Comments on: Exploring iPhone Audio Part 1

By: nebos

nebos — Wed, 03 Sep 2008 21:31:58 +0000

any way to control the audio input, or is the built-in mic the only option (is there an audio line input in the UDC?)

any way to control the actual gain of said input to compensate for very loud sounds in the external environment?

By: Gilbert Mackall

Gilbert Mackall — Sun, 17 Aug 2008 01:35:15 +0000

Can’t get the iPhone to accept this description

aqData.mDataFormat.mSampleRate = 8000.0;
aqData.mDataFormat.mFormatID = kAudioFormatLinearPCM;
aqData.mDataFormat.mFormatFlags = kAudioFormatFlagIsFloat | kAudioFormatFlagIsBigEndian ;
//aqData.mDataFormat.mFormatFlags = kAudioFormatFlagIsSignedInteger| kLinearPCMFormatFlagIsPacked;
aqData.mDataFormat.mFramesPerPacket = 1;
aqData.mDataFormat.mChannelsPerFrame = 1;
aqData.mDataFormat.mBitsPerChannel = 32;
aqData.mDataFormat.mBytesPerPacket = 4;
aqData.mDataFormat.mBytesPerFrame = 4;

By: peeInMyPantz

peeInMyPantz — Mon, 28 Jul 2008 18:23:26 +0000

what do I need modify to let this code play AMR file?

By: Mp3 Playback - iPhone Dev SDK Forums

Mp3 Playback - iPhone Dev SDK Forums — Thu, 24 Jul 2008 16:50:20 +0000

[...] Originally Posted by StrAbZ The fact is that I need to play mp3 since, the user of the application downloads the files before they are played, and mp3 are still one of the smallest audio files. Maybe I didn’t used the right word, by using "sound", since, that’s audio files from about 5 to 10 min that I need to play… You said that I only can play 5 sec files… but AudioQueueServices can play longer files… (the wav I play is about 40s). So I don’t understand what you meaned… thank u Oh… Sorry, I missed the part of (AudioQueueServices) lol… Yea, you should be able to use mp3 in it. I’ve always been told to stay away from mp3 on the iphone. So that’s why I convert everything but in your case you said you need it because of file size. I don’t see why you couldn’t use AAC? AAC isn’t that far off from mp3 in size. Anyways, have a look at this link. It should help you. iPhone Audio (7 Parts) [...]

By: Exploring iPhone Audio Part 2 | Trails in the Sand

Exploring iPhone Audio Part 2 | Trails in the Sand — Wed, 26 Mar 2008 19:35:28 +0000

[...] Last time we created the RecordState structure to keep track of the recording state. We also configured the recording parameter to record 8000 samples per second, 16 bit, mono audio. [...]