Check from URL is a image URL or not by checking file's extension. You can check another file type: music or video ...

image-url-validation.m

- (BOOL)isImageURLValid:(NSURL *)imageURL
{
    NSArray *imageExtensions = @[@"jpg", @"jpeg", @"png", @"gif", @"tiff"]; // Add more if you want
    NSString *extension = [imageURL pathExtension];
    
    for (NSString *ext in imageExtensions) {
        if ([ext isEqualToString:extension]) {
            return YES;
        }
    }
    
    return NO;
}