IOS Audio Recording

New empty Applicaton, add Homeviewcontroller file. Just look at the code, it's too boring and the theory will be mentioned in the code. HomeViewController.h code: #import <UIKit/UIKit.h> #import <AVFoundation/AVFoundation.h> @interface Homeviewcontroller:uiviewcontroller <avaudiorecorderdelegate, avaudioplayerdelegate>{} @property (Nonatomic, Retain) Avaudiorecorder *audiorecorder;   @property (nonatomic, retain) Avaudioplayer *audioplayer; -(NSString *) Audiorecordingpath; -(Nsdictionary *) audiorecordingsettings; @end &NBSP;HOMEVIEWCONTROLLER.M code:   #import "HomeViewController.h"   @interface Homeviewcontroller ()   @end   @implementation Homeviewcontroller   @synthesize Audioplayer; @synthesize Audiorecorder;  //Setting the location of recorded audio files-(NSString *) audiorecordingpath{      nsstring *result = nil;     Nsarray *folders = Nssearchpathfordirectoriesindomains (NSDocumentDirectory, Nsuserdomainmask, YES);     NSString *documentsfolde = [folders objectatindex:0];     result = [Documentsfolde stringbyappendingpathcomponent:@ "recording.m4a"];     return (result);  //Before initializing the Avaudiorecord instance, basic recording settings are required-(nsdictionary *) audiorecordingsettings{      Nsdictionary *result = nil;          Nsmutabledictionary *settings = [[[Nsmutabledictionary alloc] init] autorelease];// Required parameter settings for recording          [Settings Setvalue:[nsnumber Numberwithinteger: Kaudioformatapplelossless]&nbsP                 Forkey:avformatidkey];          [Settings Setvalue:[nsnumber numberwithfloat:44100.0f] Forkey:avsampleratekey];          [Settings Setvalue:[nsnumber numberwithinteger:1] Forkey:avnumberofchannelskey];          [Settings Setvalue:[nsnumber numberwithinteger:avaudioqualitylow]                  Forkey:avencoderaudioqualitykey];          result = [Nsdictionary dictionarywithdictionary:settings];          return (result);  //Stop audio Recording-(void) Stoprecordingonaudiorecorder: (Avaudiorecorder *) recorder{      [Recorder stop ];  //Audiorecorderdidfinishrecording:successfully: Method-(void) When Avaudiorecorder object recording is terminated Audiorecorderdidfinishrecording: (Avaudiorecorder *) Recorder successfully: (BOOL) flag{     //If flag is true , representing the normal end of the recording, using AVAUdioplayer it out, otherwise logging failed cause     if (flag = YES) {        NSLOG (@) recording completed. ");         nserror *playbackerror = nil;         nserror *readingerror = nil;         NSData *filedata = [NSData datawithcontentsoffile:[self Audiorecordingpath] Options: nsdatareadingmapped error:&readingerror];                  Avaudioplayer *newplayer = [[Avaudioplayer alloc] Initwithda ta:filedata                                                                  &N bsp;error:&playbackerror];                  Self.audioplayer = Newplayer;         [Newplayer release];                  if (self.audioplayer!= nil) {            self.audioPlayer.delegate = self;           & nbsp if ([self.audioplayer preparetoplay] = YES &&                  [self Audioplayer Play] = = YES) {                NSLOG (@) to begin playback of recorded audio. ");            } else {                NSLOG (@) cannot play recorded Audio. ");                    }else {            NSLog (@) audio playback failed. ");        }             } else {        NSLOG (@ "The recording process terminated unexpectedly. ");    }     Self.audiorecorder = nil; }  -(void) viewdidload {    [super Viewdidload];          Nserror *error = nil;     NSString *pathofrecordingfile = [Self audioreCordingpath];          Nsurl *audiorecordingurl = [Nsurl fileurlwithpath:pathofrecordingfile];          Avaudiorecorder *newrecorder = [[Avaudiorecorder alloc]        &NBSP ;                             Initwithurl:audiorecordi ngurl                                &NBSP ;     Settings:[self Audiorecordingsettings]                                     error:&error];     Self.audiorecorder = Newrecorder;     [Newrecorder release];          if (Self.audiorecorder!= nil) {        Self.audioRecorder.delegate = self;                  if ([Self.audiorecorder preparetorEcord] = YES &&             [self.audiorecorder record] = yes] {    &NB Sp      //If Audiorecorder is successfully instantiated, start recording the sound. And the Performselector method is set to execute the Stoprecordingonaudiorecorder method after recording the sound 10s to stop recording             NSLog (@ "recording sound begins.) ");                          [self performselector: @selector ( Stoprecordingonaudiorecorder:                        withobje Ct:self.audioRecorder                        afterdelay:10.0f] ;                     } else {          &N Bsp NSLog (@) recording failed. ");             Self.audiorecorder =nil;        }} else {    NSLog (@) Auiorecorder instance creation failed. "); } }  -(void) Viewdidunload{      if (Self.audiorecorder!= nil) {        if ([Self.audiorecorder Isrecor Ding] = YES) {            [Self.audiorecorder stop];        }         Self.audiorecorder = nil;    }          if (Self.audioplayer!= nil) {        if ([Self.aud Ioplayer isplaying] = YES) {            [self.audioplayer stop];       &NBS P }         Self.audioplayer = nil;    }  -(void) dealloc{      [Audioplayer release];     [Audiorecorder release ];     [Super Dealloc]; }   @end   PS: Required parameter settings for recording audio Avformatidkey The format for recording audio. KAUDIOFORMATLINEARPCM:LPCM format kaudioformatac3:ac-3 format KAUDIOFORMATMPEG4AAC:AAC format KAUDIOFORMATMPEG4CELP:CELP format KAUDIOFORMATMPEG4HVXC:HVXC format KAUDIOFORMATMPEG4LAYER1:MP1 format KAUDIOFORMATMPEG4LAYER2:MP2 format Kaudioformatmpeg4layer3:mp3 format Kaudioformattimecode:time format Kaudioformatmidistream:midi format Kaudioformatapplelossless:alac format Video used when recording audio Avsampleratekey avnumberofchannelskey number of channels when recording audio Quality of Avencoderaudioqualitykey recorded audio Avaudioqualitymin Avaudioqualitylow Avaudioqualitymedium Avaudioqualityhigh Avaudioqualitymax