Reputation: 917
I need to merge two images into one image, here is my code:
-(UIImage*)mergeImage:(UIImage*)mask overImage:(UIImage*)source inSize:(CGSize)size
{
//Capture image context ref
UIImageView *totalimage=[[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 200, 200)];
UIImageView *firstImage=[[UIImageView alloc] initWithImage:mask];
UIImageView *secondImage=[[UIImageView alloc] initWithImage:source];
[totalimage addSubview:firstImage];
[totalimage addSubview:secondImage];
UIGraphicsBeginImageContext(totalimage.bounds.size);
[totalimage.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
//Draw images onto the context
[source drawInRect:CGRectMake(0, 0, source.size.width, source.size.height)];
[mask drawInRect:CGRectMake(0, 0, mask.size.width, mask.size.height)];
return viewImage;
}
I call this method as follows:
UIImage *totalImage = [self mergeImage:self.Apicimage overImage:questionImage inSize:CGSizeMake(100, 100)];
but on execution I get this output:
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextSaveGState: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextSetBlendMode: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextSetAlpha: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextTranslateCTM: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextScaleCTM: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextConcatCTM: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextDrawImage: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextRestoreGState: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextSaveGState: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextSetBlendMode: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextSetAlpha: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextTranslateCTM: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextScaleCTM: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextConcatCTM: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextDrawImage: invalid context 0x0
Jun 15 16:11:06 iPad-2 VueGuides[9195] <Error>: CGContextRestoreGState: invalid context 0x0
can anyone guide me please. How can I merge two images?
Upvotes: 2
Views: 2819
Reputation: 2683
your code
[source drawInRect:CGRectMake(0, 0, source.size.width, source.size.height)];
[mask drawInRect:CGRectMake(0, 0, mask.size.width, mask.size.height)];
should be written before
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
Upvotes: 3