Accessing Metadata from currently playing audio. (Builtin or External App) - android

I am trying to develop an app/widget for which I need display the currently playing information (metadata) of an audio track.
This would be trivial if I was also writing the MediaPlayer myself, as I could simply access the MediaStore and bring up the info, however, I do not wish to compete with the plethora of existing apps on this front. I want to be able to pull this inforrmation from the builtin audio player or other app such as SongBird or PowerAMP.
I should be able to do this with PowerAMP using their [API][1], but have, but I really want a solution that works for the stock android player and others too.
I was hoping to be able to grab the information from the AudioManager, but that seems only to allow me to query the current state (Music is playing et) and I can set my intent to play music, etc... But no access to metadata from someone elses app.
So my thought is this cannot be done easily. My thoughts are that I could maybe access this info from the info bar at the top as the now playing info is printed up there. It might be an ugly hack though...
For a moment I got excited about the RemoteControlClient.MetadataEditor from 4.0, but then I figured out that it was for writing that information to a stream that can be sent to the physical remote, rather than allowing you to create a software remote. Damn!
Does anyone have any ideas?
[1]: http://forum.powerampapp.com/index.php?/topic/1034-updated-for-20-poweramp-api-lib-and-sample-applications/ Power AMP

I've written a guide for implementing this.
Basically, you need to have access to hidden classes of android.jar library. Then you have to extend IRemoteControlDisplay$Stub class, and implement it's methods.
After that you register your RemoteControlDisplay with hidden method - AudioManager#registerRemoteControlDisplay.
There is just way too much to explain in one answer, so read my guide on XDA-Developers.
Here is the link:
http://forum.xda-developers.com/showpost.php?p=44513199
Also, I'm currently working on a library which will simplify the process of implementing you remote media controls.

I should be able to do this with PowerAMP using their [API][1], but have, but I really want a solution that works for the stock android player and others too.
There is no documented and supported API for the AOSP Music app or the Google Play Music app, AFAIK. They certainly are not in the Android SDK.
I am not aware of an Android ecosystem standard for media players exposing this information, let alone a roster of apps that support such a standard. You are welcome to work with the developers of such apps and encourage them to create and adopt a standard.
My thoughts are that I could maybe access this info from the info bar at the top as the now playing info is printed up there.
It is not possible to spy on other applications' Notifications, for obvious privacy and security reasons.

For a moment I got excited about the RemoteControlClient.MetadataEditor from 4.0, but then I figured out that it was for writing that information to a stream that can be sent to the physical remote, rather than allowing you to create a software remote. Damn!
Surely there's a way to access the Remote Control Client metadata on Android 4.0, because the lock screen is able to access it when media is playing.
I'm not a developer at all, but I've tried to do a bit of poking around in the AOKP sources and this is my limited understanding of how it works. At least in AOKP (and presumably AOSP as well, then), it appears that the lockscreen uses core/java/com/android/internal/widget/TransportControlView.java to draw the music control widget on the lockscreen, which in turn uses media/java/android/media/IRemoteControlDisplay.aidl for data retrieval. At the very least, it may be useful to poke around in TransportControlView.java to see if you can figure out how the lockscreen widget works.

Related

Check/observe what is currently being played by the Android system

I'm looking for a solution to observe what the app is currently playing. At minimum I would need to know what URI is being used to play Media and what is current playback position.
We are giving developers API with media content (MP3/HLS files) and to give them the best experience we are asking them to send various events to our API. Based on those events we can prepare better content for their users. We would like to ease the process of tracking events by implementing library that will be responsible for tracking those events. To do it we need to observe/query what their app is currently playing and what is a playback position. That's why I'm looking for a solution that will let me do this without caring too much what kind of player app is using (MediaPlayer, ExoPlayer or any other solution).
Is there any tool that will let me check those informations?

Is there a way to access TV audio?

I'm currently fiddling around with an idea, and therefor I'm looking for a potential way to access the Audio-Stream on a TV (regardless if SmartTV, Android, WebOS, ...), run some audio-filters on it, and then have it output.
I've briefly read through some of the API's, but it seems I'm only able to control the volume - which is not really what I want. Am I missing something, or is this not possible at the moment?
For webOS at the moment you can only:
setMuted
volumeDown
volumeUp
and the formats that can be supported it at the moment:
So you cannot change the audio from native side, the only way i can imagine for this to work is to use a js library or something similar that can be supported then make change and display it to users.
Reference:
http://developer.lge.com/webOSTV/api/webos-service-api/audio/

There is any Android API to record call conversation and/or automatically answer calls?

Scanned through the Android API (reference) documentation, but didn't find specific API that allows one to achieve the following:
Be notified of an incoming call
Automatically answer or reject the incoming call
While a call is in progress, be able to capture the audio
Play a pre-recorded message, after answering the call
The intention behind the questions, as most might have guessed, is to have an automated answering machine type of application. I have seen such applications on Nokia Symbian OS devices.
If such functionality requires rooting the device, I'd still be interested in knowing the API's available once rooted!
As an aside, is there are separate API reference documentation for API's available to rooted devices ?
For the latter parts of your question, No.
Imagine for a second there was, and you had an app installed that uses it. It could record your conversations and send them to a 3rd party. The app might not even disclose that it does this.
That sounds like it would be a huge security problem... Don't you agree?
It would appear I am mistaken about the call recording part - several apps available on google play (such as this, this, and this) does call recording, at least of the user making the call.
For #1, this is covered by marcin_j's answer
For #2, these SO answers show you can accept or reject a call programmatically.
For #3, I did a bit more detailed search on this, which reveals a related Stackoverflow question and answer, which provides info on recording audio (as per the above linked apps). Please keep in mind there are likely legal requirements around recording calls.
For #4 (playing a message to the caller), the only info I was able to find on this says it is not supported. It's hard to find much more info on this with so much clutter on search coming up with apps that are basically an audio version of caller id.
Most of these answers are on StackOverflow already; hopefully bringing it all together here helps you.
You can use android.intent.action.PHONE_STATE broadcast, and check TelephonyManager.CALL_STATE_RINGING state. Requires android.permission.READ_PHONE_STATE.
2/3. Dont think you can do this, at least not on non-rooted phones. Maybe someone else will give better answer.

Continuous Speechrecognition in Android

I googled around and found the regular speech-api from google. But I think this isn't what I need. I need continious voice recognition and the ability to launch other actions when a specific word is spoken. Is there anything in the android sdk that I can use?
If not: Is it possible to implement third-party libraries? (If yes: which - and what do I have to think about when implement a third-party-library?)
Edit: I thought about this again. I have to recognize just one 'word' (that probably won't be in googles-speech-databases). I have the chance to record it. That means, I'm able to continiously match the incoming audio-stream against my recording. That should work without a database. But I'm new to android-development. Do you have suggestions for APIs to use for recording and matching the recorded? Or is there any better way to continiously wait for a specifig 'word' to occur and then process any further actions?
btw: if that wasn't clear described: the app should continue to record and watch for the word to occure again when the reaction is done.
Is there anything in the android sdk that I can use?
No, sorry.

Is there something in the Android architecture or API that prevents people from creating MP3 players that read embedded lyrics?

When I play certain MP3 files (such as lessons from JapanesePod101.com) on my iPod Touch, lyrics or transcripts that are embedded in the MP3 files are displayed in the media player. The lyrics are, I believe, stored as ID3/ID4 tags in the MP3 metadata.
I find this to be an extremely useful feature, and I believe I'm not alone. Despite that, neither the stock Android media player nor any other media player I've downloaded from the Market seems to support this. I just have not been able to find any way to get feature on my Nexus One.
This feature is important enough to me that I'm considering learning Android development just so I can write a simple media player that displays embedded lyrics or notes. However, the fact that nobody else seems to have done this makes me wonder - is it even possible? Is there something in the Android architecture or APIs that make it difficult or impossible to read and display lyrics information from MP3 files? I'd hate to get deep into the learning process and find out what I'm aiming for can't easily be done. (I mean, if all else fails I assume I could write my own MP3-decoder, but that's more trouble than I'm willing to go through right now).
I've already asked this question on the Android Enthusiasts Stack Exchange Beta Site, but in retrospect I decided it was more of a programming question and decided it was better to ask here.
Yeah, definitely more of a programming question. Just from my brief experience of reading through the ID3 spec, I think it's probably just that decoding ID3 tags is a complete PITA. I'm sure it can be done, as there are MP3 tag editing apps available for Android (whether any support lyrics or not, I do not know).
ID3v2.3 seems to have support for both synchronized and unsynchronized lyrics through the SYLT and USLT frames of the header. I imagine it's just such an underused feature that it isn't worth the effort to most to do so. Purchased MP3s don't carry this information (I've always wondered why not?), so they would have to manually be added (or automatically via a lyric service API, but there's a lot more coding involved with that).
Here is the ID3v2.3 spec if you'd like to look into it further...(abandon hope all ye who enter here)
The problem may be that most people would use the built-in mp3 playback mechanisms, and this may neither support lyric display nor be very easy to keep synchronized with something else doing lyric display.
So it may be that something needs to be written which does it's own mp3 decoding.
Most likely this would want to be done in native code. On the other hand, on android, audio output (and unless you use opengl, video display) pretty much has to be done from java. So you are looking at a fair amount of work to decode data with a native library and then dispatch it for playback and display from java.
So to answer your question - is it possible? Definitely
Is it made easy by the android APIs? - not really
I just added a new feature request that would give Android support for reading USLT in the ID3 tag. This will enable the native and 3rd party music players to display lyrics. If you want this feature, please star the request below, and post your comments.
http://code.google.com/p/android/issues/detail?id=32547

Categories

Resources