我正在使用一个应用程序,用户从照片中选择视频并将其上传到服务器。由于我的服务器是.Net服务器,因此视频会轮换。我知道问题的原因可能与图像的情况相同(你可以参考我之前的回答https://stackoverflow.com/a/10601175/1030951),所以我用Google搜索并获得了修复视频方向的代码,我得到了来自RayWenderlich.com的代码,并按以下方式修改。现在我的输出视频工作正常,但视频是静音。它播放但不播放音频。如果我遗失了什么,请帮助我。
我传递-(void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
方法
- (void)fix:(NSDictionary*)pobjInfoDirectory withFileName:(NSString*)pstrOutputFileName
{
firstAsset = [AVAsset assetWithURL:[pobjInfoDirectory objectForKey:UIImagePickerControllerMediaURL]];
if(firstAsset !=nil)
{
//Create AVMutableComposition Object.This object will hold our multiple AVMutableCompositionTrack.
AVMutableComposition* mixComposition = [[AVMutableComposition alloc] init];
//VIDEO TRACK
AVMutableCompositionTrack *firstTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
[firstTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, firstAsset.duration) ofTrack:[[firstAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] atTime:kCMTimeZero error:nil];
AVMutableVideoCompositionInstruction * MainInstruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];
MainInstruction.timeRange = CMTimeRangeMake(kCMTimeZero, firstAsset.duration);
//FIXING ORIENTATION//
AVMutableVideoCompositionLayerInstruction *FirstlayerInstruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:firstTrack];
AVAssetTrack *FirstAssetTrack = [[firstAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
UIImageOrientation FirstAssetOrientation_ = UIImageOrientationUp;
BOOL isFirstAssetPortrait_ = NO;
CGAffineTransform firstTransform = FirstAssetTrack.preferredTransform;
if(firstTransform.a == 0 && firstTransform.b == 1.0 && firstTransform.c == -1.0 && firstTransform.d == 0)
{
FirstAssetOrientation_= UIImageOrientationRight; isFirstAssetPortrait_ = YES;
}
if(firstTransform.a == 0 && firstTransform.b == -1.0 && firstTransform.c == 1.0 && firstTransform.d == 0)
{
FirstAssetOrientation_ = UIImageOrientationLeft; isFirstAssetPortrait_ = YES;
}
if(firstTransform.a == 1.0 && firstTransform.b == 0 && firstTransform.c == 0 && firstTransform.d == 1.0)
{
FirstAssetOrientation_ = UIImageOrientationUp;
}
if(firstTransform.a == -1.0 && firstTransform.b == 0 && firstTransform.c == 0 && firstTransform.d == -1.0)
{
FirstAssetOrientation_ = UIImageOrientationDown;
}
CGFloat FirstAssetScaleToFitRatio = 320.0/FirstAssetTrack.naturalSize.width;
if(isFirstAssetPortrait_)
{
FirstAssetScaleToFitRatio = 320.0/FirstAssetTrack.naturalSize.height;
CGAffineTransform FirstAssetScaleFactor = CGAffineTransformMakeScale(FirstAssetScaleToFitRatio,FirstAssetScaleToFitRatio);
[FirstlayerInstruction setTransform:CGAffineTransformConcat(FirstAssetTrack.preferredTransform, FirstAssetScaleFactor) atTime:kCMTimeZero];
}
else
{
CGAffineTransform FirstAssetScaleFactor = CGAffineTransformMakeScale(FirstAssetScaleToFitRatio,FirstAssetScaleToFitRatio);
[FirstlayerInstruction setTransform:CGAffineTransformConcat(CGAffineTransformConcat(FirstAssetTrack.preferredTransform, FirstAssetScaleFactor),CGAffineTransformMakeTranslation(0, 160)) atTime:kCMTimeZero];
}
[FirstlayerInstruction setOpacity:0.0 atTime:firstAsset.duration];
MainInstruction.layerInstructions = [NSArray arrayWithObjects:FirstlayerInstruction,nil];;
AVMutableVideoComposition *MainCompositionInst = [AVMutableVideoComposition videoComposition];
MainCompositionInst.instructions = [NSArray arrayWithObject:MainInstruction];
MainCompositionInst.frameDuration = CMTimeMake(1, 30);
MainCompositionInst.renderSize = CGSizeMake(320.0, 480.0);
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *myPathDocs = [documentsDirectory stringByAppendingPathComponent:[NSString stringWithFormat:@"mergeVideo-%d.mov",arc4random() % 1000]];
NSURL *url = [NSURL fileURLWithPath:myPathDocs];
AVAssetExportSession *exporter = [[AVAssetExportSession alloc] initWithAsset:mixComposition presetName:AVAssetExportPresetHighestQuality];
exporter.outputURL=url;
exporter.outputFileType = AVFileTypeQuickTimeMovie;
exporter.videoComposition = MainCompositionInst;
exporter.shouldOptimizeForNetworkUse = YES;
[exporter exportAsynchronouslyWithCompletionHandler:^
{
dispatch_async(dispatch_get_main_queue(), ^{
[self exportDidFinish:exporter];
});
}];
}
}
- (void)exportDidFinish:(AVAssetExportSession*)session
{
if(session.status == AVAssetExportSessionStatusCompleted)
{
NSURL *outputURL = session.outputURL;
ALAssetsLibrary *library = [[ALAssetsLibrary alloc] init];
if ([library videoAtPathIsCompatibleWithSavedPhotosAlbum:outputURL])
{
if ([self.delegate respondsToSelector:@selector(videoExported)])
[self.delegate videoExported];
}
}
firstAsset = nil;
}
答案 0 :(得分:8)
在//VIDEO TRACK
部分
//AUDIO TRACK
AVMutableCompositionTrack *firstAudioTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
[firstAudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, firstAsset.duration) ofTrack:[[firstAsset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0] atTime:kCMTimeZero error:nil];
答案 1 :(得分:2)
AVURLAsset* videoAsset = [[AVURLAsset alloc]initWithURL:@"your video url here..." options:nil];
在AVMutableCompositionTrack
之后添加。
将此setPreferredTransform:
设置为您要以相同方向导出的源视频。
// Grab the source track from AVURLAsset for example.
AVAssetTrack *assetVideoTrack = [videoAsset tracksWithMediaType:AVMediaTypeVideo].lastObject;
// Grab the composition video track from AVMutableComposition you already made.
AVMutableCompositionTrack *compositionVideoTrack = [mixComposition tracksWithMediaType:AVMediaTypeVideo].lastObject;
// Apply the original transform.
if (assetVideoTrack && compositionVideoTrack) {
[compositionVideoTrack setPreferredTransform:assetVideoTrack.preferredTransform];
}