第一帧一直黑屏的原因：在写的时候要判断是视频先，然后开始写入！！！
- (void)captureOutput:(AVCaptureOutput *)captureOutput didOutputSampleBuffer:(CMSampleBufferRef)sampleBuffer fromConnection:(AVCaptureConnection *)connection {
if (!_recoding) return;
@autoreleasepool {
_currentSampleTime = CMSampleBufferGetOutputPresentationTimeStamp(sampleBuffer);
if (captureOutput == _videoDataOut && _assetWriter.status != AVAssetWriterStatusWriting && _assetWriter.status != AVAssetWriterStatusFailed) {
[_assetWriter startWriting];
[_assetWriter startSessionAtSourceTime:_currentSampleTime];
}
if (captureOutput == _videoDataOut) {
if (_assetWriterPixelBufferInput.assetWriterInput.isReadyForMoreMediaData) {
CVPixelBufferRef pixelBuffer = CMSampleBufferGetImageBuffer(sampleBuffer);
[self getStillImage:sampleBuffer];
BOOL success = [_assetWriterPixelBufferInput appendPixelBuffer:pixelBuffer withPresentationTime:_currentSampleTime];
if (!success) {
NSLog(@"Pixel Buffer没有append成功");
}
}
}
if (captureOutput == _audioDataOut) {
if(_assetWriter.status != AVAssetWriterStatusUnknown){
[_assetWriterAudioInput appendSampleBuffer:sampleBuffer];
}
}
}
}
视频方向判断
#pragma mark - 重力感应相关
- (CMMotionManager *)motionManager {
if (!_motionManager) {
_motionManager = [[CMMotionManager alloc] init];
}
return _motionManager;
}
/**
* 开始监听屏幕方向
*/
- (void)startUpdateAccelerometer {
HCWS(ws);
if ([self.motionManager isAccelerometerAvailable] == YES) {
//回调会一直调用,建议获取到就调用下面的停止方法，需要再重新开始，当然如果需求是实时不间断的话可以等离开页面之后再stop
[self.motionManager setAccelerometerUpdateInterval:1.0];
[self.motionManager startAccelerometerUpdatesToQueue:[NSOperationQueue currentQueue] withHandler:^(CMAccelerometerData *accelerometerData, NSError *error) {
double x = accelerometerData.acceleration.x;
double y = accelerometerData.acceleration.y;
if (fabs(y) >= fabs(x)) {
if (y >= 0) {
DLog(@"----Down");
ws.shootingOrientation = UIDeviceOrientationPortraitUpsideDown;
}
else {
DLog(@"----Portrait");
ws.shootingOrientation = UIDeviceOrientationPortrait;
}
}
else {
if (x >= 0) {
DLog(@"----Right");
ws.shootingOrientation = UIDeviceOrientationLandscapeRight;
}
else {
DLog(@"----Left");
ws.shootingOrientation = UIDeviceOrientationLandscapeLeft;
}
}
}];
}
}
/**
* 停止监听屏幕方向
*/
- (void)stopUpdateAccelerometer {
if ([self.motionManager isAccelerometerActive] == YES) {
[self.motionManager stopAccelerometerUpdates];
_motionManager = nil;
}
}
- (void)canBtnActive {
[self stopUpdateAccelerometer];
}
- (void)backVideoAction {
[self startUpdateAccelerometer];
}
视频旋转
if (self.shootingOrientation == UIDeviceOrientationLandscapeRight)
{
_assetWriterVideoInput.transform = _isAVCaptureDevicePositionFront ? CGAffineTransformMakeRotation(0) : CGAffineTransformMakeRotation(M_PI);
}
else if (self.shootingOrientation == UIDeviceOrientationLandscapeLeft)
{
_assetWriterVideoInput.transform = _isAVCaptureDevicePositionFront ? CGAffineTransformMakeRotation(M_PI) : CGAffineTransformMakeRotation(0);
}
else if (self.shootingOrientation == UIDeviceOrientationPortraitUpsideDown)
{
_assetWriterVideoInput.transform = _isAVCaptureDevicePositionFront ? CGAffineTransformMakeRotation(M_PI / 2.0) : CGAffineTransformMakeRotation(M_PI + (M_PI / 2.0));
}
else
{
_assetWriterVideoInput.transform = _isAVCaptureDevicePositionFront ? CGAffineTransformMakeRotation(M_PI + (M_PI / 2.0)) : CGAffineTransformMakeRotation(M_PI / 2.0);
}
视频镜像
- (void)videoMirored {
AVCaptureSession* session = (AVCaptureSession *)_videoSession;
for (AVCaptureVideoDataOutput* output in session.outputs) {
for (AVCaptureConnection * av in output.connections) {
//判断是否是前置摄像头状态
if (_isAVCaptureDevicePositionFront) {
if (av.supportsVideoMirroring) {
//镜像设置
av.videoMirrored = YES;
}
}
}
}
}
缩略图旋转
+ (void)saveThumImageWithVideoURL:(NSURL *)videoUrl second:(int64_t)second orientation:(UIDeviceOrientation) shootingOrientation captureDevicePositionFront:(BOOL)isFront {
AVURLAsset *urlSet = [AVURLAsset assetWithURL:videoUrl];
AVAssetImageGenerator *imageGenerator = [AVAssetImageGenerator assetImageGeneratorWithAsset:urlSet];
CMTime time = CMTimeMake(second, 10);
NSError *error = nil;
CGImageRef cgimage = [imageGenerator copyCGImageAtTime:time actualTime:nil error:&error];
if (error) {
NSLog(@"缩略图获取失败!:%@",error);
return;
}
UIImage *image = [UIImage imageWithCGImage:cgimage];
UIImage *finalImage = nil;
if (shootingOrientation == UIDeviceOrientationLandscapeRight)
{
finalImage = [self rotateImage:image withOrientation:UIImageOrientationDown captureDevicePositionFront:isFront];
}
else if (shootingOrientation == UIDeviceOrientationLandscapeLeft)
{
finalImage = [self rotateImage:image withOrientation:UIImageOrientationUp captureDevicePositionFront:isFront];
}
else if (shootingOrientation == UIDeviceOrientationPortraitUpsideDown)
{
finalImage = [self rotateImage:image withOrientation:UIImageOrientationLeft captureDevicePositionFront:isFront];
}
else
{
finalImage = [self rotateImage:image withOrientation:UIImageOrientationRight captureDevicePositionFront:isFront];
}
NSData *imgData = UIImageJPEGRepresentation(finalImage, 1.0);
NSString *videoPath = [videoUrl.absoluteString stringByReplacingOccurrencesOfString:@"file://" withString: @""];
NSString *thumPath = [videoPath stringByReplacingOccurrencesOfString:@"mp4" withString: @"JPG"];
BOOL isok = [imgData writeToFile:[SourceManage getFilePathName:[thumPath md5Hex] fileType:forFileImage] atomically: YES];
NSLog(@"缩略图获取结果:%d",isok);
CGImageRelease(cgimage);
}
+ (UIImage *)rotateImage:(UIImage *)image withOrientation:(UIImageOrientation)orientation captureDevicePositionFront:(BOOL)isFront
{
long double rotate = 0.0;
CGRect rect;
float translateX = 0;
float translateY = 0;
float scaleX = 1.0;
float scaleY = 1.0;
switch (orientation)
{
case UIImageOrientationLeft:
rotate = M_PI_2;
rect = CGRectMake(0, 0, image.size.height, image.size.width);
translateX = 0;
translateY = -rect.size.width;
scaleY = rect.size.width/rect.size.height;
scaleX = rect.size.height/rect.size.width;
break;
case UIImageOrientationRight:
rotate = 3 * M_PI_2;
rect = CGRectMake(0, 0, image.size.height, image.size.width);
translateX = -rect.size.height;
translateY = 0;
scaleY = rect.size.width/rect.size.height;
scaleX = rect.size.height/rect.size.width;
break;
case UIImageOrientationDown:
if (isFront) {
rotate = 0.0;
rect = CGRectMake(0, 0, image.size.width, image.size.height);
translateX = 0;
translateY = 0;
} else {
rotate = M_PI;
rect = CGRectMake(0, 0, image.size.width, image.size.height);
translateX = -rect.size.width;
translateY = -rect.size.height;
}
break;
default:
if (isFront) {
rotate = M_PI;
rect = CGRectMake(0, 0, image.size.width, image.size.height);
translateX = -rect.size.width;
translateY = -rect.size.height;
} else {
rotate = 0.0;
rect = CGRectMake(0, 0, image.size.width, image.size.height);
translateX = 0;
translateY = 0;
}
break;
}
UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
//做CTM变换
CGContextTranslateCTM(context, 0.0, rect.size.height);
CGContextScaleCTM(context, 1.0, -1.0);
CGContextRotateCTM(context, rotate);
CGContextTranslateCTM(context, translateX, translateY);
CGContextScaleCTM(context, scaleX, scaleY);
//绘制图片
CGContextDrawImage(context, CGRectMake(0, 0, rect.size.width, rect.size.height), image.CGImage);
UIImage *newPic = UIGraphicsGetImageFromCurrentImageContext();
return newPic;
}
压缩视频长度
+(void)CompressVideoUrlPath:(NSURL *)pathUrl startCompress:(StartCompress)start finishCompress:(FinishCompress)finish errorCompress:(errorCompress)err
{
AVURLAsset *avAsset = [AVURLAsset URLAssetWithURL:pathUrl options:nil];
//获取视频总时长
float duration = CMTimeGetSeconds(avAsset.duration);
float startTime = 0;
float endTime = duration;
NSArray *compatiblePresets = [AVAssetExportSession exportPresetsCompatibleWithAsset:avAsset];
LYVideoCompress *comp = [[LYVideoCompress alloc] init];
if ([compatiblePresets containsObject:AVAssetExportPresetMediumQuality]) {
AVAssetExportSession *exportSession = [[AVAssetExportSession alloc] initWithAsset:avAsset presetName:AVAssetExportPresetMediumQuality];
NSDateFormatter *formater = [[NSDateFormatter alloc] init];//用时间给文件全名，以免重复，在测试的时候其实可以判断文件是否存在若存在，则删除，重新生成文件即可
[formater setDateFormat:@"yyyy-MM-dd-HH:mm:ss"];
comp.compressFilePath = [[self getFilePath] stringByAppendingFormat:@"%@.mp4", [formater stringFromDate:[NSDate date]]];
exportSession.outputURL = [NSURL fileURLWithPath:comp.compressFilePath];
exportSession.outputFileType = AVFileTypeMPEG4;
exportSession.shouldOptimizeForNetworkUse = YES;
CMTime start = CMTimeMakeWithSeconds(startTime, avAsset.duration.timescale);
CMTime duration = CMTimeMakeWithSeconds(endTime - startTime,avAsset.duration.timescale);
CMTimeRange range = CMTimeRangeMake(start, duration);
exportSession.timeRange = range;
[exportSession exportAsynchronouslyWithCompletionHandler:^(void)
{
if (exportSession.status == AVAssetExportSessionStatusCompleted) {
comp.fileSize = [self getFileSize:comp.compressFilePath];
comp.fileLength = [self getVideoLength:comp.compressFilePath];
comp.thumAbsolutePath = [self savaThumeImagePath:comp.compressFilePath];
UIImage *image = [UIImage imageWithContentsOfFile:comp.thumAbsolutePath];
comp.height = [NSString stringWithFormat:@"%f", image.size.height];
comp.width = [NSString stringWithFormat:@"%f", image.size.width];
finish(comp);
}else {
err(exportSession.error);
}
}];
}
}