Mam kilka plików wideo, które chcę połączyć w jeden plik wideo, używam NSMutableData, aby osiągnąć zadanie

NSMutableData *concatenatedData = [[NSMutableData alloc] init];
for (int i=0; i <[videoArray count]; i ++) {
  [concatenatedData appendData: [videoArray objectAtIndex:i]];
}
[concatenatedData writeToFile:[[NSString alloc] initWithFormat:@"%@%@", NSTemporaryDirectory(), @"outputConct.mov"] atomically:YES];
UISaveVideoAtPathToSavedPhotosAlbum([[NSString alloc] initWithFormat:@"%@%@", NSTemporaryDirectory(),@"outputConct.mov"], nil, nil, nil);

po zapisaniu filmu w rolce aparatu próbuję go odtworzyć, ale tylko pierwsze wideo NSData jest w nim zawarte. Nie wiem dlaczego.

edytować

Próbowałem AVMutableComposition, nawet wtedy mam te same problemy

AVMutableComposition* mixComposition = [[AVMutableComposition alloc] init];
        AVURLAsset* firstAsset;
        AVMutableCompositionTrack *firstTrack;
        CMTime time = kCMTimeZero;
        for (int i=0; i<[videoArray count]; i++) {
            firstAsset = [[AVURLAsset alloc]initWithURL:[NSURL fileURLWithPath:[[NSString alloc] initWithFormat:@"%@%d%@", NSTemporaryDirectory(),i, @"output.mov"]] options:nil];
            firstTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
            [firstTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, firstAsset.duration) ofTrack:[[firstAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] atTime:time error:nil];
            time = firstAsset.duration;
        }

        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];
        // 5 - Create exporter
        AVAssetExportSession *exporter = [[AVAssetExportSession alloc] initWithAsset:mixComposition
                                                                          presetName:AVAssetExportPresetHighestQuality];
        exporter.outputURL=url;
        exporter.outputFileType = AVFileTypeQuickTimeMovie;
        exporter.shouldOptimizeForNetworkUse = YES;
        [exporter exportAsynchronouslyWithCompletionHandler:^{
            dispatch_async(dispatch_get_main_queue(), ^{
                if (exporter.status == AVAssetExportSessionStatusCompleted) {
                    //NSURL *outputURL = exporter.outputURL;
                    UISaveVideoAtPathToSavedPhotosAlbum(myPathDocs, nil, nil, nil);
                }
            });
        }];

edytować

Próbowałem również tego, ale to daje mi błąd, mówi[__NSArrayM insertObject:atIndex:]: object cannot be nil'

AVMutableComposition *mixComposition = [AVMutableComposition composition];
AVMutableCompositionTrack *compositionTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
NSError * error = nil;
NSMutableArray * timeRanges = [NSMutableArray arrayWithCapacity:[videoArray count]];
NSMutableArray * tracks = [NSMutableArray arrayWithCapacity:[videoArray count]];
for (int i=0; i<[videoArray count]; i++) {
    AVURLAsset *assetClip = [[AVURLAsset alloc]initWithURL:[NSURL fileURLWithPath:[[NSString alloc] initWithFormat:@"%@%d%@", NSTemporaryDirectory(),i, @"output.mov"]] options:nil];
    AVAssetTrack *clipVideoTrackB = [[assetClip tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];

    [timeRanges addObject:[NSValue valueWithCMTimeRange:CMTimeRangeMake(kCMTimeZero, assetClip.duration)]];
    [tracks addObject:clipVideoTrackB];
}
[compositionTrack insertTimeRanges:timeRanges ofTracks:tracks atTime:kCMTimeZero error:&error];

To jest linia, w której program się zawiesza.

[compositionTrack insertTimeRanges:timeRanges ofTracks:tracks atTime:kCMTimeZero error:&error];

Nie jestem pewien, dlaczego zarówno timeRanges, jak i utwory mają w sobie wartości