Hi Nalin,

I posted my quary many time, but you never give solution once a time. If you can give me solution then give me advice.

Khushi

Please can you avoid double posting your question, because it causes confusion and delays.

Secondly in future can you please create a new thread rather than taking over an existing thread.

I will deal with your question here:

https://developer.vuforia.com/forum/ios/vuforia-sdk-how-take-screenshots

N

Hi,

Please give me solution?

khushi

Hi,

I got a half black screen on my album, When i take screenShot.

I written  following code below :-

@interface VBOverlayViewController : OverlayViewController {

 UIButton *takePhoto;

}

@property (nonatomic,assign)UIButton *takePhoto;

//For Take a screen Shot

-(UIImage *)glToUIImage;

-(void)TakePhoto;

@implementation VBOverlayViewController

@synthesize takePhoto;

-(void)loadView

{

   takePhoto = [[UIButton alloc]initWithFrame:CGRectMake(0, 14, 70, 70)];

//    takePhoto.backgroundColor = [UIColor colorWithPatternImage:[]];

    [takePhoto setTitle:@"Take Photo" forState:UIControlStateNormal];

    [takePhoto.titleLabel setFont:[UIFont systemFontOfSize:12.0]];

    [takePhoto addTarget:self action:@selector(TakePhoto) forControlEvents:UIControlEventTouchUpInside];

    [self.view addSubview:takePhoto];

}

-(UIImage *)glToUIImage

{

    NSInteger myDataLength = 320 * 480 * 8;//4

    //allocate array and read pixels into it.

    GLubyte *buffer = (GLubyte *)malloc(myDataLength);

    glReadPixels(0, 0, 320, 480, GL_RGBA, GL_UNSIGNED_BYTE, buffer);

    //gl renders "upside down" so swap top bottom into new array.

    //there's gotta be a better way, but this works.

    GLubyte *buffer2 = (GLubyte *)malloc(myDataLength);

    for(int y = 0; y<480; y++)

    {

        for (int x=0; x<320; x++) {

            buffer2[(479 - y) * 320 * 4 + x] = buffer[y * 4 * 320 + x];//4

        }

    }

    //make data provider with data.

    CGDataProviderRef provider = CGDataProviderCreateWithData(NULL, buffer2, myDataLength, NULL);

    //prep the ingredients

    int bitsPerComponent = 8;//8

    int bitPerPixel = 32;//64

    int bytePerRow = 4 * 320;//4

    CGColorSpaceRef colorSpaceRef = CGColorSpaceCreateDeviceRGB();

    CGBitmapInfo bitmapInfo = kCGBitmapByteOrderDefault;

    CGColorRenderingIntent renderingIntent = kCGRenderingIntentDefault;

    //make the cgimage

    CGImageRef imageRef = CGImageCreate(320, 480, bitsPerComponent, bitPerPixel, bytePerRow, colorSpaceRef, bitmapInfo, provider, NULL, NO, renderingIntent);

    NSLog(@"imageRef:-%@",imageRef);

    //then make the uiImage from that

    UIImage *myImage = [UIImage imageWithCGImage:imageRef];

    NSLog(@"myImage:-%@",myImage);

    return myImage;

}

-(void)TakePhoto

{

    UIImage *image = [self glToUIImage];

    NSLog(@"imge:-%@",image);

    UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Get It!" message:@"Go to the Album." delegate:nilcancelButtonTitle:@"OK" otherButtonTitles:nil];

    [alert show];

    UIImageWriteToSavedPhotosAlbum(image, self, nil, nil);

}

What I do, because I m doing all codes.Please guide me.

Thank you

Khushi

Thanks for taking the time to share that Thomas. :-)

One word of caution - it's advisable to not release the image resources until the callback from UIImageWriteToSavedPhotosAlbum - I've seen crashes where image data was released before the file was saved.

reddog wrote:

Tank You MoSR,
I try to make screenshot whit this method but I can't.
Were exactly I must insert the code in Xcode?

:eek:

In my case, i used the code directly in an IBAction, and called it from a button in InterfaceBuilder. It's a bit of a shabby method, since it requires that you overlay a button as UI on top of your EAGLView, but here goes:

-(IBAction)facebookPhoto:(id)sender
{
    UIImage *outputImage = nil;
    
    CGFloat scale = [[UIScreen mainScreen] scale];
    CGRect s = CGRectMake(0, 0, 320.0f * scale, 480.0f * scale);            
    uint8_t *buffer = (uint8_t *) malloc(s.size.width * s.size.height * 4);
    
    glReadPixels(0, 0, s.size.width, s.size.height, GL_RGBA, GL_UNSIGNED_BYTE, buffer);    
    
    CGDataProviderRef ref = CGDataProviderCreateWithData(NULL, buffer, s.size.width * s.size.height * 4, NULL);
    
    CGImageRef iref = CGImageCreate(s.size.width, s.size.height, 8, 32, s.size.width * 4, CGColorSpaceCreateDeviceRGB(), kCGBitmapByteOrderDefault, ref, NULL, true, kCGRenderingIntentDefault);       
    
    size_t width = CGImageGetWidth(iref);    
    size_t height = CGImageGetHeight(iref);    
    size_t length = width * height * 4;            
    uint32_t *pixels = (uint32_t *)malloc(length);
    
    CGContextRef context = CGBitmapContextCreate(pixels, width, height, 8, width * 4,    
                                                 CGImageGetColorSpace(iref), kCGImageAlphaNoneSkipFirst | kCGBitmapByteOrder32Big);           
    
    CGAffineTransform transform = CGAffineTransformIdentity;    
    transform = CGAffineTransformMakeTranslation(0.0f, height);    
    transform = CGAffineTransformScale(transform, 1.0, -1.0);    
    CGContextConcatCTM(context, transform);            
    CGContextDrawImage(context, CGRectMake(0.0f, 0.0f, width, height), iref);         
    CGImageRef outputRef = CGBitmapContextCreateImage(context);
   
    outputImage = [UIImage imageWithCGImage: outputRef]; 
      
    CGDataProviderRelease(ref);   
    CGImageRelease(iref);    
    CGContextRelease(context);    
    CGImageRelease(outputRef);
    free(pixels);
    free(buffer);
     
    UIImageWriteToSavedPhotosAlbum(outputImage, nil, nil, nil);
}

This code will take a snapshot of what's currently on your EAGLView (including both camera and 3D content), and save it as a photo to your iPhone Photo Album.

The code would best live in your EAGLView and be invoked by whatever action you choose to take a photo.

Tank You MoSR,
I try to make screenshot whit this method but I can't.
Were exactly I must insert the code in Xcode?

:eek:

If you search the forum you'll find a number of threads about this topic.

It's really an iOS issue and there's a good solution here:

Saving screenshot of OpenGL ES content to the Photo Album