if (NSClassFromString(@"MPNowPlayingInfoCenter")) {
NSMutableDictionary * dict = [[NSMutableDictionary alloc] init];
[dict setObject:title forKey:MPMediaItemPropertyAlbumTitle];
[dict setObject:artist forKey:MPMediaItemPropertyArtist];

MPMediaItemArtwork * mArt = [[MPMediaItemArtwork alloc] initWithImage:img];
[dict setObject:mArt forKey:MPMediaItemPropertyArtwork];
[MPNowPlayingInfoCenter defaultCenter].nowPlayingInfo = nil;
[[MPNowPlayingInfoCenter defaultCenter] setNowPlayingInfo:dict];
[dict release];
}

NSBundle* bundle = [NSBundle mainBundle];
NSString* path = [bundle bundlePath];
NSURL * fileURL=[NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/akon、be - you - with.mp3", path]];
AudioFileTypeID fileTypeHint = kAudioFileMP3Type;
NSString *fileExtension = [[fileURL path] pathExtension];
if ([fileExtension isEqual:@"mp3"]||[fileExtension isEqual:@"m4a"])
{
AudioFileID fileID = nil;
OSStatus err = noErr;

err = AudioFileOpenURL( (CFURLRef) fileURL, kAudioFileReadPermission, 0, &fileID );
if( err != noErr ) {
NSLog( @"AudioFileOpenURL failed" );
}
UInt32 id3DataSize = 0;
err = AudioFileGetPropertyInfo( fileID, kAudioFilePropertyID3Tag, &id3DataSize, NULL );

if( err != noErr ) {
NSLog( @"AudioFileGetPropertyInfo failed for ID3 tag" );
}
NSDictionary *piDict = nil;
UInt32 piDataSize = sizeof( piDict );
err = AudioFileGetProperty( fileID, kAudioFilePropertyInfoDictionary, &piDataSize, &piDict );
if( err != noErr ) {
[piDict release];
NSLog( @"AudioFileGetProperty failed for property info dictionary" );
}
CFDataRef AlbumPic= nil;
UInt32 picDataSize = sizeof(picDataSize);
err =AudioFileGetProperty( fileID, kAudioFilePropertyAlbumArtwork, &picDataSize, &AlbumPic);
if( err != noErr ) {
NSLog( @"Get picture failed" );
}
NSData* imagedata= (NSData*)AlbumPic;
UIImage* image=[[UIImage alloc]initWithData:imagedata];
imageView.image=image;
NSString * Album = [(NSDictionary*)piDict objectForKey:
[NSString stringWithUTF8String: kAFInfoDictionary_Album]];
NSString * Artist = [(NSDictionary*)piDict objectForKey:
[NSString stringWithUTF8String: kAFInfoDictionary_Artist]];
NSString * Title = [(NSDictionary*)piDict objectForKey:
[NSString stringWithUTF8String: kAFInfoDictionary_Title]];
NSLog(@"%@",Title);

NSLog(@"%@",Artist);

NSLog(@"%@",Album);

}

AVURLAsset *avURLAsset = [AVURLAsset URLAssetWithURL:url
options:nil];
for (NSString *format in [avURLAsset availableMetadataFormats]) {
//NSLog(@"-------format:%@",format);
for (AVMetadataItem *metadataItem in [avURLAsset metadataForFormat:format]) {
//NSLog(@"commonKey:%@",metadataItem.commonKey);
if ([metadataItem.commonKey isEqualToString:@"artwork"]) {
//取出封面artwork，从data转成image显示
MPMediaItemArtwork *mArt = [[MPMediaItemArtwork alloc] initWithImage:[UIImage imageWithData:[(NSDictionary*)metadataItem.value objectForKey:@"data"]]];
[dict setObject:mArt
forKey:MPMediaItemPropertyArtwork];
break;
}
}
}