Question

我使用avmutablecomposition合并了四个肖像视频。但最终的视频方向改为横向。视频的尺寸为720 x 1280。

我检查了多次解决问题，但我的解决方案并不奏效。

这是我的代码：

    AVMutableComposition *composition = [AVMutableComposition composition];
    AVMutableCompositionTrack *compositionVideoTrack = [composition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid];
    AVMutableCompositionTrack *compositionAudioTrack = [composition addMutableTrackWithMediaType:AVMediaTypeAudio preferredTrackID:kCMPersistentTrackID_Invalid];
    AVMutableVideoComposition *videoComposition = [AVMutableVideoComposition videoComposition];
    videoComposition.frameDuration = CMTimeMake(1,30);
    videoComposition.renderScale = 1.0;

AVMutableVideoCompositionInstruction *instruction = [AVMutableVideoCompositionInstruction videoCompositionInstruction];

AVMutableVideoCompositionLayerInstruction *layerInstruction = [AVMutableVideoCompositionLayerInstruction videoCompositionLayerInstructionWithAssetTrack:compositionVideoTrack];



NSLog(@"%@",videoPathArray);

// Get only paths the user selected
NSMutableArray *array = [NSMutableArray array];
for(NSString* string in videoPathArray){
    if(![string isEqualToString:@""]){
        [array addObject:string];
    }
}

videoPathArray = array;
float time = 0;
CMTime startTime = kCMTimeZero;

for (int i = 0; i<videoPathArray.count; i++) {

    AVURLAsset *sourceAsset = [AVURLAsset URLAssetWithURL:[NSURL fileURLWithPath:[videoPathArray objectAtIndex:i]] options:[NSDictionary dictionaryWithObject:[NSNumber numberWithBool:YES] forKey:AVURLAssetPreferPreciseDurationAndTimingKey]];

    NSError *error = nil;

    if ([[sourceAsset tracksWithMediaType:AVMediaTypeVideo] count] != 0){

    BOOL ok = NO;
    AVAssetTrack *sourceVideoTrack = [[sourceAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0];
    AVAssetTrack *sourceAudioTrack = [[sourceAsset tracksWithMediaType:AVMediaTypeAudio] objectAtIndex:0];

    CGSize temp = CGSizeApplyAffineTransform(sourceVideoTrack.naturalSize, sourceVideoTrack.preferredTransform);
    CGSize size = CGSizeMake(fabsf(temp.width), fabsf(temp.height));
    CGAffineTransform transform = sourceVideoTrack.preferredTransform;

    videoComposition.renderSize = sourceVideoTrack.naturalSize;
    if (size.width > size.height) {

        [layerInstruction setTransform:transform atTime:CMTimeMakeWithSeconds(time, 30)];
    } else {

        float s = size.width/size.height;

        CGAffineTransform newOne = CGAffineTransformConcat(transform, CGAffineTransformMakeScale(s,s));

        float x = (size.height - size.width*s)/2;

        CGAffineTransform newer = CGAffineTransformConcat(newOne, CGAffineTransformMakeTranslation(x, 0));

        [layerInstruction setTransform:newer atTime:CMTimeMakeWithSeconds(time, 30)];

    }

    if(i == 0 )
    {
        [compositionVideoTrack setPreferredTransform:sourceVideoTrack.preferredTransform];
    }

    ok = [compositionVideoTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, [sourceAsset duration]) ofTrack:sourceVideoTrack atTime:startTime error:&error];


    ok = [compositionAudioTrack insertTimeRange:CMTimeRangeMake(kCMTimeZero, [sourceAsset duration]) ofTrack:sourceAudioTrack atTime:startTime error:nil];

    if (!ok) {
        {
            [radialView4 setHidden:YES];
            NSLog(@"Export failed: %@", [[self.exportSession error] localizedDescription]);
            UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Error" message:@"Something Went Wrong :("  delegate:nil cancelButtonTitle:@"Ok" otherButtonTitles: nil, nil];
            [alert show];
            [radialView4 setHidden:YES];
            break;
        }

    }

    NSLog(@"\n source asset duration is %f \n source vid track timerange is %f %f \n composition duration is %f \n composition vid track time range is %f %f",CMTimeGetSeconds([sourceAsset duration]), CMTimeGetSeconds(sourceVideoTrack.timeRange.start),CMTimeGetSeconds(sourceVideoTrack.timeRange.duration),CMTimeGetSeconds([composition duration]), CMTimeGetSeconds(compositionVideoTrack.timeRange.start),CMTimeGetSeconds(compositionVideoTrack.timeRange.duration));

    startTime = CMTimeAdd(startTime, [sourceAsset duration]);
    }
}

instruction.layerInstructions = [NSArray arrayWithObject:layerInstruction];
instruction.timeRange = compositionVideoTrack.timeRange;

videoComposition.instructions = [NSArray arrayWithObject:instruction];

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
NSString *myPathDocs =  [documentsDirectory stringByAppendingPathComponent:
                         [NSString stringWithFormat:@"RampMergedVideo.mov"]];
unlink([myPathDocs UTF8String]);
NSURL *url = [NSURL fileURLWithPath:myPathDocs];

AVAssetExportSession *exporter = [[AVAssetExportSession alloc] initWithAsset:composition
                                                                  presetName:AVAssetExportPreset1280x720];
exporter.outputURL=url;
exporter.outputFileType = AVFileTypeQuickTimeMovie;
exporter.shouldOptimizeForNetworkUse = YES;
[exporter exportAsynchronouslyWithCompletionHandler:^{
    dispatch_async(dispatch_get_main_queue(), ^{

        switch ([exporter status]) {
            case AVAssetExportSessionStatusFailed:
                NSLog(@"Export failed: %@", [exporter error]);
                break;
            case AVAssetExportSessionStatusCancelled:
                NSLog(@"Export canceled");
                break;
            case AVAssetExportSessionStatusCompleted:{

                break;
            }
            default:
                break;
        }
        if (exporter.status != AVAssetExportSessionStatusCompleted){
            NSLog(@"Retry export");

        }

    });
}];

videoPathArray：（＆＃34; /var/mobile/Containers/Data/Application/0C143367-043C-410F-B5D0-50D7DB097CBE/Documents/trimmedFirst.mov" ;, ＆＃34; /var/mobile/Containers/Data/Application/0C143367-043C-410F-B5D0-50D7DB097CBE/Documents/trimFilterApplied.mov" ;, ＆＃34; /var/mobile/Containers/Data/Application/0C143367-043C-410F-B5D0-50D7DB097CBE/Documents/trimmedSecond.mov" ;, ＆＃34; /var/mobile/Containers/Data/Application/0C143367-043C-410F-B5D0-50D7DB097CBE/Documents/ramp_logo_portrait.mov" ）

有人可以就我的问题提出建议吗？

视频方向在AVMutableComposition中更改

0 个答案: