Can I somehow use a loaded audio tag to create an audio buffer?
I know that the web audio API has a decodeAudioData method that can be used to create an audio buffer, but it does not accept an audio tag.
How can I take an audio tag and use it to create an audio buffer that can be played by a source node?
Sadly, it doesn't look like the audio tag can be loaded into a buffer. The only way so far to create an AudioBuffer is through XMLHttpRequest or creating an empty buffer.
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In unity engine I want record audio from microphone with pause/resume ability; I want to have all of recorded audio in one AudioClip at final; and I don't know how many time it will pause and play (it's depend to user, not me) (also length of it) what can I do ?
Don't have ready made solution, but the way you should start is to use Microphone class and use its Start and End function to record audio. This returns an audio clip which can be save to a numbered file (e.g., audio_datetime_00001,audio_datetime_00002,...). Once user Play/Pause/Stop you can create a new audio file. Later you can merge them using NAudio (try Mark Heath's solution).
Happy coding!!!
I am working on media recording on IOS. I was able to record with both audio and video using UIImagePickerController. For my specification I want to record only audio. Is it possible with UIImagePickerController? or Do I need to think about other methods?
thanks.
UIImagePickerController cannot be used to record audio. Instead you should take a look at the SpeakHere sample code from Apple.
Also check Audio Queue - Recording to a compressed audio format on how to record as compressed audio format and conserve disk space.
What I'm doing :
I need to play audio and video files that are not supported by Apple on iPhone/iPad for example mkv/mka files which my contain several audio channels.
I'm using libffmpeg to find audio and video streams in media file.
Video is being decoded with avcodec_decode_video2 and audio with avcodec_decode_audio3
the return values are following for each function are following
avcodec_decode_video2 - returns AVFrame structure which encapsulates information about the video video frame from the pakcage, specifically is has data field which is a pointer to the picture/channel planes.
avcodec_decode_audio3 - returns samples of type int16_t * which I guess is the raw audio data
So basically I've done all this and successfully decoding the media content.
What I have to do :
I've to play the audio and video accordingly using Apples services. The playback I need to perform should support mixing of audio channels while playing video, i.e. let say mkv file contains two audio channel and a video channel. So I would like to know which service will be the appropriate choice for me ? My research showed that AudioQueue service might be useful audio playback, and probably AVFoundation for video.
Please help to find the right technology for my case i.e. video playeback + audio playback with possible audio channel mixing.
You are on the right path. If you are only playing audio (not recording at all) then I would use AudioQueues. It will do the mixing for you. If you are recording then you should use AudioUnits. Take a look at the MixerHost example project from Apple. For video I recommend using OpenGL. Assuming the image buffer is in YUV420 then you can render this with a simple two pass shader setup. I do believe there is an Apple example project showing how to do this. In any case you could render any pixel format using OpenGL and a shader to convert the pixel format to RGBA. Hope this help.
I am looking at Apple's 'aurioTouch' example for the iPhone and I would like to play an mp3 or wav instead of using the built in mic. I am very new to the audio portion of iPhone programming, but I think I need to modify the SetupRemoteIO(...) function and replace the AudioComponent named 'comp' with a custom AudioComponent that plays a file. Basically I want the app to function exactly the same as the original, but with an audio file as the input instead of the mic.
You just need to convert your audio file to pcm data and then feed that data to the RemoteIO interface during the playback callback.
To read your audio file in, you will want to use ExtAudioFileOpenURL and ExtAudioFileRead. Also make sure to set your audio format with ExtAudioFileSetProperty to convert to your target pcm format (which should be packed, signed integer PCM data).
Playback simply involves responding to the RemoteIO callback (which should be identical to aurioTouch's example) and feeding it the PCM data you loaded up.
The only other tricky part is that loading an entire mp3 file as PCM can take up a ton of memory. You might have to write a loading thread so that you can stay under your memory requirements by only loading your relevant chunk of the mp3.
Is it possible to play audio and video file at a same time? I want to play different audio file and video file at a same time and also want control for both, so is it possible?
Sorry, not that I know of. The movie view automatically stops all audio files and takes up the whole screen, so you are forced to listen to the audio for the video.
If the audio is part of the video file, yes.
If it's an MP3 file or some other external type how are you planning on playing it? The phone might allow this to happen depending on what you're up too.
You might be in luck soon though...
Another helpful link is here.