iOS - 将两个视频合并为一个带音频的视频文件

Posted 2023-02-25

【中文标题】iOS - 将两个视频合并为一个带音频的视频文件

【英文标题】：iOS - Merge two video into single video file with audio

【发布时间】：2016-05-13 12:31:48

【问题描述】：

我想将 2 个视频文件与单个文件与音频合并。我可以合并 2 个视频文件，但合并后输出视频文件没有任何音频声音。甚至两个旧视频文件都有正确的音频。我已经按照这个教程进行操作：https://www.raywenderlich.com/13418/how-to-play-record-edit-videos-in-ios 任何建议都会很棒。谢谢大家。 我的代码：

- (IBAction)MergeAndSave:(id)sender
if(firstAsset !=nil && secondAsset!=nil)
    [ActivityView startAnimating];
    //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];

    AVMutableCompositionTrack *secondTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
    [secondTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, secondAsset.duration) ofTrack:[[secondAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] atTime:firstAsset.duration error:nil];

    //AUDIO TRACK
    if(audioAsset!=nil)
        AVMutableCompositionTrack *AudioTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
        [AudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, CMTimeAdd(firstAsset.duration, secondAsset.duration)) ofTrack:[[audioAsset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0] atTime:kCMTimeZero error:nil];
     

    AVMutableVideoCompositionInstruction * MainInstruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];
    MainInstruction.timeRange = CMTimeRangeMake(kCMTimeZero, CMTimeAdd(firstAsset.duration, secondAsset.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];

    AVMutableVideoCompositionLayerInstruction *SecondlayerInstruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:secondTrack];
    AVAssetTrack *SecondAssetTrack = [[secondAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
    UIImageOrientation SecondAssetOrientation_  = UIImageOrientationUp;
    BOOL  isSecondAssetPortrait_  = NO;
    CGAffineTransform secondTransform = SecondAssetTrack.preferredTransform;
    if(secondTransform.a == 0 && secondTransform.b == 1.0 && secondTransform.c == -1.0 && secondTransform.d == 0)  SecondAssetOrientation_= UIImageOrientationRight; isSecondAssetPortrait_ = YES;
    if(secondTransform.a == 0 && secondTransform.b == -1.0 && secondTransform.c == 1.0 && secondTransform.d == 0)  SecondAssetOrientation_ =  UIImageOrientationLeft; isSecondAssetPortrait_ = YES;
    if(secondTransform.a == 1.0 && secondTransform.b == 0 && secondTransform.c == 0 && secondTransform.d == 1.0)   SecondAssetOrientation_ =  UIImageOrientationUp;
    if(secondTransform.a == -1.0 && secondTransform.b == 0 && secondTransform.c == 0 && secondTransform.d == -1.0) SecondAssetOrientation_ = UIImageOrientationDown;
    CGFloat SecondAssetScaleToFitRatio = 320.0/SecondAssetTrack.naturalSize.width;
    if(isSecondAssetPortrait_)
        SecondAssetScaleToFitRatio = 320.0/SecondAssetTrack.naturalSize.height;
        CGAffineTransform SecondAssetScaleFactor = CGAffineTransformMakeScale(SecondAssetScaleToFitRatio,SecondAssetScaleToFitRatio);
        [SecondlayerInstruction setTransform:CGAffineTransformConcat(SecondAssetTrack.preferredTransform, SecondAssetScaleFactor) atTime:firstAsset.duration];
    else
        ;
        CGAffineTransform SecondAssetScaleFactor = CGAffineTransformMakeScale(SecondAssetScaleToFitRatio,SecondAssetScaleToFitRatio);
        [SecondlayerInstruction setTransform:CGAffineTransformConcat(CGAffineTransformConcat(SecondAssetTrack.preferredTransform, SecondAssetScaleFactor),CGAffineTransformMakeTranslation(0, 160)) atTime:firstAsset.duration];
    


    MainInstruction.layerInstructions = [NSArray arrayWithObjects:FirstlayerInstruction,SecondlayerInstruction,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];
         );
     ];

【问题讨论】：

显示本教程可能会对您有所帮助。 raywenderlich.com/13418/how-to-play-record-edit-videos-in-ios

【参考方案1】：

我创建了一个将多个视频合并为一个带音频的视频的存储库。

斯威夫特

https://github.com/Datt1994/DPVideoMerger-Swift

目标 C

https://github.com/Datt1994/DPVideoMerger

使用以下代码：

 AVMutableCompositionTrack *AudioTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
[AudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, firstAsset.duration) ofTrack:[[firstAsset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0] atTime:kCMTimeZero error:nil];
 AVMutableCompositionTrack *AudioTrack2 = [mixComposition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
[AudioTrack2 insertTimeRange:CMTimeRangeMake(kCMTimeZero, secondAsset.duration) ofTrack:[[secondAsset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0] atTime:firstAsset.duration error:nil];

代替您的以下代码：

if(audioAsset!=nil)
   AVMutableCompositionTrack *AudioTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
   [AudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, CMTimeAdd(firstAsset.duration, secondAsset.duration)) ofTrack:[[audioAsset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0] atTime:kCMTimeZero error:nil];

【讨论】：

你的 repo 没有很好的记录。如果有人不想使用你的仓库，你能解释一下如何解决这个问题吗？

您的 repo 也不处理视频剪辑的不同方向。

@Datt1994 不错的演示，但是当四个视频合并成网格形式时，音频不来了。怎么解决？

@Datt1994 我在合并后将两个视频播放到网格中。但我也需要音频。你能建议我如何在视频中添加音频组合吗？