//——————————————————
//recorder.h
//------------------------------------
#import <UIKit/UIKit.h>
#import <AudioToolbox/AudioQueue.h>
#import <AudioToolbox/AudioFile.h>
#define NUM_BUFFERS 3
#define kAudioConverterPropertyMaximumOutputPacketSize 'xops'
#define DOCUMENTS_FOLDER [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"]
typedef struct
{
AudioFileID audioFile;
AudioStreamBasicDescription dataFormat;
AudioQueueRef queue;
AudioQueueBufferRef buffers[NUM_BUFFERS];
UInt32 bufferByteSize;
SInt64 currentPacket;
BOOL recording;
} RecordState;
@interface Recorder : NSObject {
RecordState recordState;
}
- (BOOL) isRecording;
- (float) averagePower;
- (float) peakPower;
- (float) currentTime;
- (BOOL) startRecording: (NSString *) filePath;
- (void) stopRecording;
- (void) pause;
- (BOOL) resume;
@end
//——————————————————
//recorder.m
//------------------------------------
#import "Recorder.h"
#define SAMPLES_PER_SECOND 8000.0f
// Derive the Buffer Size. I punt with the max buffer size.
void DeriveBufferSize (AudioQueueRef audioQueue, AudioStreamBasicDescription ASBDescription, Float64 seconds, UInt32 *outBufferSize)
{
static const int maxBufferSize = 0x50000; // punting with 50k
int maxPacketSize = ASBDescription.mBytesPerPacket;
if (maxPacketSize == 0)
{
UInt32 maxVBRPacketSize = sizeof(maxPacketSize);
AudioQueueGetProperty(audioQueue, kAudioConverterPropertyMaximumOutputPacketSize, &maxPacketSize, &maxVBRPacketSize);
}
Float64 numBytesForTime = ASBDescription.mSampleRate * maxPacketSize * seconds;
*outBufferSize = (UInt32)((numBytesForTime < maxBufferSize) ? numBytesForTime : maxBufferSize);
}
// Handle new input
static void HandleInputBuffer (void *aqData, AudioQueueRef inAQ, AudioQueueBufferRef inBuffer, const AudioTimeStamp *inStartTime,
UInt32 inNumPackets, const AudioStreamPacketDescription *inPacketDesc)
{
RecordState *pAqData = (RecordState *) aqData;
if (inNumPackets == 0 && pAqData->dataFormat.mBytesPerPacket != 0)
inNumPackets = inBuffer->mAudioDataByteSize / pAqData->dataFormat.mBytesPerPacket;
if (AudioFileWritePackets(pAqData->audioFile, NO, inBuffer->mAudioDataByteSize, inPacketDesc, pAqData->currentPacket, &inNumPackets, inBuffer->mAudioData) == noErr)
{
pAqData->currentPacket += inNumPackets;
if (pAqData->recording == 0) return;
AudioQueueEnqueueBuffer (pAqData->queue, inBuffer, 0, NULL);
}
}
@implementation Recorder
// Initialize the recorder
- (id) init
{
if (self = [super init]) recordState.recording = NO;
return self;
}
// Set up the recording format as low quality mono AIFF
- (void)setupAudioFormat:(AudioStreamBasicDescription*)format
{
format->mSampleRate = SAMPLES_PER_SECOND;
format->mFormatID = kAudioFormatLinearPCM;
format->mFormatFlags = kLinearPCMFormatFlagIsBigEndian | kLinearPCMFormatFlagIsSignedInteger | kLinearPCMFormatFlagIsPacked;
format->mChannelsPerFrame = 1; // mono
format->mBitsPerChannel = 16;
format->mFramesPerPacket = 1;
format->mBytesPerPacket = 2;
format->mBytesPerFrame = 2;
format->mReserved = 0;
}
// Begin recording
- (BOOL) startRecording: (NSString *) filePath
{
// file url
[self setupAudioFormat:&recordState.dataFormat];
CFURLRef fileURL = CFURLCreateFromFileSystemRepresentation(NULL, (const UInt8 *) [filePath UTF8String], [filePath length], NO);
// recordState.currentPacket = 0;
// new input queue
OSStatus status;
status = AudioQueueNewInput(&recordState.dataFormat, HandleInputBuffer, &recordState, CFRunLoopGetCurrent(),kCFRunLoopCommonModes, 0, &recordState.queue);
if (status) {CFRelease(fileURL); printf("Could not establish new queue\n"); return NO;}
// create new audio file
status = AudioFileCreateWithURL(fileURL, kAudioFileAIFFType, &recordState.dataFormat, kAudioFileFlags_EraseFile, &recordState.audioFile);
CFRelease(fileURL); // thanks august joki
if (status) {printf("Could not create file to record audio\n"); return NO;}
// figure out the buffer size
DeriveBufferSize(recordState.queue, recordState.dataFormat, 0.5, &recordState.bufferByteSize);
// allocate those buffers and enqueue them
for(int i = 0; i < NUM_BUFFERS; i++)
{
status = AudioQueueAllocateBuffer(recordState.queue, recordState.bufferByteSize, &recordState.buffers[i]);
if (status) {printf("Error allocating buffer %d\n", i); return NO;}
status = AudioQueueEnqueueBuffer(recordState.queue, recordState.buffers[i], 0, NULL);
if (status) {printf("Error enqueuing buffer %d\n", i); return NO;}
}
// enable metering
UInt32 enableMetering = YES;
status = AudioQueueSetProperty(recordState.queue, kAudioQueueProperty_EnableLevelMetering, &enableMetering,sizeof(enableMetering));
if (status) {printf("Could not enable metering\n"); return NO;}
// start recording
status = AudioQueueStart(recordState.queue, NULL);
if (status) {printf("Could not start Audio Queue\n"); return NO;}
recordState.currentPacket = 0;
recordState.recording = YES;
return YES;
}
- (float) averagePower
{
AudioQueueLevelMeterState state[1];
UInt32 statesize = sizeof(state);
OSStatus status;
status = AudioQueueGetProperty(recordState.queue, kAudioQueueProperty_CurrentLevelMeter, &state, &statesize);
if (status) {printf("Error retrieving meter data\n"); return 0.0f;}
return state[0].mAveragePower;
}
- (float) peakPower
{
AudioQueueLevelMeterState state[1];
UInt32 statesize = sizeof(state);
OSStatus status;
status = AudioQueueGetProperty(recordState.queue, kAudioQueueProperty_CurrentLevelMeter, &state, &statesize);
if (status) {printf("Error retrieving meter data\n"); return 0.0f;}
return state[0].mPeakPower;
}
// There's generally about a one-second delay before the buffers fully empty
- (void) reallyStopRecording
{
AudioQueueFlush(recordState.queue);
AudioQueueStop(recordState.queue, NO);
recordState.recording = NO;
for(int i = 0; i < NUM_BUFFERS; i++)
AudioQueueFreeBuffer(recordState.queue, recordState.buffers[i]);
AudioQueueDispose(recordState.queue, YES);
AudioFileClose(recordState.audioFile);
}
// Stop the recording after waiting just a second
- (void) stopRecording
{
[self performSelector:@selector(reallyStopRecording) withObject:NULL afterDelay:1.0f];
}
- (void) reallyPauseRecording
{
if (!recordState.queue) {printf("Nothing to pause\n"); return;}
OSStatus status = AudioQueuePause(recordState.queue);
if (status) {printf("Error pausing audio queue\n"); return;}
}
- (void) pause
{
[self performSelector:@selector(reallyPauseRecording) withObject:NULL afterDelay:0.5f];
}
- (BOOL) resume
{
if (!recordState.queue){printf("Nothing to resume\n"); return NO;}
OSStatus status = AudioQueueStart(recordState.queue, NULL);
if (status) {printf("Error restarting audio queue\n"); return NO;}
return YES;
}
// Return the current time
- (float) currentTime
{
AudioTimeStamp outTimeStamp;
OSStatus status = AudioQueueGetCurrentTime (recordState.queue, NULL, &outTimeStamp, NULL);
if (status) {printf("Error: Could not retrieve current time\n"); return 0.0f;}
return outTimeStamp.mSampleTime / SAMPLES_PER_SECOND;
}
// Return whether the recording is active
- (BOOL) isRecording
{
return recordState.recording;
}
@end
//如何使用
//开始停止录制
- (IBAction) buttonPushed
{
// Establish recorder
if (!self.myRecorder) self.myRecorder = [[[Recorder alloc] init] autorelease];
if (!self.myRecorder)
{
NSLog(@"Error: Could not create recorder");
return;
}
pauseButton.enabled=YES;
if (!isRecording)
{
recorderFilePath=[FILEPATH retain];
BOOL success = [self.myRecorder startRecording:recorderFilePath];
if (!success)
{
printf("Error starting recording\n");
[self.myRecorder stopRecording];
self.myRecorder = nil;
isRecording = NO;
return;
}
}
else
{
[self.myRecorder stopRecording];
self.myRecorder = nil;
self.title = nil;
}
isRecording = !isRecording;
// Handle the GUI updates
if (isRecording)
{
// start monitoring the power level
timer = [NSTimer scheduledTimerWithTimeInterval:0.1f target:self selector:@selector(updateStatus) userInfo:nil repeats:YES];
// Update the button art
[button setImage:[UIImage imageNamed:@"lyJs2.png"] forState:UIControlStateNormal];
}
else
{
// Stop monitoring the power level
[timer invalidate];
timer = nil;
// Update the button art
// 这里建立一个委托方法，用于返回给调用数据给调用类
if([delegate respondsToSelector:@selector(recordViewController:didFinishRecordingWithInfo:)])
{
[delegate performSelector:@selector(recordViewController:didFinishRecordingWithInfo:) withObject:self withObject:recorderFilePath];
}
}
}
//暂停或者继续按钮事件
-(IBAction)pauseButtonPressed
{
if(isPaused)
{
[self.myRecorder resume];
isPaused=NO;
[self.pauseButton setImage:[UIImage imageNamed:@"lyZt.png"] forState:UIControlStateNormal];
}
else
{
[self.myRecorder pause];
isPaused=YES;
[self.pauseButton setImage:[UIImage imageNamed:@"lyKs.png"] forState:UIControlStateNormal];
}
}