IOS-recording function

Initialize AVAudioRecorder and set the recording parameters and storage address:

[Cpp]
// Recording settings
NSMutableDictionary * recordSetting = [[NSMutableDictionary alloc] init] autorelease];
// Set the recording format AVFormatIDKey = kAudioFormatLinearPCM
[RecordSetting setValue: [NSNumber numberWithInt: kAudioFormatMPEG4AAC] forKey: AVFormatIDKey];
// Set the recording sampling rate (Hz), for example, AVSampleRateKey = 8000/44100/96000 (which affects the audio quality)
[RecordSetting setValue: [NSNumber numberWithFloat: 44100] forKey: AVSampleRateKey];
// Number of recording channels: 1 or 2
[RecordSetting setValue: [NSNumber numberWithInt: 1] forKey: AVNumberOfChannelsKey];
// Linear sampling digits: 8, 16, 24, and 32
[RecordSetting setValue: [NSNumber numberWithInt: 16] forKey: AVLinearPCMBitDepthKey];
// Recording quality
[RecordSetting setValue: [NSNumber numberWithInt: AVAudioQualityHigh] forKey: AVEncoderAudioQualityKey];

NSString * strUrl = [NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
NSURL * url = [NSURL fileURLWithPath: [NSString stringWithFormat: @ "% @/lll. aac", strUrl];
UrlPlay = url;

NSError * error;
// Initialization
Recorder = [[AVAudioRecorder alloc] initWithURL: url settings: recordSetting error: & error];
// Enable Volume Detection
Recorder. meteringEnabled = YES;
Recorder. delegate = self;

// Recording settings
NSMutableDictionary * recordSetting = [[NSMutableDictionary alloc] init] autorelease];
// Set the recording format AVFormatIDKey = kAudioFormatLinearPCM
[RecordSetting setValue: [NSNumber numberWithInt: kAudioFormatMPEG4AAC] forKey: AVFormatIDKey];
// Set the recording sampling rate (Hz), for example, AVSampleRateKey = 8000/44100/96000 (which affects the audio quality)
[RecordSetting setValue: [NSNumber numberWithFloat: 44100] forKey: AVSampleRateKey];
// Number of recording channels: 1 or 2
[RecordSetting setValue: [NSNumber numberWithInt: 1] forKey: AVNumberOfChannelsKey];
// Linear sampling digits: 8, 16, 24, and 32
[RecordSetting setValue: [NSNumber numberWithInt: 16] forKey: AVLinearPCMBitDepthKey];
// Recording quality
[RecordSetting setValue: [NSNumber numberWithInt: AVAudioQualityHigh] forKey: AVEncoderAudioQualityKey];

NSString * strUrl = [NSSearchPathForDirectoriesInDomains (NSDocumentDirectory, NSUserDomainMask, YES) lastObject];
NSURL * url = [NSURL fileURLWithPath: [NSString stringWithFormat: @ "% @/lll. aac", strUrl];
UrlPlay = url;

NSError * error;
// Initialization
Recorder = [[AVAudioRecorder alloc] initWithURL: url settings: recordSetting error: & error];
// Enable Volume Detection
Recorder. meteringEnabled = YES;
Recorder. delegate = self;

 

Identify the volume size to display different images to show fluctuations in the volume chart

[Cpp]
[Recorder updateMeters]; // refresh the volume data
// Obtain the average volume [recorder averagePowerForChannel: 0];
// Maximum volume [recorder peakPowerForChannel: 0];

Double lowPassResults = pow (10, (0.05 * [recorder peakPowerForChannel: 0]);
NSLog (@ "% lf", lowPassResults );
// Up to 50 0
// Small image-large
If (0 <lowPassResults <= 0.06 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_01.png"];
} Else if (0.06 <lowPassResults <= 0.13 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_02.png"];
} Else if (0.13 <lowPassResults <= 0.20 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_03.png"];
} Else if (0.20 <lowPassResults <= 0.27 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_04.png"];
} Else if (0.27 <lowPassResults <= 0.34 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_05.png"];
} Else if (0.34 <lowPassResults <= 0.41 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_06.png"];
} Else if (0.41 <lowPassResults <= 0.48 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_07.png"];
} Else if (0.48 <lowPassResults <= 0.55 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_08.png"];
} Else if (0.55 <lowPassResults <= 0.62 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_09.png"];
} Else if (0.62 <lowPassResults <= 0.69 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_10.png"];
} Else if (0.69 <lowPassResults <= 0.76 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_11.png"];
} Else if (0.76 <lowPassResults <= 0.83 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_12.png"];
} Else if (0.83 <lowPassResults <= 0.9 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_13.png"];
} Else {
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_14.png"];
}

[Recorder updateMeters]; // refresh the volume data
// Obtain the average volume [recorder averagePowerForChannel: 0];
// Maximum volume [recorder peakPowerForChannel: 0];

Double lowPassResults = pow (10, (0.05 * [recorder peakPowerForChannel: 0]);
NSLog (@ "% lf", lowPassResults );
// Up to 50 0
// Small image-large
If (0 <lowPassResults <= 0.06 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_01.png"];
} Else if (0.06 <lowPassResults <= 0.13 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_02.png"];
} Else if (0.13 <lowPassResults <= 0.20 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_03.png"];
} Else if (0.20 <lowPassResults <= 0.27 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_04.png"];
} Else if (0.27 <lowPassResults <= 0.34 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_05.png"];
} Else if (0.34 <lowPassResults <= 0.41 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_06.png"];
} Else if (0.41 <lowPassResults <= 0.48 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_07.png"];
} Else if (0.48 <lowPassResults <= 0.55 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_08.png"];
} Else if (0.55 <lowPassResults <= 0.62 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_09.png"];
} Else if (0.62 <lowPassResults <= 0.69 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_10.png"];
} Else if (0.69 <lowPassResults <= 0.76 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_11.png"];
} Else if (0.76 <lowPassResults <= 0.83 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_12.png"];
} Else if (0.83 <lowPassResults <= 0.9 ){
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_13.png"];
} Else {
[Self. imageView setImage: [UIImage imageNamed: @ "record_animate_14.png"];
}