how to compare image array to find duplicate image in ios

Question

i am working on one app called duplicate image finder for IOS. my question is how to compare image array to find duplicate. suppose i have array of images and i want to find duplicate images from this array. how can i find it? any suggestions. i have used method that is convert image to data and compare data of image with each other that works perfectly in simulator but not working properly in device.

for (int i=0; i<arrImageData1.count; i++)
    {
        for (int j=i+1; j<arrImageData1.count; j++)
        {
            if ([[arrImageData1 objectAtIndex:i] length]==[[arrImageData2 objectAtIndex:j]length])
            {
                NSNumber *iValue = [NSNumber numberWithInt:i];
                NSNumber *jValue = [NSNumber numberWithInt:j];
                [arr addObject:iValue];
                [arr addObject:jValue];
            }
        }
    }
    NSLog(@"%@",arr);
    NSLog(@"%lu",(unsigned long)arr.count);
    for (int k=0; k<arr.count; k++)
    {
        [arrDuplicateImages addObject:[arrImage objectAtIndex:[[arr objectAtIndex:k] integerValue]]];
    }
}

i tried this but not working in real device – Harshit Dec 22 '15 at 06:58 — Harshit, Dec 22 '15 at 06:58

Shubham bairagi · Answer 1 · 2015-12-22T08:20:45.923

2

I preferred in my project comparing image Data. And it worked fine if you want to try :

UIImage *image = [UIImage imageNamed:@"image1.jpeg"];
NSData *imageData= UIImageJPEGRepresentation(image,0.0);
UIImage *imageDuplicate = [UIImage imageNamed:@"image1 copy.jpeg"];
NSData *imageDuplicateData= UIImageJPEGRepresentation(imageDuplicate,0.0);

now you need to get string from your imageData:

NSString *str1 = [NSString stringWithFormat:@"%@",imageData];
NSString *str2 = [NSString stringWithFormat:@"%@",imageDuplicateData];

if ([str1 isEqualToString:str2]){
    NSLog(@"same images");
} else {
    NSLog(@"images are different");

}

edited Dec 22 '15 at 08:20

answered Dec 22 '15 at 08:15

Shubham bairagi

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but i am working with native photo app...i fetch all images from photo app and find duplicate from it... – Harshit Dec 22 '15 at 09:43
are you using Any type of paging for getting images array ? – Shubham bairagi Dec 22 '15 at 09:47
yup......................... – Harshit Dec 22 '15 at 09:59
then i can suggest one way use NSSet. when you will get array of images add it to NSSet. this set contain strings whatever we obtained from image Data. – Shubham bairagi Dec 22 '15 at 10:03
let me try this...... – Harshit Dec 22 '15 at 11:35

how to compare image array to find duplicate image in ios

1 Answers1