Objective-c – iOS AVFoundation: How to get artwork from the MP3 file?

- (void)metadata {
AVURLAsset *asset = [AVURLAsset URLAssetWithURL: self.fileURL options:nil];

NSArray *artworks = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata withKey:AVMetadataCommonKeyArtwork keySpace:AVMetadataKeySpaceCommon];
NSArray *titles = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata withKey:AVMetadataCommonKeyTitle keySpace:AVMetadataKeySpaceCommon];
NSArray *artists = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata withKey:AVMetadataCommonKeyArtist keySpace:AVMetadataKeySpaceCommon];
NSArray keySpaceCommon];
NSArray keyCommonKeySpaceCommon];
NSArray keyCommonKeySpaceCommon]; :AVMetadataKeySpaceCommon];

AVMetadataItem *artwork = [artworks objectAtIndex:0];
AVMetadataItem *title = [titles objectAtIndex:0];
AVMetadataItem *artist = [artists objectAtIndex: 0];
AVMetadataItem *albumName = [album Names objectAtIndex:0];

if ([artwork.keySpace isEqualToString:AVMetadataKeySpaceID3]) {
 NSDictionary *dictionary = [artwork.value copyWithZone:nil];
 self.currentSongArtwork = [UIImage imageWithData:[dictionary objectForKey:@"data"]];
}
else if ([artwork.keySpace isEqualToString:AVMetadataKeySpaceiTunes]) {
 self.currentSongArtwork = [UIImage imageWithData: [artwork.value copyWithZone:nil]];
}

self.currentSongTitle = [title.value copyWithZone:nil];
self.currentSongArtist = [artist.value copyWithZone: nil];
self.currentSongAlbumName = [albumName.value copyWithZone:nil];
self.currentSongDuration = self.audioPlayer.duration;
}

- (void)metadata {
AVURLAsset *asset = [AVURLAsset URLAssetWithURL:self.fileURL options:nil];

NSArray *titles = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata withKey:AVMetadataCommonKeyTitle keySpace:AVMetadataKeySpaceCommon];
NSArray *artists = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata withKey:AVMetadataCommonKeySpace withKey:AVMetadataCommonKeySpace:CommonKeySpace />AVMetadata
 = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata withKey:AVMetadataCommonKeyAlbumName keySpace:AVMetadataKeySpaceCommon];

AVMetadataItem *title = [titles objectAtIndex:0];
AVMetadataItem *artist = [artists objectAtIndex:0]; 
AVMetadataItem *albumName = [albumNames objectAtIndex:0];


NSArray *keys = [NSArray arrayWithObjects:@"commonMetadata", nil];
[asset loadValuesAsynchronouslyForKey s:keys completionHandler:^{
 NSArray *artworks = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata
 withKey:AVMetadataCommonKeyArtwork
 keySpace:AVMetadataKeySpaceCommon];

 for (AVMetadataItem * item in artworks) {
 if ([item.keySpace isEqualToString:AVMetadataKeySpaceID3]) {
 NSDictionary *d = [item.value copyWithZone:nil];
 self.currentSongArtwork = [UIImage imageWithData: [d objectForKey:@"data"]];
} else if ([item.keySpace isEqualToString:AVMetadataKeySpaceiTunes]) {
 self.currentSongArtwork = [UIImage imageWithData:[item.value copyWithZone:nil]] ;
 }
 }
}];


self.currentSongTitle = [title.value copyWithZone:nil];
self.currentSongArtist = [artist.value copyWithZone:nil];
self.currentSongAlbumName = [albumName.value c opyWithZone:nil];
self.currentSongDuration = self.audioPlayer.duration;
}

My code:

- (void)metadata {
AVURLAsset *asset = [AVURLAsset URLAssetWithURL:self.fileURL options:nil];

NSArray *artworks = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata withKey:AVMetadataCommonKeyArtwork keySpace:AVMetadataKeySpaceCommon];
NSArray *titles = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata withKey:AVMetadataCommonKeyTitle:KeySpace:AVMetadataCommonKeyTitle: keySpace:AVMetadataCommonKeyTitle:KeySpace:AVMetadataCommonKeyArrayFrom];
 commonMetadata withKey:AVMetadataCommonKeyArtist keySpace:AVMetadataKeySpaceCommon];
NSArray *albumNames = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata withKey:AVMetadataCommonKeyAlbumName keySpace:AVMetadataKeySpaceCommon];

ArtIndex: 0 ;
AVMetadataItem *title = [titles objectAtIndex:0];
AVMetadataItem *ar tist = [artists objectAtIndex:0];
AVMetadataItem *albumName = [albumNames objectAtIndex:0];

if ([artwork.keySpace isEqualToString:AVMetadataKeySpaceID3]) {
 NSDictionary * dictionary = [artwork.value copyWithZone:nil];
 self.currentSongArtwork = [UIImage imageWithData:[dictionary objectForKey:@"data"]];
}
else if ([artwork.keySpace isEqualToString:AVMetadataKeySpaceiTunes]) {
 self.currentSongArtwork = [UIImage imageWithData:[artwork.value copyWithZone:nil]];
}

self.currentSongTitle = [title.value copyWithZone :nil];
self.currentSongArtist = [artist.value copyWithZone:nil];
self.currentSongAlbumName = [albumName.value copyWithZone:nil];
self.currentSongDuration = self.audioPlayer. duration;
}

This works for getting artwork from m4a files, but not for mp3 files. If the asset points to an mp3 file, the artwork is empty. What am I doing wrong, How can I solve it?

I found that when setting the image synchronously, the artwork is loaded asynchronously. I solved it like this:

- (void)metadata {
AVURLAsset *asset = [AVURLAsset URLAssetWithURL:self.fileURL options:nil];

NSArray *titles = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata withKey:AVMetadataCommonKeyTitle keySpace:AVMetadataKeySpaceCommon];
NSArray *artists = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata withKey:AVMetadataCommonKeyArtist keySpace:AVMetadataKeySpaceCommon];
NSArray keySpaceCommon];
NSArray keyCommonKeySpaceCommon];
NSArray keyCommonKeySpaceCommon]; :AVMetadataKeySpaceCommon];

AVMetadataItem *title = [titles objectAtIndex:0];
AVMetadataItem *artist = [artists objectAtIndex:0];
AVMetadataItem *albumName = [albumNames objectAtIndex: 0];


NSArray *keys = [NSArray arrayWithObjects:@"commonMetadata", nil];
[asset loadValuesAsynchronouslyForKeys:keys completionHandler:^{
 NSArray * artwork s = [AVMetadataItem metadataItemsFromArray:asset.commonMetadata
 withKey:AVMetadataCommonKeyArtwork
 keySpace:AVMetadataKeySpaceCommon];

 for (AVMetadataItem *item in artworks) {
 if ([item .keySpace isEqualToString:AVMetadataKeySpaceID3]) {
 NSDictionary *d = [item.value copyWithZone:nil];
 self.currentSongArtwork = [UIImage imageWithData:[d objectForKey:@"data"]];
} else if ([item.keySpace isEqualToString:AVMetadataKeySpaceiTunes]) {
 self.currentSongArtwork = [UIImage imageWithData:[item.value copyWithZone:nil]];
 }
 }
}];


self.currentSongTitle = [title.value copyWithZone:nil];
self.currentSongArtist = [artist.value copyWithZone:nil];
self.currentSongAlbumName = [albumName.value copyWithZone:nil];
self.currentSongDuration = sel f.audioPlayer.duration;
}