I'd like to use an MPMediaPickerController to allow a user to select a song from his/her iPod library. From there he/she should be able to select a clip (~15s) of the song by specifying a start time and end time. Finally, the user should be able to send that clip to a friend or post it to a social network. For this, I think I'll need to create a new audio file from the raw iPod audio data.
My approach so far is to select the song, then get an AssetURL in the callback like so:
- (void) mediaPicker: (MPMediaPickerController *) mediaPicker
didPickMediaItems: (MPMediaItemCollection *) collection {
MPMediaItem *item = [[collection items] objectAtIndex:0];
NSURL *url = [item valueForProperty:MPMediaItemPropertyAssetURL];
}
Then I can process the audio using (pseudocode):
ExtAudioFileCreateWithURL:url
The problem is that some songs have a null URL. Is this do to some sort of DRM restriction, and if so is there a workaround? Is this the best approach for the desired task?
Turned out it was a DRM restriction.
Related
I'm trying to establish a simple audio stream to a Chromecast device. This is just a POC for me to familiarize myself with the API. What I want to do is load up the user's library, select a song, and have it cast over. I've been following the integration guide quite closely but to no avail.
Please find the full project on Github here.
An overview of my code, AppDelegate.m:
- (BOOL)application:(UIApplication*)application didFinishLaunchingWithOptions:(NSDictionary*)launchOptions
{
GCKCastOptions *options = [GCKCastOptions.alloc initWithReceiverApplicationID:kGCKMediaDefaultReceiverApplicationID];
[GCKCastContext setSharedInstanceWithOptions:options];
[GCKCastContext.sharedInstance.sessionManager addListener:self];
}
UITableViewDelegate:
- (void)tableView:(UITableView*)tableView didSelectRowAtIndexPath:(NSIndexPath*)indexPath
{
MPMediaItem *mediaItem = MusicManager.sharedManager[index];
NSString *path = [MPMediaLibrary.defaultMediaLibrary pathForAssetURL:mediaItem.assetURL];
GCKMediaMetadata *metadata = [GCKMediaMetadata.alloc initWithMetadataType:GCKMediaMetadataTypeMusicTrack];
[metadata setString:mediaItem.title forKey:kGCKMetadataKeyTitle];
[metadata setString:mediaItem.artist forKey:kGCKMetadataKeyArtist];
[metadata setString:mediaItem.albumTitle forKey:kGCKMetadataKeyAlbumTitle];
GCKMediaInformation *mediaInfo = [GCKMediaInformation.alloc initWithContentID:path
streamType:GCKMediaStreamTypeBuffered
contentType:[self fileMIMEType:path]
metadata:metadata
streamDuration:mediaItem.playbackDuration
customData:nil];
[GCKCastContext.sharedInstance.sessionManager.currentCastSession.remoteMediaClient loadMedia:mediaInfo autoplay:YES];
}
I initiate the casting session by tapping the GCKCastButton and Start Session, my TV shows the Cast logo, then when I tap on a specific song, my TV briefly shows the metadata (i.e. song title, artist name, etc.), and then reverts back to the Chromecast logo. On the device, if I remain on the screen presented by GCKCastButton, I can also see the details of the song that is supposed to be currently casting, but quickly changes to "No Media Selected" after a few seconds.
I've checked the file path, the MIME type, everything is correct and playable. I've even tried bundling a short MP3 and trying to cast that, but to no avail.
Can't help but feel like I'm missing something here, the integration guide doesn't really give much more info.
Any insight is appreciated. Thanks!
It seems that I was under the wrong impression that the cast library initiates a stream from the provided file itself. But instead it required an actual URL for the Chromecast device to perform a GET operation on.
I imagine this will be solved by running a server locally on the iOS device.
I am working on a project where I need to play songs from iTunes Library in AVPlayer. For that, I am taking URL "ipod-library://item/item.mp3?id=1577682869916034242" of selected songs from iTunes Library and playing same in AVPlayer. Almost all songs get play, but for few songs MPMediaItemPropertyAssetURL returns nil URL. Also receive following error
-[AVAssetReader initWithAsset:error:] invalid parameter not satisfying: asset != ((void *)0)
Any suggestion on this? and why I am getting nil value from
MPMediaItemPropertyAssetURL
Also any idea how to stream or convert DRM Protected Media track into NSData?.
Please advice.
MPMediaItemPropertyAssetURL can returns null for two possible reason.
The music is not downloaded to your device but added in music
library only.
The music is loaded but its DRM-protected.
DRM-protected asset is not possible to play using AVPlayer, its only able to play using MPMusicPlayer. So you must need to check two things before proceed with AVPlayer.
MPMediaItemPropertyAssetURL is nil ?
MPMediaItem is protected ?
Please see the code below….
MPMediaItem *theChosenSong = [[mediaItemCollection items] firstObject];
NSURL *assetURL = [theChosenSong valueForProperty:MPMediaItemPropertyAssetURL];
if(assetURL) {
BOOL bIsProtected = theChosenSong.protectedAsset;
if(!bIsProtected) {
// Do whatever you want to do
NSLog(#"Its not protected");
}
else {
NSLog(#"Its DRM protected");
}
}
else {
NSLog(#"DRM protected or not downloaded locally");
}
I found out that the problem was the song I was trying to get the MPMediaItemPropertyAssetURL property for was actually not on my device. It was listed in the media library, but was actually still in iCloud. Once I downloaded the song to my device then the problem was solved.
Leaving this answer for other people like me.
Even though the music is on downloaded on the device, if it is DRM protected, MPMediaItem.value(forProperty: MPMediaItemPropertyAssetURL) will return nil as mentioned in the comment.
My app kept crashing and I confirmed this with my beta tester.
It seems like MPMusicPlayerController still supports playback so according to this answer.
I need to play n tracks one after another with ability to switch to next/previous song and pause. Songs are located in Documents folder.
I looked in AVQueuePlayer, but it seems that this approach is not working with local files, playing by url works fine. Now i can play one song with AVAudioPlayer like this:
NSURL *url = [NSURL fileURLWithPath:[node path]];
self.player = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:nil];
[self.player play];
But it seems that playing bunch of tracks one after another this way is not the best practice.
May be there are frameworks that implement this in more convenient way?
Any suggestions?
StreamingKit is probably what your looking for.
I have been using the following code to extract the asset url from the MPMediaItem object returned from the MPMediaItemPickerController so that I can copy music files from a users iPhone itunes music library to the documents folder for processing, but on iPhone 5s I always get a null value from the MPMediaItemPropertyAssetURL, but when I run the same code on iPhone 4 or iPhone 5 it works as it should returning a proper url.
- (void) mediaPicker: (MPMediaPickerController *) mediaPicker didPickMediaItems: (MPMediaItemCollection *) mediaItemCollection {
[self dismissViewControllerAnimated:YES completion:nil];
if(mediaItemCollection){
MPMediaItem *mediaItem = (MPMediaItem *)[mediaItemCollection.items objectAtIndex: 0];
NSString *songTitle = [mediaItem valueForProperty: MPMediaItemPropertyTitle];
NSLog(#"songtitle: %#", songTitle);
NSURL *assetURL = [mediaItem valueForProperty: MPMediaItemPropertyAssetURL];
NSLog(#"%#", assetURL);
}
}
I have tried removing arm64 from valid architectures and only building for armv7 and armv7s, but that didn't fix this problem.
Does anyone know why this is happening and how I can fix it or if there is a workaround I can use? I need to be able to copy music from the iPhone's music library to the documents folder so that I can process the music properly for a dj application.
Thanks
I found out that the problem was the song I was trying to get the MPMediaItemPropertyAssetURL property for was actually not on my device. It was listed in the media library, but was actually still in iCloud. Once I downloaded the song to my device then the problem was solved. As much as I don't like answering my own question I took Jeroen's advice so that it can hopefully help others.
We can add filter that does not show iCloud items with
[mediaPicker setShowsCloudItems:NO];
I am working on an interactive children's book for the iPad that has a "read to me" option.
For each page (that has an index), theres an audio clip that produces the "read to me" feature. The feature works well, except for the fact that when I turn the page, the previous pages audio still plays, even when the new audio starts, here's my example:
- (void) didTurnToPageAtIndex:(NSUInteger)index
{
if ([delegate respondsToSelector:#selector(leavesView:didTurnToPageAtIndex:)])
[delegate leavesView:self didTurnToPageAtIndex:index];
if([[NSUserDefaults standardUserDefaults] boolForKey:#"kReadToMe"] == YES)
{
NSString* filename = [voices objectAtIndex:index];
NSString *path = [[NSBundle mainBundle] pathForResource:filename ofType:#"m4v"];
NSLog(#"File: %#, Index: %i",path,index);
//Create new audio for next page
AVAudioPlayer * newAudio = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] error:nil];
rtmAudio = newAudio; // automatically retain audio and dealloc old file if new file is loaded
//[newAudio release];
[rtmAudio play];
}
}
Say for instance, I turn to page 3 before the audio for page 2 stops playing, both clips play over eachother, which will annoy the sh*t out of kids, I know it does me.
I've tried placing [rtmAudio stop] before I allocate the new file, but that doesnt seem to work. I need a way to kill the prevous audio clip before starting the new clip.
I would suggest that you have one instance of the audio player in your whole application. Then you can check if it playing, if so stop it and then move on.
you are creating a new player in this method before stopping the old.... I believe
As AlexChaffee mentioned the Apple docs, "Play multiple sounds simultaneously, one sound per audio player, with precise synchronization". It seems preferable to use multipe instances across the app with NSNotificationCenter's notifications.