Question

I am using Core Image and GPUImage to make some filters in an iPhone app. I seem to be running out of memory and crashing with larger images. I think this can be solved if I can split the input image into multiple parts.

How to efficiently split an image in multiple parts for image processing, then recombine to output the resulting image as a whole in iOS?

Answer 1

-(void)getMultipleImages:(UIImage*)image AndNumberOfPart:(NSInteger)matrixSize{



CGSize size = image.size;

//for storing rect values of puzzle boxess
NSMutableArray *puzzleRectArr = [[NSMutableArray alloc]init];
NSMutableArray *puzzleCroppedObj = [[NSMutableArray alloc]init];

int widthD = size.width;
int heightD = size.height;

float boxWidth = widthD/matrixSize;
float boxHeight = heightD/matrixSize;


for (int i = 0; i < matrixSize*matrixSize; i++) {

    int x = (widthD/matrixSize)/2 + (widthD/matrixSize) *(i%matrixSize)-boxWidth/2;
    int y = (heightD/matrixSize)/2 + (heightD/matrixSize)* (i/matrixSize)-boxHeight/2;


    CGRect rect = CGRectMake(x, y, boxWidth, boxHeight);
    [puzzleRectArr addObject:[NSValue valueWithCGRect:rect]];

    CGImageRef imageRef = CGImageCreateWithImageInRect([self.imgActual CGImage], rect);
    UIImage *croppedImage = [UIImage imageWithCGImage:imageRef];
//----------------------------------------------------------------------        
    //here You can find the part image
    [puzzleCroppedObj addObject:croppedImage];

//----------------------------------------------------------------------                


     CGImageRelease(imageRef);
}
}