i have a good experince with playing audio in general on iphone but i would like to have a way to play .RM files on iphone app .. i've tried the normal approach put it didn't give me any sound at all ..
so any help??
You'll need to convert these RealMedia files into a more modern format before you can play them.
You could learn the file format and write your own decoder and obtain the pcm data, or whatever format you want the samples in, and then feed that to either AudioQueues or AudioUnits.
Related
In this link it says it does:
http://developer.apple.com/library/ios/#documentation/AudioVideo/Conceptual/MultimediaPG/UsingAudio/UsingAudio.html
However I have searched for an example that works on the web and can only see people complaining they can't get it to work. I have a working AudioQueue example for PCM but the very moment I switch this to AAC initialization fails. SpeakHere example also only uses PCM.
Has anyone ever managed to make this work or has a link to a code snippet that works?
Basically iPhone only record PCM. To get an AAC encoded file the original PCM stream should be stored into a AudioFile and then this AudioFile should be converted to AAC.
There's no way to record and convert on the fly on iPhone unless you include a third-party library that will do this for you.
I need to convert image sequences(ie,png) to video file in iPhone. How i can convert the images to video.
Regards,
Just ignore bad advice like "use ffmpeg". That would work on the desktop, but the license issue makes including ffmpeg source code in your iPhone app legally questionable. Apple provides a class named AVAssetWriter that you would use in your app to encode a series of images as h.264 stored in a .m4v quicktime container file. While the apple provided logic does work, it is not so easy to actually use and you will need to read quite a lot of documentation to get the code working. If you want to skip implementing it yourself (and likely save yourself 3 or 4 days of work), please consider using my AVAnimator library for iOS as the h.264 encoding logic is already implemented in the class AVAssetWriterConvertFromMaxvid. Once encoded as h.264, the video can be played with the standard player and it is small enough to upload to a remote server.
You are likely going to need something like FFMPEG
Is it possible to play .mid files directly via some API, or one have to convert the midi file to e.g. AAC first?
(2 years later…) You can use MusicPlayer and MusicSequence APIs. Available in iOS 5.
There is no Apple API for this. You could write your own, which i think would depend on what you are hoping it is going sound like.
There is lots of available source code for reading midi files and there are a few open source synths for the iphone - or you could use openAl for triggering samples. It probably isn't going to sound like Garageband tho.
If you want it to sound as good as possible you will have to convert it first.
As of right now I am using ffmpeg to convert from .mp3 --> to .aiff but I would like a native way to do this in xcode but i do not understand how to use AudioConverter.h in AudioToolbox soo if someone could please help me I would be really appreciative.
Thank You
Enea
ExtAudioFile can do a fantastic job of this. One reason to take some compressed formats like MP3 and convert to PCM is that there is much less of a latency when playing the sound. An MP3 sound effect, for example, can take close to a second to start playing back, when the same sound in PCM could start almost immediately. I know since I am converting my sounds to PCM at launch time and eliminating the delays I was plagued with.
Go download iPhoneExtAudioFileConvertTest and you will find everything you need to do your own conversions
I think the real question is why would you want to? The iphone and AudioQueue has full mp3 support for playback and mixing. I know of no way to do this on the fly in the iPhone. It is a fairly processor intensive task and I doubt you could do it efficiently on the iPhone anyway.
You can use ExtAudioFile to open and convert the file to CAF with PCM data.
Can iphone mix two sound files or build custom equalizer?
I have studied for weeks about this problem,
and it seems unable to use iphone-sdk to mix two or more sound files or to build custom equalizer.
Is anyone have the experience to do this?
Yes you can. AVAudioPlayer can play multiple sounds and you can control the volume for each. Or you can use Audio Units and have more control over the audio data.
aurioTouch is a good sample app for what you are thinking of.
For simple playback of sound files you can use the AVAudioPlayer class introduced in the 2.2 SDK. It provides playback and volume controls for playing any audio file. As far as I am aware, there are no restrictions on the number of sound files you can play on the iPhone. The only restriction on playing sound files is that you may only play one AAC or MP3 compressed file at a time, the rest of the files must be either uncompressed or in the IMA4 format.
If your needs are more low-level (If you need to do DSP) you might want to look at AudioQueue Services or AudioUnits - two Mac OS X audio processing APIs that are also available on the iPhone.