropImage:(UIImage *)image rect:(CGRect)cropRect
{
CGImageRef imageRef = CGImageCreateWithImageInRect([image CGImage], cropRect);
UIImage *img = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
return img;
}
Use like this:
UIImage *img = [self cropImage:viewImage rect:CGRectMake(150,150,100,100)]; //example
If you like you can refer this code.
In this example you can get the image covered by the rect from any position and any zoom scale.
Happy Coding :)
Some extracted code for reference is as below
Main function or code used to crop the photo
- (UIImage *) croppedPhoto
{
CGFloat ox = self.scrollView.contentOffset.x;
CGFloat oy = self.scrollView.contentOffset.y;
CGFloat zoomScale = self.scrollView.zoomScale;
CGFloat cx = (ox + self.cropRectangleButton.frame.origin.x + 15.0f) * 2.0f / zoomScale;
CGFloat cy = (oy + self.cropRectangleButton.frame.origin.y + 15.0f) * 2.0f / zoomScale;
CGFloat cw = 300.0f / zoomScale;
CGFloat ch = 300.0f / zoomScale;
CGRect cropRect = CGRectMake(cx, cy, cw, ch);
NSLog(#"---------- cropRect: %#", NSStringFromCGRect(cropRect));
NSLog(#"--- self.photo.size: %#", NSStringFromCGSize(self.photo.size));
CGImageRef imageRef = CGImageCreateWithImageInRect([self.photo CGImage], cropRect);
UIImage *result = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
NSLog(#"------- result.size: %#", NSStringFromCGSize(result.size));
return result;
}
The details how to use the example is given here.
Enjoy Coding :)
In mac osx (cocoa), It is very easy to make a blank image of a specific size and draw to it off screen:
NSImage* image = [[NSImage alloc] initWithSize:NSMakeSize(64,64)];
[image lockFocus];
/* drawing code here */
[image unlockFocus];
However, in iOS (cocoa touch) there does not seem to be equivalent calls for UIImage. I want to use UIImage (or some other equivalent class) to do the same thing. That is, I want to make an explicitly size, initially empty image to which I can draw using calls like UIRectFill(...) and [UIBezierPath stroke].
How would I do this?
CoreGraphics is needed here, as UIImage does not have high level functions like what you explained..
UIGraphicsBeginImageContext(CGSizeMake(64,64));
CGContextRef context = UIGraphicsGetCurrentContext();
// drawing code here (using context)
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
You can do that as follows:
UIGraphicsBeginImageContext(CGSizeMake(64, 64));
//Drawing code here
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
Here is Apple's Graphics and Drawing reference.
Something like this:
UIGraphicsBeginImageContextWithOptions(mySize, NO, 0.0f);
CGContextRef context = UIGraphicsGetCurrentContext();
UIGraphicsPushContext(context);
[myImage drawInRect:myImageRect];
[myText drawAtPoint:myOrigin withFont:myFont];
UIGraphicsPopContext();
UIImage *myNewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();