首页 › Android开发 › 实例编程iPhone 录音和播放

李程站 发表于 2013-2-4 02:28:37

实例编程iPhone 录音和播放

实例编程iPhone 录音和播放是本文要介绍的内容，最近准备做一个关于录音和播放的项目！查了一些资料，很简单的做了一个，下面我就分享一下iPhone的录音和播放的使用心得。iPhone的录音和播放使用到了media层的内容，media层处于cocoa层之下，用到的很大一部分都是c语言的结构。
1、引入框架。
#import <AVFoundation/AVFoundation.h>
2、创建录音项。

[*]- (void) prepareToRecord
[*]
[*]{
[*]
[*]AVAudioSession *audioSession = ;
[*]
[*]NSError *err = nil;
[*]
[*];
[*]
[*]if(err){
[*]
[*]      NSLog(@"audioSession: %@ %d %@", , , [ description]);
[*]
[*]      return;
[*]
[*]}
[*]
[*];
[*]
[*]err = nil;
[*]
[*]if(err){
[*]
[*]      NSLog(@"audioSession: %@ %d %@", , , [ description]);
[*]
[*]      return;
[*]
[*]}
[*]
[*]recordSetting = [ init];
[*]
[*] forKey:AVFormatIDKey];
[*]
[*] forKey:AVSampleRateKey];   
[*]
[*] forKey:AVNumberOfChannelsKey];
[*]
[*] forKey:AVLinearPCMBitDepthKey];
[*]
[*] forKey:AVLinearPCMIsBigEndianKey];
[*]
[*] forKey:AVLinearPCMIsFloatKey];
[*]
[*]// Create a new dated file
[*]NSDate *now = ;
[*]NSString *caldate = ;
[*]recorderFilePath = [ retain];
[*]NSURL *url = ;
[*]err = nil;
[*]recorder = [[ AVAudioRecorder alloc] initWithURL:url settings:recordSetting error:&err];
[*]if(!recorder){
[*]      NSLog(@"recorder: %@ %d %@", , , [ description]);
[*]      UIAlertView *alert =
[*]      [ initWithTitle: @"Warning"
[*]message:
[*]delegate: nil
[*]cancelButtonTitle:@"OK"
[*]otherButtonTitles:nil];
[*]      ;
[*]      ;
[*]      return;
[*]}
[*]//prepare to record
[*];
[*];
[*]recorder.meteringEnabled = YES;
[*]BOOL audioHWAvailable = audioSession.inputIsAvailable;
[*]if (! audioHWAvailable) {
[*]      UIAlertView *cantRecordAlert =
[*]      [ initWithTitle: @"Warning"
[*]message: @"Audio input hardware not available"
[*]delegate: nil
[*]cancelButtonTitle:@"OK"
[*]otherButtonTitles:nil];
[*]      ;
[*]      ;   
[*]      return;
[*]}
[*]}
以上这个方法就是创建了录音项，其中包括录音的路径和一些音频属性，但只是准备录音还没有录，如果要录的话还要加入以下的方法：

[*](void)startrecorder
[*]{
[*];
[*]}
这样就在我们创建的路径下开始了录音。完成录音很简单：

[*](void) stopRecording{
[*];
[*]}
这里顺便提一下录音的代理方法：

[*]- (void)audioRecorderDidFinishRecording:(AVAudioRecorder *) aRecorder successfully:(BOOL)flag
[*]{
[*]NSLog(@"recorder successfully");
[*]UIAlertView *recorderSuccessful = [ initWithTitle:@"" message:@"录音成功"
[*]delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
[*];
[*];
[*]}
[*]
[*]- (void)audioRecorderEncodeErrorDidOccur:(AVAudioRecorder *)arecorder error:(NSError *)error
[*]{
[*]btnRecorder.enabled = NO;
[*]UIAlertView *recorderFailed = [ initWithTitle:@"" message:@"发生错误"
[*]delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
[*];
[*];
[*]}
以上两个代理方法分别指定了录音的成功或失败。
录音中有一个的录音对象有一个averagePowerForChannel和peakPowerForChannel的属性分别为声音的最高振幅和平均振幅，有了他们就可以做一个动态的振幅的录音效果。

[*]- (void) updateAudioDisplay {
[*]
[*]if (isStart == NO) {
[*]
[*]currentTimeLabel.text = @"--:--";
[*]
[*]} else {
[*]
[*]double currentTime = recorder.currentTime;
[*]
[*]currentTimeLabel.text = [NSString stringWithFormat: @"d:d",
[*]
[*](int) currentTime/60,
[*]
[*](int) currentTime%60];
[*]
[*]//START:code.RecordViewController.setlevelmeters
[*]
[*];
[*]
[*]
[*]
[*]peak: ];
[*]
[*]if (! rightLevelMeter.hidden) {
[*]
[*]
[*]
[*]peak: ];
[*]
[*]}
[*]
[*]//END:code.RecordViewController.setlevelmeters
[*]
[*]}
[*]
[*]}
[*]
[*]以上就是录音相关的内容。
[*]
[*]下面说一下播放的方法：
[*]
[*]void SystemSoundsDemoCompletionProc (
[*]SystemSoundIDsoundID,
[*]void         *clientData)
[*]{
[*]AudioServicesDisposeSystemSoundID (soundID);
[*]((AudioRecorderPlayerAppDelegate*)clientData).statusLabel.text = @"Stopped";
[*]}
[*]-(void)playAudio
[*]{
[*]//START:code.SystemSoundsDemo.SystemSoundsDemoViewController.createsystemsound
[*]// create a system sound id for the selected row
[*]SystemSoundID soundID;
[*]OSStatus err = kAudioServicesNoError;
[*]// special case: vibrate//震动
[*]//soundID = kSystemSoundID_Vibrate; //<label id="code.SystemSoundsDemo.SystemSoundsDemoViewController.createsystemsound.vibratesystemsound"/>
[*]
[*]// find corresponding CAF file
[*]
[*]//NSString *cafName = ; //<label id="code.SystemSoundsDemo.
[*]SystemSoundsDemoViewController.createsystemsound.rowtonumberstring"/>
[*]
[*]NSURL *url = ;
[*]//NSString *cafPath =   
[*]//[ pathForResource:cafName ofType:@"caf"]; //<label id="code.SystemSoundsDemo.
[*]SystemSoundsDemoViewController.createsystemsound.findcafinbundle"/>
[*]//NSURL *cafURL = ; //<label id="code.SystemSoundsDemo.SystemSoundsDemoViewController.
[*]createsystemsound.fileurlwithpath"/>
[*]err = AudioServicesCreateSystemSoundID((CFURLRef) url, &soundID); //<label id="code.SystemSoundsDemo.
[*]SystemSoundsDemoViewController.createsystemsound.createsystemsound"/>
[*]//END:code.SystemSoundsDemo.SystemSoundsDemoViewController.createsystemsound
[*]//START:code.SystemSoundsDemo.SystemSoundsDemoViewController.registercompletionprocandplaysound
[*]if (err == kAudioServicesNoError) {
[*]
[*]// set up callback for sound completion
[*]err = AudioServicesAddSystemSoundCompletion //<label id="code.SystemSoundsDemo.SystemSoundsDemoViewController.
[*]createsystemsound.addcompletionproc"/>
[*](soundID,// sound to monitor
[*]NULL,// run loop (NULL==main)
[*]NULL,// run loop mode (NULL==default)
[*]SystemSoundsDemoCompletionProc, // callback function //<label id="code.SystemSoundsDemo.
[*]SystemSoundsDemoViewController.createsystemsound.completionprocroutine"/>
[*]self // data to provide on callback
[*]); //<label id="code.SystemSoundsDemo.SystemSoundsDemoViewController.createsystemsound.addcompletionprocend"/>
[*]statusLabel.text = @"Playing"; //<label id="code.SystemSoundsDemo.SystemSoundsDemoViewController.createsystemsound.setlabel"/>
[*]AudioServicesPlaySystemSound (soundID); //<label id="code.SystemSoundsDemo.SystemSoundsDemoViewController.createsystemsound.playsound"/>
[*]}
[*]if (err != kAudioServicesNoError) { //<label id="code.SystemSoundsDemo.SystemSoundsDemoViewController.createsystemsound.errorblockstart"/>
[*]CFErrorRef error = CFErrorCreate(NULL, kCFErrorDomainOSStatus, err, NULL); //<label id="code.SystemSoundsDemo.
[*]SystemSoundsDemoViewController.createsystemsound.createcferror"/>
[*]NSString *errorDesc = (NSString*) CFErrorCopyDescription (error); //<label id="code.SystemSoundsDemo.
[*]SystemSoundsDemoViewController.createsystemsound.copycferrordescription"/>
[*]UIAlertView *cantPlayAlert =
[*][ initWithTitle:@"Cannot Play:"
[*]message: errorDesc
[*]delegate:nil
[*]cancelButtonTitle:@"OK"
[*]otherButtonTitles:nil];
[*];
[*];   
[*]; //<label id="code.SystemSoundsDemo.SystemSoundsDemoViewController.createsystemsound.releaseerrordescription"/>
[*]CFRelease (error); //<label id="code.SystemSoundsDemo.SystemSoundsDemoViewController.createsystemsound.releaseerror"/>
[*]} //<label id="code.SystemSoundsDemo.SystemSoundsDemoViewController.createsystemsound.errorblockend"/>
[*]//END:code.SystemSoundsDemo.SystemSoundsDemoViewController.registercompletionprocandplaysound
[*]}
通过以上的方法就应该能够实现播放，播放的时候也是可以加入振幅过程的，大家可以试试！这样一个iPhone录音机就做好了！哈哈
小结：实例编程iPhone 录音和播放的内容介绍完了，希望本文对你有所帮助。
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