#import "VTM_AViPodReaderViewController.h"
#import <AudioToolbox/AudioToolbox.h> // for the core audio constants
#define EXPORT_NAME @"exported.caf"
@implementation VTM_AViPodReaderViewController
@synthesize songLabel;
@synthesize artistLabel;
@synthesize sizeLabel;
@synthesize coverArtView;
@synthesize conversionProgress;
#pragma mark init/dealloc
- (void)dealloc {
[super dealloc];
}
#pragma mark vc lifecycle
-(void) viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
}
#pragma mark event handlers
-(IBAction) convertTapped: (id) sender {
// set up an AVAssetReader to read from the iPod Library
NSURL *assetURL = [song valueForProperty:MPMediaItemPropertyAssetURL];
AVURLAsset *songAsset = [AVURLAsset URLAssetWithURL:assetURL options:nil];
NSError *assetError = nil;
AVAssetReader *assetReader = [[AVAssetReader assetReaderWithAsset:songAsset
error:&assetError]
retain];
if (assetError) {
NSLog (@"error: %@", assetError);
return;
}
AVAssetReaderOutput *assetReaderOutput = [[AVAssetReaderAudioMixOutput
assetReaderAudioMixOutputWithAudioTracks:songAsset.tracks
audioSettings: nil]
retain];
if (! [assetReader canAddOutput: assetReaderOutput]) {
NSLog (@"can't add reader output... die!");
return;
}
[assetReader addOutput: assetReaderOutput];
NSArray *dirs = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectoryPath = [dirs objectAtIndex:0];
NSString *exportPath = [[documentsDirectoryPath stringByAppendingPathComponent:EXPORT_NAME] retain];
if ([[NSFileManager defaultManager] fileExistsAtPath:exportPath]) {
[[NSFileManager defaultManager] removeItemAtPath:exportPath error:nil];
}
NSURL *exportURL = [NSURL fileURLWithPath:exportPath];
AVAssetWriter *assetWriter = [[AVAssetWriter assetWriterWithURL:exportURL
fileType:AVFileTypeCoreAudioFormat
error:&assetError]
retain];
if (assetError) {
NSLog (@"error: %@", assetError);
return;
}
AudioChannelLayout channelLayout;
memset(&channelLayout, 0, sizeof(AudioChannelLayout));
channelLayout.mChannelLayoutTag = kAudioChannelLayoutTag_Stereo;
NSDictionary *outputSettings = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithInt:kAudioFormatLinearPCM], AVFormatIDKey,
[NSNumber numberWithFloat:44100.0], AVSampleRateKey,
[NSNumber numberWithInt:2], AVNumberOfChannelsKey,
[NSData dataWithBytes:&channelLayout length:sizeof(AudioChannelLayout)], AVChannelLayoutKey,
[NSNumber numberWithInt:16], AVLinearPCMBitDepthKey,
[NSNumber numberWithBool:NO], AVLinearPCMIsNonInterleaved,
[NSNumber numberWithBool:NO],AVLinearPCMIsFloatKey,
[NSNumber numberWithBool:NO], AVLinearPCMIsBigEndianKey,
nil];
AVAssetWriterInput *assetWriterInput = [[AVAssetWriterInput assetWriterInputWithMediaType:AVMediaTypeAudio
outputSettings:outputSettings]
retain];
if ([assetWriter canAddInput:assetWriterInput]) {
[assetWriter addInput:assetWriterInput];
} else {
NSLog (@"can't add asset writer input... die!");
return;
}
assetWriterInput.expectsMediaDataInRealTime = NO;
[assetWriter startWriting];
[assetReader startReading];
AVAssetTrack *soundTrack = [songAsset.tracks objectAtIndex:0];
CMTime startTime = CMTimeMake (0, soundTrack.naturalTimeScale);
[assetWriter startSessionAtSourceTime: startTime];
__block UInt64 convertedByteCount = 0;
dispatch_queue_t mediaInputQueue = dispatch_queue_create("mediaInputQueue", NULL);
[assetWriterInput requestMediaDataWhenReadyOnQueue:mediaInputQueue
usingBlock: ^
{
// NSLog (@"top of block");
while (assetWriterInput.readyForMoreMediaData) {
CMSampleBufferRef nextBuffer = [assetReaderOutput copyNextSampleBuffer];
if (nextBuffer) {
// append buffer
[assetWriterInput appendSampleBuffer: nextBuffer];
// NSLog (@"appended a buffer (%d bytes)",
// CMSampleBufferGetTotalSampleSize (nextBuffer));
convertedByteCount += CMSampleBufferGetTotalSampleSize (nextBuffer);
// oops, no
// sizeLabel.text = [NSString stringWithFormat: @"%ld bytes converted", convertedByteCount];
NSNumber *convertedByteCountNumber = [NSNumber numberWithLong:convertedByteCount];
[self performSelectorOnMainThread:@selector(updateSizeLabel:)
withObject:convertedByteCountNumber
waitUntilDone:NO];
} else {
// done!
[assetWriterInput markAsFinished];
[assetWriter finishWriting];
[assetReader cancelReading];
NSDictionary *outputFileAttributes = [[NSFileManager defaultManager]
attributesOfItemAtPath:exportPath
error:nil];
NSLog (@"done. file size is %ld",
[outputFileAttributes fileSize]);
NSNumber *doneFileSize = [NSNumber numberWithLong:[outputFileAttributes fileSize]];
[self performSelectorOnMainThread:@selector(updateCompletedSizeLabel:)
withObject:doneFileSize
waitUntilDone:NO];
// release a lot of stuff
[assetReader release];
[assetReaderOutput release];
[assetWriter release];
[assetWriterInput release];
[exportPath release];
break;
}
}
}];
NSLog (@"bottom of convertTapped:");
}
-(void) updateSizeLabel: (NSNumber*) convertedByteCountNumber {
UInt64 convertedByteCount = [convertedByteCountNumber longValue];
sizeLabel.text = [NSString stringWithFormat: @"%ld bytes converted", convertedByteCount];
}
-(void) updateCompletedSizeLabel: (NSNumber*) convertedByteCountNumber {
UInt64 convertedByteCount = [convertedByteCountNumber longValue];
sizeLabel.text = [NSString stringWithFormat: @"done. file size is %ld", convertedByteCount];
}
@end
我在转换时遇到内存泄漏的主要问题。从我的调试和分析中,它显示:
[assetReader release];
[assetReaderOutput release];
[assetWriter release];
[assetWriterInput release];
[exportPath release];
保留1不释放。有人可以帮助解决这个问题吗?尝试转换第二首歌后,我的应用程序一直崩溃。
日志报告
/Users/cocellmac08/Documents/iphonedev/trying/Classes/SecondViewController.m:835:3 Potential leak of an object allocated on line 827 and stored into 'assetReader'
/Users/cocellmac08/Documents/iphonedev/trying/Classes/SecondViewController.m:849:3 Potential leak of an object allocated on line 841 and stored into 'assetReaderOutput'
/Users/cocellmac08/Documents/iphonedev/trying/Classes/SecondViewController.m:877:3 Potential leak of an object allocated on line 861 and stored into 'exportPath'
/Users/cocellmac08/Documents/iphonedev/trying/Classes/SecondViewController.m:877:3 Potential leak of an object allocated on line 870 and stored into 'assetWriter'
/Users/cocellmac08/Documents/iphonedev/trying/Classes/SecondViewController.m:903:3 Potential leak of an object allocated on line 895 and stored into 'assetWriterInput'
答案 0 :(得分:5)
我在if / else语句后面的while循环中用以下几行修复了内存泄漏,以确保nextBuffer真正被释放。
CMSampleBufferInvalidate(nextBuffer);
CFRelease(nextBuffer);
nextBuffer = nil; // NULL?
我没有在CMSampleBufferInvalidate的文档中看到任何细节,但我发现它在其他地方被引用,它确实似乎有所帮助。我也称CFRelease,最后将其设置为零。将其设置为NULL可能是更合适的方法,因为可能优先将其视为C级结构,而NULL是C方式而nil是Objective-C。我已经通过泄漏运行此代码,我没有看到我之前看到的主要泄漏。我仍然看到128字节的泄漏。我无法将其追溯到任何代码行。这是对以前泄漏版本的巨大改进。
答案 1 :(得分:0)
听起来可能像两个不同的问题(如果我理解这个问题); build&amp; analyze正在识别泄漏。崩溃是另一个问题。发布回溯。
一些问题;永远不要直接测试错误,看看是否发生了错误。你应该是:
if (!assetReader) {
... report assetError and return ...
}
似乎有许多代码路径会泄漏内存;例如,如果canAddOutput:
失败,则您不会在返回前发布assetReader
。
exportPath
不需要保留;如果块需要它,它将保留它。
答案 2 :(得分:0)
你结识了我的一天! tnx,我添加了这个: CMSampleBufferInvalidate(nextBuffer); CFRelease(nextBuffer); nextBuffer = nil; // 空值? 就在这之后:休息; }
而不是之前评论中所述,它看起来像是在工作! tnx再次。