How to take clear screenShot IOS

Question

I am working on IOS Application in which taking clear screen shot is required I've tried

func captureView() -> UIImage {
        //hide controls if needed
        let rect: CGRect = self.imageView.frame
        UIGraphicsBeginImageContext(rect.size)
        let context: CGContextRef = UIGraphicsGetCurrentContext()!
        self.view.layer.renderInContext(context)
        let img: UIImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return img
    }

But the quality of image is not good. Please suggest me something for it.

Answer 1

change the line

UIGraphicsBeginImageContext(rect.size)

to

UIGraphicsBeginImageContextWithOptions(rect.size, false, 0.0);

Answer 2

Add the below code block in a new file. And, there you go.

extension UIView {

    // Convert a uiview to uiimage
        func captureView() -> UIImage {
            // Gradually increase the number for high resolution.     
            let scale = 1.0 

            UIGraphicsBeginImageContextWithOptions(bounds.size, opaque, scale)   

            layer.renderInContext(UIGraphicsGetCurrentContext()!)
            let image:UIImage  = UIGraphicsGetImageFromCurrentImageContext()
            UIGraphicsEndImageContext()

            return image
        }
    }

Now, you can call captureView() on any subclass of UIView and UIView itself to get the UIImage of the view.

You can change the value of scale in UIGraphicsBeginImageContextWithOptions method to get a high resolution image.

Answer 3

You can use the IOSurface private framework to do so

IOMobileFramebufferConnection connect;
kern_return_t result;
IOSurfaceRef screenSurface = NULL;

io_service_t framebufferService = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching("AppleH1CLCD"));
if(!framebufferService)
    framebufferService = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching("AppleM2CLCD"));
if(!framebufferService)
    framebufferService = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching("AppleCLCD"));

result = IOMobileFramebufferOpen(framebufferService, mach_task_self(), 0, &connect);

result = IOMobileFramebufferGetLayerDefaultSurface(connect, 0, &screenSurface);

uint32_t aseed;
IOSurfaceLock(screenSurface, kIOSurfaceLockReadOnly, &aseed);
uint32_t width = IOSurfaceGetWidth(screenSurface);
uint32_t height = IOSurfaceGetHeight(screenSurface);

CFMutableDictionaryRef dict;
int pitch = width*4, size = width*height*4;
int bPE=4;
char pixelFormat[4] = {'A','R','G','B'};
dict = CFDictionaryCreateMutable(kCFAllocatorDefault, 0, &kCFTypeDictionaryKeyCallBacks, &kCFTypeDictionaryValueCallBacks);
CFDictionarySetValue(dict, kIOSurfaceIsGlobal, kCFBooleanTrue);
CFDictionarySetValue(dict, kIOSurfaceBytesPerRow, CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &pitch));
CFDictionarySetValue(dict, kIOSurfaceBytesPerElement, CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &bPE));
CFDictionarySetValue(dict, kIOSurfaceWidth, CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &width));
CFDictionarySetValue(dict, kIOSurfaceHeight, CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &height));
CFDictionarySetValue(dict, kIOSurfacePixelFormat, CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, pixelFormat));
CFDictionarySetValue(dict, kIOSurfaceAllocSize, CFNumberCreate(kCFAllocatorDefault, kCFNumberSInt32Type, &size));

IOSurfaceRef destSurf = IOSurfaceCreate(dict);

void* outAcc;
IOSurfaceAcceleratorCreate(NULL, 0, &outAcc);

IOSurfaceAcceleratorTransferSurface(outAcc, screenSurface, destSurf, dict, NULL);

IOSurfaceUnlock(screenSurface, kIOSurfaceLockReadOnly, &aseed);
CFRelease(outAcc);

CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, IOSurfaceGetBaseAddress(destSurf), (width * height * 4), NULL);
CGImageRef cgImage=CGImageCreate(width, height, 8,
                                 8*4, IOSurfaceGetBytesPerRow(destSurf),
                                 CGColorSpaceCreateDeviceRGB(), kCGImageAlphaNoneSkipFirst |kCGBitmapByteOrder32Little,
                                 provider, NULL,
                                 YES, kCGRenderingIntentDefault);
UIImage *img = [UIImage imageWithCGImage:cgImage];