Capturing screenshot in iphone? - iphone

I want to take screenshot programatically. So that i write code for it like,
CGContextRef context = [self createBitmapContextOfSize:self.frame.size];
//not sure why this is necessary...image renders upside-down and mirrored
CGAffineTransform flipVertical = CGAffineTransformMake(1, 0, 0, -1, 0, self.frame.size.height);
CGContextConcatCTM(context, flipVertical);
[self.layer renderInContext:context];
CGImageRef cgImage = CGBitmapContextCreateImage(context);
UIImage* background = [UIImage imageWithCGImage: cgImage];
CGImageRelease(cgImage);
self.currentScreen = background;
Here all code is in custom UIView of UIViewController. Now when i play UIImageView png sequence animation on UIView, then i didn't get updated changes in UIImageView which is subview of custom UIView, why? I got only result is UIImageView with first UIImage.
Basically i need to create an video of my game play like talking tom application.

Take the screenshot of your ImageView with something like this:
[[[yourImageView layer] presentationLayer] renderInContext:context];
Use NSTimer for calling that getScreenshot function.
Hope this helps

you should probably take a look at AVFoundation and specifically AVAssetWriter as a way of creating videos of your screen content.

Following code is use for the capture the image into the iPhone for that following code to be use.
CGRect rect = CGRectMake(0.0, 0.0,self.view.frame.size.width,self.view.frame.size.height-44);
NSValue *rectObj = [NSValue valueWithCGRect:rect];
CGRect rectRestored = [rectObj CGRectValue];
UIGraphicsBeginImageContext(CGSizeMake(rectRestored.size.width, rectRestored.size.height-44));
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);
Also store the image into the gallery.

Related

How to take a screenshot programmatically in iOS?

I have a UIView that uses both UIKit control and OpenGL. I'd like to get a screenshot of that view programatically.
If I use UIGraphicsGetImageFromCurrentImageContext(), the OpenGL content is blank;
If I use the glReadPixels(...) method, the UIKit content is blank;
I'm confused as how to take a complete screenshot.
Thank you!
use following code to take screen shot
-(UIImage *) screenshot
{
CGRect rect;
rect=CGRectMake(0, 0, 320, 480);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context=UIGraphicsGetCurrentContext();
[self.view.layer renderInContext:context];
UIImage *image=UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
-(UIImage *) screenshot
{
CGImageRef UIGetScreenImage(void);
CGImageRef screen = UIGetScreenImage();
UIImage* screenImage = [UIImage imageWithCGImage:screen];
CGImageRelease(screen); // you need to call this.
return screenImage;
}
Well, there are few ways of capturing the iPhone screen programmatically
Using UIKIT http://developer.apple.com/library/ios/#qa/qa1703/_index.html
Using AVFoundation framework http://developer.apple.com/library/ios/#qa/qa1702/_index.html
Using OpenGL ES
http://developer.apple.com/library/ios/#qa/qa1704/_index.html
Starting from iOS 7 you can also use Why does my programmatically created screenshot look so bad on iOS 7?
Using UIWindow
CGRect screenRect = [[UIScreen mainScreen] bounds];
UIGraphicsBeginImageContext(screenRect.size);
CGContextRef ctx = UIGraphicsGetCurrentContext();
[[UIColor blackColor] set];
CGContextFillRect(ctx, screenRect);
[self.window.layer renderInContext:ctx];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
Using UIView
UIGraphicsBeginImageContext(self.view.frame.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viImage=UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
Out of these 6 options, I found the first option very convenient for copy-pasting and for applying level of compression as 1st method gives the image with true pixel data. I also like option 4, as the API comes with SDK.
You get result Uiimage without lose quality of image
- (UIImage *)captureView:(UIView *)view {
UIGraphicsBeginImageContextWithOptions(view.bounds.size, view.opaque, 0.0);
[view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage * img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return img;
}
UIGraphicsBeginImageContext(self.view.bounds.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
NSData *data = [UIImagePNGRepresentation(image) retain];
UImage *screenShot = [UIImage imageWithData:data];
You know where the OpenGL content is located in your view. So it should be easy to copy the result of glReadPixels into the snapshot of the UIKit.
maybe.. can you use something from here
- https://stackoverflow.com/questions/12413460/cocos2d-2-0-screenshots-on-ios-6
and here...
Why is glReadPixels() failing in this code in iOS 6.0?
Here is how you can take a simple screenshot programmatically of a UIImage. If you want it for any other object substitute the UIImage with it.
In the .h file add NSData *Data; then in your .m file add this to your code
UIGraphicsBeginImageContext(self.view.frame.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *attachimage = [[UIImage alloc]initWithData:Data];
UIImage *viImage=UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
attachimage = viImage;
UIImageWriteToSavedPhotosAlbum(viImage, nil, nil, nil);

Xcode 4.3 How do I save a region of my app screen?

I am creating a native app on Xcode 4.3 and deploying to target iOS 5. The app is a basically a greeting card creator. I am having trouble figuring out how to save a portion of the screen from within the app.
What I want to do is this:
I am offering the user a button, that says "e-mail". when they click the button, the app should 'save' their card as an image and then 'paste' that into an email body.
The reason this is different than other answers on this website is that the area I want to save is made up of 4 'elements'. There is a background graphic that is the tilted card background, then there is a text field where users can type a message and then next to that is a picture area where they can choose their own picture to put on the card.
Here is a photo of what I am talking about:
http://marklopezdesigns.com/mydownloadz!/screenshotCard3.png
How do I save a 'composite' high res of these?
And then how do I get that into an email body message?
The reason i am asking how to 'save' it is because I want to be able to offer users another button that says "save to camera roll" and "send as message". I figure if I can understand how to save this high-res to a variable, then I should be off and running.
Thanks in advance for the help.
========
Here's the solution below
========
...so after a bit of fiddling. Finally got what I wanted. Here's the codebase I have in my method that fires upon touch of the "Save to Album" button:
- (IBAction)savePhoto{
CGRect rect;
rect = CGRectMake(11,50 ,305, 262);
UIView *cardViewer = [[UIView alloc] initWithFrame:rect];
UIGraphicsBeginImageContext(cardViewer.bounds.size);
//make view background transparent
cardViewer.backgroundColor = [UIColor colorWithWhite:0.0 alpha:0.0];
cardViewer.opaque = NO;
//stuff items into a subview for capturing
[self.view addSubview:cardViewer];
[cardViewer addSubview:self.tiltedCard];
[cardViewer addSubview:self.bigCardView];
[cardViewer addSubview:self.cardWords];
[cardViewer addSubview:self.photoView];
[cardViewer.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
CGImageRef imageRef = CGImageCreateWithImageInRect([viewImage CGImage], rect);
UIImage *img = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
UIImageWriteToSavedPhotosAlbum(img, nil, nil, nil);
//put everything back where it belongs
[self.view addSubview:self.tiltedCard];
[self.view addSubview:self.bigCardView];
[self.view addSubview:self.cardWords];
[self.view addSubview:self.photoView];
[cardViewer removeFromSuperview];
}
To capture just an area of the screen, specify the bounds using CGRectMake.
CGRect rect = CGRectMake(50, 50, 100, 100);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
[self.view.layer renderInContext:context];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
In the example above we are capturing a 100px by 100px region beginning at x:50px and y:50px.
maybe get the picture of the layer by rendering the layer context and grabbing the image, I use this for displaying fancy animations
UIGraphicsBeginImageContext(self.view.bounds.size);
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
To capture just an area of the screen, use the UIView or SubView and just specify the bounds using CGRectMake.
CGRect rect = CGRectMake(10, 10, 200, 200);
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
[self.YourView.layer renderInContext:context]; // Make sure here you are using the greetingcardView rather than self.view
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
Note: self.view will capture the whole screen so simply render the view wherever.

capture time remove the tool bar

-(IBAction)printDisplay:(id)sender{
CGRect rect = CGRectMake(0.0,44.0,self.view.frame.size.width,self.view.frame.size.height);
NSValue *rectObj = [NSValue valueWithCGRect:rect];
CGRect rectRestored = [rectObj CGRectValue];
UIGraphicsBeginImageContext(CGSizeMake(rectRestored.size.width, rectRestored.size.height-44));
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);
}
This is code for capture the image from the current screen.
Problem is that I don't want to get the UIToolBar for the capture into the screen for that what to do. My application screenshot looks like this :
and after I take a screenshot of the image :
In short I want the remove the UIToolBar when the snap of the image.
Thanx in advance for spend your valuable time.
#samuel
if the image frame is starting from below the Toolbar, you can just set the rect starting from (0,44). If the image frame is starting from beneath the toolbar from (0.0) just set the toolbarObject.hidden = YES; before taking the screenshot through graphicsContext and reset it back to toolbarObject.hidden = NO; afterwards.
Keep your images and extra stuff(what ever contain you want to capture) in different view and use that view for capture.
In your code lets say Second View named as secondView So code will be :
-(IBAction)printDisplay:(id)sender{
CGRect rect = CGRectMake(0.0,44.0,self.secondView.frame.size.width,self.secondView.frame.size.height);
NSValue *rectObj = [NSValue valueWithCGRect:rect];
CGRect rectRestored = [rectObj CGRectValue];
UIGraphicsBeginImageContext(CGSizeMake(rectRestored.size.width, rectRestored.size.height-44));
[self.secondView.layer renderInContext:UIGraphicsGetCurrentContext()];
viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageWriteToSavedPhotosAlbum(viewImage, nil, nil, nil);
}
Modify the code so that the line
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()];
is
[imageView.layer renderInContext:UIGraphicsGetCurrentContext()];

how to get snap shots of touch part on screen by programming?

I am implementing iphone application in which I want to implement below features.
When user touch on iphone screen then user snap shot will generate of touch area of the screen and save to photo library.
I have done googling but dont get successed.
Please help me for this query.
Thanks in advance
If you are looking for sample code to control the camera. Here is a bare bones Camera application that takes picture and saves it to library
Check out this method, pass the view touched to this method, will send u the image & save it to library.
- (UIImage*) giveScreentshotsOfView:(UIView*) view
{
if (view == nil)
return nil;
UIGraphicsBeginImageContext(view.bounds.size);
[view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
+ (UIImage *) captureView:(UIView *)view
{
CGRect screenRect = [[UIScreen mainScreen] bounds];
UIGraphicsBeginImageContext(screenRect.size);
CGContextRef ctx = UIGraphicsGetCurrentContext();
[[UIColor blackColor] set];
CGContextFillRect(ctx, screenRect);
[view.layer renderInContext:ctx];
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
//save the image to photo album
UIImageWriteToSavedPhotosAlbum(newImage, nil, nil , nil);
}

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];