Get List of all Video and Thumbnails
With the help of above answer I got it working..
Thanks to @Nikhil Bansal,
it helped me, but still it required couple of hours to make the code executable as he is missing few things in his answer

So I would like to share my full working code
1.just add frameworks AssetsLibrary, AVFoundation and MediaPlayer.
2.AssetBrowserItem.h and AssetBrowserItem.m here
3.use below code to get list of all videos from ios device lib
4.run app and see Log for videos details
#import "HomeViewController.h"
#import <AssetsLibrary/AssetsLibrary.h>
#import <MediaPlayer/MediaPlayer.h>
#import <AVFoundation/AVFoundation.h>
#import "AssetBrowserItem.h"
@interface HomeViewController ()
@property (nonatomic, strong) ALAssetsLibrary *assetsLibrary;
@property (nonatomic, strong) NSURL *videoURL;
@property (nonatomic, strong) MPMoviePlayerController *mpVideoPlayer;
@property (nonatomic, strong) NSMutableArray *videoURLArray;
@property (nonatomic, strong) NSMutableArray *assetItems;
@property (nonatomic, strong) NSMutableDictionary *dic;
@end
@implementation HomeViewController
@synthesize assetsLibrary, assetItems,dic;
@synthesize videoURL,videoURLArray, mpVideoPlayer;
- (void)viewDidLoad
{
[super viewDidLoad];
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
}
#pragma mark - Show Video List Methods
- (IBAction)showVideoList:(id)sender
{
[self buildAssetsLibrary];
}
- (void)buildAssetsLibrary
{
assetsLibrary = [[ALAssetsLibrary alloc] init];
ALAssetsLibrary *notificationSender = nil;
videoURLArray = [[NSMutableArray alloc] init];
NSString *minimumSystemVersion = @"4.1";
NSString *systemVersion = [[UIDevice currentDevice] systemVersion];
if ([systemVersion compare:minimumSystemVersion options:NSNumericSearch] != NSOrderedAscending)
notificationSender = assetsLibrary;
[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(assetsLibraryDidChange:) name:ALAssetsLibraryChangedNotification object:notificationSender];
[self updateAssetsLibrary];
}
- (void)assetsLibraryDidChange:(NSNotification*)changeNotification
{
[self updateAssetsLibrary];
}
- (void)updateAssetsLibrary
{
assetItems = [NSMutableArray arrayWithCapacity:0];
ALAssetsLibrary *assetLibrary = assetsLibrary;
[assetLibrary enumerateGroupsWithTypes:ALAssetsGroupAll usingBlock:^(ALAssetsGroup *group, BOOL *stop)
{
if (group)
{
[group setAssetsFilter:[ALAssetsFilter allVideos]];
[group enumerateAssetsUsingBlock:^(ALAsset *asset, NSUInteger index, BOOL *stop)
{
if (asset)
{
dic = [[NSMutableDictionary alloc] init];
ALAssetRepresentation *defaultRepresentation = [asset defaultRepresentation];
NSString *uti = [defaultRepresentation UTI];
videoURL = [[asset valueForProperty:ALAssetPropertyURLs] valueForKey:uti];
mpVideoPlayer = [[MPMoviePlayerController alloc] initWithContentURL:videoURL];
NSString *title = [NSString stringWithFormat:@"%@ %lu", NSLocalizedString(@"Video", nil), [assetItems count]+1];
[self performSelector:@selector(imageFromVideoURL)];
[dic setValue:title forKey:@"VideoTitle"];//kName
[dic setValue:videoURL forKey:@"VideoUrl"];//kURL
AssetBrowserItem *item = [[AssetBrowserItem alloc] initWithURL:videoURL title:title];
[assetItems addObject:item];
[videoURLArray addObject:dic];
NSLog(@"Video has info:%@",videoURLArray);
}
NSLog(@"Values of dictonary==>%@", dic);
//NSLog(@"assetItems:%@",assetItems);
NSLog(@"Videos Are:%@",videoURLArray);
} ];
}
// group == nil signals we are done iterating.
else
{
dispatch_async(dispatch_get_main_queue(), ^{
//[self updateBrowserItemsAndSignalDelegate:assetItems];
// loadImgView.hidden = NO;
// [spinner stopAnimating];
// [loadImgView removeFromSuperview];
//selectVideoBtn .userInteractionEnabled = YES;
});
}
}
failureBlock:^(NSError *error)
{
NSLog(@"error enumerating AssetLibrary groups %@\n", error);
}];
}
- (UIImage *)imageFromVideoURL
{
UIImage *image = nil;
AVAsset *asset = [[AVURLAsset alloc] initWithURL:videoURL options:nil];;
AVAssetImageGenerator *imageGenerator = [[AVAssetImageGenerator alloc] initWithAsset:asset];
imageGenerator.appliesPreferredTrackTransform = YES;
// calc midpoint time of video
Float64 durationSeconds = CMTimeGetSeconds([asset duration]);
CMTime midpoint = CMTimeMakeWithSeconds(durationSeconds/2.0, 600);
// get the image from
NSError *error = nil;
CMTime actualTime;
CGImageRef halfWayImage = [imageGenerator copyCGImageAtTime:midpoint actualTime:&actualTime error:&error];
if (halfWayImage != NULL)
{
// cgimage to uiimage
image = [[UIImage alloc] initWithCGImage:halfWayImage];
[dic setValue:image forKey:@"ImageThumbnail"];//kImage
NSLog(@"Values of dictonary==>%@", dic);
NSLog(@"Videos Are:%@",videoURLArray);
CGImageRelease(halfWayImage);
}
return image;
}
@end