iOS实现录音转码MP3及转码BASE64上传示例
iOS 录音转码MP3及转码BASE64上传
一,开始录音
NSLog(@"开始录音"); [self startRecord]; - (void)startRecord { //删除上次生成的文件,保留最新文件 NSFileManager *fileManager = [NSFileManager defaultManager]; if ([NSTemporaryDirectory() stringByAppendingString:@"myselfRecord.mp3"]) { [fileManager removeItemAtPath:[NSTemporaryDirectory() stringByAppendingString:@"myselfRecord.mp3"] error:nil]; } if ([NSTemporaryDirectory() stringByAppendingString:@"selfRecord.wav"]) { [fileManager removeItemAtPath:[NSTemporaryDirectory() stringByAppendingString:@"selfRecord.wav"] error:nil]; } //开始录音 //录音设置 NSMutableDictionary *recordSetting = [[NSMutableDictionary alloc] init]; //设置录音格式 AVFormatIDKey==kAudioFormatLinearPCM [recordSetting setValue:[NSNumber numberWithInt:kAudioFormatLinearPCM] forKey:AVFormatIDKey]; //设置录音采样率(Hz) 如:AVSampleRateKey==8000/44100/96000(影响音频的质量), 采样率必须要设为11025才能使转化成mp3格式后不会失真 [recordSetting setValue:[NSNumber numberWithFloat:11025.0] forKey:AVSampleRateKey]; //录音通道数 1 或 2 ,要转换成mp3格式必须为双通道 [recordSetting setValue:[NSNumber numberWithInt:2] forKey:AVNumberOfChannelsKey]; //线性采样位数 8、16、24、32 [recordSetting setValue:[NSNumber numberWithInt:16] forKey:AVLinearPCMBitDepthKey]; //录音的质量 [recordSetting setValue:[NSNumber numberWithInt:AVAudioQualityHigh] forKey:AVEncoderAudioQualityKey]; //存储录音文件 recordUrl = [NSURL URLWithString:[NSTemporaryDirectory() stringByAppendingString:@"selfRecord.wav"]]; //初始化 audioRecorder = [[AVAudioRecorder alloc] initWithURL:recordUrl settings:recordSetting error:nil]; //开启音量检测 audioRecorder.meteringEnabled = YES; audioSession = [AVAudioSession sharedInstance];//得到AVAudioSession单例对象 if (![audioRecorder isRecording]) { [audioSession setCategory:AVAudioSessionCategoryPlayAndRecord error:nil];//设置类别,表示该应用同时支持播放和录音 [audioSession setActive:YES error:nil];//启动音频会话管理,此时会阻断后台音乐的播放. [audioRecorder prepareToRecord]; [audioRecorder peakPowerForChannel:0.0]; [audioRecorder record]; } }
二,停止录音
[self endRecord]; - (void)endRecord { [audioRecorder stop]; //录音停止 [audioSession setActive:NO error:nil]; //一定要在录音停止以后再关闭音频会话管理(否则会报错),此时会延续后台音乐播放 }
三,转码成MP3
- (void)transformCAFToMP3 { mp3FilePath = [NSURL URLWithString:[NSTemporaryDirectory() stringByAppendingString:@"myselfRecord.mp3"]]; @try { int read, write; FILE *pcm = fopen([[recordUrl absoluteString] cStringUsingEncoding:1], "rb"); //source 被转换的音频文件位置 fseek(pcm, 4*1024, SEEK_CUR); //skip file header FILE *mp3 = fopen([[mp3FilePath absoluteString] cStringUsingEncoding:1], "wb"); //output 输出生成的Mp3文件位置 const int PCM_SIZE = 8192; const int MP3_SIZE = 8192; short int pcm_buffer[PCM_SIZE*2]; unsigned char mp3_buffer[MP3_SIZE]; lame_t lame = lame_init(); lame_set_in_samplerate(lame, 11025.0); lame_set_VBR(lame, vbr_default); lame_init_params(lame); do { read = (int)fread(pcm_buffer, 2*sizeof(short int), PCM_SIZE, pcm); if (read == 0) write = lame_encode_flush(lame, mp3_buffer, MP3_SIZE); else write = lame_encode_buffer_interleaved(lame, pcm_buffer, read, mp3_buffer, MP3_SIZE); fwrite(mp3_buffer, write, 1, mp3); } while (read != 0); lame_close(lame); fclose(mp3); fclose(pcm); } @catch (NSException *exception) { NSLog(@"%@",[exception description]); } @finally { NSLog(@"MP3生成成功"); base64Str = [self mp3ToBASE64]; } }
四,上传需要转码BASE64
- (NSString *)mp3ToBASE64{ NSData *mp3Data = [NSData dataWithContentsOfFile:[NSTemporaryDirectory() stringByAppendingString:@"myselfRecord.mp3"]]; NSString *_encodedImageStr = [mp3Data base64Encoding]; NSLog(@"===Encoded image:\n%@", _encodedImageStr); return _encodedImageStr; }
备注:其中可以直接生成的.caf .wav 有压缩的MP3需要转格式,不能直接录音生成
以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持我们。
赞 (0)