I created a function for splitting an image into multiple images, but when I take take the CGImage of the UIImage, the CGImage returns NULL
NSArray* splitIma
Convert CGImage to UIImage with this and cgImage will not be null:
func convert(cmage:CIImage) -> UIImage
{
let context:CIContext = CIContext.init(options: nil)
let cgImage:CGImage = context.createCGImage(cmage, from: cmage.extent)!
let image:UIImage = UIImage.init(cgImage: cgImage)
return image
}
The CGImage property will return nil if the UIImage was created from another image such as an IOSurface or CIImage. To get around this in this particular case I can create a CGImage from an IOSurface using the c function then convert that to a UIImage.
UICreateCGImageFromIOSurface(IOSurfaceRef surface);
It happens in some cases when we try to crop image. I found the solution like this try this may be this can help you:-
NSData *imageData = UIImageJPEGRepresentation(yourImage, 0.9);
newImage = [UIImage imageWithData:imageData];
I have created UIImage
from CGImage
.
CIImage *ciImage = image.CIImage;
CIContext *context = [CIContext contextWithOptions:nil];
CGImageRef ref = [context createCGImage:ciImage fromRect:ciImage.extent];
UIImage *newImage = [UIImage imageWithCGImage:ref];
And now newImage.CGImage
is not nil
What you did now is just create pieces with 0.f width, you should use two for
s to define the width
& height
for your pieces. Code sample like this (not tested yet, but it should works):
for (int height = 0; height < image.size.height; height += piecesSize) {
for (int width = 0; width < image.size.width; width += piecesSize) {
CGRect subFrame = CGRectMake(width, height, piecesSize, piecesSize);
CGImageRef newImage = CGImageCreateWithImageInRect(image.CGImage, subFrame);
UIImage * finalImage = [UIImage imageWithCGImage:newImage];
CGImageRelease(newImage);
[tempArray addObject:finalImage];
}
}